<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux/rmap.h, branch v3.17</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v3.17</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v3.17'/>
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<updated>2014-06-04T23:54:12Z</updated>
<entry>
<title>mm/rmap.c: cleanup ttu_flags</title>
<updated>2014-06-04T23:54:12Z</updated>
<author>
<name>Konstantin Khlebnikov</name>
<email>koct9i@gmail.com</email>
</author>
<published>2014-06-04T23:10:52Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=daa5ba768b9e15da8867824d2f1e8d455f1acac2'/>
<id>urn:sha1:daa5ba768b9e15da8867824d2f1e8d455f1acac2</id>
<content type='text'>
Transform action part of ttu_flags into individiual bits.  These flags
aren't part of any uses-space visible api or even trace events.

Signed-off-by: Konstantin Khlebnikov &lt;koct9i@gmail.com&gt;
Cc: Rik van Riel &lt;riel@redhat.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>
</entry>
<entry>
<title>mm/rmap.c: make page_referenced_one() and try_to_unmap_one() static</title>
<updated>2014-06-04T23:54:05Z</updated>
<author>
<name>Kirill A. Shutemov</name>
<email>kirill.shutemov@linux.intel.com</email>
</author>
<published>2014-06-04T23:08:17Z</published>
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<id>urn:sha1:ac7695012a6f3269acd80d6c2b2218a6769edbf3</id>
<content type='text'>
KSM was converted to use rmap_walk() and now nobody uses these functions
outside mm/rmap.c.

Let's covert them back to static.

Signed-off-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.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>
</entry>
<entry>
<title>mm: fix swapops.h:131 bug if remap_file_pages raced migration</title>
<updated>2014-03-21T05:09:09Z</updated>
<author>
<name>Hugh Dickins</name>
<email>hughd@google.com</email>
</author>
<published>2014-03-21T04:52:17Z</published>
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<id>urn:sha1:7e09e738afd21ef99f047425fc0b0c9be8b03254</id>
<content type='text'>
Add remove_linear_migration_ptes_from_nonlinear(), to fix an interesting
little include/linux/swapops.h:131 BUG_ON(!PageLocked) found by trinity:
indicating that remove_migration_ptes() failed to find one of the
migration entries that was temporarily inserted.

The problem comes from remap_file_pages()'s switch from vma_interval_tree
(good for inserting the migration entry) to i_mmap_nonlinear list (no good
for locating it again); but can only be a problem if the remap_file_pages()
range does not cover the whole of the vma (zap_pte() clears the range).

remove_migration_ptes() needs a file_nonlinear method to go down the
i_mmap_nonlinear list, applying linear location to look for migration
entries in those vmas too, just in case there was this race.

The file_nonlinear method does need rmap_walk_control.arg to do this;
but it never needed vma passed in - vma comes from its own iteration.

Reported-and-tested-by: Dave Jones &lt;davej@redhat.com&gt;
Reported-and-tested-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
Signed-off-by: Hugh Dickins &lt;hughd@google.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm/rmap: use rmap_walk() in page_referenced()</title>
<updated>2014-01-22T00:19:45Z</updated>
<author>
<name>Joonsoo Kim</name>
<email>iamjoonsoo.kim@lge.com</email>
</author>
<published>2014-01-21T23:49:53Z</published>
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<id>urn:sha1:9f32624be943538983eb0f18b73a9052d1493c80</id>
<content type='text'>
Now, we have an infrastructure in rmap_walk() to handle difference from
variants of rmap traversing functions.

So, just use it in page_referenced().

In this patch, I change following things.

1. remove some variants of rmap traversing functions.
	cf&gt; page_referenced_ksm, page_referenced_anon,
	page_referenced_file

2. introduce new struct page_referenced_arg and pass it to
   page_referenced_one(), main function of rmap_walk, in order to count
   reference, to store vm_flags and to check finish condition.

3. mechanical change to use rmap_walk() in page_referenced().

[liwanp@linux.vnet.ibm.com: fix BUG at rmap_walk]
Signed-off-by: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Reviewed-by: Naoya Horiguchi &lt;n-horiguchi@ah.jp.nec.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Hillf Danton &lt;dhillf@gmail.com&gt;
Signed-off-by: Wanpeng Li &lt;liwanp@linux.vnet.ibm.com&gt;
Cc: Sasha Levin &lt;sasha.levin@oracle.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>
</entry>
<entry>
<title>mm/rmap: use rmap_walk() in try_to_unmap()</title>
<updated>2014-01-22T00:19:45Z</updated>
<author>
<name>Joonsoo Kim</name>
<email>iamjoonsoo.kim@lge.com</email>
</author>
<published>2014-01-21T23:49:50Z</published>
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<id>urn:sha1:52629506420ce32997f1fba0a1ab2f1aaa9a4f79</id>
<content type='text'>
Now, we have an infrastructure in rmap_walk() to handle difference from
variants of rmap traversing functions.

So, just use it in try_to_unmap().

In this patch, I change following things.

1. enable rmap_walk() if !CONFIG_MIGRATION.
2. mechanical change to use rmap_walk() in try_to_unmap().

Signed-off-by: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Reviewed-by: Naoya Horiguchi &lt;n-horiguchi@ah.jp.nec.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Hillf Danton &lt;dhillf@gmail.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>
</entry>
<entry>
<title>mm/rmap: extend rmap_walk_xxx() to cope with different cases</title>
<updated>2014-01-22T00:19:45Z</updated>
<author>
<name>Joonsoo Kim</name>
<email>iamjoonsoo.kim@lge.com</email>
</author>
<published>2014-01-21T23:49:49Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0dd1c7bbce8d1d142bb25aefaa50262dfd77cb78'/>
<id>urn:sha1:0dd1c7bbce8d1d142bb25aefaa50262dfd77cb78</id>
<content type='text'>
There are a lot of common parts in traversing functions, but there are
also a little of uncommon parts in it.  By assigning proper function
pointer on each rmap_walker_control, we can handle these difference
correctly.

Following are differences we should handle.

1. difference of lock function in anon mapping case
2. nonlinear handling in file mapping case
3. prechecked condition:
	checking memcg in page_referenced(),
	checking VM_SHARE in page_mkclean()
	checking temporary vma in try_to_unmap()
4. exit condition:
	checking page_mapped() in try_to_unmap()

So, in this patch, I introduce 4 function pointers to handle above
differences.

Signed-off-by: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Cc: Naoya Horiguchi &lt;n-horiguchi@ah.jp.nec.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Hillf Danton &lt;dhillf@gmail.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>
</entry>
<entry>
<title>mm/rmap: make rmap_walk to get the rmap_walk_control argument</title>
<updated>2014-01-22T00:19:45Z</updated>
<author>
<name>Joonsoo Kim</name>
<email>iamjoonsoo.kim@lge.com</email>
</author>
<published>2014-01-21T23:49:48Z</published>
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<id>urn:sha1:051ac83adf69eea4f57a97356e4282e395a5fa6d</id>
<content type='text'>
In each rmap traverse case, there is some difference so that we need
function pointers and arguments to them in order to handle these

For this purpose, struct rmap_walk_control is introduced in this patch,
and will be extended in following patch.  Introducing and extending are
separate, because it clarify changes.

Signed-off-by: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Reviewed-by: Naoya Horiguchi &lt;n-horiguchi@ah.jp.nec.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Hillf Danton &lt;dhillf@gmail.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>
</entry>
<entry>
<title>mm/rmap: rename anon_vma_unlock() =&gt; anon_vma_unlock_write()</title>
<updated>2013-02-24T01:50:17Z</updated>
<author>
<name>Konstantin Khlebnikov</name>
<email>khlebnikov@openvz.org</email>
</author>
<published>2013-02-23T00:34:40Z</published>
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<id>urn:sha1:08b52706d505658eac0962d215ff697f898bbc13</id>
<content type='text'>
The comment in commit 4fc3f1d66b1e ("mm/rmap, migration: Make
rmap_walk_anon() and try_to_unmap_anon() more scalable") says:

| Rename anon_vma_[un]lock() =&gt; anon_vma_[un]lock_write(),
| to make it clearer that it's an exclusive write-lock in
| that case - suggested by Rik van Riel.

But that commit renames only anon_vma_lock()

Signed-off-by: Konstantin Khlebnikov &lt;khlebnikov@openvz.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.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>
</entry>
<entry>
<title>mm/rmap, migration: Make rmap_walk_anon() and try_to_unmap_anon() more scalable</title>
<updated>2012-12-11T14:43:00Z</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2012-12-02T19:56:50Z</published>
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<id>urn:sha1:4fc3f1d66b1ef0d7b8dc11f4ff1cc510f78b37d6</id>
<content type='text'>
rmap_walk_anon() and try_to_unmap_anon() appears to be too
careful about locking the anon vma: while it needs protection
against anon vma list modifications, it does not need exclusive
access to the list itself.

Transforming this exclusive lock to a read-locked rwsem removes
a global lock from the hot path of page-migration intense
threaded workloads which can cause pathological performance like
this:

    96.43%        process 0  [kernel.kallsyms]  [k] perf_trace_sched_switch
                  |
                  --- perf_trace_sched_switch
                      __schedule
                      schedule
                      schedule_preempt_disabled
                      __mutex_lock_common.isra.6
                      __mutex_lock_slowpath
                      mutex_lock
                     |
                     |--50.61%-- rmap_walk
                     |          move_to_new_page
                     |          migrate_pages
                     |          migrate_misplaced_page
                     |          __do_numa_page.isra.69
                     |          handle_pte_fault
                     |          handle_mm_fault
                     |          __do_page_fault
                     |          do_page_fault
                     |          page_fault
                     |          __memset_sse2
                     |          |
                     |           --100.00%-- worker_thread
                     |                     |
                     |                      --100.00%-- start_thread
                     |
                      --49.39%-- page_lock_anon_vma
                                try_to_unmap_anon
                                try_to_unmap
                                migrate_pages
                                migrate_misplaced_page
                                __do_numa_page.isra.69
                                handle_pte_fault
                                handle_mm_fault
                                __do_page_fault
                                do_page_fault
                                page_fault
                                __memset_sse2
                                |
                                 --100.00%-- worker_thread
                                           start_thread

With this change applied the profile is now nicely flat
and there's no anon-vma related scheduling/blocking.

Rename anon_vma_[un]lock() =&gt; anon_vma_[un]lock_write(),
to make it clearer that it's an exclusive write-lock in
that case - suggested by Rik van Riel.

Suggested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Paul Turner &lt;pjt@google.com&gt;
Cc: Lee Schermerhorn &lt;Lee.Schermerhorn@hp.com&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
</content>
</entry>
<entry>
<title>mm/rmap: Convert the struct anon_vma::mutex to an rwsem</title>
<updated>2012-12-11T14:43:00Z</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2012-12-02T19:56:46Z</published>
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<id>urn:sha1:5a505085f043e8380f83610f79642853c051e2f1</id>
<content type='text'>
Convert the struct anon_vma::mutex to an rwsem, which will help
in solving a page-migration scalability problem. (Addressed in
a separate patch.)

The conversion is simple and straightforward: in every case
where we mutex_lock()ed we'll now down_write().

Suggested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Paul Turner &lt;pjt@google.com&gt;
Cc: Lee Schermerhorn &lt;Lee.Schermerhorn@hp.com&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
</content>
</entry>
</feed>
