linux-sg2042/drivers/misc/sgi-gru
Jason Gunthorpe e4c057d02c misc/sgi-gru: use mmu_notifier_get/put for struct gru_mm_struct
GRU is already using almost the same algorithm as get/put, it even
helpfully has a 10 year old comment to make this algorithm common, which
is finally happening.

There are a few differences and fixes from this conversion:
- GRU used rcu not srcu to read the hlist
- Unclear how the locking worked to prevent gru_register_mmu_notifier()
  from running concurrently with gru_drop_mmu_notifier() - this version is
  safe
- GRU had a release function which only set a variable without any locking
  that skiped the synchronize_srcu during unregister which looks racey,
  but this makes it reliable via the integrated call_srcu().
- It is unclear if the mmap_sem is actually held when
  __mmu_notifier_register() was called, lockdep will now warn if this is
  wrong

Link: https://lore.kernel.org/r/20190806231548.25242-5-jgg@ziepe.ca
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dimitri Sivanich <sivanich@hpe.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-16 12:02:59 -03:00
..
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
gru.h gru: improve GRU TLB dropin statistics 2009-12-16 07:20:17 -08:00
gru_instructions.h Add #includes needed to permit the removal of asm/system.h 2012-03-28 18:30:03 +01:00
grufault.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
grufile.c misc/sgi-gru: use mmu_notifier_get/put for struct gru_mm_struct 2019-08-16 12:02:59 -03:00
gruhandles.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
gruhandles.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
grukdump.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
grukservices.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
grukservices.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
grulib.h gru: improve GRU TLB dropin statistics 2009-12-16 07:20:17 -08:00
grumain.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
gruprocfs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
grutables.h misc/sgi-gru: use mmu_notifier_get/put for struct gru_mm_struct 2019-08-16 12:02:59 -03:00
grutlbpurge.c misc/sgi-gru: use mmu_notifier_get/put for struct gru_mm_struct 2019-08-16 12:02:59 -03:00