linux/include
Will Deacon 721c21c17a mm: mmu_gather: use tlb->end != 0 only for TLB invalidation
When batching up address ranges for TLB invalidation, we check tlb->end
!= 0 to indicate that some pages have actually been unmapped.

As of commit f045bbb9fa ("mmu_gather: fix over-eager
tlb_flush_mmu_free() calling"), we use the same check for freeing these
pages in order to avoid a performance regression where we call
free_pages_and_swap_cache even when no pages are actually queued up.

Unfortunately, the range could have been reset (tlb->end = 0) by
tlb_end_vma, which has been shown to cause memory leaks on arm64.
Furthermore, investigation into these leaks revealed that the fullmm
case on task exit no longer invalidates the TLB, by virtue of tlb->end
 == 0 (in 3.18, need_flush would have been set).

This patch resolves the problem by reverting commit f045bbb9fa, using
instead tlb->local.nr as the predicate for page freeing in
tlb_flush_mmu_free and ensuring that tlb->end is initialised to a
non-zero value in the fullmm case.

Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Dave Hansen <dave@sr71.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-13 15:20:40 +13:00
..
acpi ACPI / processor: Convert apic_id to phys_id to make it arch agnostic 2015-01-05 23:32:42 +01:00
asm-generic mm: mmu_gather: use tlb->end != 0 only for TLB invalidation 2015-01-13 15:20:40 +13:00
clocksource
crypto crypto: af_alg - add user space interface for AEAD 2014-12-05 23:56:55 +08:00
drm Revert "drm/gem: Warn on illegal use of the dumb buffer interface v2" 2014-12-24 13:13:22 +10:00
dt-bindings Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal into thermal-soc 2014-12-21 22:49:12 +08:00
keys
kvm arm/arm64: KVM: Require in-kernel vgic for the arch timers 2014-12-15 11:50:42 +01:00
linux Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-01-11 11:47:45 -08:00
math-emu
media [media] media: v4l2-image-sizes.h: correct the SVGA height definition 2014-12-04 13:56:56 -02:00
memory
misc
net Here's just a single fix - a revert of a patch that broke the 2015-01-06 13:29:27 -05:00
pcmcia
ras
rdma IB/core: Implement support for MMU notifiers regarding on demand paging regions 2014-12-15 18:13:36 -08:00
rxrpc
scsi SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
soc Merge branch 'at91/cleanup5' into next/drivers 2014-12-08 18:29:20 +01:00
sound ALSA: pcm: Fix kerneldoc for params_*() functions 2014-12-30 16:41:11 +01:00
target SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
trace SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
uapi Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2015-01-09 21:13:34 -08:00
video OMAPDSS: Remove all references to obsolete HDMI audio callbacks 2014-12-01 11:09:59 +02:00
xen xen/arm: introduce GNTTABOP_cache_flush 2014-12-04 12:41:54 +00:00
Kbuild