This implements new DAMON_RECLAIM parameters for statistics reporting.
Those can be used for understanding how DAMON_RECLAIM is working, and
for tuning the other parameters.
Link: https://lkml.kernel.org/r/20211210150016.35349-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the time/space quotas of a given DAMON-based operation scheme is too
small, the scheme could show unexpectedly slow progress. However, there
is no good way to notice the case in runtime. This commit extends the
DAMOS stat to provide how many times the quota limits exceeded so that
the users can easily notice the case and tune the scheme.
Link: https://lkml.kernel.org/r/20211210150016.35349-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/damon/schemes: Extend stats for better online analysis and tuning".
To help online access pattern analysis and tuning of DAMON-based
Operation Schemes (DAMOS), DAMOS provides simple statistics for each
scheme. Introduction of DAMOS time/space quota further made the tuning
easier by making the risk management easier. However, that also made
understanding of the working schemes a little bit more difficult.
For an example, progress of a given scheme can now be throttled by not
only the aggressiveness of the target access pattern, but also the
time/space quotas. So, when a scheme is showing unexpectedly slow
progress, it's difficult to know by what the progress of the scheme is
throttled, with currently provided statistics.
This patchset extends the statistics to contain some metrics that can be
helpful for such online schemes analysis and tuning (patches 1-2),
exports those to users (patches 3 and 5), and add documents (patches 4
and 6).
This patch (of 6):
DAMON-based operation schemes (DAMOS) stats provide only the number and
the amount of regions that the action of the scheme has tried to be
applied. Because the action could be failed for some reasons, the
currently provided information is sometimes not useful or convenient
enough for schemes profiling and tuning. To improve this situation,
this commit extends the DAMOS stats to provide the number and the amount
of regions that the action has successfully applied.
Link: https://lkml.kernel.org/r/20211210150016.35349-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211210150016.35349-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Due to a mistake in patches reordering, a comment for a future feature
called 'arbitrary monitoring target support'[1], which is still under
development, has added. Because it only introduces confusion and we
don't have a plan to post the patches soon, this commit removes the
mistakenly added part.
[1] https://lore.kernel.org/linux-mm/20201215115448.25633-3-sjpark@amazon.com/
Link: https://lkml.kernel.org/r/20211209131806.19317-7-sj@kernel.org
Fixes: 1f366e421c ("mm/damon/core: implement DAMON-based Operation Schemes (DAMOS)")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The DAMON debugfs usage document is missing descriptions for
'kdamond_pid', 'mk_contexts', and 'rm_contexts' debugfs files. This
commit adds those.
Link: https://lkml.kernel.org/r/20211209131806.19317-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To get detailed monitoring results from the user space, users need to
use the damon_aggregated tracepoint. This commit adds a brief mention
of it at the beginning of the usage document.
Link: https://lkml.kernel.org/r/20211209131806.19317-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
DAMON usage document mentions DAMON user space tool and programming
interface twice. This commit integrates those and remove unnecessary
part.
Link: https://lkml.kernel.org/r/20211209131806.19317-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
DAMOS features including time/space quota limits and watermarks are not
described in the DAMON debugfs interface document. This commit updates
the document for the features.
Link: https://lkml.kernel.org/r/20211209131806.19317-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
damon_rand() cannot be implemented as a macro.
Example:
damon_rand(a++, b);
The value of 'a' will be incremented twice, This is obviously
unreasonable, So there fix it.
Link: https://lkml.kernel.org/r/110ffcd4e420c86c42b41ce2bc9f0fe6a4f32cd3.1638795127.git.xhao@linux.alibaba.com
Fixes: b9a6ac4e4e ("mm/damon: adaptively adjust regions")
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
damon_rand() is called in three files:damon/core.c, damon/ paddr.c,
damon/vaddr.c, i think there is no need to redefine this twice, So move
it to damon.h will be a good choice.
Link: https://lkml.kernel.org/r/20211202075859.51341-1-xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove 'swap_ranges()' and replace it with the macro 'swap()' defined in
'include/linux/minmax.h' to simplify code and improve efficiency
Link: https://lkml.kernel.org/r/20211111115355.2808-1-hanyihao@vivo.com
Signed-off-by: Yihao Han <hanyihao@vivo.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In damon.h some func definitions about VA & PA can only be used in its
own file, so there no need to define in the header file, and the header
file will look cleaner.
If other files later need these functions, the prototypes can be added
to damon.h at that time.
[sj@kernel.org: remove unnecessary function prototype position changes]
Link: https://lkml.kernel.org/r/20211118114827.20052-1-sj@kernel.org
Link: https://lkml.kernel.org/r/45fd5b3ef6cce8e28dbc1c92f9dc845ccfc949d7.1636989871.git.xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In kernel, we can use abs(a - b) to get the absolute value, So there is no
need to redefine a new one.
Link: https://lkml.kernel.org/r/b24e7b82d9efa90daf150d62dea171e19390ad0b.1636989871.git.xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In Damon, we can get age information by analyzing the nr_access change,
But short time sampling is not effective, we have to obtain enough data
for analysis through long time trace, this also means that we need to
consume more cpu resources and storage space.
Now the region add a new 'age' variable, we only need to get the change of
age value through a little time trace, for example, age has been
increasing to 141, but nr_access shows a value of 0 at the same time,
Through this,we can conclude that the region has a very low nr_access
value for a long time.
Link: https://lkml.kernel.org/r/b9def1262af95e0dc1d0caea447886434db01161.1636989871.git.xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/damon: Do some small changes", v4.
This patch (of 4):
In damon/paddr.c file, two functions names start with underscore,
static void __damon_pa_prepare_access_check(struct damon_ctx *ctx,
struct damon_region *r)
static void __damon_pa_prepare_access_check(struct damon_ctx *ctx,
struct damon_region *r)
In damon/vaddr.c file, there are also two functions with the same function,
static void damon_va_prepare_access_check(struct damon_ctx *ctx,
struct mm_struct *mm, struct damon_region *r)
static void damon_va_check_access(struct damon_ctx *ctx,
struct mm_struct *mm, struct damon_region *r)
It makes sense to keep consistent, and it is not easy to be confused with
the function that call them.
Link: https://lkml.kernel.org/r/cover.1636989871.git.xhao@linux.alibaba.com
Link: https://lkml.kernel.org/r/529054aed932a42b9c09fc9977ad4574b9e7b0bd.1636989871.git.xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hmm_range_fault() can be used instead of get_user_pages() for devices
which allow faulting however unlike get_user_pages() it will return an
error when used on a VM_MIXEDMAP range.
To make hmm_range_fault() more closely match get_user_pages() remove
this restriction. This requires dealing with the !ARCH_HAS_PTE_SPECIAL
case in hmm_vma_handle_pte(). Rather than replicating the logic of
vm_normal_page() call it directly and do a check for the zero pfn
similar to what get_user_pages() currently does.
Also add a test to hmm selftest to verify functionality.
Link: https://lkml.kernel.org/r/20211104012001.2555676-1-apopple@nvidia.com
Fixes: da4c3c735e ("mm/hmm/mirror: helper to snapshot CPU page table")
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"page_idle_ops" as a global var, but its scope of use within this
document. So it should be static.
"page_ext_ops" is a var used in the kernel initial phase. And other
functions are aslo used in the kernel initial phase. So they should be
__init or __initdata to reclaim memory.
Link: https://lkml.kernel.org/r/20211217095023.67293-1-liuting.0x7c00@bytedance.com
Signed-off-by: Ting Liu <liuting.0x7c00@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The list of pools_head is no longer needed because the caller has been
deleted in commit 479305fd71 ("zpool: remove zpool_evict()").
Link: https://lkml.kernel.org/r/20211215163727.GA17196@pc
Signed-off-by: Zhaoyu Liu <zackary.liu.pro@gmail.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In theory, the following race is possible for batched TLB flushing.
CPU0 CPU1
---- ----
shrink_page_list()
unmap
zap_pte_range()
flush_tlb_batched_pending()
flush_tlb_mm()
try_to_unmap()
set_tlb_ubc_flush_pending()
mm->tlb_flush_batched = true
mm->tlb_flush_batched = false
After the TLB is flushed on CPU1 via flush_tlb_mm() and before
mm->tlb_flush_batched is set to false, some PTE is unmapped on CPU0 and
the TLB flushing is pended. Then the pended TLB flushing will be lost.
Although both set_tlb_ubc_flush_pending() and
flush_tlb_batched_pending() are called with PTL locked, different PTL
instances may be used.
Because the race window is really small, and the lost TLB flushing will
cause problem only if a TLB entry is inserted before the unmapping in
the race window, the race is only theoretical. But the fix is simple
and cheap too.
Syzbot has reported this too as follows:
==================================================================
BUG: KCSAN: data-race in flush_tlb_batched_pending / try_to_unmap_one
write to 0xffff8881072cfbbc of 1 bytes by task 17406 on cpu 1:
flush_tlb_batched_pending+0x5f/0x80 mm/rmap.c:691
madvise_free_pte_range+0xee/0x7d0 mm/madvise.c:594
walk_pmd_range mm/pagewalk.c:128 [inline]
walk_pud_range mm/pagewalk.c:205 [inline]
walk_p4d_range mm/pagewalk.c:240 [inline]
walk_pgd_range mm/pagewalk.c:277 [inline]
__walk_page_range+0x981/0x1160 mm/pagewalk.c:379
walk_page_range+0x131/0x300 mm/pagewalk.c:475
madvise_free_single_vma mm/madvise.c:734 [inline]
madvise_dontneed_free mm/madvise.c:822 [inline]
madvise_vma mm/madvise.c:996 [inline]
do_madvise+0xe4a/0x1140 mm/madvise.c:1202
__do_sys_madvise mm/madvise.c:1228 [inline]
__se_sys_madvise mm/madvise.c:1226 [inline]
__x64_sys_madvise+0x5d/0x70 mm/madvise.c:1226
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
write to 0xffff8881072cfbbc of 1 bytes by task 71 on cpu 0:
set_tlb_ubc_flush_pending mm/rmap.c:636 [inline]
try_to_unmap_one+0x60e/0x1220 mm/rmap.c:1515
rmap_walk_anon+0x2fb/0x470 mm/rmap.c:2301
try_to_unmap+0xec/0x110
shrink_page_list+0xe91/0x2620 mm/vmscan.c:1719
shrink_inactive_list+0x3fb/0x730 mm/vmscan.c:2394
shrink_list mm/vmscan.c:2621 [inline]
shrink_lruvec+0x3c9/0x710 mm/vmscan.c:2940
shrink_node_memcgs+0x23e/0x410 mm/vmscan.c:3129
shrink_node+0x8f6/0x1190 mm/vmscan.c:3252
kswapd_shrink_node mm/vmscan.c:4022 [inline]
balance_pgdat+0x702/0xd30 mm/vmscan.c:4213
kswapd+0x200/0x340 mm/vmscan.c:4473
kthread+0x2c7/0x2e0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30
value changed: 0x01 -> 0x00
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 71 Comm: kswapd0 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
[akpm@linux-foundation.org: tweak comments]
Link: https://lkml.kernel.org/r/20211201021104.126469-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reported-by: syzbot+aa5bebed695edaccf0df@syzkaller.appspotmail.com
Cc: Nadav Amit <namit@vmware.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Similar to slab memory allocator, for each accounted percpu object there
is an extra space which is used to store obj_cgroup membership. Charge
it too.
[akpm@linux-foundation.org: fix layout]
Link: https://lkml.kernel.org/r/20211126040606.97836-1-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After recent soft-offline rework, error pages can be taken off from
buddy allocator, but the existing unpoison_memory() does not properly
undo the operation. Moreover, due to the recent change on
__get_hwpoison_page(), get_page_unless_zero() is hardly called for
hwpoisoned pages. So __get_hwpoison_page() highly likely returns -EBUSY
(meaning to fail to grab page refcount) and unpoison just clears
PG_hwpoison without releasing a refcount. That does not lead to a
critical issue like kernel panic, but unpoisoned pages never get back to
buddy (leaked permanently), which is not good.
To (partially) fix this, we need to identify "taken off" pages from
other types of hwpoisoned pages. We can't use refcount or page flags
for this purpose, so a pseudo flag is defined by hacking ->private
field. Someone might think that put_page() is enough to cancel
taken-off pages, but the normal free path contains some operations not
suitable for the current purpose, and can fire VM_BUG_ON().
Note that unpoison_memory() is now supposed to be cancel hwpoison events
injected only by madvise() or
/sys/devices/system/memory/{hard,soft}_offline_page, not by MCE
injection, so please don't try to use unpoison when testing with MCE
injection.
[lkp@intel.com: report build failure for ARCH=i386]
Link: https://lkml.kernel.org/r/20211115084006.3728254-4-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Ding Hui <dinghui@sangfor.com.cn>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These action_page_types are no longer used, so remove them.
Link: https://lkml.kernel.org/r/20211115084006.3728254-3-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ding Hui <dinghui@sangfor.com.cn>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/hwpoison: fix unpoison_memory()", v4.
The main purpose of this series is to sync unpoison code to recent
changes around how hwpoison code takes page refcount. Unpoison should
work or simply fail (without crash) if impossible.
The recent works of keeping hwpoison pages in shmem pagecache introduce
a new state of hwpoisoned pages, but unpoison for such pages is not
supported yet with this series.
It seems that soft-offline and unpoison can be used as general purpose
page offline/online mechanism (not in the context of memory error). I
think that we need some additional works to realize it because currently
soft-offline and unpoison are assumed not to happen so frequently (print
out too many messages for aggressive usecases). But anyway this could
be another interesting next topic.
v1: https://lore.kernel.org/linux-mm/20210614021212.223326-1-nao.horiguchi@gmail.com/
v2: https://lore.kernel.org/linux-mm/20211025230503.2650970-1-naoya.horiguchi@linux.dev/
v3: https://lore.kernel.org/linux-mm/20211105055058.3152564-1-naoya.horiguchi@linux.dev/
This patch (of 3):
Originally mf_mutex is introduced to serialize multiple MCE events, but
it is not that useful to allow unpoison to run in parallel with
memory_failure() and soft offline. So apply mf_mutex to soft offline
and unpoison. The memory failure handler and soft offline handler get
simpler with this.
Link: https://lkml.kernel.org/r/20211115084006.3728254-1-naoya.horiguchi@linux.dev
Link: https://lkml.kernel.org/r/20211115084006.3728254-2-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ding Hui <dinghui@sangfor.com.cn>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When under the stress of swapping in/out with KSM enabled, there is a
low probability that kasan reports the BUG of use-after-free in
ksm_might_need_to_copy() when do swap in. The freed object is the
anon_vma got from page_anon_vma(page).
It is because a swapcache page associated with one anon_vma now needed
for another anon_vma, but the page's original vma was unmapped and the
anon_vma was freed. In this case the if condition below always return
false and then alloc a new page to copy. Swapin process then use the
new page and can continue to run well, so this is harmless actually.
} else if (anon_vma->root == vma->anon_vma->root &&
page->index == linear_page_index(vma, address)) {
This patch exchange the order of above two judgment statement to avoid
the kasan warning. Let cpu run "page->index == linear_page_index(vma,
address)" firstly and return false basically to skip the read of
anon_vma->root which may trigger the kasan use-after-free warning:
==================================================================
BUG: KASAN: use-after-free in ksm_might_need_to_copy+0x12e/0x5b0
Read of size 8 at addr ffff88be9977dbd0 by task khugepaged/694
CPU: 8 PID: 694 Comm: khugepaged Kdump: loaded Tainted: G OE - 4.18.0.x86_64
Hardware name: 1288H V5/BC11SPSC0, BIOS 7.93 01/14/2021
Call Trace:
dump_stack+0xf1/0x19b
print_address_description+0x70/0x360
kasan_report+0x1b2/0x330
ksm_might_need_to_copy+0x12e/0x5b0
do_swap_page+0x452/0xe70
__collapse_huge_page_swapin+0x24b/0x720
khugepaged_scan_pmd+0xcae/0x1ff0
khugepaged+0x8ee/0xd70
kthread+0x1a2/0x1d0
ret_from_fork+0x1f/0x40
Allocated by task 2306153:
kasan_kmalloc+0xa0/0xd0
kmem_cache_alloc+0xc0/0x1c0
anon_vma_clone+0xf7/0x380
anon_vma_fork+0xc0/0x390
copy_process+0x447b/0x4810
_do_fork+0x118/0x620
do_syscall_64+0x112/0x360
entry_SYSCALL_64_after_hwframe+0x65/0xca
Freed by task 2306242:
__kasan_slab_free+0x130/0x180
kmem_cache_free+0x78/0x1d0
unlink_anon_vmas+0x19c/0x4a0
free_pgtables+0x137/0x1b0
exit_mmap+0x133/0x320
mmput+0x15e/0x390
do_exit+0x8c5/0x1210
do_group_exit+0xb5/0x1b0
__x64_sys_exit_group+0x21/0x30
do_syscall_64+0x112/0x360
entry_SYSCALL_64_after_hwframe+0x65/0xca
The buggy address belongs to the object at ffff88be9977dba0
which belongs to the cache anon_vma_chain of size 64
The buggy address is located 48 bytes inside of
64-byte region [ffff88be9977dba0, ffff88be9977dbe0)
The buggy address belongs to the page:
page:ffffea00fa65df40 count:1 mapcount:0 mapping:ffff888107717800 index:0x0
flags: 0x17ffffc0000100(slab)
==================================================================
Link: https://lkml.kernel.org/r/20211202102940.1069634-1-sunnanyong@huawei.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The trace events hugepage_[invalidate|splitting], were added via the
commit 9e813308a5 ("powerpc/thp: Add tracepoints to track hugepage
invalidate"). Afterwards their call sites i.e
trace_hugepage_[invalidate|splitting] were just dropped off, leaving
these trace points unused.
Link: https://lkml.kernel.org/r/1641546351-15109-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable addr is being set and incremented in a for-loop but not
actually being used. It is redundant and so addr and also variable
start can be removed.
Link: https://lkml.kernel.org/r/20211221185729.609630-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now, node_demotion and next_demotion_node() are placed between
__unmap_and_move() and unmap_and_move(). This hurts code readability.
So move them near their users in the file. There's no functionality
change in this patch.
Link: https://lkml.kernel.org/r/20211206031227.3323097-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Wei Xu <weixugc@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have some machines with multiple memory types like below, which have
one fast (DRAM) memory node and two slow (persistent memory) memory
nodes. According to current node demotion policy, if node 0 fills up,
its memory should be migrated to node 1, when node 1 fills up, its
memory will be migrated to node 2: node 0 -> node 1 -> node 2 ->stop.
But this is not efficient and suitbale memory migration route for our
machine with multiple slow memory nodes. Since the distance between
node 0 to node 1 and node 0 to node 2 is equal, and memory migration
between slow memory nodes will increase persistent memory bandwidth
greatly, which will hurt the whole system's performance.
Thus for this case, we can treat the slow memory node 1 and node 2 as a
whole slow memory region, and we should migrate memory from node 0 to
node 1 and node 2 if node 0 fills up.
This patch changes the node_demotion data structure to support multiple
target nodes, and establishes the migration path to support multiple
target nodes with validating if the node distance is the best or not.
available: 3 nodes (0-2)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
node 0 size: 62153 MB
node 0 free: 55135 MB
node 1 cpus:
node 1 size: 127007 MB
node 1 free: 126930 MB
node 2 cpus:
node 2 size: 126968 MB
node 2 free: 126878 MB
node distances:
node 0 1 2
0: 10 20 20
1: 20 10 20
2: 20 20 10
Link: https://lkml.kernel.org/r/00728da107789bb4ed9e0d28b1d08fd8056af2ef.1636697263.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: zhongjiang-ali <zhongjiang-ali@linux.alibaba.com>
Cc: Xunlei Pang <xlpang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now the migrate_pages() has changed to return the number of {normal
page, THP, hugetlb} instead, thus we should not use the return value to
calculate the number of pages migrated successfully. Instead we can
just use the 'nr_succeeded' which indicates the number of normal pages
migrated successfully to calculate the non-migrated pages in
trace_mm_compaction_migratepages().
Link: https://lkml.kernel.org/r/b4225251c4bec068dcd90d275ab7de88a39e2bd7.1636275127.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Correct the migration stats for hugetlb with using compound_nr() instead
of thp_nr_pages(), meanwhile change 'nr_failed_pages' to record the
number of normal pages failed to migrate, including THP and hugetlb, and
'nr_succeeded' will record the number of normal pages migrated
successfully.
[baolin.wang@linux.alibaba.com: fix docs, per Mike]
Link: https://lkml.kernel.org/r/141bdfc6-f898-3cc3-f692-726c5f6cb74d@linux.alibaba.com
Link: https://lkml.kernel.org/r/71a4b6c22f208728fe8c78ad26375436c4ff9704.1636275127.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Improve the migration stats".
According to talk with Zi Yan [1], this patch set changes the return
value of migrate_pages() to avoid returning a number which is larger
than the number of pages the users tried to migrate by move_pages()
syscall. Also fix the hugetlb migration stats and migration stats in
trace_mm_compaction_migratepages().
[1] https://lore.kernel.org/linux-mm/7E44019D-2A5D-4BA7-B4D5-00D4712F1687@nvidia.com/
This patch (of 3):
As Zi Yan pointed out, the syscall move_pages() can return a
non-migrated number larger than the number of pages the users tried to
migrate, when a THP page is failed to migrate. This is confusing for
users.
Since other migration scenarios do not care about the actual
non-migrated number of pages except the memory compaction migration
which will fix in following patch. Thus we can change the return value
to return the number of {normal page, THP, hugetlb} instead to avoid
this issue, and the number of THP splits will be considered as the
number of non-migrated THP, no matter how many subpages of the THP are
migrated successfully. Meanwhile we should still keep the migration
counters using the number of normal pages.
Link: https://lkml.kernel.org/r/cover.1636275127.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/6486fabc3e8c66ff613e150af25e89b3147977a6.1636275127.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Co-developed-by: Zi Yan <ziy@nvidia.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pass "end - 1" instead of "end" when walking the interval tree in
hugetlb_vmdelete_list() to fix an inclusive vs. exclusive bug. The two
callers that pass a non-zero "end" treat it as exclusive, whereas the
interval tree iterator expects an inclusive "last". E.g. punching a
hole in a file that precisely matches the size of a single hugepage,
with a vma starting right on the boundary, will result in
unmap_hugepage_range() being called twice, with the second call having
start==end.
The off-by-one error doesn't cause functional problems as
__unmap_hugepage_range() turns into a massive nop due to
short-circuiting its for-loop on "address < end". But, the mmu_notifier
invocations to invalid_range_{start,end}() are passed a bogus zero-sized
range, which may be unexpected behavior for secondary MMUs.
The bug was exposed by commit ed922739c9 ("KVM: Use interval tree to
do fast hva lookup in memslots"), currently queued in the KVM tree for
5.17, which added a WARN to detect ranges with start==end.
Link: https://lkml.kernel.org/r/20211228234257.1926057-1-seanjc@google.com
Fixes: 1bfad99ab4 ("hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to delete")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reported-by: syzbot+4e697fe80a31aa7efe21@syzkaller.appspotmail.com
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The OOM kill sysrq (alt+sysrq+F) should allow the user to kill the
process with the highest OOM badness with a single execution.
However, at the moment, the OOM kill can bail out if an OOM notifier
(e.g. the i915 one) says that it reclaimed a tiny amount of memory from
somewhere. That's probably not what the user wants, so skip the bailout
if the OOM was triggered via sysrq.
Link: https://lkml.kernel.org/r/20220106102605.635656-1-jannh@google.com
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix kernel-doc warnings in mempolicy.c:
mempolicy.c:139: warning: No description found for return value of 'numa_map_to_online_node'
mempolicy.c:2165: warning: Excess function parameter 'node' description in 'alloc_pages_vma'
mempolicy.c:2973: warning: No description found for return value of 'mpol_parse_str'
Link: https://lkml.kernel.org/r/20211213233216.5477-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This syscall can be used to set a home node for the MPOL_BIND and
MPOL_PREFERRED_MANY memory policy. Users should use this syscall after
setting up a memory policy for the specified range as shown below.
mbind(p, nr_pages * page_size, MPOL_BIND, new_nodes->maskp,
new_nodes->size + 1, 0);
sys_set_mempolicy_home_node((unsigned long)p, nr_pages * page_size,
home_node, 0);
The syscall allows specifying a home node/preferred node from which
kernel will fulfill memory allocation requests first.
For address range with MPOL_BIND memory policy, if nodemask specifies
more than one node, page allocations will come from the node in the
nodemask with sufficient free memory that is closest to the home
node/preferred node.
For MPOL_PREFERRED_MANY if the nodemask specifies more than one node,
page allocation will come from the node in the nodemask with sufficient
free memory that is closest to the home node/preferred node. If there
is not enough memory in all the nodes specified in the nodemask, the
allocation will be attempted from the closest numa node to the home node
in the system.
This helps applications to hint at a memory allocation preference node
and fallback to _only_ a set of nodes if the memory is not available on
the preferred node. Fallback allocation is attempted from the node
which is nearest to the preferred node.
This helps applications to have control on memory allocation numa nodes
and avoids default fallback to slow memory NUMA nodes. For example a
system with NUMA nodes 1,2 and 3 with DRAM memory and 10, 11 and 12 of
slow memory
new_nodes = numa_bitmask_alloc(nr_nodes);
numa_bitmask_setbit(new_nodes, 1);
numa_bitmask_setbit(new_nodes, 2);
numa_bitmask_setbit(new_nodes, 3);
p = mmap(NULL, nr_pages * page_size, protflag, mapflag, -1, 0);
mbind(p, nr_pages * page_size, MPOL_BIND, new_nodes->maskp, new_nodes->size + 1, 0);
sys_set_mempolicy_home_node(p, nr_pages * page_size, 2, 0);
This will allocate from nodes closer to node 2 and will make sure the
kernel will only allocate from nodes 1, 2, and 3. Memory will not be
allocated from slow memory nodes 10, 11, and 12. This differs from
default MPOL_BIND behavior in that with default MPOL_BIND the allocation
will be attempted from node closer to the local node. One of the
reasons to specify a home node is to allow allocations from cpu less
NUMA node and its nearby NUMA nodes.
With MPOL_PREFERRED_MANY on the other hand will first try to allocate
from the closest node to node 2 from the node list 1, 2 and 3. If those
nodes don't have enough memory, kernel will allocate from slow memory
node 10, 11 and 12 which ever is closer to node 2.
Link: https://lkml.kernel.org/r/20211202123810.267175-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: add new syscall set_mempolicy_home_node", v6.
This patch (of 3):
A followup patch will enable setting a home node with
MPOL_PREFERRED_MANY memory policy. To facilitate that switch to using
policy_node helper. There is no functional change in this patch.
Link: https://lkml.kernel.org/r/20211202123810.267175-1-aneesh.kumar@linux.ibm.com
Link: https://lkml.kernel.org/r/20211202123810.267175-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In unset_migratetype_isolate(), we can bypass the call to
move_freepages_block() for non-buddy pages.
It will save a few cpu cycles for some situations such as cma and
hugetlb when allocating continue pages, in these situation function
alloc_contig_pages will be called.
alloc_contig_pages
__alloc_contig_migrate_range
isolate_freepages_range ==> pages has been remove from buddy
undo_isolate_page_range
unset_migratetype_isolate ==> can directly set migratetype
[osalvador@suse.de: changelog tweak]
Link: https://lkml.kernel.org/r/20211229033649.2760586-1-chenwandun@huawei.com
Fixes: 3c605096d3 ("mm/page_alloc: restrict max order of merging on isolated pageblock")
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Wang Kefeng <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drop_slab_node is only used in drop_slab. So remove it's declaration
from header file and add keyword static for it's definition.
Link: https://lkml.kernel.org/r/20211111062445.5236-1-ligang.bdlg@bytedance.com
Signed-off-by: Gang Li <ligang.bdlg@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The message for commit f5c7329718 ("userfaultfd/selftests: fix hugetlb
area allocations") says there is no need to create a hugetlb file in the
non-shared testing case. However, the commit did not actually change
the code to prevent creation of the file.
While it is technically true that there is no need to create and use a
hugetlb file in the case of non-shared-testing, it is useful. This is
because 'hole punching' of a hugetlb file has the potentially incorrect
side effect of also removing pages from private mappings. The
userfaultfd test relies on this side effect for removing pages from the
destination buffer during rounds of stress testing.
Remove the incomplete code that was added to deal with no hugetlb file.
Just keep the code that prevents reserves from being created for the
destination area.
Link: https://lkml.kernel.org/r/20220104021729.111006-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mina Almasry <almasrymina@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>
This allow test to continue with interruptions like gdb.
Link: https://lkml.kernel.org/r/20211115135219.85881-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The hugetlb cgroup reservation test charge_reserved_hugetlb.sh assume
that no cgroup filesystems are mounted before running the test. That is
not true in many cases. As a result, the test fails to run. Fix that
by querying the current cgroup mount setting and using the existing
cgroup setup instead before attempting to freshly mount a cgroup
filesystem.
Similar change is also made for hugetlb_reparenting_test.sh as well,
though it still has problem if cgroup v2 isn't used.
The patched test scripts were run on a centos 8 based system to verify
that they ran properly.
Link: https://lkml.kernel.org/r/20220106201359.1646575-1-longman@redhat.com
Fixes: 29750f71a9 ("hugetlb_cgroup: add hugetlb_cgroup reservation tests")
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Mina Almasry <almasrymina@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are interfaces to adjust max_ptes_none, max_ptes_swap,
max_ptes_shared values, see
/sys/kernel/mm/transparent_hugepage/khugepaged/.
But system administrator may not know which value is the best. So Add
those events to support adjusting max_ptes_* to suitable values.
For example, if default max_ptes_swap value causes too much failures,
and system uses zram whose IO is fast, administrator could increase
max_ptes_swap until THP_SCAN_EXCEED_SWAP_PTE not increase anymore.
Link: https://lkml.kernel.org/r/20211225094036.574157-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Saravanan D <saravanand@fb.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The hugetlb vma mremap() test currently maps 1GB of memory to trigger
pmd sharing and make sure that 'unshare' path in mremap code works. The
test originally only mapped 10MB of memory (as specified by the header
comment) but was later modified to 1GB to tackle this case.
However, not all machines will have 1GB of memory to spare for this
test. Adding a mapping size arg will allow run_vmtest.sh to pass an
adequate mapping size, while allowing users to run the test
independently with arbitrary size mappings.
Link: https://lkml.kernel.org/r/20211124203805.3700355-1-yosryahmed@google.com
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For hugetlb backed jobs/VMs it's critical to understand the numa
information for the memory backing these jobs to deliver optimal
performance.
Currently this technically can be queried from /proc/self/numa_maps, but
there are significant issues with that. Namely:
1. Memory can be mapped or unmapped.
2. numa_maps are per process and need to be aggregated across all
processes in the cgroup. For shared memory this is more involved as
the userspace needs to make sure it doesn't double count shared
mappings.
3. I believe querying numa_maps needs to hold the mmap_lock which adds
to the contention on this lock.
For these reasons I propose simply adding hugetlb.*.numa_stat file,
which shows the numa information of the cgroup similarly to
memory.numa_stat.
On cgroup-v2:
cat /sys/fs/cgroup/unified/test/hugetlb.2MB.numa_stat
total=2097152 N0=2097152 N1=0
On cgroup-v1:
cat /sys/fs/cgroup/hugetlb/test/hugetlb.2MB.numa_stat
total=2097152 N0=2097152 N1=0
hierarichal_total=2097152 N0=2097152 N1=0
This patch was tested manually by allocating hugetlb memory and querying
the hugetlb.*.numa_stat file of the cgroup and its parents.
[colin.i.king@googlemail.com: fix spelling mistake "hierarichal" -> "hierarchical"]
Link: https://lkml.kernel.org/r/20211125090635.23508-1-colin.i.king@gmail.com
[keescook@chromium.org: fix copy/paste array assignment]
Link: https://lkml.kernel.org/r/20211203065647.2819707-1-keescook@chromium.org
Link: https://lkml.kernel.org/r/20211123001020.4083653-1-almasrymina@google.com
Signed-off-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jue Wang <juew@google.com>
Cc: Yang Yao <ygyao@google.com>
Cc: Joanna Li <joannali@google.com>
Cc: Cannon Matthews <cannonmatthews@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>