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1186246 commits

Author SHA1 Message Date
Christoph Hellwig
219580eea1 iomap: update ki_pos in iomap_file_buffered_write
All callers of iomap_file_buffered_write need to updated ki_pos, move it
into common code.

Link: https://lkml.kernel.org/r/20230601145904.1385409-8-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:53 -07:00
Christoph Hellwig
c402a9a943 filemap: add a kiocb_invalidate_post_direct_write helper
Add a helper to invalidate page cache after a dio write.

Link: https://lkml.kernel.org/r/20230601145904.1385409-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:53 -07:00
Christoph Hellwig
e003f74afb filemap: add a kiocb_invalidate_pages helper
Factor out a helper that calls filemap_write_and_wait_range and
invalidate_inode_pages2_range for the range covered by a write kiocb or
returns -EAGAIN if the kiocb is marked as nowait and there would be pages
to write or invalidate.

Link: https://lkml.kernel.org/r/20230601145904.1385409-6-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:52 -07:00
Christoph Hellwig
3c435a0fe3 filemap: add a kiocb_write_and_wait helper
Factor out a helper that does filemap_write_and_wait_range for the range
covered by a read kiocb, or returns -EAGAIN if the kiocb is marked as
nowait and there would be pages to write.

Link: https://lkml.kernel.org/r/20230601145904.1385409-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:52 -07:00
Christoph Hellwig
182c25e9c1 filemap: update ki_pos in generic_perform_write
All callers of generic_perform_write need to updated ki_pos, move it into
common code.

Link: https://lkml.kernel.org/r/20230601145904.1385409-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:52 -07:00
Christoph Hellwig
936e114a24 iomap: update ki_pos a little later in iomap_dio_complete
Move the ki_pos update down a bit to prepare for a better common helper
that invalidates pages based of an iocb.

Link: https://lkml.kernel.org/r/20230601145904.1385409-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:52 -07:00
Christoph Hellwig
0d625446d0 backing_dev: remove current->backing_dev_info
Patch series "cleanup the filemap / direct I/O interaction", v4.

This series cleans up some of the generic write helper calling conventions
and the page cache writeback / invalidation for direct I/O.  This is a
spinoff from the no-bufferhead kernel project, for which we'll want to an
use iomap based buffered write path in the block layer.


This patch (of 12):

The last user of current->backing_dev_info disappeared in commit
b9b1335e64 ("remove bdi_congested() and wb_congested() and related
functions").  Remove the field and all assignments to it.

Link: https://lkml.kernel.org/r/20230601145904.1385409-1-hch@lst.de
Link: https://lkml.kernel.org/r/20230601145904.1385409-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:51 -07:00
Domenico Cerasuolo
e0228d590b mm: zswap: shrink until can accept
This update addresses an issue with the zswap reclaim mechanism, which
hinders the efficient offloading of cold pages to disk, thereby
compromising the preservation of the LRU order and consequently
diminishing, if not inverting, its performance benefits.

The functioning of the zswap shrink worker was found to be inadequate, as
shown by basic benchmark test.  For the test, a kernel build was utilized
as a reference, with its memory confined to 1G via a cgroup and a 5G swap
file provided.  The results are presented below, these are averages of
three runs without the use of zswap:

real 46m26s
user 35m4s
sys 7m37s

With zswap (zbud) enabled and max_pool_percent set to 1 (in a 32G
system), the results changed to:

real 56m4s
user 35m13s
sys 8m43s

written_back_pages: 18
reject_reclaim_fail: 0
pool_limit_hit:1478

Besides the evident regression, one thing to notice from this data is the
extremely low number of written_back_pages and pool_limit_hit.

The pool_limit_hit counter, which is increased in zswap_frontswap_store
when zswap is completely full, doesn't account for a particular scenario:
once zswap hits his limit, zswap_pool_reached_full is set to true; with
this flag on, zswap_frontswap_store rejects pages if zswap is still above
the acceptance threshold.  Once we include the rejections due to
zswap_pool_reached_full && !zswap_can_accept(), the number goes from 1478
to a significant 21578266.

Zswap is stuck in an undesirable state where it rejects pages because it's
above the acceptance threshold, yet fails to attempt memory reclaimation. 
This happens because the shrink work is only queued when
zswap_frontswap_store detects that it's full and the work itself only
reclaims one page per run.

This state results in hot pages getting written directly to disk, while
cold ones remain memory, waiting only to be invalidated.  The LRU order is
completely broken and zswap ends up being just an overhead without
providing any benefits.

This commit applies 2 changes: a) the shrink worker is set to reclaim
pages until the acceptance threshold is met and b) the task is also
enqueued when zswap is not full but still above the threshold.

Testing this suggested update showed much better numbers:

real 36m37s
user 35m8s
sys 9m32s

written_back_pages: 10459423
reject_reclaim_fail: 12896
pool_limit_hit: 75653

Link: https://lkml.kernel.org/r/20230526183227.793977-1-cerasuolodomenico@gmail.com
Fixes: 45190f01dd ("mm/zswap.c: add allocation hysteresis if pool limit is hit")
Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:51 -07:00
Haifeng Xu
e3d9b45fb1 mm/mm_init.c: move set_pageblock_order() to free_area_init()
pageblock_order only needs to be set once, there is no need to initialize
it in every zone/node.

Link: https://lkml.kernel.org/r/20230601063536.26882-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:51 -07:00
Xin Hao
1661867027 mm: khugepaged: avoid pointless allocation for "struct mm_slot"
In __khugepaged_enter(), if "mm->flags" with MMF_VM_HUGEPAGE bit is set,
the "mm_slot" will be released and return, so we can call mm_slot_alloc()
after test_and_set_bit().

Link: https://lkml.kernel.org/r/20230531095817.11012-1-xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Andrew Morton <akpm@linux-foudation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:51 -07:00
Tetsuo Handa
3b11edf1f2 mm/page_alloc: don't wake kswapd from rmqueue() unless __GFP_KSWAPD_RECLAIM is specified
Commit 73444bc4d8 ("mm, page_alloc: do not wake kswapd with zone lock
held") moved wakeup_kswapd() from steal_suitable_fallback() to rmqueue()
using ZONE_BOOSTED_WATERMARK flag.

Only allocation contexts that include ALLOC_KSWAPD (which corresponds to
__GFP_KSWAPD_RECLAIM) should wake kswapd, for callers are supposed to
remove __GFP_KSWAPD_RECLAIM if trying to hold pgdat->kswapd_wait has a
risk of deadlock.  But since zone->flags is a shared variable, a thread
doing !__GFP_KSWAPD_RECLAIM allocation request might observe this flag
being set immediately after another thread doing __GFP_KSWAPD_RECLAIM
allocation request set this flag, causing possibility of deadlock.

Link: https://lkml.kernel.org/r/c3c3dacf-dd3b-77c9-f96a-d0982b4b2a4f@I-love.SAKURA.ne.jp
Fixes: 73444bc4d8 ("mm, page_alloc: do not wake kswapd with zone lock held")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:50 -07:00
Haifeng Xu
837c2ba56d mm/mm_init.c: remove free_area_init_memoryless_node()
free_area_init_memoryless_node() is just a wrapper of
free_area_init_node(), remove it to clean up.

Link: https://lkml.kernel.org/r/20230528045720.4835-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:50 -07:00
Yin Fengwei
deedad80f6 THP: avoid lock when check whether THP is in deferred list
free_transhuge_page() acquires split queue lock then check whether the THP
was added to deferred list or not.  It brings high deferred queue lock
contention.

It's safe to check whether the THP is in deferred list or not without
holding the deferred queue lock in free_transhuge_page() because when code
hit free_transhuge_page(), there is no one tries to add the folio to
_deferred_list.

Running page_fault1 of will-it-scale + order 2 folio for anonymous
mapping with 96 processes on an Ice Lake 48C/96T test box, we could
see the 61% split_queue_lock contention:
-   63.02%     0.01%  page_fault1_pro  [kernel.kallsyms]         [k] free_transhuge_page
   - 63.01% free_transhuge_page
      + 62.91% _raw_spin_lock_irqsave

With this patch applied, the split_queue_lock contention is less
than 1%.

Link: https://lkml.kernel.org/r/20230429082759.1600796-2-fengwei.yin@intel.com
Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:50 -07:00
Huang Ying
a95722a047 swap: comments get_swap_device() with usage rule
The general rule to use a swap entry is as follows.

When we get a swap entry, if there aren't some other ways to prevent
swapoff, such as the folio in swap cache is locked, page table lock is
held, etc., the swap entry may become invalid because of swapoff.
Then, we need to enclose all swap related functions with
get_swap_device() and put_swap_device(), unless the swap functions
call get/put_swap_device() by themselves.

Add the rule as comments of get_swap_device().

Link: https://lkml.kernel.org/r/20230529061355.125791-6-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Chris Li (Google) <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:50 -07:00
Huang Ying
c07aee4f82 swap: remove get/put_swap_device() in __swap_duplicate()
__swap_duplicate() is called by

- swap_shmem_alloc(): the folio in swap cache is locked.

- copy_nonpresent_pte() -> swap_duplicate() and try_to_unmap_one() ->
  swap_duplicate(): the page table lock is held.

- __read_swap_cache_async() -> swapcache_prepare(): enclosed with
  get/put_swap_device() in __read_swap_cache_async() already.

So, it's safe to remove get/put_swap_device() in __swap_duplicate().

Link: https://lkml.kernel.org/r/20230529061355.125791-5-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Chris Li (Google) <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:50 -07:00
Huang Ying
3ecdeb0f87 swap: remove __swp_swapcount()
__swp_swapcount() just encloses the calling to swap_swapcount() with
get/put_swap_device().  It is called in __read_swap_cache_async() only,
which encloses the calling with get/put_swap_device() already.  So,
__read_swap_cache_async() can call swap_swapcount() directly.

Link: https://lkml.kernel.org/r/20230529061355.125791-4-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Chris Li (Google) <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:49 -07:00
Huang Ying
46a774d3ea swap, __read_swap_cache_async(): enlarge get/put_swap_device protection range
This makes the function a little easier to be understood because we don't
need to consider swapoff.  And this makes it possible to remove
get/put_swap_device() calling in some functions called by
__read_swap_cache_async().

Link: https://lkml.kernel.org/r/20230529061355.125791-3-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Chris Li (Google) <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:49 -07:00
Huang Ying
f9f956b550 swap: remove get/put_swap_device() in __swap_count()
Patch series "swap: cleanup get/put_swap_device() usage", v3.

The general rule to use a swap entry is as follows.

When we get a swap entry, if there aren't some other ways to prevent
swapoff, such as the folio in swap cache is locked, page table lock is
held, etc., the swap entry may become invalid because of swapoff.  Then,
we need to enclose all swap related functions with get_swap_device() and
put_swap_device(), unless the swap functions call get/put_swap_device() by
themselves.

Based on the above rule, all get/put_swap_device() usage are checked and
cleaned up if necessary.


This patch (of 5):

get/put_swap_device() are added to __swap_count() in commit
eb085574a7 ("mm, swap: fix race between swapoff and some swap
operations").  Later, in commit 2799e77529 ("swap: fix
do_swap_page() race with swapoff"), get/put_swap_device() are added to
do_swap_page().  And they enclose the only call site of
__swap_count().  So, it's safe to remove get/put_swap_device() in
__swap_count() now.

Link: https://lkml.kernel.org/r/20230529061355.125791-1-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20230529061355.125791-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Chris Li (Google) <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:49 -07:00
Haifeng Xu
1c2d252f5b mm/mm_init.c: do not calculate zone_start_pfn/zone_end_pfn in zone_absent_pages_in_node()
In calculate_node_totalpages(), zone_start_pfn/zone_end_pfn are already
calculated in zone_spanned_pages_in_node(), so use them as parameters
instead of node_start_pfn/node_end_pfn and the duplicated calculation
process can de dropped.

Link: https://lkml.kernel.org/r/20230526085251.1977-2-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Suggested-by: Mike Rapoport <rppt@kernel.org>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Haifeng Xu <haifeng.xu@shopee.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:49 -07:00
Haifeng Xu
ba1b67c79c mm/mm_init.c: introduce reset_memoryless_node_totalpages()
Currently, no matter whether a node actually has memory or not,
calculate_node_totalpages() is used to account number of pages in
zone/node.  However, for node without memory, these unnecessary
calculations can be skipped.  All the zone/node page counts can be set to
0 directly.  So introduce reset_memoryless_node_totalpages() to perform
this action.

Furthermore, calculate_node_totalpages() only gets called for the node
with memory.

Link: https://lkml.kernel.org/r/20230526085251.1977-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Suggested-by: Mike Rapoport <rppt@kernel.org>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:48 -07:00
SeongJae Park
da9698105c Docs/mm/damon/design: add a section for the modules layer
Add a section for covering DAMON modules layer to the design document.

Link: https://lkml.kernel.org/r/20230525214314.5204-11-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>
2023-06-09 16:25:48 -07:00
SeongJae Park
f508a0fbd3 Docs/mm/damon/design: add a section for DAMON core API
Add a section covering the API of DAMON core layer on the design document.

Link: https://lkml.kernel.org/r/20230525214314.5204-10-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>
2023-06-09 16:25:48 -07:00
SeongJae Park
b138878609 Docs/mm/damon/design: add sections for advanced features of DAMOS
Add sections for advanced features of DAMOS including quotas,
prioritization, watermarks, and filters of DAMOS on the design document.

Link: https://lkml.kernel.org/r/20230525214314.5204-9-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>
2023-06-09 16:25:48 -07:00
SeongJae Park
2dc4e6a509 Docs/mm/damon/design: add sections for basic parts of DAMOS
DAMOS is an important part of DAMON, but the design doc is not covering
it.  Add sections for covering the basic part of DAMOS.

Link: https://lkml.kernel.org/r/20230525214314.5204-8-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>
2023-06-09 16:25:47 -07:00
SeongJae Park
eaabfa4321 Docs/mm/damon/design: add a section for the relation between Core and Modules layer
Add overall desription of the interface and the relation between the Core
and the Modules layer under 'Overall Architecture' section.

Link: https://lkml.kernel.org/r/20230525214314.5204-7-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>
2023-06-09 16:25:47 -07:00
SeongJae Park
69e7b88cea Docs/mm/damon/design: rewrite configurable layers
The 'Configurable Operations Set' section is a little bit outdated. 
Update the text.

Link: https://lkml.kernel.org/r/20230525214314.5204-6-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>
2023-06-09 16:25:47 -07:00
SeongJae Park
e168962dbf Docs/mm/damon/design: update the layout based on the layers
DAMON design document is describing only the operations set layer and
monitoring part of the core logic.  Update the layout based on the DAMON's
layers, so that more parts of DAMON including DAMOS core logic and DAMON
modules can easily be added.

Link: https://lkml.kernel.org/r/20230525214314.5204-5-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>
2023-06-09 16:25:47 -07:00
SeongJae Park
45b849df7d Docs/mm/damon/design: add a section for overall architecture
The design doc is missing overall picture of DAMON.  Add a section for
overall architeucture and layers.

Link: https://lkml.kernel.org/r/20230525214314.5204-4-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>
2023-06-09 16:25:47 -07:00
SeongJae Park
73dc57e4ef Docs/mm/damon/maintainer-profile: fix typos and grammar errors
Fix a few typos and grammar erros in DAMON Maintainer Profile document.

Link: https://lkml.kernel.org/r/20230525214314.5204-3-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>
2023-06-09 16:25:46 -07:00
SeongJae Park
c6bb975aa6 Docs/mm/damon/faq: remove old questions
Patch series "Docs/mm/damon: Minor fixes and design doc update".

Some of the DAMON documents are outdated, or having minor typos or grammar
erros.  Especially, the design doc has not updated for DAMOS, which is an
important part of DAMON.  Fix the minor issues and update documents.


This patch (of 10):

The first two questions of DAMON faqs have raised when DAMON patches were
first submitted.  More than one year has passed since DAMON patches get
merged in the mainline, and that kind of questions are not asked nowadays.
Remove the questions.

Link: https://lkml.kernel.org/r/20230525214314.5204-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20230525214314.5204-2-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>
2023-06-09 16:25:46 -07:00
Kalesh Singh
3af0191a59 Multi-gen LRU: fix workingset accounting
On Android app cycle workloads, MGLRU showed a significant reduction in
workingset refaults although pgpgin/pswpin remained relatively unchanged. 
This indicated MGLRU may be undercounting workingset refaults.

This has impact on userspace programs, like Android's LMKD, that monitor
workingset refault statistics to detect thrashing.

It was found that refaults were only accounted if the MGLRU shadow entry
was for a recently evicted folio.  However, recently evicted folios should
be accounted as workingset activation, and refaults should be accounted
regardless of recency.

Fix MGLRU's workingset refault and activation accounting to more closely
match that of the conventional active/inactive LRU.

Link: https://lkml.kernel.org/r/20230523205922.3852731-1-kaleshsingh@google.com
Fixes: ac35a49023 ("mm: multi-gen LRU: minimal implementation")
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reported-by: Charan Teja Kalla <quic_charante@quicinc.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Cc: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:46 -07:00
Peng Zhang
06b27ce36a maple_tree: relocate the declaration of mas_empty_area_rev().
Relocate the declaration of mas_empty_area_rev() so that mas_empty_area()
and mas_empty_area_rev() are together.

Link: https://lkml.kernel.org/r/20230524031247.65949-11-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:46 -07:00
Peng Zhang
7a03ae3920 maple_tree: simplify and clean up mas_wr_node_store()
Simplify and clean up mas_wr_node_store(), remove unnecessary code.

Link: https://lkml.kernel.org/r/20230524031247.65949-10-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:45 -07:00
Peng Zhang
e6d1ffd611 maple_tree: rework mas_wr_slot_store() to be cleaner and more efficient.
Get whether the two gaps to be overwritten are empty to avoid calling
mas_update_gap() all the time.  Also clean up the code and add comments.

Link: https://lkml.kernel.org/r/20230524031247.65949-9-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:45 -07:00
Peng Zhang
2e1da329b4 maple_tree: add comments and some minor cleanups to mas_wr_append()
Add comment for mas_wr_append(), move mas_update_gap() into
mas_wr_append(), and other cleanups to make mas_wr_modify() cleaner.

Link: https://lkml.kernel.org/r/20230524031247.65949-8-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:45 -07:00
Peng Zhang
c6fc9e4a5c maple_tree: add mas_wr_new_end() to calculate new_end accurately
The previous new_end calculation is inaccurate, because it assumes that
two new pivots must be added (this is inaccurate), and sometimes it will
miss the fast path and enter the slow path.  Add mas_wr_new_end() to
accurately calculate new_end to make the conditions for entering the fast
path more accurate.

Link: https://lkml.kernel.org/r/20230524031247.65949-7-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:45 -07:00
Peng Zhang
8c995a6314 maple_tree: make the code symmetrical in mas_wr_extend_null()
Just make the code symmetrical to improve readability.

Link: https://lkml.kernel.org/r/20230524031247.65949-6-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:44 -07:00
Peng Zhang
bc147f0f70 maple_tree: simplify mas_is_span_wr()
Make the code for detecting spanning writes more concise.

Link: https://lkml.kernel.org/r/20230524031247.65949-5-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:44 -07:00
Peng Zhang
14c4b5ab6a maple_tree: fix the arguments to __must_hold()
Fix the arguments to __must_hold() to make sparse work.

Link: https://lkml.kernel.org/r/20230524031247.65949-4-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:44 -07:00
Peng Zhang
c2aa6f5328 maple_tree: drop mas_{rev_}alloc() and mas_fill_gap()
mas_{rev_}alloc() and mas_fill_gap() are no longer used, delete them.

Link: https://lkml.kernel.org/r/20230524031247.65949-3-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:44 -07:00
Peng Zhang
523716770e maple_tree: rework mtree_alloc_{range,rrange}()
Patch series "Clean ups for maple tree", v4.

Some clean ups, mainly to make the code of maple tree more concise.
This patchset has passed the self-test.


This patch (of 10):

Use mas_empty_area{_rev}() to refactor mtree_alloc_{range,rrange}()

Link: https://lkml.kernel.org/r/20230524031247.65949-2-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:43 -07:00
Lars R. Damerow
e0e0b4126c mm/memcontrol: export memcg.swap watermark via sysfs for v2 memcg
This patch is similar to commit 8e20d4b332 ("mm/memcontrol: export
memcg->watermark via sysfs for v2 memcg"), but exports the swap counter's
watermark.

We allocate jobs to our compute farm using heuristics determined by memory
and swap usage from previous jobs.  Tracking the peak swap usage for new
jobs is important for determining when jobs are exceeding their expected
bounds, or when our baseline metrics are getting outdated.

Our toolset was written to use the "memory.memsw.max_usage_in_bytes" file
in cgroups v1, and altering it to poll cgroups v2's "memory.swap.current"
would give less accurate results as well as add complication to the code. 
Having this watermark exposed in sysfs is much preferred.

Link: https://lkml.kernel.org/r/20230524181734.125696-1-lars@pixar.com
Signed-off-by: Lars R. Damerow <lars@pixar.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:43 -07:00
Tu Jinjiang
283ebdee2d mm: shmem: fix UAF bug in shmem_show_options()
shmem_show_options() uses sbinfo->mpol without adding it's refcnt. This
may lead to race with replacement of the mpol by remount. The execution
sequence is as follows.

       CPU0                                   CPU1
shmem_show_options()                        shmem_reconfigure()
    shmem_show_mpol(seq, sbinfo->mpol)          mpol = sbinfo->mpol
                                                mpol_put(mpol)
        mpol->mode

The KASAN report is as follows.

BUG: KASAN: slab-use-after-free in shmem_show_options+0x21b/0x340
Read of size 2 at addr ffff888124324004 by task mount/2388

CPU: 2 PID: 2388 Comm: mount Not tainted 6.4.0-rc3-00017-g9d646009f65d-dirty #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x37/0x50
 print_report+0xd0/0x620
 ? shmem_show_options+0x21b/0x340
 ? __virt_addr_valid+0xf4/0x180
 ? shmem_show_options+0x21b/0x340
 kasan_report+0xb8/0xe0
 ? shmem_show_options+0x21b/0x340
 shmem_show_options+0x21b/0x340
 ? __pfx_shmem_show_options+0x10/0x10
 ? strchr+0x2c/0x50
 ? strlen+0x23/0x40
 ? seq_puts+0x7d/0x90
 show_vfsmnt+0x1e6/0x260
 ? __pfx_show_vfsmnt+0x10/0x10
 ? __kasan_kmalloc+0x7f/0x90
 seq_read_iter+0x57a/0x740
 vfs_read+0x2e2/0x4a0
 ? __pfx_vfs_read+0x10/0x10
 ? down_write_killable+0xb8/0x140
 ? __pfx_down_write_killable+0x10/0x10
 ? __fget_light+0xa9/0x1e0
 ? up_write+0x3f/0x80
 ksys_read+0xb8/0x150
 ? __pfx_ksys_read+0x10/0x10
 ? fpregs_assert_state_consistent+0x55/0x60
 ? exit_to_user_mode_prepare+0x2d/0x120
 do_syscall_64+0x3c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

 </TASK>

Allocated by task 2387:
 kasan_save_stack+0x22/0x50
 kasan_set_track+0x25/0x30
 __kasan_slab_alloc+0x59/0x70
 kmem_cache_alloc+0xdd/0x220
 mpol_new+0x83/0x150
 mpol_parse_str+0x280/0x4a0
 shmem_parse_one+0x364/0x520
 vfs_parse_fs_param+0xf8/0x1a0
 vfs_parse_fs_string+0xc9/0x130
 shmem_parse_options+0xb2/0x110
 path_mount+0x597/0xdf0
 do_mount+0xcd/0xf0
 __x64_sys_mount+0xbd/0x100
 do_syscall_64+0x3c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Freed by task 2389:
 kasan_save_stack+0x22/0x50
 kasan_set_track+0x25/0x30
 kasan_save_free_info+0x2e/0x50
 __kasan_slab_free+0x10e/0x1a0
 kmem_cache_free+0x9c/0x350
 shmem_reconfigure+0x278/0x370
 reconfigure_super+0x383/0x450
 path_mount+0xcc5/0xdf0
 do_mount+0xcd/0xf0
 __x64_sys_mount+0xbd/0x100
 do_syscall_64+0x3c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

The buggy address belongs to the object at ffff888124324000
 which belongs to the cache numa_policy of size 32
The buggy address is located 4 bytes inside of
 freed 32-byte region [ffff888124324000, ffff888124324020)
==================================================================

To fix the bug, shmem_get_sbmpol() / mpol_put() needs to be called
before / after shmem_show_mpol() call.

Link: https://lkml.kernel.org/r/20230525031640.593733-1-tujinjiang@huawei.com
Signed-off-by: Tu Jinjiang <tujinjiang@huawei.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:43 -07:00
Baolin Wang
a8d13355c6 mm: compaction: skip fast freepages isolation if enough freepages are isolated
I've observed that fast isolation often isolates more pages than
cc->migratepages, and the excess freepages will be released back to the
buddy system.  So skip fast freepages isolation if enough freepages are
isolated to save some CPU cycles.

Link: https://lkml.kernel.org/r/f39c2c07f2dba2732fd9c0843572e5bef96f7f67.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:43 -07:00
Baolin Wang
447ba88658 mm: compaction: add trace event for fast freepages isolation
The fast_isolate_freepages() can also isolate freepages, but we can not
know the fast isolation efficiency to understand the fast isolation
pressure.  So add a trace event to show some numbers to help to understand
the efficiency for fast freepages isolation.

Link: https://lkml.kernel.org/r/78d2932d0160d122c15372aceb3f2c45460a17fc.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:43 -07:00
Baolin Wang
8b71b499ff mm: compaction: only set skip flag if cc->no_set_skip_hint is false
To keep the same logic as test_and_set_skip(), only set the skip flag if
cc->no_set_skip_hint is false, which makes code more reasonable.

Link: https://lkml.kernel.org/r/0eb2cd2407ffb259ae6e3071e10f70f2d41d0f3e.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:42 -07:00
Baolin Wang
cf650342f8 mm: compaction: skip more fully scanned pageblock
In fast_isolate_around(), it assumes the pageblock is fully scanned if
cc->nr_freepages < cc->nr_migratepages after trying to isolate some free
pages, and will set skip flag to avoid scanning in future.  However this
can miss setting the skip flag for a fully scanned pageblock (returned
'start_pfn' is equal to 'end_pfn') in the case where cc->nr_freepages is
larger than cc->nr_migratepages.

So using the returned 'start_pfn' from isolate_freepages_block() and
'end_pfn' to decide if a pageblock is fully scanned makes more sense.  It
can also cover the case where cc->nr_freepages < cc->nr_migratepages,
which means the 'start_pfn' is usually equal to 'end_pfn' except some
uncommon fatal error occurs after non-strict mode isolation.

Link: https://lkml.kernel.org/r/f4efd2fa08735794a6d809da3249b6715ba6ad38.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:42 -07:00
Baolin Wang
2dbd90054f mm: compaction: change fast_isolate_freepages() to void type
No caller cares about the return value of fast_isolate_freepages(), void
it.

Link: https://lkml.kernel.org/r/759fca20b22ebf4c81afa30496837b9e0fb2e53b.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:42 -07:00
Baolin Wang
75990f6459 mm: compaction: drop the redundant page validation in update_pageblock_skip()
Patch series "Misc cleanups and improvements for compaction".

This series cantains some cleanups and improvements for compaction.


This patch (of 6):

The caller has validated the page before calling
update_pageblock_skip(), thus drop the redundant page validation in
update_pageblock_skip().

Link: https://lkml.kernel.org/r/5142e15b9295fe8c447dbb39b7907a20177a1413.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:42 -07:00
Thomas Gleixner
77e50af07f mm/vmalloc: dont purge usable blocks unnecessarily
Purging fragmented blocks is done unconditionally in several contexts:

  1) From drain_vmap_area_work(), when the number of lazy to be freed
     vmap_areas reached the threshold

  2) Reclaiming vmalloc address space from pcpu_get_vm_areas()

  3) _vm_unmap_aliases()

#1 There is no reason to zap fragmented vmap blocks unconditionally, simply
   because reclaiming all lazy areas drains at least

      32MB * fls(num_online_cpus())

   per invocation which is plenty.

#2 Reclaiming when running out of space or due to memory pressure makes a
   lot of sense

#3 _unmap_aliases() requires to touch everything because the caller has no
   clue which vmap_area used a particular page last and the vmap_area lost
   that information too.

   Except for the vfree + VM_FLUSH_RESET_PERMS case, which removes the
   vmap area first and then cares about the flush. That in turn requires
   a full walk of _all_ vmap areas including the one which was just
   added to the purge list.

   But as this has to be flushed anyway this is an opportunity to combine
   outstanding TLB flushes and do the housekeeping of purging freed areas,
   but like #1 there is no real good reason to zap usable vmap blocks
   unconditionally.

Add a @force_purge argument to the newly split out block purge function and
if not true only purge fragmented blocks which have less than 1/4 of their
capacity left.

Rename purge_vmap_area_lazy() to reclaim_and_purge_vmap_areas() to make it
clear what the function does.

[lstoakes@gmail.com: correct VMAP_PURGE_THRESHOLD check]
  Link: https://lkml.kernel.org/r/3e92ef61-b910-4576-88e7-cf43211fd4e7@lucifer.local
Link: https://lkml.kernel.org/r/20230525124504.864005691@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:41 -07:00