linux-stable.git/kernel/power/snapshot.c, branch v4.19.78

PM: hibernate: Do not subtract NR_FILE_MAPPED in minimum_image_size()

2018-01-05T13:46:25+00:00

s2disk/s2both may fail unnecessarily and erratically if NR_FILE_MAPPED
is high - for instance when using VMs with VirtualBox and perhaps VMware
Player. In those situations s2disk becomes unreliable and therefore
unusable.

A typical scenario is: user issues a s2disk and it fails. User issues
a second s2disk immediately after that and it succeeds.  And user
wonders why.

The problem is caused by minimum_image_size() in snapshot.c.  The
value it returns is roughly 100% too high because NR_FILE_MAPPED is
subtracted in its calculation.  Eventually the number of preallocated
image pages is falsely too low.

This doesn't matter as long as NR_FILE_MAPPED-values are in a normal
range or in 32bit-environments as the code allows for allocation of
additional pages from highmem.

But with the high values generated by VirtualBox-VMs (a 2-GB-VM causes
NR_FILE_MAPPED go up by 2 GB) it may lead to failure in 64bit-systems.

Not subtracting NR_FILE_MAPPED in minimum_image_size() solves the
problem.

I've done at least hundreds of successful s2both/s2disk now on an
x86_64 system (with and without VirtualBox) which gives me some
confidence that this is right.  It has turned s2disk/s2both from
unusable into 100% reliable.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=97201
Signed-off-by: Rainer Fiebig 
Signed-off-by: Rafael J. Wysocki

mm: remove __GFP_COLD

2017-11-16T02:21:06+00:00

As the page free path makes no distinction between cache hot and cold
pages, there is no real useful ordering of pages in the free list that
allocation requests can take advantage of.  Juding from the users of
__GFP_COLD, it is likely that a number of them are the result of copying
other sites instead of actually measuring the impact.  Remove the
__GFP_COLD parameter which simplifies a number of paths in the page
allocator.

This is potentially controversial but bear in mind that the size of the
per-cpu pagelists versus modern cache sizes means that the whole per-cpu
list can often fit in the L3 cache.  Hence, there is only a potential
benefit for microbenchmarks that alloc/free pages in a tight loop.  It's
even worse when THP is taken into account which has little or no chance
of getting a cache-hot page as the per-cpu list is bypassed and the
zeroing of multiple pages will thrash the cache anyway.

The truncate microbenchmarks are not shown as this patch affects the
allocation path and not the free path.  A page fault microbenchmark was
tested but it showed no sigificant difference which is not surprising
given that the __GFP_COLD branches are a miniscule percentage of the
fault path.

Link: http://lkml.kernel.org/r/20171018075952.10627-9-mgorman@techsingularity.net
Signed-off-by: Mel Gorman 
Acked-by: Vlastimil Babka 
Cc: Andi Kleen 
Cc: Dave Chinner 
Cc: Dave Hansen 
Cc: Jan Kara 
Cc: Johannes Weiner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

PM: Use a more common logging style

2017-10-03T00:57:17+00:00

Convert printks to pr_.

Miscellanea:

o Use pr_fmt with "PM:" and remove "PM: " from format strings
o Coalesce format strings and realign format arguments
o Convert an embedded incorrect function name to "%s: ", __func__
o Convert a couple multi-line formats to multiple pr_ calls

Signed-off-by: Joe Perches 
Acked-by: Pavel Machek 
Signed-off-by: Rafael J. Wysocki

mm: fix global NR_SLAB_.*CLAIMABLE counter reads

2017-08-10T22:54:06+00:00

As Tetsuo points out:
 "Commit 385386cff4c6 ("mm: vmstat: move slab statistics from zone to
  node counters") broke "Slab:" field of /proc/meminfo . It shows nearly
  0kB"

In addition to /proc/meminfo, this problem also affects the slab
counters OOM/allocation failure info dumps, can cause early -ENOMEM from
overcommit protection, and miscalculate image size requirements during
suspend-to-disk.

This is because the patch in question switched the slab counters from
the zone level to the node level, but forgot to update the global
accessor functions to read the aggregate node data instead of the
aggregate zone data.

Use global_node_page_state() to access the global slab counters.

Fixes: 385386cff4c6 ("mm: vmstat: move slab statistics from zone to node counters")
Link: http://lkml.kernel.org/r/20170801134256.5400-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner 
Reported-by: Tetsuo Handa 
Acked-by: Michal Hocko 
Cc: Josef Bacik 
Cc: Vladimir Davydov 
Cc: Stefan Agner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kernel/power/snapshot.c: use linux/set_memory.h

2017-07-06T23:24:30+00:00

This header always exists, so doesn't require an ifdef around its
inclusion.  When CONFIG_ARCH_HAS_SET_MEMORY=y it includes the asm
header, otherwise it provides empty versions of the set_memory_xx()
routines.

Link: http://lkml.kernel.org/r/1498717781-29151-2-git-send-email-mpe@ellerman.id.au
Signed-off-by: Michael Ellerman 
Acked-by: Kees Cook 
Acked-by: Laura Abbott 
Cc: Daniel Borkmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

PM / hibernate: Drop redundant parameter of swsusp_alloc()

2017-06-27T00:10:44+00:00

The first parameter of swsusp_alloc is not used, so drop it.

Signed-off-by: BaoJun Luo 
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki

PM / hibernate: Use CONFIG_HAVE_SET_MEMORY for include condition

2017-06-27T00:05:28+00:00

Kbuild reported a build failure when CONFIG_STRICT_KERNEL_RWX was
enabled on powerpc. We don't yet have ARCH_HAS_SET_MEMORY and ppc32
saw a build failure.

I've only done a basic compile test with a config that has
hibernation enabled.

Fixes: 50327ddfbc92 (kernel/power/snapshot.c: use set_memory.h header)
Reported-by: Christophe Leroy 
Signed-off-by: Balbir Singh 
Acked-by: Pavel Machek 
Signed-off-by: Rafael J. Wysocki

Merge branches 'pm-sleep' and 'powercap'

2017-05-22T18:32:05+00:00

* pm-sleep:
  PM / hibernate: Declare variables as static
  RTC: rtc-cmos: Fix wakeup from suspend-to-idle
  PM / wakeup: Fix up wakeup_source_report_event()

* powercap:
  PowerCap: Fix an error code in powercap_register_zone()

PM / hibernate: Declare variables as static

2017-05-14T11:33:24+00:00

Fixing sparse warnings: 'symbol not declared. Should it be static?'

Signed-off-by: Pushkar Jambhlekar 
Signed-off-by: Rafael J. Wysocki

kernel/power/snapshot.c: use set_memory.h header

2017-05-09T00:15:14+00:00

set_memory_* functions have moved to set_memory.h.  Switch to this
explicitly.

Link: http://lkml.kernel.org/r/1488920133-27229-13-git-send-email-labbott@redhat.com
Signed-off-by: Laura Abbott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds