3196 lines
80 KiB
C
3196 lines
80 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Simple NUMA memory policy for the Linux kernel.
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*
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* Copyright 2003,2004 Andi Kleen, SuSE Labs.
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* (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc.
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*
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* NUMA policy allows the user to give hints in which node(s) memory should
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* be allocated.
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*
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* Support four policies per VMA and per process:
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*
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* The VMA policy has priority over the process policy for a page fault.
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*
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* interleave Allocate memory interleaved over a set of nodes,
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* with normal fallback if it fails.
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* For VMA based allocations this interleaves based on the
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* offset into the backing object or offset into the mapping
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* for anonymous memory. For process policy an process counter
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* is used.
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*
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* bind Only allocate memory on a specific set of nodes,
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* no fallback.
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* FIXME: memory is allocated starting with the first node
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* to the last. It would be better if bind would truly restrict
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* the allocation to memory nodes instead
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*
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* preferred Try a specific node first before normal fallback.
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* As a special case NUMA_NO_NODE here means do the allocation
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* on the local CPU. This is normally identical to default,
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* but useful to set in a VMA when you have a non default
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* process policy.
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*
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* preferred many Try a set of nodes first before normal fallback. This is
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* similar to preferred without the special case.
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*
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* default Allocate on the local node first, or when on a VMA
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* use the process policy. This is what Linux always did
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* in a NUMA aware kernel and still does by, ahem, default.
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*
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* The process policy is applied for most non interrupt memory allocations
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* in that process' context. Interrupts ignore the policies and always
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* try to allocate on the local CPU. The VMA policy is only applied for memory
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* allocations for a VMA in the VM.
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*
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* Currently there are a few corner cases in swapping where the policy
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* is not applied, but the majority should be handled. When process policy
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* is used it is not remembered over swap outs/swap ins.
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*
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* Only the highest zone in the zone hierarchy gets policied. Allocations
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* requesting a lower zone just use default policy. This implies that
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* on systems with highmem kernel lowmem allocation don't get policied.
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* Same with GFP_DMA allocations.
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*
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* For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between
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* all users and remembered even when nobody has memory mapped.
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*/
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/* Notebook:
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fix mmap readahead to honour policy and enable policy for any page cache
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object
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statistics for bigpages
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global policy for page cache? currently it uses process policy. Requires
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first item above.
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handle mremap for shared memory (currently ignored for the policy)
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grows down?
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make bind policy root only? It can trigger oom much faster and the
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kernel is not always grateful with that.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/mempolicy.h>
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#include <linux/pagewalk.h>
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#include <linux/highmem.h>
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#include <linux/hugetlb.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/sched/mm.h>
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#include <linux/sched/numa_balancing.h>
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#include <linux/sched/task.h>
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#include <linux/nodemask.h>
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#include <linux/cpuset.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/export.h>
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#include <linux/nsproxy.h>
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#include <linux/interrupt.h>
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#include <linux/init.h>
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#include <linux/compat.h>
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#include <linux/ptrace.h>
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#include <linux/swap.h>
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#include <linux/seq_file.h>
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#include <linux/proc_fs.h>
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#include <linux/migrate.h>
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#include <linux/ksm.h>
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#include <linux/rmap.h>
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#include <linux/security.h>
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#include <linux/syscalls.h>
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#include <linux/ctype.h>
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#include <linux/mm_inline.h>
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#include <linux/mmu_notifier.h>
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#include <linux/printk.h>
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#include <linux/swapops.h>
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#include <asm/tlbflush.h>
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#include <asm/tlb.h>
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#include <linux/uaccess.h>
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#include "internal.h"
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/* Internal flags */
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#define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */
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#define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */
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static struct kmem_cache *policy_cache;
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static struct kmem_cache *sn_cache;
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/* Highest zone. An specific allocation for a zone below that is not
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policied. */
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enum zone_type policy_zone = 0;
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/*
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* run-time system-wide default policy => local allocation
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*/
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static struct mempolicy default_policy = {
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.refcnt = ATOMIC_INIT(1), /* never free it */
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.mode = MPOL_LOCAL,
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};
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static struct mempolicy preferred_node_policy[MAX_NUMNODES];
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/**
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* numa_nearest_node - Find nearest node by state
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* @node: Node id to start the search
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* @state: State to filter the search
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*
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* Lookup the closest node by distance if @nid is not in state.
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*
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* Return: this @node if it is in state, otherwise the closest node by distance
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*/
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int numa_nearest_node(int node, unsigned int state)
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{
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int min_dist = INT_MAX, dist, n, min_node;
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if (state >= NR_NODE_STATES)
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return -EINVAL;
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if (node == NUMA_NO_NODE || node_state(node, state))
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return node;
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min_node = node;
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for_each_node_state(n, state) {
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dist = node_distance(node, n);
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if (dist < min_dist) {
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min_dist = dist;
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min_node = n;
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}
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}
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return min_node;
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}
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EXPORT_SYMBOL_GPL(numa_nearest_node);
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struct mempolicy *get_task_policy(struct task_struct *p)
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{
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struct mempolicy *pol = p->mempolicy;
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int node;
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if (pol)
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return pol;
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node = numa_node_id();
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if (node != NUMA_NO_NODE) {
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pol = &preferred_node_policy[node];
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/* preferred_node_policy is not initialised early in boot */
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if (pol->mode)
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return pol;
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}
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return &default_policy;
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}
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static const struct mempolicy_operations {
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int (*create)(struct mempolicy *pol, const nodemask_t *nodes);
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void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes);
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} mpol_ops[MPOL_MAX];
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static inline int mpol_store_user_nodemask(const struct mempolicy *pol)
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{
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return pol->flags & MPOL_MODE_FLAGS;
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}
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static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig,
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const nodemask_t *rel)
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{
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nodemask_t tmp;
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nodes_fold(tmp, *orig, nodes_weight(*rel));
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nodes_onto(*ret, tmp, *rel);
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}
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static int mpol_new_nodemask(struct mempolicy *pol, const nodemask_t *nodes)
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{
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if (nodes_empty(*nodes))
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return -EINVAL;
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pol->nodes = *nodes;
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return 0;
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}
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static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes)
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{
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if (nodes_empty(*nodes))
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return -EINVAL;
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nodes_clear(pol->nodes);
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node_set(first_node(*nodes), pol->nodes);
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return 0;
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}
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/*
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* mpol_set_nodemask is called after mpol_new() to set up the nodemask, if
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* any, for the new policy. mpol_new() has already validated the nodes
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* parameter with respect to the policy mode and flags.
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*
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* Must be called holding task's alloc_lock to protect task's mems_allowed
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* and mempolicy. May also be called holding the mmap_lock for write.
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*/
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static int mpol_set_nodemask(struct mempolicy *pol,
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const nodemask_t *nodes, struct nodemask_scratch *nsc)
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{
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int ret;
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/*
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* Default (pol==NULL) resp. local memory policies are not a
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* subject of any remapping. They also do not need any special
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* constructor.
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*/
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if (!pol || pol->mode == MPOL_LOCAL)
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return 0;
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/* Check N_MEMORY */
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nodes_and(nsc->mask1,
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cpuset_current_mems_allowed, node_states[N_MEMORY]);
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VM_BUG_ON(!nodes);
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if (pol->flags & MPOL_F_RELATIVE_NODES)
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mpol_relative_nodemask(&nsc->mask2, nodes, &nsc->mask1);
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else
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nodes_and(nsc->mask2, *nodes, nsc->mask1);
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if (mpol_store_user_nodemask(pol))
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pol->w.user_nodemask = *nodes;
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else
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pol->w.cpuset_mems_allowed = cpuset_current_mems_allowed;
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ret = mpol_ops[pol->mode].create(pol, &nsc->mask2);
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return ret;
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}
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/*
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* This function just creates a new policy, does some check and simple
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* initialization. You must invoke mpol_set_nodemask() to set nodes.
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*/
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static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
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nodemask_t *nodes)
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{
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struct mempolicy *policy;
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pr_debug("setting mode %d flags %d nodes[0] %lx\n",
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mode, flags, nodes ? nodes_addr(*nodes)[0] : NUMA_NO_NODE);
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if (mode == MPOL_DEFAULT) {
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if (nodes && !nodes_empty(*nodes))
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return ERR_PTR(-EINVAL);
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return NULL;
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}
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VM_BUG_ON(!nodes);
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/*
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* MPOL_PREFERRED cannot be used with MPOL_F_STATIC_NODES or
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* MPOL_F_RELATIVE_NODES if the nodemask is empty (local allocation).
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* All other modes require a valid pointer to a non-empty nodemask.
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*/
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if (mode == MPOL_PREFERRED) {
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if (nodes_empty(*nodes)) {
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if (((flags & MPOL_F_STATIC_NODES) ||
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(flags & MPOL_F_RELATIVE_NODES)))
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return ERR_PTR(-EINVAL);
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mode = MPOL_LOCAL;
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}
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} else if (mode == MPOL_LOCAL) {
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if (!nodes_empty(*nodes) ||
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(flags & MPOL_F_STATIC_NODES) ||
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(flags & MPOL_F_RELATIVE_NODES))
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return ERR_PTR(-EINVAL);
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} else if (nodes_empty(*nodes))
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return ERR_PTR(-EINVAL);
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policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
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if (!policy)
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return ERR_PTR(-ENOMEM);
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atomic_set(&policy->refcnt, 1);
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policy->mode = mode;
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policy->flags = flags;
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policy->home_node = NUMA_NO_NODE;
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return policy;
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}
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/* Slow path of a mpol destructor. */
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void __mpol_put(struct mempolicy *p)
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{
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if (!atomic_dec_and_test(&p->refcnt))
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return;
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kmem_cache_free(policy_cache, p);
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}
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static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes)
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{
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}
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static void mpol_rebind_nodemask(struct mempolicy *pol, const nodemask_t *nodes)
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{
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nodemask_t tmp;
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if (pol->flags & MPOL_F_STATIC_NODES)
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nodes_and(tmp, pol->w.user_nodemask, *nodes);
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else if (pol->flags & MPOL_F_RELATIVE_NODES)
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mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
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else {
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nodes_remap(tmp, pol->nodes, pol->w.cpuset_mems_allowed,
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*nodes);
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pol->w.cpuset_mems_allowed = *nodes;
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}
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if (nodes_empty(tmp))
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tmp = *nodes;
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pol->nodes = tmp;
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}
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static void mpol_rebind_preferred(struct mempolicy *pol,
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const nodemask_t *nodes)
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{
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pol->w.cpuset_mems_allowed = *nodes;
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}
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/*
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* mpol_rebind_policy - Migrate a policy to a different set of nodes
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*
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* Per-vma policies are protected by mmap_lock. Allocations using per-task
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* policies are protected by task->mems_allowed_seq to prevent a premature
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* OOM/allocation failure due to parallel nodemask modification.
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*/
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static void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask)
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{
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if (!pol || pol->mode == MPOL_LOCAL)
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return;
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if (!mpol_store_user_nodemask(pol) &&
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nodes_equal(pol->w.cpuset_mems_allowed, *newmask))
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return;
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mpol_ops[pol->mode].rebind(pol, newmask);
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}
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/*
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* Wrapper for mpol_rebind_policy() that just requires task
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* pointer, and updates task mempolicy.
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*
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* Called with task's alloc_lock held.
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*/
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void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
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{
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mpol_rebind_policy(tsk->mempolicy, new);
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}
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/*
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* Rebind each vma in mm to new nodemask.
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*
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* Call holding a reference to mm. Takes mm->mmap_lock during call.
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*/
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void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
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{
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struct vm_area_struct *vma;
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VMA_ITERATOR(vmi, mm, 0);
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mmap_write_lock(mm);
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for_each_vma(vmi, vma) {
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vma_start_write(vma);
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mpol_rebind_policy(vma->vm_policy, new);
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}
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mmap_write_unlock(mm);
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}
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static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
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[MPOL_DEFAULT] = {
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.rebind = mpol_rebind_default,
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},
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[MPOL_INTERLEAVE] = {
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.create = mpol_new_nodemask,
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.rebind = mpol_rebind_nodemask,
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},
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[MPOL_PREFERRED] = {
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.create = mpol_new_preferred,
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.rebind = mpol_rebind_preferred,
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},
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[MPOL_BIND] = {
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.create = mpol_new_nodemask,
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.rebind = mpol_rebind_nodemask,
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},
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[MPOL_LOCAL] = {
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.rebind = mpol_rebind_default,
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},
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[MPOL_PREFERRED_MANY] = {
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.create = mpol_new_nodemask,
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.rebind = mpol_rebind_preferred,
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},
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};
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static int migrate_folio_add(struct folio *folio, struct list_head *foliolist,
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unsigned long flags);
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struct queue_pages {
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struct list_head *pagelist;
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unsigned long flags;
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nodemask_t *nmask;
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unsigned long start;
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unsigned long end;
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struct vm_area_struct *first;
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bool has_unmovable;
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};
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/*
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* Check if the folio's nid is in qp->nmask.
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*
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* If MPOL_MF_INVERT is set in qp->flags, check if the nid is
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* in the invert of qp->nmask.
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*/
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static inline bool queue_folio_required(struct folio *folio,
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struct queue_pages *qp)
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{
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int nid = folio_nid(folio);
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unsigned long flags = qp->flags;
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return node_isset(nid, *qp->nmask) == !(flags & MPOL_MF_INVERT);
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}
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/*
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* queue_folios_pmd() has three possible return values:
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* 0 - folios are placed on the right node or queued successfully, or
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* special page is met, i.e. zero page, or unmovable page is found
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* but continue walking (indicated by queue_pages.has_unmovable).
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* -EIO - is migration entry or only MPOL_MF_STRICT was specified and an
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* existing folio was already on a node that does not follow the
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* policy.
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*/
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static int queue_folios_pmd(pmd_t *pmd, spinlock_t *ptl, unsigned long addr,
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unsigned long end, struct mm_walk *walk)
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__releases(ptl)
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{
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int ret = 0;
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struct folio *folio;
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struct queue_pages *qp = walk->private;
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unsigned long flags;
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if (unlikely(is_pmd_migration_entry(*pmd))) {
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ret = -EIO;
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goto unlock;
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}
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folio = pfn_folio(pmd_pfn(*pmd));
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if (is_huge_zero_page(&folio->page)) {
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walk->action = ACTION_CONTINUE;
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goto unlock;
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}
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if (!queue_folio_required(folio, qp))
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goto unlock;
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flags = qp->flags;
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/* go to folio migration */
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if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
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if (!vma_migratable(walk->vma) ||
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migrate_folio_add(folio, qp->pagelist, flags)) {
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qp->has_unmovable = true;
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goto unlock;
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}
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} else
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ret = -EIO;
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unlock:
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spin_unlock(ptl);
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return ret;
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}
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|
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/*
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* Scan through pages checking if pages follow certain conditions,
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* and move them to the pagelist if they do.
|
|
*
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* queue_folios_pte_range() has three possible return values:
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* 0 - folios are placed on the right node or queued successfully, or
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* special page is met, i.e. zero page, or unmovable page is found
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* but continue walking (indicated by queue_pages.has_unmovable).
|
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* -EIO - only MPOL_MF_STRICT was specified and an existing folio was already
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* on a node that does not follow the policy.
|
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*/
|
|
static int queue_folios_pte_range(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, struct mm_walk *walk)
|
|
{
|
|
struct vm_area_struct *vma = walk->vma;
|
|
struct folio *folio;
|
|
struct queue_pages *qp = walk->private;
|
|
unsigned long flags = qp->flags;
|
|
pte_t *pte, *mapped_pte;
|
|
pte_t ptent;
|
|
spinlock_t *ptl;
|
|
|
|
ptl = pmd_trans_huge_lock(pmd, vma);
|
|
if (ptl)
|
|
return queue_folios_pmd(pmd, ptl, addr, end, walk);
|
|
|
|
mapped_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
|
|
if (!pte) {
|
|
walk->action = ACTION_AGAIN;
|
|
return 0;
|
|
}
|
|
for (; addr != end; pte++, addr += PAGE_SIZE) {
|
|
ptent = ptep_get(pte);
|
|
if (!pte_present(ptent))
|
|
continue;
|
|
folio = vm_normal_folio(vma, addr, ptent);
|
|
if (!folio || folio_is_zone_device(folio))
|
|
continue;
|
|
/*
|
|
* vm_normal_folio() filters out zero pages, but there might
|
|
* still be reserved folios to skip, perhaps in a VDSO.
|
|
*/
|
|
if (folio_test_reserved(folio))
|
|
continue;
|
|
if (!queue_folio_required(folio, qp))
|
|
continue;
|
|
if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
|
|
/*
|
|
* MPOL_MF_STRICT must be specified if we get here.
|
|
* Continue walking vmas due to MPOL_MF_MOVE* flags.
|
|
*/
|
|
if (!vma_migratable(vma))
|
|
qp->has_unmovable = true;
|
|
|
|
/*
|
|
* Do not abort immediately since there may be
|
|
* temporary off LRU pages in the range. Still
|
|
* need migrate other LRU pages.
|
|
*/
|
|
if (migrate_folio_add(folio, qp->pagelist, flags))
|
|
qp->has_unmovable = true;
|
|
} else
|
|
break;
|
|
}
|
|
pte_unmap_unlock(mapped_pte, ptl);
|
|
cond_resched();
|
|
|
|
return addr != end ? -EIO : 0;
|
|
}
|
|
|
|
static int queue_folios_hugetlb(pte_t *pte, unsigned long hmask,
|
|
unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
int ret = 0;
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
struct queue_pages *qp = walk->private;
|
|
unsigned long flags = (qp->flags & MPOL_MF_VALID);
|
|
struct folio *folio;
|
|
spinlock_t *ptl;
|
|
pte_t entry;
|
|
|
|
ptl = huge_pte_lock(hstate_vma(walk->vma), walk->mm, pte);
|
|
entry = huge_ptep_get(pte);
|
|
if (!pte_present(entry))
|
|
goto unlock;
|
|
folio = pfn_folio(pte_pfn(entry));
|
|
if (!queue_folio_required(folio, qp))
|
|
goto unlock;
|
|
|
|
if (flags == MPOL_MF_STRICT) {
|
|
/*
|
|
* STRICT alone means only detecting misplaced folio and no
|
|
* need to further check other vma.
|
|
*/
|
|
ret = -EIO;
|
|
goto unlock;
|
|
}
|
|
|
|
if (!vma_migratable(walk->vma)) {
|
|
/*
|
|
* Must be STRICT with MOVE*, otherwise .test_walk() have
|
|
* stopped walking current vma.
|
|
* Detecting misplaced folio but allow migrating folios which
|
|
* have been queued.
|
|
*/
|
|
qp->has_unmovable = true;
|
|
goto unlock;
|
|
}
|
|
|
|
/*
|
|
* With MPOL_MF_MOVE, we try to migrate only unshared folios. If it
|
|
* is shared it is likely not worth migrating.
|
|
*
|
|
* To check if the folio is shared, ideally we want to make sure
|
|
* every page is mapped to the same process. Doing that is very
|
|
* expensive, so check the estimated mapcount of the folio instead.
|
|
*/
|
|
if (flags & (MPOL_MF_MOVE_ALL) ||
|
|
(flags & MPOL_MF_MOVE && folio_estimated_sharers(folio) == 1 &&
|
|
!hugetlb_pmd_shared(pte))) {
|
|
if (!isolate_hugetlb(folio, qp->pagelist) &&
|
|
(flags & MPOL_MF_STRICT))
|
|
/*
|
|
* Failed to isolate folio but allow migrating pages
|
|
* which have been queued.
|
|
*/
|
|
qp->has_unmovable = true;
|
|
}
|
|
unlock:
|
|
spin_unlock(ptl);
|
|
#else
|
|
BUG();
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
/*
|
|
* This is used to mark a range of virtual addresses to be inaccessible.
|
|
* These are later cleared by a NUMA hinting fault. Depending on these
|
|
* faults, pages may be migrated for better NUMA placement.
|
|
*
|
|
* This is assuming that NUMA faults are handled using PROT_NONE. If
|
|
* an architecture makes a different choice, it will need further
|
|
* changes to the core.
|
|
*/
|
|
unsigned long change_prot_numa(struct vm_area_struct *vma,
|
|
unsigned long addr, unsigned long end)
|
|
{
|
|
struct mmu_gather tlb;
|
|
long nr_updated;
|
|
|
|
tlb_gather_mmu(&tlb, vma->vm_mm);
|
|
|
|
nr_updated = change_protection(&tlb, vma, addr, end, MM_CP_PROT_NUMA);
|
|
if (nr_updated > 0)
|
|
count_vm_numa_events(NUMA_PTE_UPDATES, nr_updated);
|
|
|
|
tlb_finish_mmu(&tlb);
|
|
|
|
return nr_updated;
|
|
}
|
|
#else
|
|
static unsigned long change_prot_numa(struct vm_area_struct *vma,
|
|
unsigned long addr, unsigned long end)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_NUMA_BALANCING */
|
|
|
|
static int queue_pages_test_walk(unsigned long start, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct vm_area_struct *next, *vma = walk->vma;
|
|
struct queue_pages *qp = walk->private;
|
|
unsigned long endvma = vma->vm_end;
|
|
unsigned long flags = qp->flags;
|
|
|
|
/* range check first */
|
|
VM_BUG_ON_VMA(!range_in_vma(vma, start, end), vma);
|
|
|
|
if (!qp->first) {
|
|
qp->first = vma;
|
|
if (!(flags & MPOL_MF_DISCONTIG_OK) &&
|
|
(qp->start < vma->vm_start))
|
|
/* hole at head side of range */
|
|
return -EFAULT;
|
|
}
|
|
next = find_vma(vma->vm_mm, vma->vm_end);
|
|
if (!(flags & MPOL_MF_DISCONTIG_OK) &&
|
|
((vma->vm_end < qp->end) &&
|
|
(!next || vma->vm_end < next->vm_start)))
|
|
/* hole at middle or tail of range */
|
|
return -EFAULT;
|
|
|
|
/*
|
|
* Need check MPOL_MF_STRICT to return -EIO if possible
|
|
* regardless of vma_migratable
|
|
*/
|
|
if (!vma_migratable(vma) &&
|
|
!(flags & MPOL_MF_STRICT))
|
|
return 1;
|
|
|
|
if (endvma > end)
|
|
endvma = end;
|
|
|
|
if (flags & MPOL_MF_LAZY) {
|
|
/* Similar to task_numa_work, skip inaccessible VMAs */
|
|
if (!is_vm_hugetlb_page(vma) && vma_is_accessible(vma) &&
|
|
!(vma->vm_flags & VM_MIXEDMAP))
|
|
change_prot_numa(vma, start, endvma);
|
|
return 1;
|
|
}
|
|
|
|
/* queue pages from current vma */
|
|
if (flags & MPOL_MF_VALID)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static const struct mm_walk_ops queue_pages_walk_ops = {
|
|
.hugetlb_entry = queue_folios_hugetlb,
|
|
.pmd_entry = queue_folios_pte_range,
|
|
.test_walk = queue_pages_test_walk,
|
|
.walk_lock = PGWALK_RDLOCK,
|
|
};
|
|
|
|
static const struct mm_walk_ops queue_pages_lock_vma_walk_ops = {
|
|
.hugetlb_entry = queue_folios_hugetlb,
|
|
.pmd_entry = queue_folios_pte_range,
|
|
.test_walk = queue_pages_test_walk,
|
|
.walk_lock = PGWALK_WRLOCK,
|
|
};
|
|
|
|
/*
|
|
* Walk through page tables and collect pages to be migrated.
|
|
*
|
|
* If pages found in a given range are on a set of nodes (determined by
|
|
* @nodes and @flags,) it's isolated and queued to the pagelist which is
|
|
* passed via @private.
|
|
*
|
|
* queue_pages_range() has three possible return values:
|
|
* 1 - there is unmovable page, but MPOL_MF_MOVE* & MPOL_MF_STRICT were
|
|
* specified.
|
|
* 0 - queue pages successfully or no misplaced page.
|
|
* errno - i.e. misplaced pages with MPOL_MF_STRICT specified (-EIO) or
|
|
* memory range specified by nodemask and maxnode points outside
|
|
* your accessible address space (-EFAULT)
|
|
*/
|
|
static int
|
|
queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end,
|
|
nodemask_t *nodes, unsigned long flags,
|
|
struct list_head *pagelist, bool lock_vma)
|
|
{
|
|
int err;
|
|
struct queue_pages qp = {
|
|
.pagelist = pagelist,
|
|
.flags = flags,
|
|
.nmask = nodes,
|
|
.start = start,
|
|
.end = end,
|
|
.first = NULL,
|
|
.has_unmovable = false,
|
|
};
|
|
const struct mm_walk_ops *ops = lock_vma ?
|
|
&queue_pages_lock_vma_walk_ops : &queue_pages_walk_ops;
|
|
|
|
err = walk_page_range(mm, start, end, ops, &qp);
|
|
|
|
if (qp.has_unmovable)
|
|
err = 1;
|
|
if (!qp.first)
|
|
/* whole range in hole */
|
|
err = -EFAULT;
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Apply policy to a single VMA
|
|
* This must be called with the mmap_lock held for writing.
|
|
*/
|
|
static int vma_replace_policy(struct vm_area_struct *vma,
|
|
struct mempolicy *pol)
|
|
{
|
|
int err;
|
|
struct mempolicy *old;
|
|
struct mempolicy *new;
|
|
|
|
vma_assert_write_locked(vma);
|
|
|
|
pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n",
|
|
vma->vm_start, vma->vm_end, vma->vm_pgoff,
|
|
vma->vm_ops, vma->vm_file,
|
|
vma->vm_ops ? vma->vm_ops->set_policy : NULL);
|
|
|
|
new = mpol_dup(pol);
|
|
if (IS_ERR(new))
|
|
return PTR_ERR(new);
|
|
|
|
if (vma->vm_ops && vma->vm_ops->set_policy) {
|
|
err = vma->vm_ops->set_policy(vma, new);
|
|
if (err)
|
|
goto err_out;
|
|
}
|
|
|
|
old = vma->vm_policy;
|
|
vma->vm_policy = new; /* protected by mmap_lock */
|
|
mpol_put(old);
|
|
|
|
return 0;
|
|
err_out:
|
|
mpol_put(new);
|
|
return err;
|
|
}
|
|
|
|
/* Split or merge the VMA (if required) and apply the new policy */
|
|
static int mbind_range(struct vma_iterator *vmi, struct vm_area_struct *vma,
|
|
struct vm_area_struct **prev, unsigned long start,
|
|
unsigned long end, struct mempolicy *new_pol)
|
|
{
|
|
struct vm_area_struct *merged;
|
|
unsigned long vmstart, vmend;
|
|
pgoff_t pgoff;
|
|
int err;
|
|
|
|
vmend = min(end, vma->vm_end);
|
|
if (start > vma->vm_start) {
|
|
*prev = vma;
|
|
vmstart = start;
|
|
} else {
|
|
vmstart = vma->vm_start;
|
|
}
|
|
|
|
if (mpol_equal(vma_policy(vma), new_pol)) {
|
|
*prev = vma;
|
|
return 0;
|
|
}
|
|
|
|
pgoff = vma->vm_pgoff + ((vmstart - vma->vm_start) >> PAGE_SHIFT);
|
|
merged = vma_merge(vmi, vma->vm_mm, *prev, vmstart, vmend, vma->vm_flags,
|
|
vma->anon_vma, vma->vm_file, pgoff, new_pol,
|
|
vma->vm_userfaultfd_ctx, anon_vma_name(vma));
|
|
if (merged) {
|
|
*prev = merged;
|
|
return vma_replace_policy(merged, new_pol);
|
|
}
|
|
|
|
if (vma->vm_start != vmstart) {
|
|
err = split_vma(vmi, vma, vmstart, 1);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
if (vma->vm_end != vmend) {
|
|
err = split_vma(vmi, vma, vmend, 0);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
*prev = vma;
|
|
return vma_replace_policy(vma, new_pol);
|
|
}
|
|
|
|
/* Set the process memory policy */
|
|
static long do_set_mempolicy(unsigned short mode, unsigned short flags,
|
|
nodemask_t *nodes)
|
|
{
|
|
struct mempolicy *new, *old;
|
|
NODEMASK_SCRATCH(scratch);
|
|
int ret;
|
|
|
|
if (!scratch)
|
|
return -ENOMEM;
|
|
|
|
new = mpol_new(mode, flags, nodes);
|
|
if (IS_ERR(new)) {
|
|
ret = PTR_ERR(new);
|
|
goto out;
|
|
}
|
|
|
|
task_lock(current);
|
|
ret = mpol_set_nodemask(new, nodes, scratch);
|
|
if (ret) {
|
|
task_unlock(current);
|
|
mpol_put(new);
|
|
goto out;
|
|
}
|
|
|
|
old = current->mempolicy;
|
|
current->mempolicy = new;
|
|
if (new && new->mode == MPOL_INTERLEAVE)
|
|
current->il_prev = MAX_NUMNODES-1;
|
|
task_unlock(current);
|
|
mpol_put(old);
|
|
ret = 0;
|
|
out:
|
|
NODEMASK_SCRATCH_FREE(scratch);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Return nodemask for policy for get_mempolicy() query
|
|
*
|
|
* Called with task's alloc_lock held
|
|
*/
|
|
static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
|
|
{
|
|
nodes_clear(*nodes);
|
|
if (p == &default_policy)
|
|
return;
|
|
|
|
switch (p->mode) {
|
|
case MPOL_BIND:
|
|
case MPOL_INTERLEAVE:
|
|
case MPOL_PREFERRED:
|
|
case MPOL_PREFERRED_MANY:
|
|
*nodes = p->nodes;
|
|
break;
|
|
case MPOL_LOCAL:
|
|
/* return empty node mask for local allocation */
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
static int lookup_node(struct mm_struct *mm, unsigned long addr)
|
|
{
|
|
struct page *p = NULL;
|
|
int ret;
|
|
|
|
ret = get_user_pages_fast(addr & PAGE_MASK, 1, 0, &p);
|
|
if (ret > 0) {
|
|
ret = page_to_nid(p);
|
|
put_page(p);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/* Retrieve NUMA policy */
|
|
static long do_get_mempolicy(int *policy, nodemask_t *nmask,
|
|
unsigned long addr, unsigned long flags)
|
|
{
|
|
int err;
|
|
struct mm_struct *mm = current->mm;
|
|
struct vm_area_struct *vma = NULL;
|
|
struct mempolicy *pol = current->mempolicy, *pol_refcount = NULL;
|
|
|
|
if (flags &
|
|
~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
|
|
return -EINVAL;
|
|
|
|
if (flags & MPOL_F_MEMS_ALLOWED) {
|
|
if (flags & (MPOL_F_NODE|MPOL_F_ADDR))
|
|
return -EINVAL;
|
|
*policy = 0; /* just so it's initialized */
|
|
task_lock(current);
|
|
*nmask = cpuset_current_mems_allowed;
|
|
task_unlock(current);
|
|
return 0;
|
|
}
|
|
|
|
if (flags & MPOL_F_ADDR) {
|
|
/*
|
|
* Do NOT fall back to task policy if the
|
|
* vma/shared policy at addr is NULL. We
|
|
* want to return MPOL_DEFAULT in this case.
|
|
*/
|
|
mmap_read_lock(mm);
|
|
vma = vma_lookup(mm, addr);
|
|
if (!vma) {
|
|
mmap_read_unlock(mm);
|
|
return -EFAULT;
|
|
}
|
|
if (vma->vm_ops && vma->vm_ops->get_policy)
|
|
pol = vma->vm_ops->get_policy(vma, addr);
|
|
else
|
|
pol = vma->vm_policy;
|
|
} else if (addr)
|
|
return -EINVAL;
|
|
|
|
if (!pol)
|
|
pol = &default_policy; /* indicates default behavior */
|
|
|
|
if (flags & MPOL_F_NODE) {
|
|
if (flags & MPOL_F_ADDR) {
|
|
/*
|
|
* Take a refcount on the mpol, because we are about to
|
|
* drop the mmap_lock, after which only "pol" remains
|
|
* valid, "vma" is stale.
|
|
*/
|
|
pol_refcount = pol;
|
|
vma = NULL;
|
|
mpol_get(pol);
|
|
mmap_read_unlock(mm);
|
|
err = lookup_node(mm, addr);
|
|
if (err < 0)
|
|
goto out;
|
|
*policy = err;
|
|
} else if (pol == current->mempolicy &&
|
|
pol->mode == MPOL_INTERLEAVE) {
|
|
*policy = next_node_in(current->il_prev, pol->nodes);
|
|
} else {
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
} else {
|
|
*policy = pol == &default_policy ? MPOL_DEFAULT :
|
|
pol->mode;
|
|
/*
|
|
* Internal mempolicy flags must be masked off before exposing
|
|
* the policy to userspace.
|
|
*/
|
|
*policy |= (pol->flags & MPOL_MODE_FLAGS);
|
|
}
|
|
|
|
err = 0;
|
|
if (nmask) {
|
|
if (mpol_store_user_nodemask(pol)) {
|
|
*nmask = pol->w.user_nodemask;
|
|
} else {
|
|
task_lock(current);
|
|
get_policy_nodemask(pol, nmask);
|
|
task_unlock(current);
|
|
}
|
|
}
|
|
|
|
out:
|
|
mpol_cond_put(pol);
|
|
if (vma)
|
|
mmap_read_unlock(mm);
|
|
if (pol_refcount)
|
|
mpol_put(pol_refcount);
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_MIGRATION
|
|
static int migrate_folio_add(struct folio *folio, struct list_head *foliolist,
|
|
unsigned long flags)
|
|
{
|
|
/*
|
|
* We try to migrate only unshared folios. If it is shared it
|
|
* is likely not worth migrating.
|
|
*
|
|
* To check if the folio is shared, ideally we want to make sure
|
|
* every page is mapped to the same process. Doing that is very
|
|
* expensive, so check the estimated mapcount of the folio instead.
|
|
*/
|
|
if ((flags & MPOL_MF_MOVE_ALL) || folio_estimated_sharers(folio) == 1) {
|
|
if (folio_isolate_lru(folio)) {
|
|
list_add_tail(&folio->lru, foliolist);
|
|
node_stat_mod_folio(folio,
|
|
NR_ISOLATED_ANON + folio_is_file_lru(folio),
|
|
folio_nr_pages(folio));
|
|
} else if (flags & MPOL_MF_STRICT) {
|
|
/*
|
|
* Non-movable folio may reach here. And, there may be
|
|
* temporary off LRU folios or non-LRU movable folios.
|
|
* Treat them as unmovable folios since they can't be
|
|
* isolated, so they can't be moved at the moment. It
|
|
* should return -EIO for this case too.
|
|
*/
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Migrate pages from one node to a target node.
|
|
* Returns error or the number of pages not migrated.
|
|
*/
|
|
static int migrate_to_node(struct mm_struct *mm, int source, int dest,
|
|
int flags)
|
|
{
|
|
nodemask_t nmask;
|
|
struct vm_area_struct *vma;
|
|
LIST_HEAD(pagelist);
|
|
int err = 0;
|
|
struct migration_target_control mtc = {
|
|
.nid = dest,
|
|
.gfp_mask = GFP_HIGHUSER_MOVABLE | __GFP_THISNODE,
|
|
};
|
|
|
|
nodes_clear(nmask);
|
|
node_set(source, nmask);
|
|
|
|
/*
|
|
* This does not "check" the range but isolates all pages that
|
|
* need migration. Between passing in the full user address
|
|
* space range and MPOL_MF_DISCONTIG_OK, this call can not fail.
|
|
*/
|
|
vma = find_vma(mm, 0);
|
|
VM_BUG_ON(!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)));
|
|
queue_pages_range(mm, vma->vm_start, mm->task_size, &nmask,
|
|
flags | MPOL_MF_DISCONTIG_OK, &pagelist, false);
|
|
|
|
if (!list_empty(&pagelist)) {
|
|
err = migrate_pages(&pagelist, alloc_migration_target, NULL,
|
|
(unsigned long)&mtc, MIGRATE_SYNC, MR_SYSCALL, NULL);
|
|
if (err)
|
|
putback_movable_pages(&pagelist);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Move pages between the two nodesets so as to preserve the physical
|
|
* layout as much as possible.
|
|
*
|
|
* Returns the number of page that could not be moved.
|
|
*/
|
|
int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
|
|
const nodemask_t *to, int flags)
|
|
{
|
|
int busy = 0;
|
|
int err = 0;
|
|
nodemask_t tmp;
|
|
|
|
lru_cache_disable();
|
|
|
|
mmap_read_lock(mm);
|
|
|
|
/*
|
|
* Find a 'source' bit set in 'tmp' whose corresponding 'dest'
|
|
* bit in 'to' is not also set in 'tmp'. Clear the found 'source'
|
|
* bit in 'tmp', and return that <source, dest> pair for migration.
|
|
* The pair of nodemasks 'to' and 'from' define the map.
|
|
*
|
|
* If no pair of bits is found that way, fallback to picking some
|
|
* pair of 'source' and 'dest' bits that are not the same. If the
|
|
* 'source' and 'dest' bits are the same, this represents a node
|
|
* that will be migrating to itself, so no pages need move.
|
|
*
|
|
* If no bits are left in 'tmp', or if all remaining bits left
|
|
* in 'tmp' correspond to the same bit in 'to', return false
|
|
* (nothing left to migrate).
|
|
*
|
|
* This lets us pick a pair of nodes to migrate between, such that
|
|
* if possible the dest node is not already occupied by some other
|
|
* source node, minimizing the risk of overloading the memory on a
|
|
* node that would happen if we migrated incoming memory to a node
|
|
* before migrating outgoing memory source that same node.
|
|
*
|
|
* A single scan of tmp is sufficient. As we go, we remember the
|
|
* most recent <s, d> pair that moved (s != d). If we find a pair
|
|
* that not only moved, but what's better, moved to an empty slot
|
|
* (d is not set in tmp), then we break out then, with that pair.
|
|
* Otherwise when we finish scanning from_tmp, we at least have the
|
|
* most recent <s, d> pair that moved. If we get all the way through
|
|
* the scan of tmp without finding any node that moved, much less
|
|
* moved to an empty node, then there is nothing left worth migrating.
|
|
*/
|
|
|
|
tmp = *from;
|
|
while (!nodes_empty(tmp)) {
|
|
int s, d;
|
|
int source = NUMA_NO_NODE;
|
|
int dest = 0;
|
|
|
|
for_each_node_mask(s, tmp) {
|
|
|
|
/*
|
|
* do_migrate_pages() tries to maintain the relative
|
|
* node relationship of the pages established between
|
|
* threads and memory areas.
|
|
*
|
|
* However if the number of source nodes is not equal to
|
|
* the number of destination nodes we can not preserve
|
|
* this node relative relationship. In that case, skip
|
|
* copying memory from a node that is in the destination
|
|
* mask.
|
|
*
|
|
* Example: [2,3,4] -> [3,4,5] moves everything.
|
|
* [0-7] - > [3,4,5] moves only 0,1,2,6,7.
|
|
*/
|
|
|
|
if ((nodes_weight(*from) != nodes_weight(*to)) &&
|
|
(node_isset(s, *to)))
|
|
continue;
|
|
|
|
d = node_remap(s, *from, *to);
|
|
if (s == d)
|
|
continue;
|
|
|
|
source = s; /* Node moved. Memorize */
|
|
dest = d;
|
|
|
|
/* dest not in remaining from nodes? */
|
|
if (!node_isset(dest, tmp))
|
|
break;
|
|
}
|
|
if (source == NUMA_NO_NODE)
|
|
break;
|
|
|
|
node_clear(source, tmp);
|
|
err = migrate_to_node(mm, source, dest, flags);
|
|
if (err > 0)
|
|
busy += err;
|
|
if (err < 0)
|
|
break;
|
|
}
|
|
mmap_read_unlock(mm);
|
|
|
|
lru_cache_enable();
|
|
if (err < 0)
|
|
return err;
|
|
return busy;
|
|
|
|
}
|
|
|
|
/*
|
|
* Allocate a new page for page migration based on vma policy.
|
|
* Start by assuming the page is mapped by the same vma as contains @start.
|
|
* Search forward from there, if not. N.B., this assumes that the
|
|
* list of pages handed to migrate_pages()--which is how we get here--
|
|
* is in virtual address order.
|
|
*/
|
|
static struct folio *new_folio(struct folio *src, unsigned long start)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
unsigned long address;
|
|
VMA_ITERATOR(vmi, current->mm, start);
|
|
gfp_t gfp = GFP_HIGHUSER_MOVABLE | __GFP_RETRY_MAYFAIL;
|
|
|
|
for_each_vma(vmi, vma) {
|
|
address = page_address_in_vma(&src->page, vma);
|
|
if (address != -EFAULT)
|
|
break;
|
|
}
|
|
|
|
if (folio_test_hugetlb(src)) {
|
|
return alloc_hugetlb_folio_vma(folio_hstate(src),
|
|
vma, address);
|
|
}
|
|
|
|
if (folio_test_large(src))
|
|
gfp = GFP_TRANSHUGE;
|
|
|
|
/*
|
|
* if !vma, vma_alloc_folio() will use task or system default policy
|
|
*/
|
|
return vma_alloc_folio(gfp, folio_order(src), vma, address,
|
|
folio_test_large(src));
|
|
}
|
|
#else
|
|
|
|
static int migrate_folio_add(struct folio *folio, struct list_head *foliolist,
|
|
unsigned long flags)
|
|
{
|
|
return -EIO;
|
|
}
|
|
|
|
int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
|
|
const nodemask_t *to, int flags)
|
|
{
|
|
return -ENOSYS;
|
|
}
|
|
|
|
static struct folio *new_folio(struct folio *src, unsigned long start)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
static long do_mbind(unsigned long start, unsigned long len,
|
|
unsigned short mode, unsigned short mode_flags,
|
|
nodemask_t *nmask, unsigned long flags)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
struct vm_area_struct *vma, *prev;
|
|
struct vma_iterator vmi;
|
|
struct mempolicy *new;
|
|
unsigned long end;
|
|
int err;
|
|
int ret;
|
|
LIST_HEAD(pagelist);
|
|
|
|
if (flags & ~(unsigned long)MPOL_MF_VALID)
|
|
return -EINVAL;
|
|
if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
|
|
return -EPERM;
|
|
|
|
if (start & ~PAGE_MASK)
|
|
return -EINVAL;
|
|
|
|
if (mode == MPOL_DEFAULT)
|
|
flags &= ~MPOL_MF_STRICT;
|
|
|
|
len = PAGE_ALIGN(len);
|
|
end = start + len;
|
|
|
|
if (end < start)
|
|
return -EINVAL;
|
|
if (end == start)
|
|
return 0;
|
|
|
|
new = mpol_new(mode, mode_flags, nmask);
|
|
if (IS_ERR(new))
|
|
return PTR_ERR(new);
|
|
|
|
if (flags & MPOL_MF_LAZY)
|
|
new->flags |= MPOL_F_MOF;
|
|
|
|
/*
|
|
* If we are using the default policy then operation
|
|
* on discontinuous address spaces is okay after all
|
|
*/
|
|
if (!new)
|
|
flags |= MPOL_MF_DISCONTIG_OK;
|
|
|
|
pr_debug("mbind %lx-%lx mode:%d flags:%d nodes:%lx\n",
|
|
start, start + len, mode, mode_flags,
|
|
nmask ? nodes_addr(*nmask)[0] : NUMA_NO_NODE);
|
|
|
|
if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
|
|
|
|
lru_cache_disable();
|
|
}
|
|
{
|
|
NODEMASK_SCRATCH(scratch);
|
|
if (scratch) {
|
|
mmap_write_lock(mm);
|
|
err = mpol_set_nodemask(new, nmask, scratch);
|
|
if (err)
|
|
mmap_write_unlock(mm);
|
|
} else
|
|
err = -ENOMEM;
|
|
NODEMASK_SCRATCH_FREE(scratch);
|
|
}
|
|
if (err)
|
|
goto mpol_out;
|
|
|
|
/*
|
|
* Lock the VMAs before scanning for pages to migrate, to ensure we don't
|
|
* miss a concurrently inserted page.
|
|
*/
|
|
ret = queue_pages_range(mm, start, end, nmask,
|
|
flags | MPOL_MF_INVERT, &pagelist, true);
|
|
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto up_out;
|
|
}
|
|
|
|
vma_iter_init(&vmi, mm, start);
|
|
prev = vma_prev(&vmi);
|
|
for_each_vma_range(vmi, vma, end) {
|
|
err = mbind_range(&vmi, vma, &prev, start, end, new);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
if (!err) {
|
|
int nr_failed = 0;
|
|
|
|
if (!list_empty(&pagelist)) {
|
|
WARN_ON_ONCE(flags & MPOL_MF_LAZY);
|
|
nr_failed = migrate_pages(&pagelist, new_folio, NULL,
|
|
start, MIGRATE_SYNC, MR_MEMPOLICY_MBIND, NULL);
|
|
if (nr_failed)
|
|
putback_movable_pages(&pagelist);
|
|
}
|
|
|
|
if (((ret > 0) || nr_failed) && (flags & MPOL_MF_STRICT))
|
|
err = -EIO;
|
|
} else {
|
|
up_out:
|
|
if (!list_empty(&pagelist))
|
|
putback_movable_pages(&pagelist);
|
|
}
|
|
|
|
mmap_write_unlock(mm);
|
|
mpol_out:
|
|
mpol_put(new);
|
|
if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
|
|
lru_cache_enable();
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* User space interface with variable sized bitmaps for nodelists.
|
|
*/
|
|
static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask,
|
|
unsigned long maxnode)
|
|
{
|
|
unsigned long nlongs = BITS_TO_LONGS(maxnode);
|
|
int ret;
|
|
|
|
if (in_compat_syscall())
|
|
ret = compat_get_bitmap(mask,
|
|
(const compat_ulong_t __user *)nmask,
|
|
maxnode);
|
|
else
|
|
ret = copy_from_user(mask, nmask,
|
|
nlongs * sizeof(unsigned long));
|
|
|
|
if (ret)
|
|
return -EFAULT;
|
|
|
|
if (maxnode % BITS_PER_LONG)
|
|
mask[nlongs - 1] &= (1UL << (maxnode % BITS_PER_LONG)) - 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Copy a node mask from user space. */
|
|
static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
|
|
unsigned long maxnode)
|
|
{
|
|
--maxnode;
|
|
nodes_clear(*nodes);
|
|
if (maxnode == 0 || !nmask)
|
|
return 0;
|
|
if (maxnode > PAGE_SIZE*BITS_PER_BYTE)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* When the user specified more nodes than supported just check
|
|
* if the non supported part is all zero, one word at a time,
|
|
* starting at the end.
|
|
*/
|
|
while (maxnode > MAX_NUMNODES) {
|
|
unsigned long bits = min_t(unsigned long, maxnode, BITS_PER_LONG);
|
|
unsigned long t;
|
|
|
|
if (get_bitmap(&t, &nmask[(maxnode - 1) / BITS_PER_LONG], bits))
|
|
return -EFAULT;
|
|
|
|
if (maxnode - bits >= MAX_NUMNODES) {
|
|
maxnode -= bits;
|
|
} else {
|
|
maxnode = MAX_NUMNODES;
|
|
t &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1);
|
|
}
|
|
if (t)
|
|
return -EINVAL;
|
|
}
|
|
|
|
return get_bitmap(nodes_addr(*nodes), nmask, maxnode);
|
|
}
|
|
|
|
/* Copy a kernel node mask to user space */
|
|
static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
|
|
nodemask_t *nodes)
|
|
{
|
|
unsigned long copy = ALIGN(maxnode-1, 64) / 8;
|
|
unsigned int nbytes = BITS_TO_LONGS(nr_node_ids) * sizeof(long);
|
|
bool compat = in_compat_syscall();
|
|
|
|
if (compat)
|
|
nbytes = BITS_TO_COMPAT_LONGS(nr_node_ids) * sizeof(compat_long_t);
|
|
|
|
if (copy > nbytes) {
|
|
if (copy > PAGE_SIZE)
|
|
return -EINVAL;
|
|
if (clear_user((char __user *)mask + nbytes, copy - nbytes))
|
|
return -EFAULT;
|
|
copy = nbytes;
|
|
maxnode = nr_node_ids;
|
|
}
|
|
|
|
if (compat)
|
|
return compat_put_bitmap((compat_ulong_t __user *)mask,
|
|
nodes_addr(*nodes), maxnode);
|
|
|
|
return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
|
|
}
|
|
|
|
/* Basic parameter sanity check used by both mbind() and set_mempolicy() */
|
|
static inline int sanitize_mpol_flags(int *mode, unsigned short *flags)
|
|
{
|
|
*flags = *mode & MPOL_MODE_FLAGS;
|
|
*mode &= ~MPOL_MODE_FLAGS;
|
|
|
|
if ((unsigned int)(*mode) >= MPOL_MAX)
|
|
return -EINVAL;
|
|
if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES))
|
|
return -EINVAL;
|
|
if (*flags & MPOL_F_NUMA_BALANCING) {
|
|
if (*mode != MPOL_BIND)
|
|
return -EINVAL;
|
|
*flags |= (MPOL_F_MOF | MPOL_F_MORON);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static long kernel_mbind(unsigned long start, unsigned long len,
|
|
unsigned long mode, const unsigned long __user *nmask,
|
|
unsigned long maxnode, unsigned int flags)
|
|
{
|
|
unsigned short mode_flags;
|
|
nodemask_t nodes;
|
|
int lmode = mode;
|
|
int err;
|
|
|
|
start = untagged_addr(start);
|
|
err = sanitize_mpol_flags(&lmode, &mode_flags);
|
|
if (err)
|
|
return err;
|
|
|
|
err = get_nodes(&nodes, nmask, maxnode);
|
|
if (err)
|
|
return err;
|
|
|
|
return do_mbind(start, len, lmode, mode_flags, &nodes, flags);
|
|
}
|
|
|
|
SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, len,
|
|
unsigned long, home_node, unsigned long, flags)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
struct vm_area_struct *vma, *prev;
|
|
struct mempolicy *new, *old;
|
|
unsigned long end;
|
|
int err = -ENOENT;
|
|
VMA_ITERATOR(vmi, mm, start);
|
|
|
|
start = untagged_addr(start);
|
|
if (start & ~PAGE_MASK)
|
|
return -EINVAL;
|
|
/*
|
|
* flags is used for future extension if any.
|
|
*/
|
|
if (flags != 0)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Check home_node is online to avoid accessing uninitialized
|
|
* NODE_DATA.
|
|
*/
|
|
if (home_node >= MAX_NUMNODES || !node_online(home_node))
|
|
return -EINVAL;
|
|
|
|
len = PAGE_ALIGN(len);
|
|
end = start + len;
|
|
|
|
if (end < start)
|
|
return -EINVAL;
|
|
if (end == start)
|
|
return 0;
|
|
mmap_write_lock(mm);
|
|
prev = vma_prev(&vmi);
|
|
for_each_vma_range(vmi, vma, end) {
|
|
/*
|
|
* If any vma in the range got policy other than MPOL_BIND
|
|
* or MPOL_PREFERRED_MANY we return error. We don't reset
|
|
* the home node for vmas we already updated before.
|
|
*/
|
|
old = vma_policy(vma);
|
|
if (!old) {
|
|
prev = vma;
|
|
continue;
|
|
}
|
|
if (old->mode != MPOL_BIND && old->mode != MPOL_PREFERRED_MANY) {
|
|
err = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
new = mpol_dup(old);
|
|
if (IS_ERR(new)) {
|
|
err = PTR_ERR(new);
|
|
break;
|
|
}
|
|
|
|
vma_start_write(vma);
|
|
new->home_node = home_node;
|
|
err = mbind_range(&vmi, vma, &prev, start, end, new);
|
|
mpol_put(new);
|
|
if (err)
|
|
break;
|
|
}
|
|
mmap_write_unlock(mm);
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len,
|
|
unsigned long, mode, const unsigned long __user *, nmask,
|
|
unsigned long, maxnode, unsigned int, flags)
|
|
{
|
|
return kernel_mbind(start, len, mode, nmask, maxnode, flags);
|
|
}
|
|
|
|
/* Set the process memory policy */
|
|
static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
|
|
unsigned long maxnode)
|
|
{
|
|
unsigned short mode_flags;
|
|
nodemask_t nodes;
|
|
int lmode = mode;
|
|
int err;
|
|
|
|
err = sanitize_mpol_flags(&lmode, &mode_flags);
|
|
if (err)
|
|
return err;
|
|
|
|
err = get_nodes(&nodes, nmask, maxnode);
|
|
if (err)
|
|
return err;
|
|
|
|
return do_set_mempolicy(lmode, mode_flags, &nodes);
|
|
}
|
|
|
|
SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask,
|
|
unsigned long, maxnode)
|
|
{
|
|
return kernel_set_mempolicy(mode, nmask, maxnode);
|
|
}
|
|
|
|
static int kernel_migrate_pages(pid_t pid, unsigned long maxnode,
|
|
const unsigned long __user *old_nodes,
|
|
const unsigned long __user *new_nodes)
|
|
{
|
|
struct mm_struct *mm = NULL;
|
|
struct task_struct *task;
|
|
nodemask_t task_nodes;
|
|
int err;
|
|
nodemask_t *old;
|
|
nodemask_t *new;
|
|
NODEMASK_SCRATCH(scratch);
|
|
|
|
if (!scratch)
|
|
return -ENOMEM;
|
|
|
|
old = &scratch->mask1;
|
|
new = &scratch->mask2;
|
|
|
|
err = get_nodes(old, old_nodes, maxnode);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = get_nodes(new, new_nodes, maxnode);
|
|
if (err)
|
|
goto out;
|
|
|
|
/* Find the mm_struct */
|
|
rcu_read_lock();
|
|
task = pid ? find_task_by_vpid(pid) : current;
|
|
if (!task) {
|
|
rcu_read_unlock();
|
|
err = -ESRCH;
|
|
goto out;
|
|
}
|
|
get_task_struct(task);
|
|
|
|
err = -EINVAL;
|
|
|
|
/*
|
|
* Check if this process has the right to modify the specified process.
|
|
* Use the regular "ptrace_may_access()" checks.
|
|
*/
|
|
if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) {
|
|
rcu_read_unlock();
|
|
err = -EPERM;
|
|
goto out_put;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
task_nodes = cpuset_mems_allowed(task);
|
|
/* Is the user allowed to access the target nodes? */
|
|
if (!nodes_subset(*new, task_nodes) && !capable(CAP_SYS_NICE)) {
|
|
err = -EPERM;
|
|
goto out_put;
|
|
}
|
|
|
|
task_nodes = cpuset_mems_allowed(current);
|
|
nodes_and(*new, *new, task_nodes);
|
|
if (nodes_empty(*new))
|
|
goto out_put;
|
|
|
|
err = security_task_movememory(task);
|
|
if (err)
|
|
goto out_put;
|
|
|
|
mm = get_task_mm(task);
|
|
put_task_struct(task);
|
|
|
|
if (!mm) {
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
err = do_migrate_pages(mm, old, new,
|
|
capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE);
|
|
|
|
mmput(mm);
|
|
out:
|
|
NODEMASK_SCRATCH_FREE(scratch);
|
|
|
|
return err;
|
|
|
|
out_put:
|
|
put_task_struct(task);
|
|
goto out;
|
|
|
|
}
|
|
|
|
SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode,
|
|
const unsigned long __user *, old_nodes,
|
|
const unsigned long __user *, new_nodes)
|
|
{
|
|
return kernel_migrate_pages(pid, maxnode, old_nodes, new_nodes);
|
|
}
|
|
|
|
|
|
/* Retrieve NUMA policy */
|
|
static int kernel_get_mempolicy(int __user *policy,
|
|
unsigned long __user *nmask,
|
|
unsigned long maxnode,
|
|
unsigned long addr,
|
|
unsigned long flags)
|
|
{
|
|
int err;
|
|
int pval;
|
|
nodemask_t nodes;
|
|
|
|
if (nmask != NULL && maxnode < nr_node_ids)
|
|
return -EINVAL;
|
|
|
|
addr = untagged_addr(addr);
|
|
|
|
err = do_get_mempolicy(&pval, &nodes, addr, flags);
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
if (policy && put_user(pval, policy))
|
|
return -EFAULT;
|
|
|
|
if (nmask)
|
|
err = copy_nodes_to_user(nmask, maxnode, &nodes);
|
|
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
|
|
unsigned long __user *, nmask, unsigned long, maxnode,
|
|
unsigned long, addr, unsigned long, flags)
|
|
{
|
|
return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags);
|
|
}
|
|
|
|
bool vma_migratable(struct vm_area_struct *vma)
|
|
{
|
|
if (vma->vm_flags & (VM_IO | VM_PFNMAP))
|
|
return false;
|
|
|
|
/*
|
|
* DAX device mappings require predictable access latency, so avoid
|
|
* incurring periodic faults.
|
|
*/
|
|
if (vma_is_dax(vma))
|
|
return false;
|
|
|
|
if (is_vm_hugetlb_page(vma) &&
|
|
!hugepage_migration_supported(hstate_vma(vma)))
|
|
return false;
|
|
|
|
/*
|
|
* Migration allocates pages in the highest zone. If we cannot
|
|
* do so then migration (at least from node to node) is not
|
|
* possible.
|
|
*/
|
|
if (vma->vm_file &&
|
|
gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping))
|
|
< policy_zone)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,
|
|
unsigned long addr)
|
|
{
|
|
struct mempolicy *pol = NULL;
|
|
|
|
if (vma) {
|
|
if (vma->vm_ops && vma->vm_ops->get_policy) {
|
|
pol = vma->vm_ops->get_policy(vma, addr);
|
|
} else if (vma->vm_policy) {
|
|
pol = vma->vm_policy;
|
|
|
|
/*
|
|
* shmem_alloc_page() passes MPOL_F_SHARED policy with
|
|
* a pseudo vma whose vma->vm_ops=NULL. Take a reference
|
|
* count on these policies which will be dropped by
|
|
* mpol_cond_put() later
|
|
*/
|
|
if (mpol_needs_cond_ref(pol))
|
|
mpol_get(pol);
|
|
}
|
|
}
|
|
|
|
return pol;
|
|
}
|
|
|
|
/*
|
|
* get_vma_policy(@vma, @addr)
|
|
* @vma: virtual memory area whose policy is sought
|
|
* @addr: address in @vma for shared policy lookup
|
|
*
|
|
* Returns effective policy for a VMA at specified address.
|
|
* Falls back to current->mempolicy or system default policy, as necessary.
|
|
* Shared policies [those marked as MPOL_F_SHARED] require an extra reference
|
|
* count--added by the get_policy() vm_op, as appropriate--to protect against
|
|
* freeing by another task. It is the caller's responsibility to free the
|
|
* extra reference for shared policies.
|
|
*/
|
|
static struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
|
|
unsigned long addr)
|
|
{
|
|
struct mempolicy *pol = __get_vma_policy(vma, addr);
|
|
|
|
if (!pol)
|
|
pol = get_task_policy(current);
|
|
|
|
return pol;
|
|
}
|
|
|
|
bool vma_policy_mof(struct vm_area_struct *vma)
|
|
{
|
|
struct mempolicy *pol;
|
|
|
|
if (vma->vm_ops && vma->vm_ops->get_policy) {
|
|
bool ret = false;
|
|
|
|
pol = vma->vm_ops->get_policy(vma, vma->vm_start);
|
|
if (pol && (pol->flags & MPOL_F_MOF))
|
|
ret = true;
|
|
mpol_cond_put(pol);
|
|
|
|
return ret;
|
|
}
|
|
|
|
pol = vma->vm_policy;
|
|
if (!pol)
|
|
pol = get_task_policy(current);
|
|
|
|
return pol->flags & MPOL_F_MOF;
|
|
}
|
|
|
|
bool apply_policy_zone(struct mempolicy *policy, enum zone_type zone)
|
|
{
|
|
enum zone_type dynamic_policy_zone = policy_zone;
|
|
|
|
BUG_ON(dynamic_policy_zone == ZONE_MOVABLE);
|
|
|
|
/*
|
|
* if policy->nodes has movable memory only,
|
|
* we apply policy when gfp_zone(gfp) = ZONE_MOVABLE only.
|
|
*
|
|
* policy->nodes is intersect with node_states[N_MEMORY].
|
|
* so if the following test fails, it implies
|
|
* policy->nodes has movable memory only.
|
|
*/
|
|
if (!nodes_intersects(policy->nodes, node_states[N_HIGH_MEMORY]))
|
|
dynamic_policy_zone = ZONE_MOVABLE;
|
|
|
|
return zone >= dynamic_policy_zone;
|
|
}
|
|
|
|
/*
|
|
* Return a nodemask representing a mempolicy for filtering nodes for
|
|
* page allocation
|
|
*/
|
|
nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy)
|
|
{
|
|
int mode = policy->mode;
|
|
|
|
/* Lower zones don't get a nodemask applied for MPOL_BIND */
|
|
if (unlikely(mode == MPOL_BIND) &&
|
|
apply_policy_zone(policy, gfp_zone(gfp)) &&
|
|
cpuset_nodemask_valid_mems_allowed(&policy->nodes))
|
|
return &policy->nodes;
|
|
|
|
if (mode == MPOL_PREFERRED_MANY)
|
|
return &policy->nodes;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Return the preferred node id for 'prefer' mempolicy, and return
|
|
* the given id for all other policies.
|
|
*
|
|
* policy_node() is always coupled with policy_nodemask(), which
|
|
* secures the nodemask limit for 'bind' and 'prefer-many' policy.
|
|
*/
|
|
static int policy_node(gfp_t gfp, struct mempolicy *policy, int nd)
|
|
{
|
|
if (policy->mode == MPOL_PREFERRED) {
|
|
nd = first_node(policy->nodes);
|
|
} else {
|
|
/*
|
|
* __GFP_THISNODE shouldn't even be used with the bind policy
|
|
* because we might easily break the expectation to stay on the
|
|
* requested node and not break the policy.
|
|
*/
|
|
WARN_ON_ONCE(policy->mode == MPOL_BIND && (gfp & __GFP_THISNODE));
|
|
}
|
|
|
|
if ((policy->mode == MPOL_BIND ||
|
|
policy->mode == MPOL_PREFERRED_MANY) &&
|
|
policy->home_node != NUMA_NO_NODE)
|
|
return policy->home_node;
|
|
|
|
return nd;
|
|
}
|
|
|
|
/* Do dynamic interleaving for a process */
|
|
static unsigned interleave_nodes(struct mempolicy *policy)
|
|
{
|
|
unsigned next;
|
|
struct task_struct *me = current;
|
|
|
|
next = next_node_in(me->il_prev, policy->nodes);
|
|
if (next < MAX_NUMNODES)
|
|
me->il_prev = next;
|
|
return next;
|
|
}
|
|
|
|
/*
|
|
* Depending on the memory policy provide a node from which to allocate the
|
|
* next slab entry.
|
|
*/
|
|
unsigned int mempolicy_slab_node(void)
|
|
{
|
|
struct mempolicy *policy;
|
|
int node = numa_mem_id();
|
|
|
|
if (!in_task())
|
|
return node;
|
|
|
|
policy = current->mempolicy;
|
|
if (!policy)
|
|
return node;
|
|
|
|
switch (policy->mode) {
|
|
case MPOL_PREFERRED:
|
|
return first_node(policy->nodes);
|
|
|
|
case MPOL_INTERLEAVE:
|
|
return interleave_nodes(policy);
|
|
|
|
case MPOL_BIND:
|
|
case MPOL_PREFERRED_MANY:
|
|
{
|
|
struct zoneref *z;
|
|
|
|
/*
|
|
* Follow bind policy behavior and start allocation at the
|
|
* first node.
|
|
*/
|
|
struct zonelist *zonelist;
|
|
enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL);
|
|
zonelist = &NODE_DATA(node)->node_zonelists[ZONELIST_FALLBACK];
|
|
z = first_zones_zonelist(zonelist, highest_zoneidx,
|
|
&policy->nodes);
|
|
return z->zone ? zone_to_nid(z->zone) : node;
|
|
}
|
|
case MPOL_LOCAL:
|
|
return node;
|
|
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Do static interleaving for a VMA with known offset @n. Returns the n'th
|
|
* node in pol->nodes (starting from n=0), wrapping around if n exceeds the
|
|
* number of present nodes.
|
|
*/
|
|
static unsigned offset_il_node(struct mempolicy *pol, unsigned long n)
|
|
{
|
|
nodemask_t nodemask = pol->nodes;
|
|
unsigned int target, nnodes;
|
|
int i;
|
|
int nid;
|
|
/*
|
|
* The barrier will stabilize the nodemask in a register or on
|
|
* the stack so that it will stop changing under the code.
|
|
*
|
|
* Between first_node() and next_node(), pol->nodes could be changed
|
|
* by other threads. So we put pol->nodes in a local stack.
|
|
*/
|
|
barrier();
|
|
|
|
nnodes = nodes_weight(nodemask);
|
|
if (!nnodes)
|
|
return numa_node_id();
|
|
target = (unsigned int)n % nnodes;
|
|
nid = first_node(nodemask);
|
|
for (i = 0; i < target; i++)
|
|
nid = next_node(nid, nodemask);
|
|
return nid;
|
|
}
|
|
|
|
/* Determine a node number for interleave */
|
|
static inline unsigned interleave_nid(struct mempolicy *pol,
|
|
struct vm_area_struct *vma, unsigned long addr, int shift)
|
|
{
|
|
if (vma) {
|
|
unsigned long off;
|
|
|
|
/*
|
|
* for small pages, there is no difference between
|
|
* shift and PAGE_SHIFT, so the bit-shift is safe.
|
|
* for huge pages, since vm_pgoff is in units of small
|
|
* pages, we need to shift off the always 0 bits to get
|
|
* a useful offset.
|
|
*/
|
|
BUG_ON(shift < PAGE_SHIFT);
|
|
off = vma->vm_pgoff >> (shift - PAGE_SHIFT);
|
|
off += (addr - vma->vm_start) >> shift;
|
|
return offset_il_node(pol, off);
|
|
} else
|
|
return interleave_nodes(pol);
|
|
}
|
|
|
|
#ifdef CONFIG_HUGETLBFS
|
|
/*
|
|
* huge_node(@vma, @addr, @gfp_flags, @mpol)
|
|
* @vma: virtual memory area whose policy is sought
|
|
* @addr: address in @vma for shared policy lookup and interleave policy
|
|
* @gfp_flags: for requested zone
|
|
* @mpol: pointer to mempolicy pointer for reference counted mempolicy
|
|
* @nodemask: pointer to nodemask pointer for 'bind' and 'prefer-many' policy
|
|
*
|
|
* Returns a nid suitable for a huge page allocation and a pointer
|
|
* to the struct mempolicy for conditional unref after allocation.
|
|
* If the effective policy is 'bind' or 'prefer-many', returns a pointer
|
|
* to the mempolicy's @nodemask for filtering the zonelist.
|
|
*
|
|
* Must be protected by read_mems_allowed_begin()
|
|
*/
|
|
int huge_node(struct vm_area_struct *vma, unsigned long addr, gfp_t gfp_flags,
|
|
struct mempolicy **mpol, nodemask_t **nodemask)
|
|
{
|
|
int nid;
|
|
int mode;
|
|
|
|
*mpol = get_vma_policy(vma, addr);
|
|
*nodemask = NULL;
|
|
mode = (*mpol)->mode;
|
|
|
|
if (unlikely(mode == MPOL_INTERLEAVE)) {
|
|
nid = interleave_nid(*mpol, vma, addr,
|
|
huge_page_shift(hstate_vma(vma)));
|
|
} else {
|
|
nid = policy_node(gfp_flags, *mpol, numa_node_id());
|
|
if (mode == MPOL_BIND || mode == MPOL_PREFERRED_MANY)
|
|
*nodemask = &(*mpol)->nodes;
|
|
}
|
|
return nid;
|
|
}
|
|
|
|
/*
|
|
* init_nodemask_of_mempolicy
|
|
*
|
|
* If the current task's mempolicy is "default" [NULL], return 'false'
|
|
* to indicate default policy. Otherwise, extract the policy nodemask
|
|
* for 'bind' or 'interleave' policy into the argument nodemask, or
|
|
* initialize the argument nodemask to contain the single node for
|
|
* 'preferred' or 'local' policy and return 'true' to indicate presence
|
|
* of non-default mempolicy.
|
|
*
|
|
* We don't bother with reference counting the mempolicy [mpol_get/put]
|
|
* because the current task is examining it's own mempolicy and a task's
|
|
* mempolicy is only ever changed by the task itself.
|
|
*
|
|
* N.B., it is the caller's responsibility to free a returned nodemask.
|
|
*/
|
|
bool init_nodemask_of_mempolicy(nodemask_t *mask)
|
|
{
|
|
struct mempolicy *mempolicy;
|
|
|
|
if (!(mask && current->mempolicy))
|
|
return false;
|
|
|
|
task_lock(current);
|
|
mempolicy = current->mempolicy;
|
|
switch (mempolicy->mode) {
|
|
case MPOL_PREFERRED:
|
|
case MPOL_PREFERRED_MANY:
|
|
case MPOL_BIND:
|
|
case MPOL_INTERLEAVE:
|
|
*mask = mempolicy->nodes;
|
|
break;
|
|
|
|
case MPOL_LOCAL:
|
|
init_nodemask_of_node(mask, numa_node_id());
|
|
break;
|
|
|
|
default:
|
|
BUG();
|
|
}
|
|
task_unlock(current);
|
|
|
|
return true;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* mempolicy_in_oom_domain
|
|
*
|
|
* If tsk's mempolicy is "bind", check for intersection between mask and
|
|
* the policy nodemask. Otherwise, return true for all other policies
|
|
* including "interleave", as a tsk with "interleave" policy may have
|
|
* memory allocated from all nodes in system.
|
|
*
|
|
* Takes task_lock(tsk) to prevent freeing of its mempolicy.
|
|
*/
|
|
bool mempolicy_in_oom_domain(struct task_struct *tsk,
|
|
const nodemask_t *mask)
|
|
{
|
|
struct mempolicy *mempolicy;
|
|
bool ret = true;
|
|
|
|
if (!mask)
|
|
return ret;
|
|
|
|
task_lock(tsk);
|
|
mempolicy = tsk->mempolicy;
|
|
if (mempolicy && mempolicy->mode == MPOL_BIND)
|
|
ret = nodes_intersects(mempolicy->nodes, *mask);
|
|
task_unlock(tsk);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Allocate a page in interleaved policy.
|
|
Own path because it needs to do special accounting. */
|
|
static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
|
|
unsigned nid)
|
|
{
|
|
struct page *page;
|
|
|
|
page = __alloc_pages(gfp, order, nid, NULL);
|
|
/* skip NUMA_INTERLEAVE_HIT counter update if numa stats is disabled */
|
|
if (!static_branch_likely(&vm_numa_stat_key))
|
|
return page;
|
|
if (page && page_to_nid(page) == nid) {
|
|
preempt_disable();
|
|
__count_numa_event(page_zone(page), NUMA_INTERLEAVE_HIT);
|
|
preempt_enable();
|
|
}
|
|
return page;
|
|
}
|
|
|
|
static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order,
|
|
int nid, struct mempolicy *pol)
|
|
{
|
|
struct page *page;
|
|
gfp_t preferred_gfp;
|
|
|
|
/*
|
|
* This is a two pass approach. The first pass will only try the
|
|
* preferred nodes but skip the direct reclaim and allow the
|
|
* allocation to fail, while the second pass will try all the
|
|
* nodes in system.
|
|
*/
|
|
preferred_gfp = gfp | __GFP_NOWARN;
|
|
preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL);
|
|
page = __alloc_pages(preferred_gfp, order, nid, &pol->nodes);
|
|
if (!page)
|
|
page = __alloc_pages(gfp, order, nid, NULL);
|
|
|
|
return page;
|
|
}
|
|
|
|
/**
|
|
* vma_alloc_folio - Allocate a folio for a VMA.
|
|
* @gfp: GFP flags.
|
|
* @order: Order of the folio.
|
|
* @vma: Pointer to VMA or NULL if not available.
|
|
* @addr: Virtual address of the allocation. Must be inside @vma.
|
|
* @hugepage: For hugepages try only the preferred node if possible.
|
|
*
|
|
* Allocate a folio for a specific address in @vma, using the appropriate
|
|
* NUMA policy. When @vma is not NULL the caller must hold the mmap_lock
|
|
* of the mm_struct of the VMA to prevent it from going away. Should be
|
|
* used for all allocations for folios that will be mapped into user space.
|
|
*
|
|
* Return: The folio on success or NULL if allocation fails.
|
|
*/
|
|
struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
|
|
unsigned long addr, bool hugepage)
|
|
{
|
|
struct mempolicy *pol;
|
|
int node = numa_node_id();
|
|
struct folio *folio;
|
|
int preferred_nid;
|
|
nodemask_t *nmask;
|
|
|
|
pol = get_vma_policy(vma, addr);
|
|
|
|
if (pol->mode == MPOL_INTERLEAVE) {
|
|
struct page *page;
|
|
unsigned nid;
|
|
|
|
nid = interleave_nid(pol, vma, addr, PAGE_SHIFT + order);
|
|
mpol_cond_put(pol);
|
|
gfp |= __GFP_COMP;
|
|
page = alloc_page_interleave(gfp, order, nid);
|
|
folio = (struct folio *)page;
|
|
if (folio && order > 1)
|
|
folio_prep_large_rmappable(folio);
|
|
goto out;
|
|
}
|
|
|
|
if (pol->mode == MPOL_PREFERRED_MANY) {
|
|
struct page *page;
|
|
|
|
node = policy_node(gfp, pol, node);
|
|
gfp |= __GFP_COMP;
|
|
page = alloc_pages_preferred_many(gfp, order, node, pol);
|
|
mpol_cond_put(pol);
|
|
folio = (struct folio *)page;
|
|
if (folio && order > 1)
|
|
folio_prep_large_rmappable(folio);
|
|
goto out;
|
|
}
|
|
|
|
if (unlikely(IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hugepage)) {
|
|
int hpage_node = node;
|
|
|
|
/*
|
|
* For hugepage allocation and non-interleave policy which
|
|
* allows the current node (or other explicitly preferred
|
|
* node) we only try to allocate from the current/preferred
|
|
* node and don't fall back to other nodes, as the cost of
|
|
* remote accesses would likely offset THP benefits.
|
|
*
|
|
* If the policy is interleave or does not allow the current
|
|
* node in its nodemask, we allocate the standard way.
|
|
*/
|
|
if (pol->mode == MPOL_PREFERRED)
|
|
hpage_node = first_node(pol->nodes);
|
|
|
|
nmask = policy_nodemask(gfp, pol);
|
|
if (!nmask || node_isset(hpage_node, *nmask)) {
|
|
mpol_cond_put(pol);
|
|
/*
|
|
* First, try to allocate THP only on local node, but
|
|
* don't reclaim unnecessarily, just compact.
|
|
*/
|
|
folio = __folio_alloc_node(gfp | __GFP_THISNODE |
|
|
__GFP_NORETRY, order, hpage_node);
|
|
|
|
/*
|
|
* If hugepage allocations are configured to always
|
|
* synchronous compact or the vma has been madvised
|
|
* to prefer hugepage backing, retry allowing remote
|
|
* memory with both reclaim and compact as well.
|
|
*/
|
|
if (!folio && (gfp & __GFP_DIRECT_RECLAIM))
|
|
folio = __folio_alloc(gfp, order, hpage_node,
|
|
nmask);
|
|
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
nmask = policy_nodemask(gfp, pol);
|
|
preferred_nid = policy_node(gfp, pol, node);
|
|
folio = __folio_alloc(gfp, order, preferred_nid, nmask);
|
|
mpol_cond_put(pol);
|
|
out:
|
|
return folio;
|
|
}
|
|
EXPORT_SYMBOL(vma_alloc_folio);
|
|
|
|
/**
|
|
* alloc_pages - Allocate pages.
|
|
* @gfp: GFP flags.
|
|
* @order: Power of two of number of pages to allocate.
|
|
*
|
|
* Allocate 1 << @order contiguous pages. The physical address of the
|
|
* first page is naturally aligned (eg an order-3 allocation will be aligned
|
|
* to a multiple of 8 * PAGE_SIZE bytes). The NUMA policy of the current
|
|
* process is honoured when in process context.
|
|
*
|
|
* Context: Can be called from any context, providing the appropriate GFP
|
|
* flags are used.
|
|
* Return: The page on success or NULL if allocation fails.
|
|
*/
|
|
struct page *alloc_pages(gfp_t gfp, unsigned order)
|
|
{
|
|
struct mempolicy *pol = &default_policy;
|
|
struct page *page;
|
|
|
|
if (!in_interrupt() && !(gfp & __GFP_THISNODE))
|
|
pol = get_task_policy(current);
|
|
|
|
/*
|
|
* No reference counting needed for current->mempolicy
|
|
* nor system default_policy
|
|
*/
|
|
if (pol->mode == MPOL_INTERLEAVE)
|
|
page = alloc_page_interleave(gfp, order, interleave_nodes(pol));
|
|
else if (pol->mode == MPOL_PREFERRED_MANY)
|
|
page = alloc_pages_preferred_many(gfp, order,
|
|
policy_node(gfp, pol, numa_node_id()), pol);
|
|
else
|
|
page = __alloc_pages(gfp, order,
|
|
policy_node(gfp, pol, numa_node_id()),
|
|
policy_nodemask(gfp, pol));
|
|
|
|
return page;
|
|
}
|
|
EXPORT_SYMBOL(alloc_pages);
|
|
|
|
struct folio *folio_alloc(gfp_t gfp, unsigned order)
|
|
{
|
|
struct page *page = alloc_pages(gfp | __GFP_COMP, order);
|
|
struct folio *folio = (struct folio *)page;
|
|
|
|
if (folio && order > 1)
|
|
folio_prep_large_rmappable(folio);
|
|
return folio;
|
|
}
|
|
EXPORT_SYMBOL(folio_alloc);
|
|
|
|
static unsigned long alloc_pages_bulk_array_interleave(gfp_t gfp,
|
|
struct mempolicy *pol, unsigned long nr_pages,
|
|
struct page **page_array)
|
|
{
|
|
int nodes;
|
|
unsigned long nr_pages_per_node;
|
|
int delta;
|
|
int i;
|
|
unsigned long nr_allocated;
|
|
unsigned long total_allocated = 0;
|
|
|
|
nodes = nodes_weight(pol->nodes);
|
|
nr_pages_per_node = nr_pages / nodes;
|
|
delta = nr_pages - nodes * nr_pages_per_node;
|
|
|
|
for (i = 0; i < nodes; i++) {
|
|
if (delta) {
|
|
nr_allocated = __alloc_pages_bulk(gfp,
|
|
interleave_nodes(pol), NULL,
|
|
nr_pages_per_node + 1, NULL,
|
|
page_array);
|
|
delta--;
|
|
} else {
|
|
nr_allocated = __alloc_pages_bulk(gfp,
|
|
interleave_nodes(pol), NULL,
|
|
nr_pages_per_node, NULL, page_array);
|
|
}
|
|
|
|
page_array += nr_allocated;
|
|
total_allocated += nr_allocated;
|
|
}
|
|
|
|
return total_allocated;
|
|
}
|
|
|
|
static unsigned long alloc_pages_bulk_array_preferred_many(gfp_t gfp, int nid,
|
|
struct mempolicy *pol, unsigned long nr_pages,
|
|
struct page **page_array)
|
|
{
|
|
gfp_t preferred_gfp;
|
|
unsigned long nr_allocated = 0;
|
|
|
|
preferred_gfp = gfp | __GFP_NOWARN;
|
|
preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL);
|
|
|
|
nr_allocated = __alloc_pages_bulk(preferred_gfp, nid, &pol->nodes,
|
|
nr_pages, NULL, page_array);
|
|
|
|
if (nr_allocated < nr_pages)
|
|
nr_allocated += __alloc_pages_bulk(gfp, numa_node_id(), NULL,
|
|
nr_pages - nr_allocated, NULL,
|
|
page_array + nr_allocated);
|
|
return nr_allocated;
|
|
}
|
|
|
|
/* alloc pages bulk and mempolicy should be considered at the
|
|
* same time in some situation such as vmalloc.
|
|
*
|
|
* It can accelerate memory allocation especially interleaving
|
|
* allocate memory.
|
|
*/
|
|
unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp,
|
|
unsigned long nr_pages, struct page **page_array)
|
|
{
|
|
struct mempolicy *pol = &default_policy;
|
|
|
|
if (!in_interrupt() && !(gfp & __GFP_THISNODE))
|
|
pol = get_task_policy(current);
|
|
|
|
if (pol->mode == MPOL_INTERLEAVE)
|
|
return alloc_pages_bulk_array_interleave(gfp, pol,
|
|
nr_pages, page_array);
|
|
|
|
if (pol->mode == MPOL_PREFERRED_MANY)
|
|
return alloc_pages_bulk_array_preferred_many(gfp,
|
|
numa_node_id(), pol, nr_pages, page_array);
|
|
|
|
return __alloc_pages_bulk(gfp, policy_node(gfp, pol, numa_node_id()),
|
|
policy_nodemask(gfp, pol), nr_pages, NULL,
|
|
page_array);
|
|
}
|
|
|
|
int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
|
|
{
|
|
struct mempolicy *pol = mpol_dup(vma_policy(src));
|
|
|
|
if (IS_ERR(pol))
|
|
return PTR_ERR(pol);
|
|
dst->vm_policy = pol;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it
|
|
* rebinds the mempolicy its copying by calling mpol_rebind_policy()
|
|
* with the mems_allowed returned by cpuset_mems_allowed(). This
|
|
* keeps mempolicies cpuset relative after its cpuset moves. See
|
|
* further kernel/cpuset.c update_nodemask().
|
|
*
|
|
* current's mempolicy may be rebinded by the other task(the task that changes
|
|
* cpuset's mems), so we needn't do rebind work for current task.
|
|
*/
|
|
|
|
/* Slow path of a mempolicy duplicate */
|
|
struct mempolicy *__mpol_dup(struct mempolicy *old)
|
|
{
|
|
struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
|
|
|
|
if (!new)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
/* task's mempolicy is protected by alloc_lock */
|
|
if (old == current->mempolicy) {
|
|
task_lock(current);
|
|
*new = *old;
|
|
task_unlock(current);
|
|
} else
|
|
*new = *old;
|
|
|
|
if (current_cpuset_is_being_rebound()) {
|
|
nodemask_t mems = cpuset_mems_allowed(current);
|
|
mpol_rebind_policy(new, &mems);
|
|
}
|
|
atomic_set(&new->refcnt, 1);
|
|
return new;
|
|
}
|
|
|
|
/* Slow path of a mempolicy comparison */
|
|
bool __mpol_equal(struct mempolicy *a, struct mempolicy *b)
|
|
{
|
|
if (!a || !b)
|
|
return false;
|
|
if (a->mode != b->mode)
|
|
return false;
|
|
if (a->flags != b->flags)
|
|
return false;
|
|
if (a->home_node != b->home_node)
|
|
return false;
|
|
if (mpol_store_user_nodemask(a))
|
|
if (!nodes_equal(a->w.user_nodemask, b->w.user_nodemask))
|
|
return false;
|
|
|
|
switch (a->mode) {
|
|
case MPOL_BIND:
|
|
case MPOL_INTERLEAVE:
|
|
case MPOL_PREFERRED:
|
|
case MPOL_PREFERRED_MANY:
|
|
return !!nodes_equal(a->nodes, b->nodes);
|
|
case MPOL_LOCAL:
|
|
return true;
|
|
default:
|
|
BUG();
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Shared memory backing store policy support.
|
|
*
|
|
* Remember policies even when nobody has shared memory mapped.
|
|
* The policies are kept in Red-Black tree linked from the inode.
|
|
* They are protected by the sp->lock rwlock, which should be held
|
|
* for any accesses to the tree.
|
|
*/
|
|
|
|
/*
|
|
* lookup first element intersecting start-end. Caller holds sp->lock for
|
|
* reading or for writing
|
|
*/
|
|
static struct sp_node *
|
|
sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end)
|
|
{
|
|
struct rb_node *n = sp->root.rb_node;
|
|
|
|
while (n) {
|
|
struct sp_node *p = rb_entry(n, struct sp_node, nd);
|
|
|
|
if (start >= p->end)
|
|
n = n->rb_right;
|
|
else if (end <= p->start)
|
|
n = n->rb_left;
|
|
else
|
|
break;
|
|
}
|
|
if (!n)
|
|
return NULL;
|
|
for (;;) {
|
|
struct sp_node *w = NULL;
|
|
struct rb_node *prev = rb_prev(n);
|
|
if (!prev)
|
|
break;
|
|
w = rb_entry(prev, struct sp_node, nd);
|
|
if (w->end <= start)
|
|
break;
|
|
n = prev;
|
|
}
|
|
return rb_entry(n, struct sp_node, nd);
|
|
}
|
|
|
|
/*
|
|
* Insert a new shared policy into the list. Caller holds sp->lock for
|
|
* writing.
|
|
*/
|
|
static void sp_insert(struct shared_policy *sp, struct sp_node *new)
|
|
{
|
|
struct rb_node **p = &sp->root.rb_node;
|
|
struct rb_node *parent = NULL;
|
|
struct sp_node *nd;
|
|
|
|
while (*p) {
|
|
parent = *p;
|
|
nd = rb_entry(parent, struct sp_node, nd);
|
|
if (new->start < nd->start)
|
|
p = &(*p)->rb_left;
|
|
else if (new->end > nd->end)
|
|
p = &(*p)->rb_right;
|
|
else
|
|
BUG();
|
|
}
|
|
rb_link_node(&new->nd, parent, p);
|
|
rb_insert_color(&new->nd, &sp->root);
|
|
pr_debug("inserting %lx-%lx: %d\n", new->start, new->end,
|
|
new->policy ? new->policy->mode : 0);
|
|
}
|
|
|
|
/* Find shared policy intersecting idx */
|
|
struct mempolicy *
|
|
mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
|
|
{
|
|
struct mempolicy *pol = NULL;
|
|
struct sp_node *sn;
|
|
|
|
if (!sp->root.rb_node)
|
|
return NULL;
|
|
read_lock(&sp->lock);
|
|
sn = sp_lookup(sp, idx, idx+1);
|
|
if (sn) {
|
|
mpol_get(sn->policy);
|
|
pol = sn->policy;
|
|
}
|
|
read_unlock(&sp->lock);
|
|
return pol;
|
|
}
|
|
|
|
static void sp_free(struct sp_node *n)
|
|
{
|
|
mpol_put(n->policy);
|
|
kmem_cache_free(sn_cache, n);
|
|
}
|
|
|
|
/**
|
|
* mpol_misplaced - check whether current page node is valid in policy
|
|
*
|
|
* @page: page to be checked
|
|
* @vma: vm area where page mapped
|
|
* @addr: virtual address where page mapped
|
|
*
|
|
* Lookup current policy node id for vma,addr and "compare to" page's
|
|
* node id. Policy determination "mimics" alloc_page_vma().
|
|
* Called from fault path where we know the vma and faulting address.
|
|
*
|
|
* Return: NUMA_NO_NODE if the page is in a node that is valid for this
|
|
* policy, or a suitable node ID to allocate a replacement page from.
|
|
*/
|
|
int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long addr)
|
|
{
|
|
struct mempolicy *pol;
|
|
struct zoneref *z;
|
|
int curnid = page_to_nid(page);
|
|
unsigned long pgoff;
|
|
int thiscpu = raw_smp_processor_id();
|
|
int thisnid = cpu_to_node(thiscpu);
|
|
int polnid = NUMA_NO_NODE;
|
|
int ret = NUMA_NO_NODE;
|
|
|
|
pol = get_vma_policy(vma, addr);
|
|
if (!(pol->flags & MPOL_F_MOF))
|
|
goto out;
|
|
|
|
switch (pol->mode) {
|
|
case MPOL_INTERLEAVE:
|
|
pgoff = vma->vm_pgoff;
|
|
pgoff += (addr - vma->vm_start) >> PAGE_SHIFT;
|
|
polnid = offset_il_node(pol, pgoff);
|
|
break;
|
|
|
|
case MPOL_PREFERRED:
|
|
if (node_isset(curnid, pol->nodes))
|
|
goto out;
|
|
polnid = first_node(pol->nodes);
|
|
break;
|
|
|
|
case MPOL_LOCAL:
|
|
polnid = numa_node_id();
|
|
break;
|
|
|
|
case MPOL_BIND:
|
|
/* Optimize placement among multiple nodes via NUMA balancing */
|
|
if (pol->flags & MPOL_F_MORON) {
|
|
if (node_isset(thisnid, pol->nodes))
|
|
break;
|
|
goto out;
|
|
}
|
|
fallthrough;
|
|
|
|
case MPOL_PREFERRED_MANY:
|
|
/*
|
|
* use current page if in policy nodemask,
|
|
* else select nearest allowed node, if any.
|
|
* If no allowed nodes, use current [!misplaced].
|
|
*/
|
|
if (node_isset(curnid, pol->nodes))
|
|
goto out;
|
|
z = first_zones_zonelist(
|
|
node_zonelist(numa_node_id(), GFP_HIGHUSER),
|
|
gfp_zone(GFP_HIGHUSER),
|
|
&pol->nodes);
|
|
polnid = zone_to_nid(z->zone);
|
|
break;
|
|
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
/* Migrate the page towards the node whose CPU is referencing it */
|
|
if (pol->flags & MPOL_F_MORON) {
|
|
polnid = thisnid;
|
|
|
|
if (!should_numa_migrate_memory(current, page, curnid, thiscpu))
|
|
goto out;
|
|
}
|
|
|
|
if (curnid != polnid)
|
|
ret = polnid;
|
|
out:
|
|
mpol_cond_put(pol);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Drop the (possibly final) reference to task->mempolicy. It needs to be
|
|
* dropped after task->mempolicy is set to NULL so that any allocation done as
|
|
* part of its kmem_cache_free(), such as by KASAN, doesn't reference a freed
|
|
* policy.
|
|
*/
|
|
void mpol_put_task_policy(struct task_struct *task)
|
|
{
|
|
struct mempolicy *pol;
|
|
|
|
task_lock(task);
|
|
pol = task->mempolicy;
|
|
task->mempolicy = NULL;
|
|
task_unlock(task);
|
|
mpol_put(pol);
|
|
}
|
|
|
|
static void sp_delete(struct shared_policy *sp, struct sp_node *n)
|
|
{
|
|
pr_debug("deleting %lx-l%lx\n", n->start, n->end);
|
|
rb_erase(&n->nd, &sp->root);
|
|
sp_free(n);
|
|
}
|
|
|
|
static void sp_node_init(struct sp_node *node, unsigned long start,
|
|
unsigned long end, struct mempolicy *pol)
|
|
{
|
|
node->start = start;
|
|
node->end = end;
|
|
node->policy = pol;
|
|
}
|
|
|
|
static struct sp_node *sp_alloc(unsigned long start, unsigned long end,
|
|
struct mempolicy *pol)
|
|
{
|
|
struct sp_node *n;
|
|
struct mempolicy *newpol;
|
|
|
|
n = kmem_cache_alloc(sn_cache, GFP_KERNEL);
|
|
if (!n)
|
|
return NULL;
|
|
|
|
newpol = mpol_dup(pol);
|
|
if (IS_ERR(newpol)) {
|
|
kmem_cache_free(sn_cache, n);
|
|
return NULL;
|
|
}
|
|
newpol->flags |= MPOL_F_SHARED;
|
|
sp_node_init(n, start, end, newpol);
|
|
|
|
return n;
|
|
}
|
|
|
|
/* Replace a policy range. */
|
|
static int shared_policy_replace(struct shared_policy *sp, unsigned long start,
|
|
unsigned long end, struct sp_node *new)
|
|
{
|
|
struct sp_node *n;
|
|
struct sp_node *n_new = NULL;
|
|
struct mempolicy *mpol_new = NULL;
|
|
int ret = 0;
|
|
|
|
restart:
|
|
write_lock(&sp->lock);
|
|
n = sp_lookup(sp, start, end);
|
|
/* Take care of old policies in the same range. */
|
|
while (n && n->start < end) {
|
|
struct rb_node *next = rb_next(&n->nd);
|
|
if (n->start >= start) {
|
|
if (n->end <= end)
|
|
sp_delete(sp, n);
|
|
else
|
|
n->start = end;
|
|
} else {
|
|
/* Old policy spanning whole new range. */
|
|
if (n->end > end) {
|
|
if (!n_new)
|
|
goto alloc_new;
|
|
|
|
*mpol_new = *n->policy;
|
|
atomic_set(&mpol_new->refcnt, 1);
|
|
sp_node_init(n_new, end, n->end, mpol_new);
|
|
n->end = start;
|
|
sp_insert(sp, n_new);
|
|
n_new = NULL;
|
|
mpol_new = NULL;
|
|
break;
|
|
} else
|
|
n->end = start;
|
|
}
|
|
if (!next)
|
|
break;
|
|
n = rb_entry(next, struct sp_node, nd);
|
|
}
|
|
if (new)
|
|
sp_insert(sp, new);
|
|
write_unlock(&sp->lock);
|
|
ret = 0;
|
|
|
|
err_out:
|
|
if (mpol_new)
|
|
mpol_put(mpol_new);
|
|
if (n_new)
|
|
kmem_cache_free(sn_cache, n_new);
|
|
|
|
return ret;
|
|
|
|
alloc_new:
|
|
write_unlock(&sp->lock);
|
|
ret = -ENOMEM;
|
|
n_new = kmem_cache_alloc(sn_cache, GFP_KERNEL);
|
|
if (!n_new)
|
|
goto err_out;
|
|
mpol_new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
|
|
if (!mpol_new)
|
|
goto err_out;
|
|
atomic_set(&mpol_new->refcnt, 1);
|
|
goto restart;
|
|
}
|
|
|
|
/**
|
|
* mpol_shared_policy_init - initialize shared policy for inode
|
|
* @sp: pointer to inode shared policy
|
|
* @mpol: struct mempolicy to install
|
|
*
|
|
* Install non-NULL @mpol in inode's shared policy rb-tree.
|
|
* On entry, the current task has a reference on a non-NULL @mpol.
|
|
* This must be released on exit.
|
|
* This is called at get_inode() calls and we can use GFP_KERNEL.
|
|
*/
|
|
void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
|
|
{
|
|
int ret;
|
|
|
|
sp->root = RB_ROOT; /* empty tree == default mempolicy */
|
|
rwlock_init(&sp->lock);
|
|
|
|
if (mpol) {
|
|
struct vm_area_struct pvma;
|
|
struct mempolicy *new;
|
|
NODEMASK_SCRATCH(scratch);
|
|
|
|
if (!scratch)
|
|
goto put_mpol;
|
|
/* contextualize the tmpfs mount point mempolicy */
|
|
new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
|
|
if (IS_ERR(new))
|
|
goto free_scratch; /* no valid nodemask intersection */
|
|
|
|
task_lock(current);
|
|
ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch);
|
|
task_unlock(current);
|
|
if (ret)
|
|
goto put_new;
|
|
|
|
/* Create pseudo-vma that contains just the policy */
|
|
vma_init(&pvma, NULL);
|
|
pvma.vm_end = TASK_SIZE; /* policy covers entire file */
|
|
mpol_set_shared_policy(sp, &pvma, new); /* adds ref */
|
|
|
|
put_new:
|
|
mpol_put(new); /* drop initial ref */
|
|
free_scratch:
|
|
NODEMASK_SCRATCH_FREE(scratch);
|
|
put_mpol:
|
|
mpol_put(mpol); /* drop our incoming ref on sb mpol */
|
|
}
|
|
}
|
|
|
|
int mpol_set_shared_policy(struct shared_policy *info,
|
|
struct vm_area_struct *vma, struct mempolicy *npol)
|
|
{
|
|
int err;
|
|
struct sp_node *new = NULL;
|
|
unsigned long sz = vma_pages(vma);
|
|
|
|
pr_debug("set_shared_policy %lx sz %lu %d %d %lx\n",
|
|
vma->vm_pgoff,
|
|
sz, npol ? npol->mode : -1,
|
|
npol ? npol->flags : -1,
|
|
npol ? nodes_addr(npol->nodes)[0] : NUMA_NO_NODE);
|
|
|
|
if (npol) {
|
|
new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol);
|
|
if (!new)
|
|
return -ENOMEM;
|
|
}
|
|
err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new);
|
|
if (err && new)
|
|
sp_free(new);
|
|
return err;
|
|
}
|
|
|
|
/* Free a backing policy store on inode delete. */
|
|
void mpol_free_shared_policy(struct shared_policy *p)
|
|
{
|
|
struct sp_node *n;
|
|
struct rb_node *next;
|
|
|
|
if (!p->root.rb_node)
|
|
return;
|
|
write_lock(&p->lock);
|
|
next = rb_first(&p->root);
|
|
while (next) {
|
|
n = rb_entry(next, struct sp_node, nd);
|
|
next = rb_next(&n->nd);
|
|
sp_delete(p, n);
|
|
}
|
|
write_unlock(&p->lock);
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
static int __initdata numabalancing_override;
|
|
|
|
static void __init check_numabalancing_enable(void)
|
|
{
|
|
bool numabalancing_default = false;
|
|
|
|
if (IS_ENABLED(CONFIG_NUMA_BALANCING_DEFAULT_ENABLED))
|
|
numabalancing_default = true;
|
|
|
|
/* Parsed by setup_numabalancing. override == 1 enables, -1 disables */
|
|
if (numabalancing_override)
|
|
set_numabalancing_state(numabalancing_override == 1);
|
|
|
|
if (num_online_nodes() > 1 && !numabalancing_override) {
|
|
pr_info("%s automatic NUMA balancing. Configure with numa_balancing= or the kernel.numa_balancing sysctl\n",
|
|
numabalancing_default ? "Enabling" : "Disabling");
|
|
set_numabalancing_state(numabalancing_default);
|
|
}
|
|
}
|
|
|
|
static int __init setup_numabalancing(char *str)
|
|
{
|
|
int ret = 0;
|
|
if (!str)
|
|
goto out;
|
|
|
|
if (!strcmp(str, "enable")) {
|
|
numabalancing_override = 1;
|
|
ret = 1;
|
|
} else if (!strcmp(str, "disable")) {
|
|
numabalancing_override = -1;
|
|
ret = 1;
|
|
}
|
|
out:
|
|
if (!ret)
|
|
pr_warn("Unable to parse numa_balancing=\n");
|
|
|
|
return ret;
|
|
}
|
|
__setup("numa_balancing=", setup_numabalancing);
|
|
#else
|
|
static inline void __init check_numabalancing_enable(void)
|
|
{
|
|
}
|
|
#endif /* CONFIG_NUMA_BALANCING */
|
|
|
|
/* assumes fs == KERNEL_DS */
|
|
void __init numa_policy_init(void)
|
|
{
|
|
nodemask_t interleave_nodes;
|
|
unsigned long largest = 0;
|
|
int nid, prefer = 0;
|
|
|
|
policy_cache = kmem_cache_create("numa_policy",
|
|
sizeof(struct mempolicy),
|
|
0, SLAB_PANIC, NULL);
|
|
|
|
sn_cache = kmem_cache_create("shared_policy_node",
|
|
sizeof(struct sp_node),
|
|
0, SLAB_PANIC, NULL);
|
|
|
|
for_each_node(nid) {
|
|
preferred_node_policy[nid] = (struct mempolicy) {
|
|
.refcnt = ATOMIC_INIT(1),
|
|
.mode = MPOL_PREFERRED,
|
|
.flags = MPOL_F_MOF | MPOL_F_MORON,
|
|
.nodes = nodemask_of_node(nid),
|
|
};
|
|
}
|
|
|
|
/*
|
|
* Set interleaving policy for system init. Interleaving is only
|
|
* enabled across suitably sized nodes (default is >= 16MB), or
|
|
* fall back to the largest node if they're all smaller.
|
|
*/
|
|
nodes_clear(interleave_nodes);
|
|
for_each_node_state(nid, N_MEMORY) {
|
|
unsigned long total_pages = node_present_pages(nid);
|
|
|
|
/* Preserve the largest node */
|
|
if (largest < total_pages) {
|
|
largest = total_pages;
|
|
prefer = nid;
|
|
}
|
|
|
|
/* Interleave this node? */
|
|
if ((total_pages << PAGE_SHIFT) >= (16 << 20))
|
|
node_set(nid, interleave_nodes);
|
|
}
|
|
|
|
/* All too small, use the largest */
|
|
if (unlikely(nodes_empty(interleave_nodes)))
|
|
node_set(prefer, interleave_nodes);
|
|
|
|
if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes))
|
|
pr_err("%s: interleaving failed\n", __func__);
|
|
|
|
check_numabalancing_enable();
|
|
}
|
|
|
|
/* Reset policy of current process to default */
|
|
void numa_default_policy(void)
|
|
{
|
|
do_set_mempolicy(MPOL_DEFAULT, 0, NULL);
|
|
}
|
|
|
|
/*
|
|
* Parse and format mempolicy from/to strings
|
|
*/
|
|
|
|
static const char * const policy_modes[] =
|
|
{
|
|
[MPOL_DEFAULT] = "default",
|
|
[MPOL_PREFERRED] = "prefer",
|
|
[MPOL_BIND] = "bind",
|
|
[MPOL_INTERLEAVE] = "interleave",
|
|
[MPOL_LOCAL] = "local",
|
|
[MPOL_PREFERRED_MANY] = "prefer (many)",
|
|
};
|
|
|
|
|
|
#ifdef CONFIG_TMPFS
|
|
/**
|
|
* mpol_parse_str - parse string to mempolicy, for tmpfs mpol mount option.
|
|
* @str: string containing mempolicy to parse
|
|
* @mpol: pointer to struct mempolicy pointer, returned on success.
|
|
*
|
|
* Format of input:
|
|
* <mode>[=<flags>][:<nodelist>]
|
|
*
|
|
* Return: %0 on success, else %1
|
|
*/
|
|
int mpol_parse_str(char *str, struct mempolicy **mpol)
|
|
{
|
|
struct mempolicy *new = NULL;
|
|
unsigned short mode_flags;
|
|
nodemask_t nodes;
|
|
char *nodelist = strchr(str, ':');
|
|
char *flags = strchr(str, '=');
|
|
int err = 1, mode;
|
|
|
|
if (flags)
|
|
*flags++ = '\0'; /* terminate mode string */
|
|
|
|
if (nodelist) {
|
|
/* NUL-terminate mode or flags string */
|
|
*nodelist++ = '\0';
|
|
if (nodelist_parse(nodelist, nodes))
|
|
goto out;
|
|
if (!nodes_subset(nodes, node_states[N_MEMORY]))
|
|
goto out;
|
|
} else
|
|
nodes_clear(nodes);
|
|
|
|
mode = match_string(policy_modes, MPOL_MAX, str);
|
|
if (mode < 0)
|
|
goto out;
|
|
|
|
switch (mode) {
|
|
case MPOL_PREFERRED:
|
|
/*
|
|
* Insist on a nodelist of one node only, although later
|
|
* we use first_node(nodes) to grab a single node, so here
|
|
* nodelist (or nodes) cannot be empty.
|
|
*/
|
|
if (nodelist) {
|
|
char *rest = nodelist;
|
|
while (isdigit(*rest))
|
|
rest++;
|
|
if (*rest)
|
|
goto out;
|
|
if (nodes_empty(nodes))
|
|
goto out;
|
|
}
|
|
break;
|
|
case MPOL_INTERLEAVE:
|
|
/*
|
|
* Default to online nodes with memory if no nodelist
|
|
*/
|
|
if (!nodelist)
|
|
nodes = node_states[N_MEMORY];
|
|
break;
|
|
case MPOL_LOCAL:
|
|
/*
|
|
* Don't allow a nodelist; mpol_new() checks flags
|
|
*/
|
|
if (nodelist)
|
|
goto out;
|
|
break;
|
|
case MPOL_DEFAULT:
|
|
/*
|
|
* Insist on a empty nodelist
|
|
*/
|
|
if (!nodelist)
|
|
err = 0;
|
|
goto out;
|
|
case MPOL_PREFERRED_MANY:
|
|
case MPOL_BIND:
|
|
/*
|
|
* Insist on a nodelist
|
|
*/
|
|
if (!nodelist)
|
|
goto out;
|
|
}
|
|
|
|
mode_flags = 0;
|
|
if (flags) {
|
|
/*
|
|
* Currently, we only support two mutually exclusive
|
|
* mode flags.
|
|
*/
|
|
if (!strcmp(flags, "static"))
|
|
mode_flags |= MPOL_F_STATIC_NODES;
|
|
else if (!strcmp(flags, "relative"))
|
|
mode_flags |= MPOL_F_RELATIVE_NODES;
|
|
else
|
|
goto out;
|
|
}
|
|
|
|
new = mpol_new(mode, mode_flags, &nodes);
|
|
if (IS_ERR(new))
|
|
goto out;
|
|
|
|
/*
|
|
* Save nodes for mpol_to_str() to show the tmpfs mount options
|
|
* for /proc/mounts, /proc/pid/mounts and /proc/pid/mountinfo.
|
|
*/
|
|
if (mode != MPOL_PREFERRED) {
|
|
new->nodes = nodes;
|
|
} else if (nodelist) {
|
|
nodes_clear(new->nodes);
|
|
node_set(first_node(nodes), new->nodes);
|
|
} else {
|
|
new->mode = MPOL_LOCAL;
|
|
}
|
|
|
|
/*
|
|
* Save nodes for contextualization: this will be used to "clone"
|
|
* the mempolicy in a specific context [cpuset] at a later time.
|
|
*/
|
|
new->w.user_nodemask = nodes;
|
|
|
|
err = 0;
|
|
|
|
out:
|
|
/* Restore string for error message */
|
|
if (nodelist)
|
|
*--nodelist = ':';
|
|
if (flags)
|
|
*--flags = '=';
|
|
if (!err)
|
|
*mpol = new;
|
|
return err;
|
|
}
|
|
#endif /* CONFIG_TMPFS */
|
|
|
|
/**
|
|
* mpol_to_str - format a mempolicy structure for printing
|
|
* @buffer: to contain formatted mempolicy string
|
|
* @maxlen: length of @buffer
|
|
* @pol: pointer to mempolicy to be formatted
|
|
*
|
|
* Convert @pol into a string. If @buffer is too short, truncate the string.
|
|
* Recommend a @maxlen of at least 51 for the longest mode, "weighted
|
|
* interleave", plus the longest flag flags, "relative|balancing", and to
|
|
* display at least a few node ids.
|
|
*/
|
|
void mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
|
|
{
|
|
char *p = buffer;
|
|
nodemask_t nodes = NODE_MASK_NONE;
|
|
unsigned short mode = MPOL_DEFAULT;
|
|
unsigned short flags = 0;
|
|
|
|
if (pol &&
|
|
pol != &default_policy &&
|
|
!(pol >= &preferred_node_policy[0] &&
|
|
pol <= &preferred_node_policy[ARRAY_SIZE(preferred_node_policy) - 1])) {
|
|
mode = pol->mode;
|
|
flags = pol->flags;
|
|
}
|
|
|
|
switch (mode) {
|
|
case MPOL_DEFAULT:
|
|
case MPOL_LOCAL:
|
|
break;
|
|
case MPOL_PREFERRED:
|
|
case MPOL_PREFERRED_MANY:
|
|
case MPOL_BIND:
|
|
case MPOL_INTERLEAVE:
|
|
nodes = pol->nodes;
|
|
break;
|
|
default:
|
|
WARN_ON_ONCE(1);
|
|
snprintf(p, maxlen, "unknown");
|
|
return;
|
|
}
|
|
|
|
p += snprintf(p, maxlen, "%s", policy_modes[mode]);
|
|
|
|
if (flags & MPOL_MODE_FLAGS) {
|
|
p += snprintf(p, buffer + maxlen - p, "=");
|
|
|
|
/*
|
|
* Static and relative are mutually exclusive.
|
|
*/
|
|
if (flags & MPOL_F_STATIC_NODES)
|
|
p += snprintf(p, buffer + maxlen - p, "static");
|
|
else if (flags & MPOL_F_RELATIVE_NODES)
|
|
p += snprintf(p, buffer + maxlen - p, "relative");
|
|
|
|
if (flags & MPOL_F_NUMA_BALANCING) {
|
|
if (!is_power_of_2(flags & MPOL_MODE_FLAGS))
|
|
p += snprintf(p, buffer + maxlen - p, "|");
|
|
p += snprintf(p, buffer + maxlen - p, "balancing");
|
|
}
|
|
}
|
|
|
|
if (!nodes_empty(nodes))
|
|
p += scnprintf(p, buffer + maxlen - p, ":%*pbl",
|
|
nodemask_pr_args(&nodes));
|
|
}
|