drm/amdgpu: Use mmu_interval_notifier instead of hmm_mirror

Convert the collision-retry lock around hmm_range_fault to use the one now
provided by the mmu_interval notifier.

Although this driver does not seem to use the collision retry lock that
hmm provides correctly, it can still be converted over to use the
mmu_interval_notifier api instead of hmm_mirror without too much trouble.

This also deletes another place where a driver is associating additional
data (struct amdgpu_mn) with a mmu_struct.

Link: https://lore.kernel.org/r/20191112202231.3856-13-jgg@ziepe.ca
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Philip Yang <Philip.Yang@amd.com>
Tested-by: Philip Yang <Philip.Yang@amd.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit is contained in:
Jason Gunthorpe 2019-11-12 16:22:29 -04:00
parent 62914a99de
commit 81fa1af31b
5 changed files with 94 additions and 237 deletions

View File

@ -1738,6 +1738,10 @@ static int update_invalid_user_pages(struct amdkfd_process_info *process_info,
return ret;
}
/*
* FIXME: Cannot ignore the return code, must hold
* notifier_lock
*/
amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
/* Mark the BO as valid unless it was invalidated

View File

@ -603,8 +603,6 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
e->tv.num_shared = 2;
amdgpu_bo_list_get_list(p->bo_list, &p->validated);
if (p->bo_list->first_userptr != p->bo_list->num_entries)
p->mn = amdgpu_mn_get(p->adev, AMDGPU_MN_TYPE_GFX);
INIT_LIST_HEAD(&duplicates);
amdgpu_vm_get_pd_bo(&fpriv->vm, &p->validated, &p->vm_pd);
@ -1287,11 +1285,11 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
if (r)
goto error_unlock;
/* No memory allocation is allowed while holding the mn lock.
* p->mn is hold until amdgpu_cs_submit is finished and fence is added
* to BOs.
/* No memory allocation is allowed while holding the notifier lock.
* The lock is held until amdgpu_cs_submit is finished and fence is
* added to BOs.
*/
amdgpu_mn_lock(p->mn);
mutex_lock(&p->adev->notifier_lock);
/* If userptr are invalidated after amdgpu_cs_parser_bos(), return
* -EAGAIN, drmIoctl in libdrm will restart the amdgpu_cs_ioctl.
@ -1334,13 +1332,13 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
amdgpu_vm_move_to_lru_tail(p->adev, &fpriv->vm);
ttm_eu_fence_buffer_objects(&p->ticket, &p->validated, p->fence);
amdgpu_mn_unlock(p->mn);
mutex_unlock(&p->adev->notifier_lock);
return 0;
error_abort:
drm_sched_job_cleanup(&job->base);
amdgpu_mn_unlock(p->mn);
mutex_unlock(&p->adev->notifier_lock);
error_unlock:
amdgpu_job_free(job);

View File

@ -50,28 +50,6 @@
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
/**
* amdgpu_mn_lock - take the write side lock for this notifier
*
* @mn: our notifier
*/
void amdgpu_mn_lock(struct amdgpu_mn *mn)
{
if (mn)
down_write(&mn->lock);
}
/**
* amdgpu_mn_unlock - drop the write side lock for this notifier
*
* @mn: our notifier
*/
void amdgpu_mn_unlock(struct amdgpu_mn *mn)
{
if (mn)
up_write(&mn->lock);
}
/**
* amdgpu_mn_invalidate_gfx - callback to notify about mm change
*
@ -94,6 +72,9 @@ static bool amdgpu_mn_invalidate_gfx(struct mmu_interval_notifier *mni,
return false;
mutex_lock(&adev->notifier_lock);
mmu_interval_set_seq(mni, cur_seq);
r = dma_resv_wait_timeout_rcu(bo->tbo.base.resv, true, false,
MAX_SCHEDULE_TIMEOUT);
mutex_unlock(&adev->notifier_lock);
@ -127,6 +108,9 @@ static bool amdgpu_mn_invalidate_hsa(struct mmu_interval_notifier *mni,
return false;
mutex_lock(&adev->notifier_lock);
mmu_interval_set_seq(mni, cur_seq);
amdgpu_amdkfd_evict_userptr(bo->kfd_bo, bo->notifier.mm);
mutex_unlock(&adev->notifier_lock);
@ -137,92 +121,6 @@ static const struct mmu_interval_notifier_ops amdgpu_mn_hsa_ops = {
.invalidate = amdgpu_mn_invalidate_hsa,
};
static int amdgpu_mn_sync_pagetables(struct hmm_mirror *mirror,
const struct mmu_notifier_range *update)
{
struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror);
if (!mmu_notifier_range_blockable(update))
return -EAGAIN;
down_read(&amn->lock);
up_read(&amn->lock);
return 0;
}
/* Low bits of any reasonable mm pointer will be unused due to struct
* alignment. Use these bits to make a unique key from the mm pointer
* and notifier type.
*/
#define AMDGPU_MN_KEY(mm, type) ((unsigned long)(mm) + (type))
static struct hmm_mirror_ops amdgpu_hmm_mirror_ops[] = {
[AMDGPU_MN_TYPE_GFX] = {
.sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables,
},
[AMDGPU_MN_TYPE_HSA] = {
.sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables,
},
};
/**
* amdgpu_mn_get - create HMM mirror context
*
* @adev: amdgpu device pointer
* @type: type of MMU notifier context
*
* Creates a HMM mirror context for current->mm.
*/
struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
enum amdgpu_mn_type type)
{
struct mm_struct *mm = current->mm;
struct amdgpu_mn *amn;
unsigned long key = AMDGPU_MN_KEY(mm, type);
int r;
mutex_lock(&adev->mn_lock);
if (down_write_killable(&mm->mmap_sem)) {
mutex_unlock(&adev->mn_lock);
return ERR_PTR(-EINTR);
}
hash_for_each_possible(adev->mn_hash, amn, node, key)
if (AMDGPU_MN_KEY(amn->mirror.hmm->mmu_notifier.mm,
amn->type) == key)
goto release_locks;
amn = kzalloc(sizeof(*amn), GFP_KERNEL);
if (!amn) {
amn = ERR_PTR(-ENOMEM);
goto release_locks;
}
amn->adev = adev;
init_rwsem(&amn->lock);
amn->type = type;
amn->mirror.ops = &amdgpu_hmm_mirror_ops[type];
r = hmm_mirror_register(&amn->mirror, mm);
if (r)
goto free_amn;
hash_add(adev->mn_hash, &amn->node, AMDGPU_MN_KEY(mm, type));
release_locks:
up_write(&mm->mmap_sem);
mutex_unlock(&adev->mn_lock);
return amn;
free_amn:
up_write(&mm->mmap_sem);
mutex_unlock(&adev->mn_lock);
kfree(amn);
return ERR_PTR(r);
}
/**
* amdgpu_mn_register - register a BO for notifier updates
*
@ -235,12 +133,12 @@ free_amn:
int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
{
if (bo->kfd_bo)
bo->notifier.ops = &amdgpu_mn_hsa_ops;
else
bo->notifier.ops = &amdgpu_mn_gfx_ops;
return mmu_interval_notifier_insert(&bo->notifier, addr,
amdgpu_bo_size(bo), current->mm);
return mmu_interval_notifier_insert(&bo->notifier, current->mm,
addr, amdgpu_bo_size(bo),
&amdgpu_mn_hsa_ops);
return mmu_interval_notifier_insert(&bo->notifier, current->mm, addr,
amdgpu_bo_size(bo),
&amdgpu_mn_gfx_ops);
}
/**
@ -257,25 +155,3 @@ void amdgpu_mn_unregister(struct amdgpu_bo *bo)
mmu_interval_notifier_remove(&bo->notifier);
bo->notifier.mm = NULL;
}
/* flags used by HMM internal, not related to CPU/GPU PTE flags */
static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = {
(1 << 0), /* HMM_PFN_VALID */
(1 << 1), /* HMM_PFN_WRITE */
0 /* HMM_PFN_DEVICE_PRIVATE */
};
static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = {
0xfffffffffffffffeUL, /* HMM_PFN_ERROR */
0, /* HMM_PFN_NONE */
0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */
};
void amdgpu_hmm_init_range(struct hmm_range *range)
{
if (range) {
range->flags = hmm_range_flags;
range->values = hmm_range_values;
range->pfn_shift = PAGE_SHIFT;
}
}

View File

@ -30,59 +30,10 @@
#include <linux/workqueue.h>
#include <linux/interval_tree.h>
enum amdgpu_mn_type {
AMDGPU_MN_TYPE_GFX,
AMDGPU_MN_TYPE_HSA,
};
/**
* struct amdgpu_mn
*
* @adev: amdgpu device pointer
* @type: type of MMU notifier
* @work: destruction work item
* @node: hash table node to find structure by adev and mn
* @lock: rw semaphore protecting the notifier nodes
* @mirror: HMM mirror function support
*
* Data for each amdgpu device and process address space.
*/
struct amdgpu_mn {
/* constant after initialisation */
struct amdgpu_device *adev;
enum amdgpu_mn_type type;
/* only used on destruction */
struct work_struct work;
/* protected by adev->mn_lock */
struct hlist_node node;
/* objects protected by lock */
struct rw_semaphore lock;
#ifdef CONFIG_HMM_MIRROR
/* HMM mirror */
struct hmm_mirror mirror;
#endif
};
#if defined(CONFIG_HMM_MIRROR)
void amdgpu_mn_lock(struct amdgpu_mn *mn);
void amdgpu_mn_unlock(struct amdgpu_mn *mn);
struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
enum amdgpu_mn_type type);
int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr);
void amdgpu_mn_unregister(struct amdgpu_bo *bo);
void amdgpu_hmm_init_range(struct hmm_range *range);
#else
static inline void amdgpu_mn_lock(struct amdgpu_mn *mn) {}
static inline void amdgpu_mn_unlock(struct amdgpu_mn *mn) {}
static inline struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
enum amdgpu_mn_type type)
{
return NULL;
}
static inline int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
{
DRM_WARN_ONCE("HMM_MIRROR kernel config option is not enabled, "

View File

@ -773,6 +773,20 @@ struct amdgpu_ttm_tt {
#endif
};
#ifdef CONFIG_DRM_AMDGPU_USERPTR
/* flags used by HMM internal, not related to CPU/GPU PTE flags */
static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = {
(1 << 0), /* HMM_PFN_VALID */
(1 << 1), /* HMM_PFN_WRITE */
0 /* HMM_PFN_DEVICE_PRIVATE */
};
static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = {
0xfffffffffffffffeUL, /* HMM_PFN_ERROR */
0, /* HMM_PFN_NONE */
0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */
};
/**
* amdgpu_ttm_tt_get_user_pages - get device accessible pages that back user
* memory and start HMM tracking CPU page table update
@ -780,29 +794,28 @@ struct amdgpu_ttm_tt {
* Calling function must call amdgpu_ttm_tt_userptr_range_done() once and only
* once afterwards to stop HMM tracking
*/
#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR)
#define MAX_RETRY_HMM_RANGE_FAULT 16
int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages)
{
struct hmm_mirror *mirror = bo->mn ? &bo->mn->mirror : NULL;
struct ttm_tt *ttm = bo->tbo.ttm;
struct amdgpu_ttm_tt *gtt = (void *)ttm;
struct mm_struct *mm;
unsigned long start = gtt->userptr;
struct vm_area_struct *vma;
struct hmm_range *range;
unsigned long timeout;
struct mm_struct *mm;
unsigned long i;
uint64_t *pfns;
int r = 0;
if (unlikely(!mirror)) {
DRM_DEBUG_DRIVER("Failed to get hmm_mirror\n");
mm = bo->notifier.mm;
if (unlikely(!mm)) {
DRM_DEBUG_DRIVER("BO is not registered?\n");
return -EFAULT;
}
mm = mirror->hmm->mmu_notifier.mm;
/* Another get_user_pages is running at the same time?? */
if (WARN_ON(gtt->range))
return -EFAULT;
if (!mmget_not_zero(mm)) /* Happens during process shutdown */
return -ESRCH;
@ -811,31 +824,23 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages)
r = -ENOMEM;
goto out;
}
range->notifier = &bo->notifier;
range->flags = hmm_range_flags;
range->values = hmm_range_values;
range->pfn_shift = PAGE_SHIFT;
range->start = bo->notifier.interval_tree.start;
range->end = bo->notifier.interval_tree.last + 1;
range->default_flags = hmm_range_flags[HMM_PFN_VALID];
if (!amdgpu_ttm_tt_is_readonly(ttm))
range->default_flags |= range->flags[HMM_PFN_WRITE];
pfns = kvmalloc_array(ttm->num_pages, sizeof(*pfns), GFP_KERNEL);
if (unlikely(!pfns)) {
range->pfns = kvmalloc_array(ttm->num_pages, sizeof(*range->pfns),
GFP_KERNEL);
if (unlikely(!range->pfns)) {
r = -ENOMEM;
goto out_free_ranges;
}
amdgpu_hmm_init_range(range);
range->default_flags = range->flags[HMM_PFN_VALID];
range->default_flags |= amdgpu_ttm_tt_is_readonly(ttm) ?
0 : range->flags[HMM_PFN_WRITE];
range->pfn_flags_mask = 0;
range->pfns = pfns;
range->start = start;
range->end = start + ttm->num_pages * PAGE_SIZE;
hmm_range_register(range, mirror);
/*
* Just wait for range to be valid, safe to ignore return value as we
* will use the return value of hmm_range_fault() below under the
* mmap_sem to ascertain the validity of the range.
*/
hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT);
down_read(&mm->mmap_sem);
vma = find_vma(mm, start);
if (unlikely(!vma || start < vma->vm_start)) {
@ -847,18 +852,31 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages)
r = -EPERM;
goto out_unlock;
}
up_read(&mm->mmap_sem);
timeout = jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);
retry:
range->notifier_seq = mmu_interval_read_begin(&bo->notifier);
down_read(&mm->mmap_sem);
r = hmm_range_fault(range, 0);
up_read(&mm->mmap_sem);
if (unlikely(r < 0))
if (unlikely(r <= 0)) {
/*
* FIXME: This timeout should encompass the retry from
* mmu_interval_read_retry() as well.
*/
if ((r == 0 || r == -EBUSY) && !time_after(jiffies, timeout))
goto retry;
goto out_free_pfns;
}
for (i = 0; i < ttm->num_pages; i++) {
pages[i] = hmm_device_entry_to_page(range, pfns[i]);
/* FIXME: The pages cannot be touched outside the notifier_lock */
pages[i] = hmm_device_entry_to_page(range, range->pfns[i]);
if (unlikely(!pages[i])) {
pr_err("Page fault failed for pfn[%lu] = 0x%llx\n",
i, pfns[i]);
i, range->pfns[i]);
r = -ENOMEM;
goto out_free_pfns;
@ -873,8 +891,7 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages)
out_unlock:
up_read(&mm->mmap_sem);
out_free_pfns:
hmm_range_unregister(range);
kvfree(pfns);
kvfree(range->pfns);
out_free_ranges:
kfree(range);
out:
@ -903,15 +920,18 @@ bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm)
"No user pages to check\n");
if (gtt->range) {
r = hmm_range_valid(gtt->range);
hmm_range_unregister(gtt->range);
/*
* FIXME: Must always hold notifier_lock for this, and must
* not ignore the return code.
*/
r = mmu_interval_read_retry(gtt->range->notifier,
gtt->range->notifier_seq);
kvfree(gtt->range->pfns);
kfree(gtt->range);
gtt->range = NULL;
}
return r;
return !r;
}
#endif
@ -992,10 +1012,18 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
sg_free_table(ttm->sg);
#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR)
if (gtt->range &&
ttm->pages[0] == hmm_device_entry_to_page(gtt->range,
gtt->range->pfns[0]))
WARN_ONCE(1, "Missing get_user_page_done\n");
if (gtt->range) {
unsigned long i;
for (i = 0; i < ttm->num_pages; i++) {
if (ttm->pages[i] !=
hmm_device_entry_to_page(gtt->range,
gtt->range->pfns[i]))
break;
}
WARN((i == ttm->num_pages), "Missing get_user_page_done\n");
}
#endif
}