<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/kernel/events/uprobes.c, branch v3.19.4</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux</title>
<updated>2014-12-15T23:52:01+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-12-15T23:52:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=988adfdffdd43cfd841df734664727993076d7cb'/>
<id>988adfdffdd43cfd841df734664727993076d7cb</id>
<content type='text'>
Pull drm updates from Dave Airlie:
 "Highlights:

   - AMD KFD driver merge

     This is the AMD HSA interface for exposing a lowlevel interface for
     GPGPU use.  They have an open source userspace built on top of this
     interface, and the code looks as good as it was going to get out of
     tree.

   - Initial atomic modesetting work

     The need for an atomic modesetting interface to allow userspace to
     try and send a complete set of modesetting state to the driver has
     arisen, and been suffering from neglect this past year.  No more,
     the start of the common code and changes for msm driver to use it
     are in this tree.  Ongoing work to get the userspace ioctl finished
     and the code clean will probably wait until next kernel.

   - DisplayID 1.3 and tiled monitor exposed to userspace.

     Tiled monitor property is now exposed for userspace to make use of.

   - Rockchip drm driver merged.

   - imx gpu driver moved out of staging

  Other stuff:

   - core:
        panel - MIPI DSI + new panels.
        expose suggested x/y properties for virtual GPUs

   - i915:
        Initial Skylake (SKL) support
        gen3/4 reset work
        start of dri1/ums removal
        infoframe tracking
        fixes for lots of things.

   - nouveau:
        tegra k1 voltage support
        GM204 modesetting support
        GT21x memory reclocking work

   - radeon:
        CI dpm fixes
        GPUVM improvements
        Initial DPM fan control

   - rcar-du:
        HDMI support added
        removed some support for old boards
        slave encoder driver for Analog Devices adv7511

   - exynos:
        Exynos4415 SoC support

   - msm:
        a4xx gpu support
        atomic helper conversion

   - tegra:
        iommu support
        universal plane support
        ganged-mode DSI support

   - sti:
        HDMI i2c improvements

   - vmwgfx:
        some late fixes.

   - qxl:
        use suggested x/y properties"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (969 commits)
  drm: sti: fix module compilation issue
  drm/i915: save/restore GMBUS freq across suspend/resume on gen4
  drm: sti: correctly cleanup CRTC and planes
  drm: sti: add HQVDP plane
  drm: sti: add cursor plane
  drm: sti: enable auxiliary CRTC
  drm: sti: fix delay in VTG programming
  drm: sti: prepare sti_tvout to support auxiliary crtc
  drm: sti: use drm_crtc_vblank_{on/off} instead of drm_vblank_{on/off}
  drm: sti: fix hdmi avi infoframe
  drm: sti: remove event lock while disabling vblank
  drm: sti: simplify gdp code
  drm: sti: clear all mixer control
  drm: sti: remove gpio for HDMI hot plug detection
  drm: sti: allow to change hdmi ddc i2c adapter
  drm/doc: Document drm_add_modes_noedid() usage
  drm/i915: Remove '&amp; 0xffff' from the mask given to WA_REG()
  drm/i915: Invert the mask and val arguments in wa_add() and WA_REG()
  drm: Zero out DRM object memory upon cleanup
  drm/i915/bdw: Fix the write setting up the WIZ hashing mode
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull drm updates from Dave Airlie:
 "Highlights:

   - AMD KFD driver merge

     This is the AMD HSA interface for exposing a lowlevel interface for
     GPGPU use.  They have an open source userspace built on top of this
     interface, and the code looks as good as it was going to get out of
     tree.

   - Initial atomic modesetting work

     The need for an atomic modesetting interface to allow userspace to
     try and send a complete set of modesetting state to the driver has
     arisen, and been suffering from neglect this past year.  No more,
     the start of the common code and changes for msm driver to use it
     are in this tree.  Ongoing work to get the userspace ioctl finished
     and the code clean will probably wait until next kernel.

   - DisplayID 1.3 and tiled monitor exposed to userspace.

     Tiled monitor property is now exposed for userspace to make use of.

   - Rockchip drm driver merged.

   - imx gpu driver moved out of staging

  Other stuff:

   - core:
        panel - MIPI DSI + new panels.
        expose suggested x/y properties for virtual GPUs

   - i915:
        Initial Skylake (SKL) support
        gen3/4 reset work
        start of dri1/ums removal
        infoframe tracking
        fixes for lots of things.

   - nouveau:
        tegra k1 voltage support
        GM204 modesetting support
        GT21x memory reclocking work

   - radeon:
        CI dpm fixes
        GPUVM improvements
        Initial DPM fan control

   - rcar-du:
        HDMI support added
        removed some support for old boards
        slave encoder driver for Analog Devices adv7511

   - exynos:
        Exynos4415 SoC support

   - msm:
        a4xx gpu support
        atomic helper conversion

   - tegra:
        iommu support
        universal plane support
        ganged-mode DSI support

   - sti:
        HDMI i2c improvements

   - vmwgfx:
        some late fixes.

   - qxl:
        use suggested x/y properties"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (969 commits)
  drm: sti: fix module compilation issue
  drm/i915: save/restore GMBUS freq across suspend/resume on gen4
  drm: sti: correctly cleanup CRTC and planes
  drm: sti: add HQVDP plane
  drm: sti: add cursor plane
  drm: sti: enable auxiliary CRTC
  drm: sti: fix delay in VTG programming
  drm: sti: prepare sti_tvout to support auxiliary crtc
  drm: sti: use drm_crtc_vblank_{on/off} instead of drm_vblank_{on/off}
  drm: sti: fix hdmi avi infoframe
  drm: sti: remove event lock while disabling vblank
  drm: sti: simplify gdp code
  drm: sti: clear all mixer control
  drm: sti: remove gpio for HDMI hot plug detection
  drm: sti: allow to change hdmi ddc i2c adapter
  drm/doc: Document drm_add_modes_noedid() usage
  drm/i915: Remove '&amp; 0xffff' from the mask given to WA_REG()
  drm/i915: Invert the mask and val arguments in wa_add() and WA_REG()
  drm: Zero out DRM object memory upon cleanup
  drm/i915/bdw: Fix the write setting up the WIZ hashing mode
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>uprobes: share the i_mmap_rwsem</title>
<updated>2014-12-13T20:42:45+00:00</updated>
<author>
<name>Davidlohr Bueso</name>
<email>dave@stgolabs.net</email>
</author>
<published>2014-12-13T00:54:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4a23717a236b2ab31efb1651f586126789fc997f'/>
<id>4a23717a236b2ab31efb1651f586126789fc997f</id>
<content type='text'>
Both register and unregister call build_map_info() in order to create the
list of mappings before installing or removing breakpoints for every mm
which maps file backed memory.  As such, there is no reason to hold the
i_mmap_rwsem exclusively, so share it and allow concurrent readers to
build the mapping data.

Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Acked-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Both register and unregister call build_map_info() in order to create the
list of mappings before installing or removing breakpoints for every mm
which maps file backed memory.  As such, there is no reason to hold the
i_mmap_rwsem exclusively, so share it and allow concurrent readers to
build the mapping data.

Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Acked-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: convert i_mmap_mutex to rwsem</title>
<updated>2014-12-13T20:42:45+00:00</updated>
<author>
<name>Davidlohr Bueso</name>
<email>dave@stgolabs.net</email>
</author>
<published>2014-12-13T00:54:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c8c06efa8b552608493b7066c234cfa82c47fcea'/>
<id>c8c06efa8b552608493b7066c234cfa82c47fcea</id>
<content type='text'>
The i_mmap_mutex is a close cousin of the anon vma lock, both protecting
similar data, one for file backed pages and the other for anon memory.  To
this end, this lock can also be a rwsem.  In addition, there are some
important opportunities to share the lock when there are no tree
modifications.

This conversion is straightforward.  For now, all users take the write
lock.

[sfr@canb.auug.org.au: update fremap.c]
Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The i_mmap_mutex is a close cousin of the anon vma lock, both protecting
similar data, one for file backed pages and the other for anon memory.  To
this end, this lock can also be a rwsem.  In addition, there are some
important opportunities to share the lock when there are no tree
modifications.

This conversion is straightforward.  For now, all users take the write
lock.

[sfr@canb.auug.org.au: update fremap.c]
Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: use new helper functions around the i_mmap_mutex</title>
<updated>2014-12-13T20:42:45+00:00</updated>
<author>
<name>Davidlohr Bueso</name>
<email>dave@stgolabs.net</email>
</author>
<published>2014-12-13T00:54:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=83cde9e8ba95d180eaefefe834958fbf7008cf39'/>
<id>83cde9e8ba95d180eaefefe834958fbf7008cf39</id>
<content type='text'>
Convert all open coded mutex_lock/unlock calls to the
i_mmap_[lock/unlock]_write() helpers.

Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Acked-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Convert all open coded mutex_lock/unlock calls to the
i_mmap_[lock/unlock]_write() helpers.

Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Acked-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: "Kirill A. Shutemov" &lt;kirill@shutemov.name&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'v3.18-rc7' into drm-next</title>
<updated>2014-12-02T00:58:33+00:00</updated>
<author>
<name>Dave Airlie</name>
<email>airlied@redhat.com</email>
</author>
<published>2014-12-02T00:58:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e8115e79aa62b6ebdb3e8e61ca4092cc32938afc'/>
<id>e8115e79aa62b6ebdb3e8e61ca4092cc32938afc</id>
<content type='text'>
This fixes a bunch of conflicts prior to merging i915 tree.

Linux 3.18-rc7

Conflicts:
	drivers/gpu/drm/exynos/exynos_drm_drv.c
	drivers/gpu/drm/i915/i915_drv.c
	drivers/gpu/drm/i915/intel_pm.c
	drivers/gpu/drm/tegra/dc.c
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This fixes a bunch of conflicts prior to merging i915 tree.

Linux 3.18-rc7

Conflicts:
	drivers/gpu/drm/exynos/exynos_drm_drv.c
	drivers/gpu/drm/i915/i915_drv.c
	drivers/gpu/drm/i915/intel_pm.c
	drivers/gpu/drm/tegra/dc.c
</pre>
</div>
</content>
</entry>
<entry>
<title>uprobes, x86: Fix _TIF_UPROBE vs _TIF_NOTIFY_RESUME</title>
<updated>2014-11-23T22:25:28+00:00</updated>
<author>
<name>Andy Lutomirski</name>
<email>luto@amacapital.net</email>
</author>
<published>2014-11-21T21:26:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=82975bc6a6df743b9a01810fb32cb65d0ec5d60b'/>
<id>82975bc6a6df743b9a01810fb32cb65d0ec5d60b</id>
<content type='text'>
x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but
not on non-paranoid returns.  I suspect that this is a mistake and that
the code only works because int3 is paranoid.

Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround
for the x86 bug.  With that bug fixed, we can remove _TIF_NOTIFY_RESUME
from the uprobes code.

Reported-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: Andy Lutomirski &lt;luto@amacapital.net&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but
not on non-paranoid returns.  I suspect that this is a mistake and that
the code only works because int3 is paranoid.

Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround
for the x86 bug.  With that bug fixed, we can remove _TIF_NOTIFY_RESUME
from the uprobes code.

Reported-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: Andy Lutomirski &lt;luto@amacapital.net&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: memcontrol: rewrite charge API</title>
<updated>2014-08-08T22:57:17+00:00</updated>
<author>
<name>Johannes Weiner</name>
<email>hannes@cmpxchg.org</email>
</author>
<published>2014-08-08T21:19:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=00501b531c4723972aa11d6d4ebcf8d6552007c8'/>
<id>00501b531c4723972aa11d6d4ebcf8d6552007c8</id>
<content type='text'>
These patches rework memcg charge lifetime to integrate more naturally
with the lifetime of user pages.  This drastically simplifies the code and
reduces charging and uncharging overhead.  The most expensive part of
charging and uncharging is the page_cgroup bit spinlock, which is removed
entirely after this series.

Here are the top-10 profile entries of a stress test that reads a 128G
sparse file on a freshly booted box, without even a dedicated cgroup (i.e.
 executing in the root memcg).  Before:

    15.36%              cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.31%              cat  [kernel.kallsyms]   [k] memset
    11.48%              cat  [kernel.kallsyms]   [k] do_mpage_readpage
     4.23%              cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.38%              cat  [kernel.kallsyms]   [k] put_page
     2.32%              cat  [kernel.kallsyms]   [k] __mem_cgroup_commit_charge
     2.18%          kswapd0  [kernel.kallsyms]   [k] __mem_cgroup_uncharge_common
     1.92%          kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.86%              cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.62%              cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn

After:

    15.67%           cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.48%           cat  [kernel.kallsyms]   [k] memset
    11.42%           cat  [kernel.kallsyms]   [k] do_mpage_readpage
     3.98%           cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.46%           cat  [kernel.kallsyms]   [k] put_page
     2.13%       kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.88%           cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.67%           cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn
     1.39%       kswapd0  [kernel.kallsyms]   [k] free_pcppages_bulk
     1.30%           cat  [kernel.kallsyms]   [k] kfree

As you can see, the memcg footprint has shrunk quite a bit.

   text    data     bss     dec     hex filename
  37970    9892     400   48262    bc86 mm/memcontrol.o.old
  35239    9892     400   45531    b1db mm/memcontrol.o

This patch (of 4):

The memcg charge API charges pages before they are rmapped - i.e.  have an
actual "type" - and so every callsite needs its own set of charge and
uncharge functions to know what type is being operated on.  Worse,
uncharge has to happen from a context that is still type-specific, rather
than at the end of the page's lifetime with exclusive access, and so
requires a lot of synchronization.

Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:

  mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
  pages from the memcg if necessary.

  mem_cgroup_commit_charge() commits the page to the charge once it
  has a valid page-&gt;mapping and PageAnon() reliably tells the type.

  mem_cgroup_cancel_charge() aborts the transaction.

This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.

As pages need to be committed after rmap is established but before they
are added to the LRU, page_add_new_anon_rmap() must stop doing LRU
additions again.  Revive lru_cache_add_active_or_unevictable().

[hughd@google.com: fix shmem_unuse]
[hughd@google.com: Add comments on the private use of -EAGAIN]
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Vladimir Davydov &lt;vdavydov@parallels.com&gt;
Signed-off-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Naoya Horiguchi &lt;n-horiguchi@ah.jp.nec.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
These patches rework memcg charge lifetime to integrate more naturally
with the lifetime of user pages.  This drastically simplifies the code and
reduces charging and uncharging overhead.  The most expensive part of
charging and uncharging is the page_cgroup bit spinlock, which is removed
entirely after this series.

Here are the top-10 profile entries of a stress test that reads a 128G
sparse file on a freshly booted box, without even a dedicated cgroup (i.e.
 executing in the root memcg).  Before:

    15.36%              cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.31%              cat  [kernel.kallsyms]   [k] memset
    11.48%              cat  [kernel.kallsyms]   [k] do_mpage_readpage
     4.23%              cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.38%              cat  [kernel.kallsyms]   [k] put_page
     2.32%              cat  [kernel.kallsyms]   [k] __mem_cgroup_commit_charge
     2.18%          kswapd0  [kernel.kallsyms]   [k] __mem_cgroup_uncharge_common
     1.92%          kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.86%              cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.62%              cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn

After:

    15.67%           cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.48%           cat  [kernel.kallsyms]   [k] memset
    11.42%           cat  [kernel.kallsyms]   [k] do_mpage_readpage
     3.98%           cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.46%           cat  [kernel.kallsyms]   [k] put_page
     2.13%       kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.88%           cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.67%           cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn
     1.39%       kswapd0  [kernel.kallsyms]   [k] free_pcppages_bulk
     1.30%           cat  [kernel.kallsyms]   [k] kfree

As you can see, the memcg footprint has shrunk quite a bit.

   text    data     bss     dec     hex filename
  37970    9892     400   48262    bc86 mm/memcontrol.o.old
  35239    9892     400   45531    b1db mm/memcontrol.o

This patch (of 4):

The memcg charge API charges pages before they are rmapped - i.e.  have an
actual "type" - and so every callsite needs its own set of charge and
uncharge functions to know what type is being operated on.  Worse,
uncharge has to happen from a context that is still type-specific, rather
than at the end of the page's lifetime with exclusive access, and so
requires a lot of synchronization.

Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:

  mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
  pages from the memcg if necessary.

  mem_cgroup_commit_charge() commits the page to the charge once it
  has a valid page-&gt;mapping and PageAnon() reliably tells the type.

  mem_cgroup_cancel_charge() aborts the transaction.

This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.

As pages need to be committed after rmap is established but before they
are added to the LRU, page_add_new_anon_rmap() must stop doing LRU
additions again.  Revive lru_cache_add_active_or_unevictable().

[hughd@google.com: fix shmem_unuse]
[hughd@google.com: Add comments on the private use of -EAGAIN]
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Vladimir Davydov &lt;vdavydov@parallels.com&gt;
Signed-off-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Naoya Horiguchi &lt;n-horiguchi@ah.jp.nec.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>uprobes: Change unregister/apply to WARN() if uprobe/consumer is gone</title>
<updated>2014-06-30T17:22:15+00:00</updated>
<author>
<name>Oleg Nesterov</name>
<email>oleg@redhat.com</email>
</author>
<published>2014-06-27T17:01:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=06d0713904e508f765e0d7146c14b67bbd248fe7'/>
<id>06d0713904e508f765e0d7146c14b67bbd248fe7</id>
<content type='text'>
Add WARN_ON's into uprobe_unregister() and uprobe_apply() to ensure
that nobody tries to play with the dead uprobe/consumer. This helps
to catch the bugs like the one fixed by the previous patch.

In the longer term we should fix this poorly designed interface.
uprobe_register() should return "struct uprobe *" which should be
passed to apply/unregister. Plus other semantic changes, see the
changelog in commit 41ccba029e94.

Link: http://lkml.kernel.org/p/20140627170140.GA18322@redhat.com

Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Signed-off-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add WARN_ON's into uprobe_unregister() and uprobe_apply() to ensure
that nobody tries to play with the dead uprobe/consumer. This helps
to catch the bugs like the one fixed by the previous patch.

In the longer term we should fix this poorly designed interface.
uprobe_register() should return "struct uprobe *" which should be
passed to apply/unregister. Plus other semantic changes, see the
changelog in commit 41ccba029e94.

Link: http://lkml.kernel.org/p/20140627170140.GA18322@redhat.com

Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Signed-off-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-06-13T02:18:49+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-06-13T02:18:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3737a12761636ebde0f09ef49daebb8eed18cc8a'/>
<id>3737a12761636ebde0f09ef49daebb8eed18cc8a</id>
<content type='text'>
Pull more perf updates from Ingo Molnar:
 "A second round of perf updates:

   - wide reaching kprobes sanitization and robustization, with the hope
     of fixing all 'probe this function crashes the kernel' bugs, by
     Masami Hiramatsu.

   - uprobes updates from Oleg Nesterov: tmpfs support, corner case
     fixes and robustization work.

   - perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo
     et al:
        * Add support to accumulate hist periods (Namhyung Kim)
        * various fixes, refactorings and enhancements"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
  perf: Differentiate exec() and non-exec() comm events
  perf: Fix perf_event_comm() vs. exec() assumption
  uprobes/x86: Rename arch_uprobe-&gt;def to -&gt;defparam, minor comment updates
  perf/documentation: Add description for conditional branch filter
  perf/x86: Add conditional branch filtering support
  perf/tool: Add conditional branch filter 'cond' to perf record
  perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND'
  uprobes: Teach copy_insn() to support tmpfs
  uprobes: Shift -&gt;readpage check from __copy_insn() to uprobe_register()
  perf/x86: Use common PMU interrupt disabled code
  perf/ARM: Use common PMU interrupt disabled code
  perf: Disable sampled events if no PMU interrupt
  perf: Fix use after free in perf_remove_from_context()
  perf tools: Fix 'make help' message error
  perf record: Fix poll return value propagation
  perf tools: Move elide bool into perf_hpp_fmt struct
  perf tools: Remove elide setup for SORT_MODE__MEMORY mode
  perf tools: Fix "==" into "=" in ui_browser__warning assignment
  perf tools: Allow overriding sysfs and proc finding with env var
  perf tools: Consider header files outside perf directory in tags target
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull more perf updates from Ingo Molnar:
 "A second round of perf updates:

   - wide reaching kprobes sanitization and robustization, with the hope
     of fixing all 'probe this function crashes the kernel' bugs, by
     Masami Hiramatsu.

   - uprobes updates from Oleg Nesterov: tmpfs support, corner case
     fixes and robustization work.

   - perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo
     et al:
        * Add support to accumulate hist periods (Namhyung Kim)
        * various fixes, refactorings and enhancements"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
  perf: Differentiate exec() and non-exec() comm events
  perf: Fix perf_event_comm() vs. exec() assumption
  uprobes/x86: Rename arch_uprobe-&gt;def to -&gt;defparam, minor comment updates
  perf/documentation: Add description for conditional branch filter
  perf/x86: Add conditional branch filtering support
  perf/tool: Add conditional branch filter 'cond' to perf record
  perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND'
  uprobes: Teach copy_insn() to support tmpfs
  uprobes: Shift -&gt;readpage check from __copy_insn() to uprobe_register()
  perf/x86: Use common PMU interrupt disabled code
  perf/ARM: Use common PMU interrupt disabled code
  perf: Disable sampled events if no PMU interrupt
  perf: Fix use after free in perf_remove_from_context()
  perf tools: Fix 'make help' message error
  perf record: Fix poll return value propagation
  perf tools: Move elide bool into perf_hpp_fmt struct
  perf tools: Remove elide setup for SORT_MODE__MEMORY mode
  perf tools: Fix "==" into "=" in ui_browser__warning assignment
  perf tools: Allow overriding sysfs and proc finding with env var
  perf tools: Consider header files outside perf directory in tags target
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next</title>
<updated>2014-06-05T22:57:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-06-05T22:57:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=eb3d3ec567e868c8a3bfbfdfc9465ffd52983d11'/>
<id>eb3d3ec567e868c8a3bfbfdfc9465ffd52983d11</id>
<content type='text'>
Pull ARM updates from Russell King:

 - Major clean-up of the L2 cache support code.  The existing mess was
   becoming rather unmaintainable through all the additions that others
   have done over time.  This turns it into a much nicer structure, and
   implements a few performance improvements as well.

 - Clean up some of the CP15 control register tweaks for alignment
   support, moving some code and data into alignment.c

 - DMA properties for ARM, from Santosh and reviewed by DT people.  This
   adds DT properties to specify bus translations we can't discover
   automatically, and to indicate whether devices are coherent.

 - Hibernation support for ARM

 - Make ftrace work with read-only text in modules

 - add suspend support for PJ4B CPUs

 - rework interrupt masking for undefined instruction handling, which
   allows us to enable interrupts earlier in the handling of these
   exceptions.

 - support for big endian page tables

 - fix stacktrace support to exclude stacktrace functions from the
   trace, and add save_stack_trace_regs() implementation so that kprobes
   can record stack traces.

 - Add support for the Cortex-A17 CPU.

 - Remove last vestiges of ARM710 support.

 - Removal of ARM "meminfo" structure, finally converting us solely to
   memblock to handle the early memory initialisation.

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (142 commits)
  ARM: ensure C page table setup code follows assembly code (part II)
  ARM: ensure C page table setup code follows assembly code
  ARM: consolidate last remaining open-coded alignment trap enable
  ARM: remove global cr_no_alignment
  ARM: remove CPU_CP15 conditional from alignment.c
  ARM: remove unused adjust_cr() function
  ARM: move "noalign" command line option to alignment.c
  ARM: provide common method to clear bits in CPU control register
  ARM: 8025/1: Get rid of meminfo
  ARM: 8060/1: mm: allow sub-architectures to override PCI I/O memory type
  ARM: 8066/1: correction for ARM patch 8031/2
  ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation
  ARM: 8065/1: remove last use of CONFIG_CPU_ARM710
  ARM: 8062/1: Modify ldrt fixup handler to re-execute the userspace instruction
  ARM: 8047/1: rwsem: use asm-generic rwsem implementation
  ARM: l2c: trial at enabling some Cortex-A9 optimisations
  ARM: l2c: add warnings for stuff modifying aux_ctrl register values
  ARM: l2c: print a warning with L2C-310 caches if the cache size is modified
  ARM: l2c: remove old .set_debug method
  ARM: l2c: kill L2X0_AUX_CTRL_MASK before anyone else makes use of this
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ARM updates from Russell King:

 - Major clean-up of the L2 cache support code.  The existing mess was
   becoming rather unmaintainable through all the additions that others
   have done over time.  This turns it into a much nicer structure, and
   implements a few performance improvements as well.

 - Clean up some of the CP15 control register tweaks for alignment
   support, moving some code and data into alignment.c

 - DMA properties for ARM, from Santosh and reviewed by DT people.  This
   adds DT properties to specify bus translations we can't discover
   automatically, and to indicate whether devices are coherent.

 - Hibernation support for ARM

 - Make ftrace work with read-only text in modules

 - add suspend support for PJ4B CPUs

 - rework interrupt masking for undefined instruction handling, which
   allows us to enable interrupts earlier in the handling of these
   exceptions.

 - support for big endian page tables

 - fix stacktrace support to exclude stacktrace functions from the
   trace, and add save_stack_trace_regs() implementation so that kprobes
   can record stack traces.

 - Add support for the Cortex-A17 CPU.

 - Remove last vestiges of ARM710 support.

 - Removal of ARM "meminfo" structure, finally converting us solely to
   memblock to handle the early memory initialisation.

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (142 commits)
  ARM: ensure C page table setup code follows assembly code (part II)
  ARM: ensure C page table setup code follows assembly code
  ARM: consolidate last remaining open-coded alignment trap enable
  ARM: remove global cr_no_alignment
  ARM: remove CPU_CP15 conditional from alignment.c
  ARM: remove unused adjust_cr() function
  ARM: move "noalign" command line option to alignment.c
  ARM: provide common method to clear bits in CPU control register
  ARM: 8025/1: Get rid of meminfo
  ARM: 8060/1: mm: allow sub-architectures to override PCI I/O memory type
  ARM: 8066/1: correction for ARM patch 8031/2
  ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation
  ARM: 8065/1: remove last use of CONFIG_CPU_ARM710
  ARM: 8062/1: Modify ldrt fixup handler to re-execute the userspace instruction
  ARM: 8047/1: rwsem: use asm-generic rwsem implementation
  ARM: l2c: trial at enabling some Cortex-A9 optimisations
  ARM: l2c: add warnings for stuff modifying aux_ctrl register values
  ARM: l2c: print a warning with L2C-310 caches if the cache size is modified
  ARM: l2c: remove old .set_debug method
  ARM: l2c: kill L2X0_AUX_CTRL_MASK before anyone else makes use of this
  ...
</pre>
</div>
</content>
</entry>
</feed>
