<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/fs/proc/task_mmu.c, branch linux-5.7.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>proc: inline m_next_vma into m_next</title>
<updated>2020-04-07T17:43:42+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2020-04-07T03:09:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fad955009c2ba49e2eac98926ad5cce48b777e7e'/>
<id>fad955009c2ba49e2eac98926ad5cce48b777e7e</id>
<content type='text'>
It's clearer to just put this inline.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-5-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It's clearer to just put this inline.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-5-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>proc: use ppos instead of m-&gt;version</title>
<updated>2020-04-07T17:43:42+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2020-04-07T03:09:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4781f2c3abddc400cfdb6ed18c2bf655d402efb5'/>
<id>4781f2c3abddc400cfdb6ed18c2bf655d402efb5</id>
<content type='text'>
The ppos is a private cursor, just like m-&gt;version.  Use the canonical
cursor, not a special one.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-3-adobriyan@gmail.com
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 ppos is a private cursor, just like m-&gt;version.  Use the canonical
cursor, not a special one.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-3-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>proc: remove m_cache_vma</title>
<updated>2020-04-07T17:43:42+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2020-04-07T03:09:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c2e88d22e8ea698c183c6c36485c134742b99838'/>
<id>c2e88d22e8ea698c183c6c36485c134742b99838</id>
<content type='text'>
Instead of setting m-&gt;version in the show method, set it in m_next(),
where it should be.  Also remove the fallback code for failing to find a
vma, or version being zero.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-2-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of setting m-&gt;version in the show method, set it in m_next(),
where it should be.  Also remove the fallback code for failing to find a
vma, or version being zero.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-2-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>proc: inline vma_stop into m_stop</title>
<updated>2020-04-07T17:43:42+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2020-04-07T03:09:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d07ded611e46d276d41dafcbd6abc9dd7ab51a7f'/>
<id>d07ded611e46d276d41dafcbd6abc9dd7ab51a7f</id>
<content type='text'>
Instead of calling vma_stop() from m_start() and m_next(), do its work
in m_stop().

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-1-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of calling vma_stop() from m_start() and m_next(), do its work
in m_stop().

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20200317193201.9924-1-adobriyan@gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: pagewalk: add 'depth' parameter to pte_hole</title>
<updated>2020-02-04T03:05:25+00:00</updated>
<author>
<name>Steven Price</name>
<email>steven.price@arm.com</email>
</author>
<published>2020-02-04T01:36:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b7a16c7ad790d0ecb44dcb08a6a75d0d0455ab5f'/>
<id>b7a16c7ad790d0ecb44dcb08a6a75d0d0455ab5f</id>
<content type='text'>
The pte_hole() callback is called at multiple levels of the page tables.
Code dumping the kernel page tables needs to know what at what depth the
missing entry is.  Add this is an extra parameter to pte_hole().  When the
depth isn't know (e.g.  processing a vma) then -1 is passed.

The depth that is reported is the actual level where the entry is missing
(ignoring any folding that is in place), i.e.  any levels where
PTRS_PER_P?D is set to 1 are ignored.

Note that depth starts at 0 for a PGD so that PUD/PMD/PTE retain their
natural numbers as levels 2/3/4.

Link: http://lkml.kernel.org/r/20191218162402.45610-16-steven.price@arm.com
Signed-off-by: Steven Price &lt;steven.price@arm.com&gt;
Tested-by: Zong Li &lt;zong.li@sifive.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: James Morse &lt;james.morse@arm.com&gt;
Cc: Jerome Glisse &lt;jglisse@redhat.com&gt;
Cc: "Liang, Kan" &lt;kan.liang@linux.intel.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&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 pte_hole() callback is called at multiple levels of the page tables.
Code dumping the kernel page tables needs to know what at what depth the
missing entry is.  Add this is an extra parameter to pte_hole().  When the
depth isn't know (e.g.  processing a vma) then -1 is passed.

The depth that is reported is the actual level where the entry is missing
(ignoring any folding that is in place), i.e.  any levels where
PTRS_PER_P?D is set to 1 are ignored.

Note that depth starts at 0 for a PGD so that PUD/PMD/PTE retain their
natural numbers as levels 2/3/4.

Link: http://lkml.kernel.org/r/20191218162402.45610-16-steven.price@arm.com
Signed-off-by: Steven Price &lt;steven.price@arm.com&gt;
Tested-by: Zong Li &lt;zong.li@sifive.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: James Morse &lt;james.morse@arm.com&gt;
Cc: Jerome Glisse &lt;jglisse@redhat.com&gt;
Cc: "Liang, Kan" &lt;kan.liang@linux.intel.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&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,thp: stats for file backed THP</title>
<updated>2019-09-24T22:54:11+00:00</updated>
<author>
<name>Song Liu</name>
<email>songliubraving@fb.com</email>
</author>
<published>2019-09-23T22:37:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=60fbf0ab5da1c360e02b7f7d882bf1c0d8f7e32a'/>
<id>60fbf0ab5da1c360e02b7f7d882bf1c0d8f7e32a</id>
<content type='text'>
In preparation for non-shmem THP, this patch adds a few stats and exposes
them in /proc/meminfo, /sys/bus/node/devices/&lt;node&gt;/meminfo, and
/proc/&lt;pid&gt;/task/&lt;tid&gt;/smaps.

This patch is mostly a rewrite of Kirill A.  Shutemov's earlier version:
https://lkml.kernel.org/r/20170126115819.58875-5-kirill.shutemov@linux.intel.com/

Link: http://lkml.kernel.org/r/20190801184244.3169074-5-songliubraving@fb.com
Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Acked-by: Rik van Riel &lt;riel@surriel.com&gt;
Acked-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Hillf Danton &lt;hdanton@sina.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: William Kucharski &lt;william.kucharski@oracle.com&gt;
Cc: Oleg Nesterov &lt;oleg@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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In preparation for non-shmem THP, this patch adds a few stats and exposes
them in /proc/meminfo, /sys/bus/node/devices/&lt;node&gt;/meminfo, and
/proc/&lt;pid&gt;/task/&lt;tid&gt;/smaps.

This patch is mostly a rewrite of Kirill A.  Shutemov's earlier version:
https://lkml.kernel.org/r/20170126115819.58875-5-kirill.shutemov@linux.intel.com/

Link: http://lkml.kernel.org/r/20190801184244.3169074-5-songliubraving@fb.com
Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Acked-by: Rik van Riel &lt;riel@surriel.com&gt;
Acked-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Hillf Danton &lt;hdanton@sina.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: William Kucharski &lt;william.kucharski@oracle.com&gt;
Cc: Oleg Nesterov &lt;oleg@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;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: introduce compound_nr()</title>
<updated>2019-09-24T22:54:08+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2019-09-23T22:34:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d8c6546b1aea843fbeb4d54a1202f1adda6504be'/>
<id>d8c6546b1aea843fbeb4d54a1202f1adda6504be</id>
<content type='text'>
Replace 1 &lt;&lt; compound_order(page) with compound_nr(page).  Minor
improvements in readability.

Link: http://lkml.kernel.org/r/20190721104612.19120-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Acked-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.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>
Replace 1 &lt;&lt; compound_order(page) with compound_nr(page).  Minor
improvements in readability.

Link: http://lkml.kernel.org/r/20190721104612.19120-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Acked-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.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>pagewalk: separate function pointers from iterator data</title>
<updated>2019-09-07T07:28:04+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-08-28T14:19:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7b86ac3371b70c3fd8fd95501719beb1faab719f'/>
<id>7b86ac3371b70c3fd8fd95501719beb1faab719f</id>
<content type='text'>
The mm_walk structure currently mixed data and code.  Split out the
operations vectors into a new mm_walk_ops structure, and while we are
changing the API also declare the mm_walk structure inside the
walk_page_range and walk_page_vma functions.

Based on patch from Linus Torvalds.

Link: https://lore.kernel.org/r/20190828141955.22210-3-hch@lst.de
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Thomas Hellstrom &lt;thellstrom@vmware.com&gt;
Reviewed-by: Steven Price &lt;steven.price@arm.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The mm_walk structure currently mixed data and code.  Split out the
operations vectors into a new mm_walk_ops structure, and while we are
changing the API also declare the mm_walk structure inside the
walk_page_range and walk_page_vma functions.

Based on patch from Linus Torvalds.

Link: https://lore.kernel.org/r/20190828141955.22210-3-hch@lst.de
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Thomas Hellstrom &lt;thellstrom@vmware.com&gt;
Reviewed-by: Steven Price &lt;steven.price@arm.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: split out a new pagewalk.h header from mm.h</title>
<updated>2019-09-07T07:28:04+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-08-28T14:19:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a520110e4a15ceb385304d9cab22bb51438f6080'/>
<id>a520110e4a15ceb385304d9cab22bb51438f6080</id>
<content type='text'>
Add a new header for the two handful of users of the walk_page_range /
walk_page_vma interface instead of polluting all users of mm.h with it.

Link: https://lore.kernel.org/r/20190828141955.22210-2-hch@lst.de
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Thomas Hellstrom &lt;thellstrom@vmware.com&gt;
Reviewed-by: Steven Price &lt;steven.price@arm.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a new header for the two handful of users of the walk_page_range /
walk_page_vma interface instead of polluting all users of mm.h with it.

Link: https://lore.kernel.org/r/20190828141955.22210-2-hch@lst.de
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Thomas Hellstrom &lt;thellstrom@vmware.com&gt;
Reviewed-by: Steven Price &lt;steven.price@arm.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: thp: fix false negative of shmem vma's THP eligibility</title>
<updated>2019-07-19T00:08:06+00:00</updated>
<author>
<name>Yang Shi</name>
<email>yang.shi@linux.alibaba.com</email>
</author>
<published>2019-07-18T22:57:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c06306696f8368b08774e2a743dbc52d92a61693'/>
<id>c06306696f8368b08774e2a743dbc52d92a61693</id>
<content type='text'>
Commit 7635d9cbe832 ("mm, thp, proc: report THP eligibility for each
vma") introduced THPeligible bit for processes' smaps.  But, when
checking the eligibility for shmem vma, __transparent_hugepage_enabled()
is called to override the result from shmem_huge_enabled().  It may
result in the anonymous vma's THP flag override shmem's.  For example,
running a simple test which create THP for shmem, but with anonymous THP
disabled, when reading the process's smaps, it may show:

  7fc92ec00000-7fc92f000000 rw-s 00000000 00:14 27764 /dev/shm/test
  Size:               4096 kB
  ...
  [snip]
  ...
  ShmemPmdMapped:     4096 kB
  ...
  [snip]
  ...
  THPeligible:    0

And, /proc/meminfo does show THP allocated and PMD mapped too:

  ShmemHugePages:     4096 kB
  ShmemPmdMapped:     4096 kB

This doesn't make too much sense.  The shmem objects should be treated
separately from anonymous THP.  Calling shmem_huge_enabled() with
checking MMF_DISABLE_THP sounds good enough.  And, we could skip stack
and dax vma check since we already checked if the vma is shmem already.

Also check if vma is suitable for THP by calling
transhuge_vma_suitable().

And minor fix to smaps output format and documentation.

Link: http://lkml.kernel.org/r/1560401041-32207-3-git-send-email-yang.shi@linux.alibaba.com
Fixes: 7635d9cbe832 ("mm, thp, proc: report THP eligibility for each vma")
Signed-off-by: Yang Shi &lt;yang.shi@linux.alibaba.com&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 7635d9cbe832 ("mm, thp, proc: report THP eligibility for each
vma") introduced THPeligible bit for processes' smaps.  But, when
checking the eligibility for shmem vma, __transparent_hugepage_enabled()
is called to override the result from shmem_huge_enabled().  It may
result in the anonymous vma's THP flag override shmem's.  For example,
running a simple test which create THP for shmem, but with anonymous THP
disabled, when reading the process's smaps, it may show:

  7fc92ec00000-7fc92f000000 rw-s 00000000 00:14 27764 /dev/shm/test
  Size:               4096 kB
  ...
  [snip]
  ...
  ShmemPmdMapped:     4096 kB
  ...
  [snip]
  ...
  THPeligible:    0

And, /proc/meminfo does show THP allocated and PMD mapped too:

  ShmemHugePages:     4096 kB
  ShmemPmdMapped:     4096 kB

This doesn't make too much sense.  The shmem objects should be treated
separately from anonymous THP.  Calling shmem_huge_enabled() with
checking MMF_DISABLE_THP sounds good enough.  And, we could skip stack
and dax vma check since we already checked if the vma is shmem already.

Also check if vma is suitable for THP by calling
transhuge_vma_suitable().

And minor fix to smaps output format and documentation.

Link: http://lkml.kernel.org/r/1560401041-32207-3-git-send-email-yang.shi@linux.alibaba.com
Fixes: 7635d9cbe832 ("mm, thp, proc: report THP eligibility for each vma")
Signed-off-by: Yang Shi &lt;yang.shi@linux.alibaba.com&gt;
Acked-by: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@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;
</pre>
</div>
</content>
</entry>
</feed>
