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2021-11-06Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: "257 patches. Subsystems affected by this patch series: scripts, ocfs2, vfs, and mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache, gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools, memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm, vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram, cleanups, kfence, and damon)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits) mm/damon: remove return value from before_terminate callback mm/damon: fix a few spelling mistakes in comments and a pr_debug message mm/damon: simplify stop mechanism Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions Docs/admin-guide/mm/damon/start: simplify the content Docs/admin-guide/mm/damon/start: fix a wrong link Docs/admin-guide/mm/damon/start: fix wrong example commands mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on mm/damon: remove unnecessary variable initialization Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM) selftests/damon: support watermarks mm/damon/dbgfs: support watermarks mm/damon/schemes: activate schemes based on a watermarks mechanism tools/selftests/damon: update for regions prioritization of schemes mm/damon/dbgfs: support prioritization weights mm/damon/vaddr,paddr: support pageout prioritization mm/damon/schemes: prioritize regions within the quotas mm/damon/selftests: support schemes quotas mm/damon/dbgfs: support quotas of schemes ...
2021-11-06mm/readahead.c: fix incorrect comments for get_init_ra_sizeLin Feng
In fact, formated values returned by get_init_ra_size are not that intuitive. This patch make the comments reflect its truth. Link: https://lkml.kernel.org/r/20211019104812.135602-1-linf@wangsu.com Signed-off-by: Lin Feng <linf@wangsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-10-18mm: remove spurious blkdev.h includesChristoph Hellwig
Various files have acquired spurious includes of <linux/blkdev.h> over time. Remove them. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210920123328.1399408-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-13mm: Protect operations adding pages to page cache with invalidate_lockJan Kara
Currently, serializing operations such as page fault, read, or readahead against hole punching is rather difficult. The basic race scheme is like: fallocate(FALLOC_FL_PUNCH_HOLE) read / fault / .. truncate_inode_pages_range() <create pages in page cache here> <update fs block mapping and free blocks> Now the problem is in this way read / page fault / readahead can instantiate pages in page cache with potentially stale data (if blocks get quickly reused). Avoiding this race is not simple - page locks do not work because we want to make sure there are *no* pages in given range. inode->i_rwsem does not work because page fault happens under mmap_sem which ranks below inode->i_rwsem. Also using it for reads makes the performance for mixed read-write workloads suffer. So create a new rw_semaphore in the address_space - invalidate_lock - that protects adding of pages to page cache for page faults / reads / readahead. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2021-04-23mm: Implement readahead_control pageset expansionDavid Howells
Provide a function, readahead_expand(), that expands the set of pages specified by a readahead_control object to encompass a revised area with a proposed size and length. The proposed area must include all of the old area and may be expanded yet more by this function so that the edges align on (transparent huge) page boundaries as allocated. The expansion will be cut short if a page already exists in either of the areas being expanded into. Note that any expansion made in such a case is not rolled back. This will be used by fscache so that reads can be expanded to cache granule boundaries, thereby allowing whole granules to be stored in the cache, but there are other potential users also. Changes: v6: - Fold in a patch from Matthew Wilcox to tell the ondemand readahead algorithm about the expansion so that the next readahead starts at the right place[2]. v4: - Moved the declaration of readahead_expand() to a better place[1]. Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dave Wysochanski <dwysocha@redhat.com> Tested-By: Marc Dionne <marc.dionne@auristor.com> cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Christoph Hellwig <hch@lst.de> cc: Mike Marshall <hubcap@omnibond.com> cc: linux-mm@kvack.org cc: linux-cachefs@redhat.com cc: linux-afs@lists.infradead.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20210217161358.GM2858050@casper.infradead.org/ [1] Link: https://lore.kernel.org/r/20210407201857.3582797-4-willy@infradead.org/ [2] Link: https://lore.kernel.org/r/159974633888.2094769.8326206446358128373.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/160588479816.3465195.553952688795241765.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161118131787.1232039.4863969952441067985.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161028670.2537118.13831420617039766044.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340389201.1303470.14353807284546854878.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539530488.286939.18085961677838089157.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653789422.2770958.2108046612147345000.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789069829.6155.4295672417565512161.stgit@warthog.procyon.org.uk/ # v6
2021-04-23mm/readahead: Handle ractl nr_pages being modifiedMatthew Wilcox (Oracle)
Filesystems are not currently permitted to modify the number of pages in the ractl. An upcoming patch to add readahead_expand() changes that rule, so remove the check and resync the loop counter after every call to the filesystem. Tested-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20210420200116.3715790-1-willy@infradead.org/ Link: https://lore.kernel.org/r/20210421170923.4005574-1-willy@infradead.org/ # v2
2021-04-23mm/filemap: Pass the file_ra_state in the ractlMatthew Wilcox (Oracle)
For readahead_expand(), we need to modify the file ra_state, so pass it down by adding it to the ractl. We have to do this because it's not always the same as f_ra in the struct file that is already being passed. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dave Wysochanski <dwysocha@redhat.com> Tested-By: Marc Dionne <marc.dionne@auristor.com> Link: https://lore.kernel.org/r/20210407201857.3582797-2-willy@infradead.org/ Link: https://lore.kernel.org/r/161789067431.6155.8063840447229665720.stgit@warthog.procyon.org.uk/ # v6
2020-10-17mm: use limited read-ahead to satisfy readJens Axboe
For the case where read-ahead is disabled on the file, or if the cgroup is congested, ensure that we can at least do 1 page of read-ahead to make progress on the read in an async fashion. This could potentially be larger, but it's not needed in terms of functionality, so let's error on the side of caution as larger counts of pages may run into reclaim issues (particularly if we're congested). This makes sure we're not hitting the potentially sync ->readpage() path for IO that is marked IOCB_WAITQ, which could cause us to block. It also means we'll use the same path for IO, regardless of whether or not read-ahead happens to be disabled on the lower level device. Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reported-by: Hao_Xu <haoxu@linux.alibaba.com> [axboe: updated for new ractl API] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-16mm/readahead: pass a file_ra_state into force_page_cache_raDavid Howells
The file_ra_state being passed into page_cache_sync_readahead() was being ignored in favour of using the one embedded in the struct file. The only caller for which this makes a difference is the fsverity code if the file has been marked as POSIX_FADV_RANDOM, but it's confusing and worth fixing. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Biggers <ebiggers@google.com> Link: https://lkml.kernel.org/r/20200903140844.14194-10-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/readahead: add page_cache_sync_ra and page_cache_async_raMatthew Wilcox (Oracle)
Reimplement page_cache_sync_readahead() and page_cache_async_readahead() as wrappers around versions of the function which take a readahead_control in preparation for making do_sync_mmap_readahead() pass down an RAC struct. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Howells <dhowells@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Link: https://lkml.kernel.org/r/20200903140844.14194-8-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/readahead: pass readahead_control to force_page_cache_raDavid Howells
Reimplement force_page_cache_readahead() as a wrapper around force_page_cache_ra(). Pass the existing readahead_control from page_cache_sync_readahead(). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Biggers <ebiggers@google.com> Link: https://lkml.kernel.org/r/20200903140844.14194-7-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/readahead: make ondemand_readahead take a readahead_controlDavid Howells
Make ondemand_readahead() take a readahead_control struct in preparation for making do_sync_mmap_readahead() pass down an RAC struct. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Biggers <ebiggers@google.com> Link: https://lkml.kernel.org/r/20200903140844.14194-6-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/readahead: make do_page_cache_ra take a readahead_controlMatthew Wilcox (Oracle)
Rename __do_page_cache_readahead() to do_page_cache_ra() and call it directly from ondemand_readahead() instead of indirecting via ra_submit(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Howells <dhowells@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Link: https://lkml.kernel.org/r/20200903140844.14194-5-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/readahead: make page_cache_ra_unbounded take a readahead_controlMatthew Wilcox (Oracle)
Define it in the callers instead of in page_cache_ra_unbounded(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Howells <dhowells@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Link: https://lkml.kernel.org/r/20200903140844.14194-4-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/readahead: add DEFINE_READAHEADMatthew Wilcox (Oracle)
Patch series "Readahead patches for 5.9/5.10". These are infrastructure for both the THP patchset and for the fscache rewrite, For both pieces of infrastructure being build on top of this patchset, we want the ractl to be available higher in the call-stack. For David's work, he wants to add the 'critical page' to the ractl so that he knows which page NEEDS to be brought in from storage, and which ones are nice-to-have. We might want something similar in block storage too. It used to be simple -- the first page was the critical one, but then mmap added fault-around and so for that usecase, the middle page is the critical one. Anyway, I don't have any code to show that yet, we just know that the lowest point in the callchain where we have that information is do_sync_mmap_readahead() and so the ractl needs to start its life there. For THP, we havew the code that needs it. It's actually the apex patch to the series; the one which finally starts to allocate THPs and present them to consenting filesystems: http://git.infradead.org/users/willy/pagecache.git/commitdiff/798bcf30ab2eff278caad03a9edca74d2f8ae760 This patch (of 8): Allow for a more concise definition of a struct readahead_control. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Biggers <ebiggers@google.com> Cc: David Howells <dhowells@redhat.com> Link: https://lkml.kernel.org/r/20200903140844.14194-1-willy@infradead.org Link: https://lkml.kernel.org/r/20200903140844.14194-3-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: use memalloc_nofs_save in readahead pathMatthew Wilcox (Oracle)
Ensure that memory allocations in the readahead path do not attempt to reclaim file-backed pages, which could lead to a deadlock. It is possible, though unlikely this is the root cause of a problem observed by Cong Wang. Reported-by: Cong Wang <xiyou.wangcong@gmail.com> Suggested-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-16-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: document why we don't set PageReadaheadMatthew Wilcox (Oracle)
If the page is already in cache, we don't set PageReadahead on it. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-15-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: add page_cache_readahead_unboundedMatthew Wilcox (Oracle)
ext4 and f2fs have duplicated the guts of the readahead code so they can read past i_size. Instead, separate out the guts of the readahead code so they can call it directly. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Eric Biggers <ebiggers@google.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-14-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: move end_index check out of readahead loopMatthew Wilcox (Oracle)
By reducing nr_to_read, we can eliminate this check from inside the loop. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-13-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: add readahead address space operationMatthew Wilcox (Oracle)
This replaces ->readpages with a saner interface: - Return void instead of an ignored error code. - Page cache is already populated with locked pages when ->readahead is called. - New arguments can be passed to the implementation without changing all the filesystems that use a common helper function like mpage_readahead(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-12-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: put readahead pages in cache earlierMatthew Wilcox (Oracle)
When populating the page cache for readahead, mappings that use ->readpages must populate the page cache themselves as the pages are passed on a linked list which would normally be used for the page cache's LRU. For mappings that use ->readpage or the upcoming ->readahead method, we can put the pages into the page cache as soon as they're allocated, which solves a race between readahead and direct IO. It also lets us remove the gfp argument from read_pages(). Use the new readahead_page() API to implement the repeated calls to ->readpage(), just like most filesystems will. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-11-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: remove 'page_offset' from readahead loopMatthew Wilcox (Oracle)
Replace the page_offset variable with 'index + i'. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-10-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: rename readahead loop variable to 'i'Matthew Wilcox (Oracle)
Change the type of page_idx to unsigned long, and rename it -- it's just a loop counter, not a page index. Suggested-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-9-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: rename various 'offset' parameters to 'index'Matthew Wilcox (Oracle)
The word 'offset' is used ambiguously to mean 'byte offset within a page', 'byte offset from the start of the file' and 'page offset from the start of the file'. Use 'index' to mean 'page offset from the start of the file' throughout the readahead code. [ We should probably rename the 'pgoff_t' type to 'pgidx_t' too - Linus ] Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-8-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: use readahead_control to pass argumentsMatthew Wilcox (Oracle)
In this patch, only between __do_page_cache_readahead() and read_pages(), but it will be extended in upcoming patches. The read_pages() function becomes aops centric, as this makes the most sense by the end of the patchset. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-7-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: move readahead nr_pages check into read_pagesMatthew Wilcox (Oracle)
Simplify the callers by moving the check for nr_pages and the BUG_ON into read_pages(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-5-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: ignore return value of ->readpagesMatthew Wilcox (Oracle)
We used to assign the return value to a variable, which we then ignored. Remove the pretence of caring. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-4-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02mm: return void from various readahead functionsMatthew Wilcox (Oracle)
ondemand_readahead has two callers, neither of which use the return value. That means that both ra_submit and __do_page_cache_readahead() can return void, and we don't need to worry that a present page in the readahead window causes us to return a smaller nr_pages than we ought to have. Similarly, no caller uses the return value from force_page_cache_readahead(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-3-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-21treewide: Add SPDX license identifier for missed filesThomas Gleixner
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-05docs/core-api/mm: fix return value descriptions in mm/Mike Rapoport
Many kernel-doc comments in mm/ have the return value descriptions either misformatted or omitted at all which makes kernel-doc script unhappy: $ make V=1 htmldocs ... ./mm/util.c:36: info: Scanning doc for kstrdup ./mm/util.c:41: warning: No description found for return value of 'kstrdup' ./mm/util.c:57: info: Scanning doc for kstrdup_const ./mm/util.c:66: warning: No description found for return value of 'kstrdup_const' ./mm/util.c:75: info: Scanning doc for kstrndup ./mm/util.c:83: warning: No description found for return value of 'kstrndup' ... Fixing the formatting and adding the missing return value descriptions eliminates ~100 such warnings. Link: http://lkml.kernel.org/r/1549549644-4903-4-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.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>
2018-12-28mm/readahead.c: simplify get_next_ra_size()Gao Xiang
It's a trivial simplification for get_next_ra_size() and clear enough for humans to understand. It also fixes potential overflow if ra->size(< ra_pages) is too large. Link: http://lkml.kernel.org/r/1540707206-19649-1-git-send-email-hsiangkao@aol.com Signed-off-by: Gao Xiang <hsiangkao@aol.com> Reviewed-by: Fengguang Wu <fengguang.wu@intel.com> Reviewed-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-21mm: Convert __do_page_cache_readahead to XArrayMatthew Wilcox
This one is trivial. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21page cache: Convert hole search to XArrayMatthew Wilcox
The page cache offers the ability to search for a miss in the previous or next N locations. Rather than teach the XArray about the page cache's definition of a miss, use xas_prev() and xas_next() to search the page array. This should be more efficient as it does not have to start the lookup from the top for each index. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-09-29xarray: Replace exceptional entriesMatthew Wilcox
Introduce xarray value entries and tagged pointers to replace radix tree exceptional entries. This is a slight change in encoding to allow the use of an extra bit (we can now store BITS_PER_LONG - 1 bits in a value entry). It is also a change in emphasis; exceptional entries are intimidating and different. As the comment explains, you can choose to store values or pointers in the xarray and they are both first-class citizens. Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Josef Bacik <jbacik@fb.com>
2018-08-30vfs: implement readahead(2) using POSIX_FADV_WILLNEEDAmir Goldstein
The implementation of readahead(2) syscall is identical to that of fadvise64(POSIX_FADV_WILLNEED) with a few exceptions: 1. readahead(2) returns -EINVAL for !mapping->a_ops and fadvise64() ignores the request and returns 0. 2. fadvise64() checks for integer overflow corner case 3. fadvise64() calls the optional filesystem fadvise() file operation Unite the two implementations by calling vfs_fadvise() from readahead(2) syscall. Check the !mapping->a_ops in readahead(2) syscall to preserve documented syscall ABI behaviour. Suggested-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: d1d04ef8572b ("ovl: stack file ops") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-07-27readahead: stricter check for bdi io_pagesMarkus Stockhausen
ondemand_readahead() checks bdi->io_pages to cap the maximum pages that need to be processed. This works until the readit section. If we would do an async only readahead (async size = sync size) and target is at beginning of window we expand the pages by another get_next_ra_size() pages. Btrace for large reads shows that kernel always issues a doubled size read at the beginning of processing. Add an additional check for io_pages in the lower part of the func. The fix helps devices that hard limit bio pages and rely on proper handling of max_hw_read_sectors (e.g. older FusionIO cards). For that reason it could qualify for stable. Fixes: 9491ae4a ("mm: don't cap request size based on read-ahead setting") Cc: stable@vger.kernel.org Signed-off-by: Markus Stockhausen stockhausen@collogia.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09mm: skip readahead if the cgroup is congestedJosef Bacik
We noticed in testing we'd get pretty bad latency stalls under heavy pressure because read ahead would try to do its thing while the cgroup was under severe pressure. If we're under this much pressure we want to do as little IO as possible so we can still make progress on real work if we're a throttled cgroup, so just skip readahead if our group is under pressure. Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-01mm: split ->readpages calls to avoid non-contiguous pages listsChristoph Hellwig
That way file systems don't have to go spotting for non-contiguous pages and work around them. It also kicks off I/O earlier, allowing it to finish earlier and reduce latency. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-01mm: return an unsigned int from __do_page_cache_readaheadChristoph Hellwig
We never return an error, so switch to returning an unsigned int. Most callers already did implicit casts to an unsigned type, and the one that didn't can be simplified now. Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-01mm: give the 'ret' variable a better name __do_page_cache_readaheadChristoph Hellwig
It counts the number of pages acted on, so name it nr_pages to make that obvious. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-11page cache: use xa_lockMatthew Wilcox
Remove the address_space ->tree_lock and use the xa_lock newly added to the radix_tree_root. Rename the address_space ->page_tree to ->i_pages, since we don't really care that it's a tree. [willy@infradead.org: fix nds32, fs/dax.c] Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Jeff Layton <jlayton@redhat.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-02mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()Dominik Brodowski
Using this helper allows us to avoid the in-kernel calls to the sys_readahead() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_readahead(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm@kvack.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2016-12-12mm: don't cap request size based on read-ahead settingJens Axboe
We ran into a funky issue, where someone doing 256K buffered reads saw 128K requests at the device level. Turns out it is read-ahead capping the request size, since we use 128K as the default setting. This doesn't make a lot of sense - if someone is issuing 256K reads, they should see 256K reads, regardless of the read-ahead setting, if the underlying device can support a 256K read in a single command. This patch introduces a bdi hint, io_pages. This is the soft max IO size for the lower level, I've hooked it up to the bdev settings here. Read-ahead is modified to issue the maximum of the user request size, and the read-ahead max size, but capped to the max request size on the device side. The latter is done to avoid reading ahead too much, if the application asks for a huge read. With this patch, the kernel behaves like the application expects. Link: http://lkml.kernel.org/r/1479498073-8657-1-git-send-email-axboe@fb.com Signed-off-by: Jens Axboe <axboe@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-26mm: silently skip readahead for DAX inodesRoss Zwisler
For DAX inodes we need to be careful to never have page cache pages in the mapping->page_tree. This radix tree should be composed only of DAX exceptional entries and zero pages. ltp's readahead02 test was triggering a warning because we were trying to insert a DAX exceptional entry but found that a page cache page had already been inserted into the tree. This page was being inserted into the radix tree in response to a readahead(2) call. Readahead doesn't make sense for DAX inodes, but we don't want it to report a failure either. Instead, we just return success and don't do any work. Link: http://lkml.kernel.org/r/20160824221429.21158-1-ross.zwisler@linux.intel.com Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reported-by: Jeff Moyer <jmoyer@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jan Kara <jack@suse.com> Cc: <stable@vger.kernel.org> [4.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26mm, memcg: use consistent gfp flags during readaheadMichal Hocko
Vladimir has noticed that we might declare memcg oom even during readahead because read_pages only uses GFP_KERNEL (with mapping_gfp restriction) while __do_page_cache_readahead uses page_cache_alloc_readahead which adds __GFP_NORETRY to prevent from OOMs. This gfp mask discrepancy is really unfortunate and easily fixable. Drop page_cache_alloc_readahead() which only has one user and outsource the gfp_mask logic into readahead_gfp_mask and propagate this mask from __do_page_cache_readahead down to read_pages. This alone would have only very limited impact as most filesystems are implementing ->readpages and the common implementation mpage_readpages does GFP_KERNEL (with mapping_gfp restriction) again. We can tell it to use readahead_gfp_mask instead as this function is called only during readahead as well. The same applies to read_cache_pages. ext4 has its own ext4_mpage_readpages but the path which has pages != NULL can use the same gfp mask. Btrfs, cifs, f2fs and orangefs are doing a very similar pattern to mpage_readpages so the same can be applied to them as well. [akpm@linux-foundation.org: coding-style fixes] [mhocko@suse.com: restrict gfp mask in mpage_alloc] Link: http://lkml.kernel.org/r/20160610074223.GC32285@dhcp22.suse.cz Link: http://lkml.kernel.org/r/1465301556-26431-1-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Chris Mason <clm@fb.com> Cc: Steve French <sfrench@samba.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Jan Kara <jack@suse.cz> Cc: Mike Marshall <hubcap@omnibond.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Changman Lee <cm224.lee@samsung.com> Cc: Chao Yu <yuchao0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14mm: move lru_to_page to mm_inline.hGeliang Tang
Move lru_to_page() from internal.h to mm_inline.h. Signed-off-by: Geliang Tang <geliangtang@163.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14mm/readahead.c, mm/vmscan.c: use lru_to_page instead of list_to_pageGeliang Tang
list_to_page() in readahead.c is the same as lru_to_page() in vmscan.c. So I move lru_to_page to internal.h and drop list_to_page(). Signed-off-by: Geliang Tang <geliangtang@163.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06mm, fs: introduce mapping_gfp_constraint()Michal Hocko
There are many places which use mapping_gfp_mask to restrict a more generic gfp mask which would be used for allocations which are not directly related to the page cache but they are performed in the same context. Let's introduce a helper function which makes the restriction explicit and easier to track. This patch doesn't introduce any functional changes. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michal Hocko <mhocko@suse.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm: use only per-device readahead limitRoman Gushchin
Maximal readahead size is limited now by two values: 1) by global 2Mb constant (MAX_READAHEAD in max_sane_readahead()) 2) by configurable per-device value* (bdi->ra_pages) There are devices, which require custom readahead limit. For instance, for RAIDs it's calculated as number of devices multiplied by chunk size times 2. Readahead size can never be larger than bdi->ra_pages * 2 value (POSIX_FADV_SEQUNTIAL doubles readahead size). If so, why do we need two limits? I suggest to completely remove this max_sane_readahead() stuff and use per-device readahead limit everywhere. Also, using right readahead size for RAID disks can significantly increase i/o performance: before: dd if=/dev/md2 of=/dev/null bs=100M count=100 100+0 records in 100+0 records out 10485760000 bytes (10 GB) copied, 12.9741 s, 808 MB/s after: $ dd if=/dev/md2 of=/dev/null bs=100M count=100 100+0 records in 100+0 records out 10485760000 bytes (10 GB) copied, 8.91317 s, 1.2 GB/s (It's an 8-disks RAID5 storage). This patch doesn't change sys_readahead and madvise(MADV_WILLNEED) behavior introduced by 6d2be915e589b58 ("mm/readahead.c: fix readahead failure for memoryless NUMA nodes and limit readahead pages"). Signed-off-by: Roman Gushchin <klamm@yandex-team.ru> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: onstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>