Commits · af1c31acc85325aec2bcc5941fb7a02e19143503 · Kirill Smelkov / linux

06 Nov, 2021 40 commits

mm/vmstat: annotate data race for zone->free_area[order].nr_free · af1c31ac

Liu Shixin authored Nov 05, 2021

KCSAN reports a data-race on v5.10 which also exists on mainline:

  BUG: KCSAN: data-race in extfrag_for_order+0x33/0x2d0

  race at unknown origin, with read to 0xffff9ee9bfffab48 of 8 bytes by task 34 on cpu 1:
   extfrag_for_order+0x33/0x2d0
   kcompactd+0x5f0/0xce0
   kthread+0x1f9/0x220
   ret_from_fork+0x22/0x30

  Reported by Kernel Concurrency Sanitizer on:
  CPU: 1 PID: 34 Comm: kcompactd0 Not tainted 5.10.0+ #2
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014

Access to zone->free_area[order].nr_free in extfrag_for_order() and
frag_show_print() is lockless.  That's intentional and the stats are a
rough estimate anyway.  Annotate them with data_race().

[liushixin2@huawei.com: add comments]
  Link: https://lkml.kernel.org/r/20210918084655.2696522-1-liushixin2@huawei.com

Link: https://lkml.kernel.org/r/20210908015606.3999871-1-liushixin2@huawei.comSigned-off-by: Liu Shixin <liushixin2@huawei.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

af1c31ac

selftests: vm: add KSM huge pages merging time test · 32525489

Pedro Demarchi Gomes authored Nov 05, 2021

Add test case of KSM merging time using mostly huge pages

Link: https://lkml.kernel.org/r/20211013044045.360251-1-pedrodemargomes@gmail.comSigned-off-by: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

32525489

selftest/vm: fix ksm selftest to run with different NUMA topologies · e3820ab2

Aneesh Kumar K.V authored Nov 05, 2021

Platforms can have non-contiguous NUMA nodes like below

   #numactl  -H
  available: 2 nodes (0,8)
  .....
  node distances:
  node   0   8
    0:  10  40
    8:  40  10

   #numactl  -H
  available: 1 nodes (1)
  ....
  node distances:
  node   1
    1:  10

Hence update the test to not assume the presence of Node 0 and 1 and
also use numa_num_configured_nodes() instead of numa_max_node for
finding whether to skip the test.

Link: https://lkml.kernel.org/r/20210914141414.350759-1-aneesh.kumar@linux.ibm.com
Fixes: 82e717ad ("selftests: vm: add KSM merging across nodes test")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

e3820ab2

mm: nommu: kill arch_get_unmapped_area() · 916caa12

Kefeng Wang authored Nov 05, 2021

When nommu, the arch_get_unmapped_area() will not be called, just kill
it.

Link: https://lkml.kernel.org/r/20210910061906.36299-1-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

916caa12

mm/readahead.c: fix incorrect comments for get_init_ra_size · fb25a77d

Lin Feng authored Nov 05, 2021

In fact, formated values returned by get_init_ra_size are not that
intuitive. This patch make the comments reflect its truth.

Link: https://lkml.kernel.org/r/20211019104812.135602-1-linf@wangsu.comSigned-off-by: Lin Feng <linf@wangsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fb25a77d

mm, thp: fix incorrect unmap behavior for private pages · 8468e937

Rongwei Wang authored Nov 05, 2021

When truncating pagecache on file THP, the private pages of a process
should not be unmapped mapping.  This incorrect behavior on a dynamic
shared libraries which will cause related processes to happen core dump.

A simple test for a DSO (Prerequisite is the DSO mapped in file THP):

    int main(int argc, char *argv[])
    {
	int fd;

	fd = open(argv[1], O_WRONLY);
	if (fd < 0) {
		perror("open");
	}

	close(fd);
	return 0;
    }

The test only to open a target DSO, and do nothing.  But this operation
will lead one or more process to happen core dump.  This patch mainly to
fix this bug.

Link: https://lkml.kernel.org/r/20211025092134.18562-3-rongwei.wang@linux.alibaba.com
Fixes: eb6ecbed ("mm, thp: relax the VM_DENYWRITE constraint on file-backed THPs")
Signed-off-by: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Tested-by: Xu Yu <xuyu@linux.alibaba.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Collin Fijalkovich <cfijalkovich@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

8468e937

mm, thp: lock filemap when truncating page cache · 55fc0d91

Rongwei Wang authored Nov 05, 2021

Patch series "fix two bugs for file THP".

This patch (of 2):

Transparent huge page has supported read-only non-shmem files.  The
file- backed THP is collapsed by khugepaged and truncated when written
(for shared libraries).

However, there is a race when multiple writers truncate the same page
cache concurrently.

In that case, subpage(s) of file THP can be revealed by find_get_entry
in truncate_inode_pages_range, which will trigger PageTail BUG_ON in
truncate_inode_page, as follows:

    page:000000009e420ff2 refcount:1 mapcount:0 mapping:0000000000000000 index:0x7ff pfn:0x50c3ff
    head:0000000075ff816d order:9 compound_mapcount:0 compound_pincount:0
    flags: 0x37fffe0000010815(locked|uptodate|lru|arch_1|head)
    raw: 37fffe0000000000 fffffe0013108001 dead000000000122 dead000000000400
    raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
    head: 37fffe0000010815 fffffe001066bd48 ffff000404183c20 0000000000000000
    head: 0000000000000600 0000000000000000 00000001ffffffff ffff000c0345a000
    page dumped because: VM_BUG_ON_PAGE(PageTail(page))
    ------------[ cut here ]------------
    kernel BUG at mm/truncate.c:213!
    Internal error: Oops - BUG: 0 [#1] SMP
    Modules linked in: xfs(E) libcrc32c(E) rfkill(E) ...
    CPU: 14 PID: 11394 Comm: check_madvise_d Kdump: ...
    Hardware name: ECS, BIOS 0.0.0 02/06/2015
    pstate: 60400005 (nZCv daif +PAN -UAO -TCO BTYPE=--)
    Call trace:
     truncate_inode_page+0x64/0x70
     truncate_inode_pages_range+0x550/0x7e4
     truncate_pagecache+0x58/0x80
     do_dentry_open+0x1e4/0x3c0
     vfs_open+0x38/0x44
     do_open+0x1f0/0x310
     path_openat+0x114/0x1dc
     do_filp_open+0x84/0x134
     do_sys_openat2+0xbc/0x164
     __arm64_sys_openat+0x74/0xc0
     el0_svc_common.constprop.0+0x88/0x220
     do_el0_svc+0x30/0xa0
     el0_svc+0x20/0x30
     el0_sync_handler+0x1a4/0x1b0
     el0_sync+0x180/0x1c0
    Code: aa0103e0 900061e1 910ec021 9400d300 (d4210000)

This patch mainly to lock filemap when one enter truncate_pagecache(),
avoiding truncating the same page cache concurrently.

Link: https://lkml.kernel.org/r/20211025092134.18562-1-rongwei.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/20211025092134.18562-2-rongwei.wang@linux.alibaba.com
Fixes: eb6ecbed ("mm, thp: relax the VM_DENYWRITE constraint on file-backed THPs")
Signed-off-by: Xu Yu <xuyu@linux.alibaba.com>
Signed-off-by: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Song Liu <song@kernel.org>
Cc: Collin Fijalkovich <cfijalkovich@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

55fc0d91

selftests/vm/transhuge-stress: fix ram size thinko · 39cad887

George G. Davis authored Nov 05, 2021

When executing transhuge-stress with an argument to specify the virtual
memory size for testing, the ram size is reported as 0, e.g.

  transhuge-stress 384
  thp-mmap: allocate 192 transhuge pages, using 384 MiB virtual memory and 0 MiB of ram
  thp-mmap: 0.184 s/loop, 0.957 ms/page,   2090.265 MiB/s  192 succeed,    0 failed

This appears to be due to a thinko in commit 0085d61f
("selftests/vm/transhuge-stress: stress test for memory compaction"),
where, at a guess, the intent was to base "xyz MiB of ram" on `ram`
size.

Here are results after using `ram` size:

  thp-mmap: allocate 192 transhuge pages, using 384 MiB virtual memory and 14 MiB of ram

Link: https://lkml.kernel.org/r/20210825135843.29052-1-george_davis@mentor.com
Fixes: 0085d61f ("selftests/vm/transhuge-stress: stress test for memory compaction")
Signed-off-by: George G. Davis <davis.george@siemens.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Eugeniu Rosca <erosca@de.adit-jv.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

39cad887

mm: migrate: make demotion knob depend on migration · 20f9ba4f

Yang Shi authored Nov 05, 2021

The memory demotion needs to call migrate_pages() to do the jobs. And
it is controlled by a knob, however, the knob doesn't depend on
CONFIG_MIGRATION. The knob could be truned on even though MIGRATION is
disabled, this will not cause any crash since migrate_pages() would just
return -ENOSYS. But it is definitely not optimal to go through demotion
path then retry regular swap every time.

And it doesn't make too much sense to have the knob visible to the users
when !MIGRATION. Move the related code from mempolicy.[h|c] to
migrate.[h|c].

Link: https://lkml.kernel.org/r/20211015005559.246709-1-shy828301@gmail.comSigned-off-by: Yang Shi <shy828301@gmail.com>
Acked-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

20f9ba4f

mm/migrate: de-duplicate migrate_reason strings · 8eb42bea

John Hubbard authored Nov 05, 2021

In order to remove the need to manually keep three different files in
synch, provide a common definition of the mapping between enum
migrate_reason, and the associated strings for each enum item.

1. Use the tracing system's mapping of enums to strings, by redefining
and reusing the MIGRATE_REASON and supporting macros, and using that
to populate the string array in mm/debug.c.

2. Move enum migrate_reason to migrate_mode.h. This is not strictly
necessary for this patch, but migrate mode and migrate reason go
together, so this will slightly clarify things.

Link: https://lkml.kernel.org/r/20210922041755.141817-2-jhubbard@nvidia.comSigned-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Weizhao Ouyang <o451686892@gmail.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

8eb42bea

hugetlbfs: extend the definition of hugepages parameter to support node allocation · b5389086

Zhenguo Yao authored Nov 05, 2021

We can specify the number of hugepages to allocate at boot.  But the
hugepages is balanced in all nodes at present.  In some scenarios, we
only need hugepages in one node.  For example: DPDK needs hugepages
which are in the same node as NIC.

If DPDK needs four hugepages of 1G size in node1 and system has 16 numa
nodes we must reserve 64 hugepages on the kernel cmdline.  But only four
hugepages are used.  The others should be free after boot.  If the
system memory is low(for example: 64G), it will be an impossible task.

So extend the hugepages parameter to support specifying hugepages on a
specific node.  For example add following parameter:

  hugepagesz=1G hugepages=0:1,1:3

It will allocate 1 hugepage in node0 and 3 hugepages in node1.

Link: https://lkml.kernel.org/r/20211005054729.86457-1-yaozhenguo1@gmail.comSigned-off-by: Zhenguo Yao <yaozhenguo1@gmail.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Zhenguo Yao <yaozhenguo1@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

b5389086

mm: mark the OOM reaper thread as freezable · 3723929e

Sultan Alsawaf authored Nov 05, 2021

The OOM reaper alters user address space which might theoretically alter
the snapshot if reaping is allowed to happen after the freezer quiescent
state.  To this end, the reaper kthread uses wait_event_freezable()
while waiting for any work so that it cannot run while the system
freezes.

However, the current implementation doesn't respect the freezer because
all kernel threads are created with the PF_NOFREEZE flag, so they are
automatically excluded from freezing operations.  This means that the
OOM reaper can race with system snapshotting if it has work to do while
the system is being frozen.

Fix this by adding a set_freezable() call which will clear the
PF_NOFREEZE flag and thus make the OOM reaper visible to the freezer.

Please note that the OOM reaper altering the snapshot this way is mostly
a theoretical concern and has not been observed in practice.

Link: https://lkml.kernel.org/r/20210921165758.6154-1-sultan@kerneltoast.com
Link: https://lkml.kernel.org/r/20210918233920.9174-1-sultan@kerneltoast.com
Fixes: aac45363 ("mm, oom: introduce oom reaper")
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3723929e

memblock: use memblock_free for freeing virtual pointers · 4421cca0

Mike Rapoport authored Nov 05, 2021

Rename memblock_free_ptr() to memblock_free() and use memblock_free()
when freeing a virtual pointer so that memblock_free() will be a
counterpart of memblock_alloc()

The callers are updated with the below semantic patch and manual
addition of (void *) casting to pointers that are represented by
unsigned long variables.

    @@
    identifier vaddr;
    expression size;
    @@
    (
    - memblock_phys_free(__pa(vaddr), size);
    + memblock_free(vaddr, size);
    |
    - memblock_free_ptr(vaddr, size);
    + memblock_free(vaddr, size);
    )

[sfr@canb.auug.org.au: fixup]
  Link: https://lkml.kernel.org/r/20211018192940.3d1d532f@canb.auug.org.au

Link: https://lkml.kernel.org/r/20210930185031.18648-7-rppt@kernel.orgSigned-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4421cca0

memblock: rename memblock_free to memblock_phys_free · 3ecc6834

Mike Rapoport authored Nov 05, 2021

Since memblock_free() operates on a physical range, make its name
reflect it and rename it to memblock_phys_free(), so it will be a
logical counterpart to memblock_phys_alloc().

The callers are updated with the below semantic patch:

    @@
    expression addr;
    expression size;
    @@
    - memblock_free(addr, size);
    + memblock_phys_free(addr, size);

Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.orgSigned-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3ecc6834

memblock: stop aliasing __memblock_free_late with memblock_free_late · 621d9739

Mike Rapoport authored Nov 05, 2021

memblock_free_late() is a NOP wrapper for __memblock_free_late(), there
is no point to keep this indirection.

Drop the wrapper and rename __memblock_free_late() to
memblock_free_late().

Link: https://lkml.kernel.org/r/20210930185031.18648-5-rppt@kernel.orgSigned-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

621d9739

memblock: drop memblock_free_early_nid() and memblock_free_early() · fa277171

Mike Rapoport authored Nov 05, 2021

memblock_free_early_nid() is unused and memblock_free_early() is an
alias for memblock_free().

Replace calls to memblock_free_early() with calls to memblock_free() and
remove memblock_free_early() and memblock_free_early_nid().

Link: https://lkml.kernel.org/r/20210930185031.18648-4-rppt@kernel.orgSigned-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fa277171

xen/x86: free_p2m_page: use memblock_free_ptr() to free a virtual pointer · c486514d

Mike Rapoport authored Nov 05, 2021

free_p2m_page() wrongly passes a virtual pointer to memblock_free() that
treats it as a physical address.

Call memblock_free_ptr() instead that gets a virtual address to free the
memory.

Link: https://lkml.kernel.org/r/20210930185031.18648-3-rppt@kernel.orgSigned-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

c486514d

arch_numa: simplify numa_distance allocation · 5787ea5b

Mike Rapoport authored Nov 05, 2021

Patch series "memblock: cleanup memblock_free interface", v2.

This is the fix for memblock freeing APIs mismatch [1].

The first patch is a cleanup of numa_distance allocation in arch_numa
I've spotted during the conversion.  The second patch is a fix for Xen
memory freeing on some of the error paths.

[1] https://lore.kernel.org/all/CAHk-=wj9k4LZTz+svCxLYs5Y1=+yKrbAUArH1+ghyG3OLd8VVg@mail.gmail.com

This patch (of 6):

Memory allocation of numa_distance uses memblock_phys_alloc_range()
without actual range limits, converts the returned physical address to
virtual and then only uses the virtual address for further
initialization.

Simplify this by replacing memblock_phys_alloc_range() with
memblock_alloc().

Link: https://lkml.kernel.org/r/20210930185031.18648-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20210930185031.18648-2-rppt@kernel.orgSigned-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5787ea5b

tools/vm/page-types.c: print file offset in hexadecimal · 41d4613b

Naoya Horiguchi authored Nov 05, 2021

In page list mode (with -l and -L option), virtual address and physical
address are printed in hexadecimal, but file offset is not, which is
confusing, so let's align it.

Link: https://lkml.kernel.org/r/20211004061325.1525902-4-naoya.horiguchi@linux.devSigned-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Bin Wang <wangbin224@huawei.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

41d4613b

tools/vm/page-types.c: move show_file() to summary output · b76901db

Naoya Horiguchi authored Nov 05, 2021

Currently file info from show_file() is printed out within page list
like below, but this is inconvenient a little to utilize the page list
from other scripts (maybe needs additional filtering).

$ ./page-types -f page-types.c -l
foffset offset len flags
page-types.c Inode: 15108680 Size: 30953 (8 pages)
Modify: Sat Oct 2 23:11:20 2021 (2399 seconds ago)
Access: Sat Oct 2 23:11:28 2021 (2391 seconds ago)
0 d9f59e 1 ___U_lA____________________________________
1 1031eb5 1 __RU_l_____________________________________
2 13bf717 1 __RU_l_____________________________________
3 13ac333 1 ___U_lA____________________________________
4 d9f59f 1 __RU_l_____________________________________
5 183fd49 1 ___U_lA____________________________________
6 13cbf69 1 ___U_lA____________________________________
7 d9ef05 1 ___U_lA____________________________________

flags page-count MB symbolic-flags long-symbolic-flags
0x000000000000002c 3 0 __RU_l_____________________________________ referenced,uptodate,lru
0x0000000000000068 5 0 ___U_lA____________________________________ uptodate,lru,active
total 8 0

With this patch file info is printed out in summary part like below:

$ ./page-types -f page-types.c -l
foffset offset len flags
0 d9f59e 1 ___U_lA_____________________________________
1 1031eb5 1 __RU_l______________________________________
2 13bf717 1 __RU_l______________________________________
3 13ac333 1 ___U_lA_____________________________________
4 d9f59f 1 __RU_l______________________________________
5 183fd49 1 ___U_lA_____________________________________
6 13cbf69 1 ___U_lA_____________________________________

page-types.c Inode: 15108680 Size: 30953 (8 pages)
Modify: Sat Oct 2 23:11:20 2021 (2435 seconds ago)
Access: Sat Oct 2 23:11:28 2021 (2427 seconds ago)

flags page-count MB symbolic-flags long-symbolic-flags
0x000000000000002c 3 0 __RU_l______________________________________ referenced,uptodate,lru
0x0000000000000068 4 0 ___U_lA_____________________________________ uptodate,lru,active
total 7 0

Link: https://lkml.kernel.org/r/20211004061325.1525902-3-naoya.horiguchi@linux.devSigned-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Bin Wang <wangbin224@huawei.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

b76901db

tools/vm/page-types.c: make walk_file() aware of address range option · a62f5ecb

Naoya Horiguchi authored Nov 05, 2021

Patch series "tools/vm/page-types.c: a few improvements".

This patchset adds some improvements on tools/vm/page-types.c.  Patch
1/3 makes -a option (specify address range) work with -f (file cache
mode).  Patch 2/3 and 3/3 are to fix minor formatting issues of this
tool.  These would make life a little easier for the users of this tool.

Please see individual patches for more details about specific issues.

This patch (of 3):

-a|--addr option is used to limit the range of address to be scanned for
page status.  It works now for physical address space (dafult mode) or for
virtual address space (with -p option), but not for file address space
(with -f option).  So make walk_file() aware of -a option.

Link: https://lkml.kernel.org/r/20211004061325.1525902-1-naoya.horiguchi@linux.dev
Link: https://lkml.kernel.org/r/20211004061325.1525902-2-naoya.horiguchi@linux.devSigned-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Bin Wang <wangbin224@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

a62f5ecb

tools/vm/page_owner_sort.c: count and sort by mem · f7df2b1c

Zhenliang Wei authored Nov 05, 2021

When viewing page owner information, we may be more concerned about the
total memory rather than the times of stack appears.  Therefore, the
following adjustments are made:

1. Added the statistics on the total number of pages.

2. Added the optional parameter "-m" to configure the program to sort by
   memory (total pages).

The general output of page_owner is as follows:

	Page allocated via order XXX, ...
	PFN XXX ...
	 // Detailed stack

	Page allocated via order XXX, ...
	PFN XXX ...
	 // Detailed stack

The original page_owner_sort ignores PFN rows, puts the remaining rows
in buf, counts the times of buf, and finally sorts them according to the
times.  General output:

	XXX times:
	Page allocated via order XXX, ...
	 // Detailed stack

Now, we use regexp to extract the page order value from the buf, and
count the total pages for the buf.  General output:

	XXX times, XXX pages:
	Page allocated via order XXX, ...
	 // Detailed stack

By default, it is still sorted by the times of buf; If you want to sort
by the pages nums of buf, use the new -m parameter.

Link: https://lkml.kernel.org/r/1631678242-41033-1-git-send-email-weizhenliang@huawei.comSigned-off-by: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Tang Bin <tangbin@cmss.chinamobile.com>
Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f7df2b1c

mm/vmpressure: fix data-race with memcg->socket_pressure · 7e6ec49c

Yuanzheng Song authored Nov 05, 2021

When reading memcg->socket_pressure in mem_cgroup_under_socket_pressure()
and writing memcg->socket_pressure in vmpressure() at the same time, the
following data-race occurs:

  BUG: KCSAN: data-race in __sk_mem_reduce_allocated / vmpressure

  write to 0xffff8881286f4938 of 8 bytes by task 24550 on cpu 3:
   vmpressure+0x218/0x230 mm/vmpressure.c:307
   shrink_node_memcgs+0x2b9/0x410 mm/vmscan.c:2658
   shrink_node+0x9d2/0x11d0 mm/vmscan.c:2769
   shrink_zones+0x29f/0x470 mm/vmscan.c:2972
   do_try_to_free_pages+0x193/0x6e0 mm/vmscan.c:3027
   try_to_free_mem_cgroup_pages+0x1c0/0x3f0 mm/vmscan.c:3345
   reclaim_high mm/memcontrol.c:2440 [inline]
   mem_cgroup_handle_over_high+0x18b/0x4d0 mm/memcontrol.c:2624
   tracehook_notify_resume include/linux/tracehook.h:197 [inline]
   exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
   exit_to_user_mode_prepare+0x110/0x170 kernel/entry/common.c:191
   syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
   ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:289

  read to 0xffff8881286f4938 of 8 bytes by interrupt on cpu 1:
   mem_cgroup_under_socket_pressure include/linux/memcontrol.h:1483 [inline]
   sk_under_memory_pressure include/net/sock.h:1314 [inline]
   __sk_mem_reduce_allocated+0x1d2/0x270 net/core/sock.c:2696
   __sk_mem_reclaim+0x44/0x50 net/core/sock.c:2711
   sk_mem_reclaim include/net/sock.h:1490 [inline]
   ......
   net_rx_action+0x17a/0x480 net/core/dev.c:6864
   __do_softirq+0x12c/0x2af kernel/softirq.c:298
   run_ksoftirqd+0x13/0x20 kernel/softirq.c:653
   smpboot_thread_fn+0x33f/0x510 kernel/smpboot.c:165
   kthread+0x1fc/0x220 kernel/kthread.c:292
   ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Fix it by using READ_ONCE() and WRITE_ONCE() to read and write
memcg->socket_pressure.

Link: https://lkml.kernel.org/r/20211025082843.671690-1-songyuanzheng@huawei.comSigned-off-by: Yuanzheng Song <songyuanzheng@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Alex Shi <alexs@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>