kernel.git/mm/swap.c, branch linux-5.16.y

mm/swap.c:put_pages_list(): reinitialise the page list

2021-11-20T18:35:54Z

While free_unref_page_list() puts pages onto the CPU local LRU list, it does not remove them from the list they were passed in on. That makes the list_head appear to be non-empty, and would lead to various corruption problems if we didn't have an assertion that the list was empty. Reinitialise the list after calling free_unref_page_list() to avoid this problem. Link: https://lkml.kernel.org/r/YYp40A2lNrxaZji8@casper.infradead.org Fixes: 988c69f1bc23 ("mm: optimise put_pages_list()") Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Steve French Reported-by: Namjae Jeon Tested-by: Steve French Tested-by: Namjae Jeon Cc: Steve French Cc: Hyeoncheol Lee Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'akpm' (patches from Andrew)

2021-11-06T21:08:17Z

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 : (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 ...

mm: optimise put_pages_list()

2021-11-06T20:30:35Z

Instead of calling put_page() one page at a time, pop pages off the list if their refcount was too high and pass the remainder to put_unref_page_list(). This should be a speed improvement, but I have no measurements to support that. Current callers do not care about performance, but I hope to add some which do. Link: https://lkml.kernel.org/r/20211007192138.561673-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Anthony Yznaga Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/lru: Add folio_add_lru()

2021-10-18T11:49:40Z

Reimplement lru_cache_add() as a wrapper around folio_add_lru(). Saves 159 bytes of kernel text due to removing calls to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka

mm/lru: Convert __pagevec_lru_add_fn to take a folio

2021-10-18T11:49:40Z

This saves five calls to compound_head(), totalling 60 bytes of text. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka

mm/workingset: Convert workingset_refault() to take a folio

2021-10-18T11:49:40Z

This nets us 178 bytes of savings from removing calls to compound_head. The three callers all grow a little, but each of them will be converted to use folios soon, so that's fine. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka

mm/swap: Add folio_mark_accessed()

2021-10-18T11:49:39Z

Convert mark_page_accessed() to folio_mark_accessed(). It already operated on the entire compound page, but now we can avoid calling compound_head quite so many times. Shrinks the function from 424 bytes to 295 bytes (shrinking by 129 bytes). The compatibility wrapper is 30 bytes, plus the 8 bytes for the exported symbol means the kernel shrinks by 91 bytes. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: David Howells Acked-by: Vlastimil Babka

mm/swap: Add folio_activate()

2021-10-18T11:49:39Z

This replaces activate_page() and eliminates lots of calls to compound_head(). Saves net 118 bytes of kernel text. There are still some redundant calls to page_folio() here which will be removed when pagevec_lru_move_fn() is converted to use folios. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka

mm/workingset: Convert workingset_activation to take a folio

2021-09-27T13:27:32Z

This function already assumed it was being passed a head page. No real change here, except that thp_nr_pages() compiles away on kernels with THP compiled out while folio_nr_pages() is always present. Also convert page_memcg_rcu() to folio_memcg_rcu(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka

mm/memcg: Add folio_lruvec_relock_irq() and folio_lruvec_relock_irqsave()

2021-09-27T13:27:31Z

These are the folio equivalents of relock_page_lruvec_irq() and folio_lruvec_relock_irqsave(). Also convert page_matches_lruvec() to folio_matches_lruvec(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka