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  1. 13 11月, 2013 8 次提交
    • J
      mm: factor commit limit calculation · 00619bcc
      由 Jerome Marchand 提交于 
      The same calculation is currently done in three differents places.
Factor that code so future changes has to be made at only one place.

[akpm@linux-foundation.org: uninline vm_commit_limit()]
Signed-off-by: NJerome Marchand <jmarchan@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      00619bcc
    • T
      mm/memblock.c: introduce bottom-up allocation mode · 79442ed1
      由 Tang Chen 提交于 
      The Linux kernel cannot migrate pages used by the kernel.  As a result,
kernel pages cannot be hot-removed.  So we cannot allocate hotpluggable
memory for the kernel.

ACPI SRAT (System Resource Affinity Table) contains the memory hotplug
info.  But before SRAT is parsed, memblock has already started to allocate
memory for the kernel.  So we need to prevent memblock from doing this.

In a memory hotplug system, any numa node the kernel resides in should be
unhotpluggable.  And for a modern server, each node could have at least
16GB memory.  So memory around the kernel image is highly likely
unhotpluggable.

So the basic idea is: Allocate memory from the end of the kernel image and
to the higher memory.  Since memory allocation before SRAT is parsed won't
be too much, it could highly likely be in the same node with kernel image.

The current memblock can only allocate memory top-down.  So this patch
introduces a new bottom-up allocation mode to allocate memory bottom-up.
And later when we use this allocation direction to allocate memory, we
will limit the start address above the kernel.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      79442ed1
    • J
      writeback: do not sync data dirtied after sync start · c4a391b5
      由 Jan Kara 提交于 
      When there are processes heavily creating small files while sync(2) is
running, it can easily happen that quite some new files are created
between WB_SYNC_NONE and WB_SYNC_ALL pass of sync(2).  That can happen
especially if there are several busy filesystems (remember that sync
traverses filesystems sequentially and waits in WB_SYNC_ALL phase on one
fs before starting it on another fs).  Because WB_SYNC_ALL pass is slow
(e.g.  causes a transaction commit and cache flush for each inode in
ext3), resulting sync(2) times are rather large.

The following script reproduces the problem:

  function run_writers
  {
    for (( i = 0; i < 10; i++ )); do
      mkdir $1/dir$i
      for (( j = 0; j < 40000; j++ )); do
        dd if=/dev/zero of=$1/dir$i/$j bs=4k count=4 &>/dev/null
      done &
    done
  }

  for dir in "$@"; do
    run_writers $dir
  done

  sleep 40
  time sync

Fix the problem by disregarding inodes dirtied after sync(2) was called
in the WB_SYNC_ALL pass.  To allow for this, sync_inodes_sb() now takes
a time stamp when sync has started which is used for setting up work for
flusher threads.

To give some numbers, when above script is run on two ext4 filesystems
on simple SATA drive, the average sync time from 10 runs is 267.549
seconds with standard deviation 104.799426.  With the patched kernel,
the average sync time from 10 runs is 2.995 seconds with standard
deviation 0.096.
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NFengguang Wu <fengguang.wu@intel.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c4a391b5
    • N
      tools/vm/page-types.c: support KPF_SOFTDIRTY bit · 46c77e2b
      由 Naoya Horiguchi 提交于 
      Soft dirty bit allows us to track which pages are written since the last
clear_ref (by "echo 4 > /proc/pid/clear_refs".) This is useful for
userspace applications to know their memory footprints.

Note that the kernel exposes this flag via bit[55] of /proc/pid/pagemap,
and the semantics is not a default one (scheduled to be the default in the
near future.) However, it shifts to the new semantics at the first
clear_ref, and the users of soft dirty bit always do it before utilizing
the bit, so that's not a big deal.  Users must avoid relying on the bit in
page-types before the first clear_ref.
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      46c77e2b
    • Z
      mm/sparsemem: use PAGES_PER_SECTION to remove redundant nr_pages parameter · 85b35fea
      由 Zhang Yanfei 提交于 
      For below functions,

- sparse_add_one_section()
- kmalloc_section_memmap()
- __kmalloc_section_memmap()
- __kfree_section_memmap()

they are always invoked to operate on one memory section, so it is
redundant to always pass a nr_pages parameter, which is the page numbers
in one section.  So we can directly use predefined macro PAGES_PER_SECTION
instead of passing the parameter.
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      85b35fea
    • D
      mm, mempolicy: make mpol_to_str robust and always succeed · 948927ee
      由 David Rientjes 提交于 
      mpol_to_str() should not fail.  Currently, it either fails because the
string buffer is too small or because a string hasn't been defined for a
mempolicy mode.

If a new mempolicy mode is introduced and no string is defined for it,
just warn and return "unknown".

If the buffer is too small, just truncate the string and return, the
same behavior as snprintf().

This also fixes a bug where there was no NULL-byte termination when doing
*p++ = '=' and *p++ ':' and maxlen has been reached.
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Chen Gang <gang.chen@asianux.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      948927ee
    • T
      cpu/mem hotplug: add try_online_node() for cpu_up() · 01b0f197
      由 Toshi Kani 提交于 
      cpu_up() has #ifdef CONFIG_MEMORY_HOTPLUG code blocks, which call
mem_online_node() to put its node online if offlined and then call
build_all_zonelists() to initialize the zone list.

These steps are specific to memory hotplug, and should be managed in
mm/memory_hotplug.c.  lock_memory_hotplug() should also be held for the
whole steps.

For this reason, this patch replaces mem_online_node() with
try_online_node(), which performs the whole steps with
lock_memory_hotplug() held.  try_online_node() is named after
try_offline_node() as they have similar purpose.

There is no functional change in this patch.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Reviewed-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      01b0f197
    • Q
      mm: add a helper function to check may oom condition · b9921ecd
      由 Qiang Huang 提交于 
      Use helper function to check if we need to deal with oom condition.
Signed-off-by: NQiang Huang <h.huangqiang@huawei.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b9921ecd
  3. 09 11月, 2013 1 次提交
  5. 07 11月, 2013 3 次提交
  7. 06 11月, 2013 1 次提交
  9. 05 11月, 2013 2 次提交
  11. 04 11月, 2013 2 次提交
  13. 01 11月, 2013 1 次提交
  15. 31 10月, 2013 2 次提交
    • S
      of: Move definition of of_find_next_cache_node into common code. · a3e31b45
      由 Sudeep KarkadaNagesha 提交于 
      Since the definition of_find_next_cache_node is architecture independent,
the existing definition in powerpc can be moved to driver/of/base.c

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: NSudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      a3e31b45
    • G
      percpu: fix this_cpu_sub() subtrahend casting for unsigneds · bd09d9a3
      由 Greg Thelen 提交于 
      this_cpu_sub() is implemented as negation and addition.

This patch casts the adjustment to the counter type before negation to
sign extend the adjustment.  This helps in cases where the counter type
is wider than an unsigned adjustment.  An alternative to this patch is
to declare such operations unsupported, but it seemed useful to avoid
surprises.

This patch specifically helps the following example:
  unsigned int delta = 1
  preempt_disable()
  this_cpu_write(long_counter, 0)
  this_cpu_sub(long_counter, delta)
  preempt_enable()

Before this change long_counter on a 64 bit machine ends with value
0xffffffff, rather than 0xffffffffffffffff.  This is because
this_cpu_sub(pcp, delta) boils down to this_cpu_add(pcp, -delta),
which is basically:
  long_counter = 0 + 0xffffffff

Also apply the same cast to:
  __this_cpu_sub()
  __this_cpu_sub_return()
  this_cpu_sub_return()

All percpu_test.ko passes, especially the following cases which
previously failed:

  l -= ui_one;
  __this_cpu_sub(long_counter, ui_one);
  CHECK(l, long_counter, -1);

  l -= ui_one;
  this_cpu_sub(long_counter, ui_one);
  CHECK(l, long_counter, -1);
  CHECK(l, long_counter, 0xffffffffffffffff);

  ul -= ui_one;
  __this_cpu_sub(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, -1);
  CHECK(ul, ulong_counter, 0xffffffffffffffff);

  ul = this_cpu_sub_return(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, 2);

  ul = __this_cpu_sub_return(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, 1);
Signed-off-by: NGreg Thelen <gthelen@google.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bd09d9a3
  17. 30 10月, 2013 7 次提交
  19. 29 10月, 2013 9 次提交
  21. 26 10月, 2013 3 次提交
  23. 24 10月, 2013 1 次提交