From: Christoph Hellwig <hch@infradead.org> To: Jan Kara <jack@suse.cz> Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Christoph Hellwig <hch@infradead.org>, "Darrick J. Wong" <djwong@kernel.org>, Ted Tso <tytso@mit.edu>, Dave Chinner <david@fromorbit.com>, Matthew Wilcox <willy@infradead.org>, linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, Christoph Hellwig <hch@lst.de> Subject: Re: [PATCH 03/14] mm: Protect operations adding pages to page cache with invalidate_lock Date: Tue, 13 Jul 2021 07:25:05 +0100 [thread overview] Message-ID: <YO0xwY+q7d8rQE3f@infradead.org> (raw) In-Reply-To: <20210712165609.13215-3-jack@suse.cz> Still looks good. That being said the additional conditional locking in filemap_fault makes it fall over the readbility cliff for me. Something like this on top of your series would help: diff --git a/mm/filemap.c b/mm/filemap.c index fd3f94d36c49..0fad08331cf4 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3040,21 +3040,23 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) * Do we have something in the page cache already? */ page = find_get_page(mapping, offset); - if (likely(page) && !(vmf->flags & FAULT_FLAG_TRIED)) { + if (likely(page)) { /* - * We found the page, so try async readahead before - * waiting for the lock. + * We found the page, so try async readahead before waiting for + * the lock. */ - fpin = do_async_mmap_readahead(vmf, page); - } else if (!page) { + if (!(vmf->flags & FAULT_FLAG_TRIED)) + fpin = do_async_mmap_readahead(vmf, page); + if (unlikely(!PageUptodate(page))) { + filemap_invalidate_lock_shared(mapping); + mapping_locked = true; + } + } else { /* No page in the page cache at all */ count_vm_event(PGMAJFAULT); count_memcg_event_mm(vmf->vma->vm_mm, PGMAJFAULT); ret = VM_FAULT_MAJOR; fpin = do_sync_mmap_readahead(vmf); - } - - if (!page) { retry_find: /* * See comment in filemap_create_page() why we need @@ -3073,9 +3075,6 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) filemap_invalidate_unlock_shared(mapping); return VM_FAULT_OOM; } - } else if (unlikely(!PageUptodate(page))) { - filemap_invalidate_lock_shared(mapping); - mapping_locked = true; } if (!lock_page_maybe_drop_mmap(vmf, page, &fpin))
WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@infradead.org> To: Jan Kara <jack@suse.cz> Cc: linux-xfs@vger.kernel.org, Ted Tso <tytso@mit.edu>, linux-cifs@vger.kernel.org, "Darrick J. Wong" <djwong@kernel.org>, Dave Chinner <david@fromorbit.com>, Matthew Wilcox <willy@infradead.org>, linux-f2fs-devel@lists.sourceforge.net, Christoph Hellwig <hch@infradead.org>, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, ceph-devel@vger.kernel.org, linux-ext4@vger.kernel.org, Christoph Hellwig <hch@lst.de> Subject: Re: [f2fs-dev] [PATCH 03/14] mm: Protect operations adding pages to page cache with invalidate_lock Date: Tue, 13 Jul 2021 07:25:05 +0100 [thread overview] Message-ID: <YO0xwY+q7d8rQE3f@infradead.org> (raw) In-Reply-To: <20210712165609.13215-3-jack@suse.cz> Still looks good. That being said the additional conditional locking in filemap_fault makes it fall over the readbility cliff for me. Something like this on top of your series would help: diff --git a/mm/filemap.c b/mm/filemap.c index fd3f94d36c49..0fad08331cf4 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3040,21 +3040,23 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) * Do we have something in the page cache already? */ page = find_get_page(mapping, offset); - if (likely(page) && !(vmf->flags & FAULT_FLAG_TRIED)) { + if (likely(page)) { /* - * We found the page, so try async readahead before - * waiting for the lock. + * We found the page, so try async readahead before waiting for + * the lock. */ - fpin = do_async_mmap_readahead(vmf, page); - } else if (!page) { + if (!(vmf->flags & FAULT_FLAG_TRIED)) + fpin = do_async_mmap_readahead(vmf, page); + if (unlikely(!PageUptodate(page))) { + filemap_invalidate_lock_shared(mapping); + mapping_locked = true; + } + } else { /* No page in the page cache at all */ count_vm_event(PGMAJFAULT); count_memcg_event_mm(vmf->vma->vm_mm, PGMAJFAULT); ret = VM_FAULT_MAJOR; fpin = do_sync_mmap_readahead(vmf); - } - - if (!page) { retry_find: /* * See comment in filemap_create_page() why we need @@ -3073,9 +3075,6 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) filemap_invalidate_unlock_shared(mapping); return VM_FAULT_OOM; } - } else if (unlikely(!PageUptodate(page))) { - filemap_invalidate_lock_shared(mapping); - mapping_locked = true; } if (!lock_page_maybe_drop_mmap(vmf, page, &fpin)) _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
next prev parent reply other threads:[~2021-07-13 6:25 UTC|newest] Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-07-12 16:55 [PATCH 0/14 v9] fs: Hole punch vs page cache filling races Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 01/14] mm: Fix comments mentioning i_mutex Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 02/14] documentation: Sync file_operations members with reality Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-13 1:02 ` Darrick J. Wong 2021-07-13 1:02 ` [f2fs-dev] " Darrick J. Wong 2021-07-12 16:55 ` [PATCH 03/14] mm: Protect operations adding pages to page cache with invalidate_lock Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-13 1:25 ` Darrick J. Wong 2021-07-13 1:25 ` [f2fs-dev] " Darrick J. Wong 2021-07-13 11:11 ` Jan Kara 2021-07-13 11:11 ` [f2fs-dev] " Jan Kara 2021-07-13 6:25 ` Christoph Hellwig [this message] 2021-07-13 6:25 ` Christoph Hellwig 2021-07-13 12:35 ` Jan Kara 2021-07-13 12:35 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 04/14] mm: Add functions to lock invalidate_lock for two mappings Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 05/14] ext4: Convert to use mapping->invalidate_lock Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 06/14] ext2: Convert to using invalidate_lock Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 07/14] xfs: Refactor xfs_isilocked() Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:55 ` [PATCH 08/14] xfs: Convert to use invalidate_lock Jan Kara 2021-07-12 16:55 ` [f2fs-dev] " Jan Kara 2021-07-12 16:56 ` [PATCH 09/14] xfs: Convert double locking of MMAPLOCK to use VFS helpers Jan Kara 2021-07-12 16:56 ` [f2fs-dev] " Jan Kara 2021-07-12 16:56 ` [PATCH 10/14] zonefs: Convert to using invalidate_lock Jan Kara 2021-07-12 16:56 ` [f2fs-dev] " Jan Kara 2021-07-12 16:56 ` [PATCH 11/14] f2fs: " Jan Kara 2021-07-12 16:56 ` [f2fs-dev] " Jan Kara 2021-07-12 16:56 ` [PATCH 12/14] fuse: " Jan Kara 2021-07-12 16:56 ` [f2fs-dev] " Jan Kara 2021-07-12 16:56 ` [PATCH 13/14] ceph: Fix race between hole punch and page fault Jan Kara 2021-07-12 16:56 ` [f2fs-dev] " Jan Kara 2021-07-12 16:56 ` [PATCH 14/14] cifs: " Jan Kara 2021-07-12 16:56 ` [f2fs-dev] " Jan Kara -- strict thread matches above, loose matches on Subject: below -- 2021-07-15 13:40 [PATCH 0/14 v10] fs: Hole punch vs page cache filling races Jan Kara 2021-07-15 13:40 ` [PATCH 03/14] mm: Protect operations adding pages to page cache with invalidate_lock Jan Kara 2021-06-15 9:17 [PATCH 0/14 v8] fs: Hole punch vs page cache filling races Jan Kara 2021-06-15 9:17 ` [PATCH 03/14] mm: Protect operations adding pages to page cache with invalidate_lock Jan Kara 2021-06-16 5:33 ` Christoph Hellwig 2021-06-17 16:15 ` Darrick J. Wong 2021-06-07 14:52 [PATCH 0/14 v7] fs: Hole punch vs page cache filling races Jan Kara 2021-06-07 14:52 ` [PATCH 03/14] mm: Protect operations adding pages to page cache with invalidate_lock Jan Kara 2021-06-07 16:09 ` Darrick J. Wong 2021-06-08 12:19 ` Jan Kara
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