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author | Suren Baghdasaryan <surenb@google.com> | 2023-06-30 23:19:52 +0200 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-25 01:20:16 +0200 |
commit | b243dcbf2f13856e39e18df3a15a65f6fe33db85 (patch) | |
tree | 5bcb0ad2755dbb8a894258c24e10ded4685aca3b /mm/swap_state.c | |
parent | mm: memory-failure: fix potential page refcnt leak in memory_failure() (diff) | |
download | linux-b243dcbf2f13856e39e18df3a15a65f6fe33db85.tar.xz linux-b243dcbf2f13856e39e18df3a15a65f6fe33db85.zip |
swap: remove remnants of polling from read_swap_cache_async
Patch series "Per-VMA lock support for swap and userfaults", v7.
When per-VMA locks were introduced in [1] several types of page faults
would still fall back to mmap_lock to keep the patchset simple. Among
them are swap and userfault pages. The main reason for skipping those
cases was the fact that mmap_lock could be dropped while handling these
faults and that required additional logic to be implemented. Implement
the mechanism to allow per-VMA locks to be dropped for these cases.
First, change handle_mm_fault to drop per-VMA locks when returning
VM_FAULT_RETRY or VM_FAULT_COMPLETED to be consistent with the way
mmap_lock is handled. Then change folio_lock_or_retry to accept vm_fault
and return vm_fault_t which simplifies later patches. Finally allow swap
and uffd page faults to be handled under per-VMA locks by dropping per-VMA
and retrying, the same way it's done under mmap_lock. Naturally, once VMA
lock is dropped that VMA should be assumed unstable and can't be used.
This patch (of 6):
Commit [1] introduced IO polling support duding swapin to reduce swap read
latency for block devices that can be polled. However later commit [2]
removed polling support. Therefore it seems safe to remove do_poll
parameter in read_swap_cache_async and always call swap_readpage with
synchronous=false waiting for IO completion in folio_lock_or_retry.
[1] commit 23955622ff8d ("swap: add block io poll in swapin path")
[2] commit 9650b453a3d4 ("block: ignore RWF_HIPRI hint for sync dio")
Link: https://lkml.kernel.org/r/20230630211957.1341547-1-surenb@google.com
Link: https://lkml.kernel.org/r/20230630211957.1341547-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michel Lespinasse <michel@lespinasse.org>
Cc: Minchan Kim <minchan@google.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Punit Agrawal <punit.agrawal@bytedance.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/swap_state.c')
-rw-r--r-- | mm/swap_state.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/mm/swap_state.c b/mm/swap_state.c index d157862ba0a6..01f15139b7d9 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -526,15 +526,14 @@ fail_put_swap: */ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, struct vm_area_struct *vma, - unsigned long addr, bool do_poll, - struct swap_iocb **plug) + unsigned long addr, struct swap_iocb **plug) { bool page_was_allocated; struct page *retpage = __read_swap_cache_async(entry, gfp_mask, vma, addr, &page_was_allocated); if (page_was_allocated) - swap_readpage(retpage, do_poll, plug); + swap_readpage(retpage, false, plug); return retpage; } @@ -629,7 +628,7 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, struct swap_info_struct *si = swp_swap_info(entry); struct blk_plug plug; struct swap_iocb *splug = NULL; - bool do_poll = true, page_allocated; + bool page_allocated; struct vm_area_struct *vma = vmf->vma; unsigned long addr = vmf->address; @@ -637,7 +636,6 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, if (!mask) goto skip; - do_poll = false; /* Read a page_cluster sized and aligned cluster around offset. */ start_offset = offset & ~mask; end_offset = offset | mask; @@ -669,7 +667,7 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, lru_add_drain(); /* Push any new pages onto the LRU now */ skip: /* The page was likely read above, so no need for plugging here */ - return read_swap_cache_async(entry, gfp_mask, vma, addr, do_poll, NULL); + return read_swap_cache_async(entry, gfp_mask, vma, addr, NULL); } int init_swap_address_space(unsigned int type, unsigned long nr_pages) @@ -837,7 +835,7 @@ static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask, skip: /* The page was likely read above, so no need for plugging here */ return read_swap_cache_async(fentry, gfp_mask, vma, vmf->address, - ra_info.win == 1, NULL); + NULL); } /** |