OpenCloudOS-Kernel/include
Daniel Vetter 95d6c701f4 mm: extract might_alloc() debug check
Extracted from slab.h, which seems to have the most complete version
including the correct might_sleep() check.  Roll it out to slob.c.

Motivated by a discussion with Paul about possibly changing call_rcu
behaviour to allocate memory, but only roughly every 500th call.

There are a lot fewer places in the kernel that care about whether
allocating memory is allowed or not (due to deadlocks with reclaim code)
than places that care whether sleeping is allowed.  But debugging these
also tends to be a lot harder, so nice descriptive checks could come in
handy.  I might have some use eventually for annotations in drivers/gpu.

Note that unlike fs_reclaim_acquire/release gfpflags_allow_blocking does
not consult the PF_MEMALLOC flags.  But there is no flag equivalent for
GFP_NOWAIT, hence this check can't go wrong due to
memalloc_no*_save/restore contexts.  Willy is working on a patch series
which might change this:

https://lore.kernel.org/linux-mm/20200625113122.7540-7-willy@infradead.org/

I think best would be if that updates gfpflags_allow_blocking(), since
there's a ton of callers all over the place for that already.

Link: https://lkml.kernel.org/r/20201125162532.1299794-3-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Waiman Long <longman@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Qian Cai <cai@lca.pw>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Thomas Hellström (Intel) <thomas_os@shipmail.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:41 -08:00
..
acpi pci-v5.10-changes 2020-10-22 12:41:00 -07:00
asm-generic Merge branch 'for-5.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu 2020-11-15 08:57:19 -08:00
clocksource
crypto
drm drm: drm_print.h: fix kernel-doc markups 2020-10-27 11:21:39 +01:00
dt-bindings ARM: Devicetree updates 2020-10-24 10:44:18 -07:00
keys
kunit kunit: fix display of failed expectations for strings 2020-11-10 13:45:15 -07:00
kvm ARM: 2020-10-23 11:17:56 -07:00
linux mm: extract might_alloc() debug check 2020-12-15 12:13:41 -08:00
math-emu
media ARM: SoC platform updates 2020-10-24 10:33:08 -07:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2020-12-10 14:29:30 -08:00
pcmcia
ras mm,hwpoison: introduce MF_MSG_UNSPLIT_THP 2020-10-16 11:11:17 -07:00
rdma RDMA: Add rdma_connect_locked() 2020-10-28 09:14:49 -03:00
scsi scsi: libiscsi: Fix NOP race condition 2020-11-16 22:32:50 -05:00
soc net: mscc: ocelot: fix dropping of unknown IPv4 multicast on Seville 2020-12-05 15:41:34 -08:00
sound ASoC: Fixes for v5.11 2020-11-19 19:56:29 +01:00
target
trace mm: mmap_lock: add tracepoints around lock acquisition 2020-12-15 12:13:41 -08:00
uapi uapi: move constants from <linux/kernel.h> to <linux/const.h> 2020-12-15 12:13:36 -08:00
vdso
video gpu: ipu-v3: remove unused functions 2020-10-26 10:42:38 +01:00
xen xen: don't use page->lru for ZONE_DEVICE memory 2020-12-09 10:31:41 +01:00