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2024-06-05mm: drop the 'anon_' prefix for swap-out mTHP countersBaolin Wang
The mTHP swap related counters: 'anon_swpout' and 'anon_swpout_fallback' are confusing with an 'anon_' prefix, since the shmem can swap out non-anonymous pages. So drop the 'anon_' prefix to keep consistent with the old swap counter names. This is needed in 6.10-rcX to avoid having an inconsistent ABI out in the field. Link: https://lkml.kernel.org/r/7a8989c13299920d7589007a30065c3e2c19f0e0.1716431702.git.baolin.wang@linux.alibaba.com Fixes: d0f048ac39f6 ("mm: add per-order mTHP anon_swpout and anon_swpout_fallback counters") Fixes: 42248b9d34ea ("mm: add docs for per-order mTHP counters and transhuge_page ABI") Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Suggested-by: "Huang, Ying" <ying.huang@intel.com> Acked-by: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm: add per-order mTHP anon_swpout and anon_swpout_fallback countersBarry Song
This helps to display the fragmentation situation of the swapfile, knowing the proportion of how much we haven't split large folios. So far, we only support non-split swapout for anon memory, with the possibility of expanding to shmem in the future. So, we add the "anon" prefix to the counter names. Link: https://lkml.kernel.org/r/20240412114858.407208-3-21cnbao@gmail.com Signed-off-by: Barry Song <v-songbaohua@oppo.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Chris Li <chrisl@kernel.org> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Kairui Song <kasong@tencent.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25arm64: mm: swap: support THP_SWAP on hardware with MTEBarry Song
Commit d0637c505f8a1 ("arm64: enable THP_SWAP for arm64") brings up THP_SWAP on ARM64, but it doesn't enable THP_SWP on hardware with MTE as the MTE code works with the assumption tags save/restore is always handling a folio with only one page. The limitation should be removed as more and more ARM64 SoCs have this feature. Co-existence of MTE and THP_SWAP becomes more and more important. This patch makes MTE tags saving support large folios, then we don't need to split large folios into base pages for swapping out on ARM64 SoCs with MTE any more. arch_prepare_to_swap() should take folio rather than page as parameter because we support THP swap-out as a whole. It saves tags for all pages in a large folio. As now we are restoring tags based-on folio, in arch_swap_restore(), we may increase some extra loops and early-exitings while refaulting a large folio which is still in swapcache in do_swap_page(). In case a large folio has nr pages, do_swap_page() will only set the PTE of the particular page which is causing the page fault. Thus do_swap_page() runs nr times, and each time, arch_swap_restore() will loop nr times for those subpages in the folio. So right now the algorithmic complexity becomes O(nr^2). Once we support mapping large folios in do_swap_page(), extra loops and early-exitings will decrease while not being completely removed as a large folio might get partially tagged in corner cases such as, 1. a large folio in swapcache can be partially unmapped, thus, MTE tags for the unmapped pages will be invalidated; 2. users might use mprotect() to set MTEs on a part of a large folio. arch_thp_swp_supported() is dropped since ARM64 MTE was the only one who needed it. Link: https://lkml.kernel.org/r/20240322114136.61386-2-21cnbao@gmail.com Signed-off-by: Barry Song <v-songbaohua@oppo.com> Reviewed-by: Steven Price <steven.price@arm.com> Acked-by: Chris Li <chrisl@kernel.org> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29zswap: memcontrol: implement zswap writeback disablingNhat Pham
During our experiment with zswap, we sometimes observe swap IOs due to occasional zswap store failures and writebacks-to-swap. These swapping IOs prevent many users who cannot tolerate swapping from adopting zswap to save memory and improve performance where possible. This patch adds the option to disable this behavior entirely: do not writeback to backing swapping device when a zswap store attempt fail, and do not write pages in the zswap pool back to the backing swap device (both when the pool is full, and when the new zswap shrinker is called). This new behavior can be opted-in/out on a per-cgroup basis via a new cgroup file. By default, writebacks to swap device is enabled, which is the previous behavior. Initially, writeback is enabled for the root cgroup, and a newly created cgroup will inherit the current setting of its parent. Note that this is subtly different from setting memory.swap.max to 0, as it still allows for pages to be stored in the zswap pool (which itself consumes swap space in its current form). This patch should be applied on top of the zswap shrinker series: https://lore.kernel.org/linux-mm/20231130194023.4102148-1-nphamcs@gmail.com/ as it also disables the zswap shrinker, a major source of zswap writebacks. For the most part, this feature is motivated by internal parties who have already established their opinions regarding swapping - the workloads that are highly sensitive to IO, and especially those who are using servers with really slow disk performance (for instance, massive but slow HDDs). For these folks, it's impossible to convince them to even entertain zswap if swapping also comes as a packaged deal. Writeback disabling is quite a useful feature in these situations - on a mixed workloads deployment, they can disable writeback for the more IO-sensitive workloads, and enable writeback for other background workloads. For instance, on a server with HDD, I allocate memories and populate them with random values (so that zswap store will always fail), and specify memory.high low enough to trigger reclaim. The time it takes to allocate the memories and just read through it a couple of times (doing silly things like computing the values' average etc.): zswap.writeback disabled: real 0m30.537s user 0m23.687s sys 0m6.637s 0 pages swapped in 0 pages swapped out zswap.writeback enabled: real 0m45.061s user 0m24.310s sys 0m8.892s 712686 pages swapped in 461093 pages swapped out (the last two lines are from vmstat -s). [nphamcs@gmail.com: add a comment about recurring zswap store failures leading to reclaim inefficiency] Link: https://lkml.kernel.org/r/20231221005725.3446672-1-nphamcs@gmail.com Link: https://lkml.kernel.org/r/20231207192406.3809579-1-nphamcs@gmail.com Signed-off-by: Nhat Pham <nphamcs@gmail.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Chris Li <chrisl@kernel.org> Cc: Dan Streetman <ddstreet@ieee.org> Cc: David Heidelberg <david@ixit.cz> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Zefan Li <lizefan.x@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: convert swap_readpage() to swap_read_folio()Matthew Wilcox (Oracle)
All callers have a folio, so pass it in, saving two calls to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-11-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: convert swap_page_sector() to swap_folio_sector()Matthew Wilcox (Oracle)
All callers have a folio, so pass it in. Saves a couple of calls to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-10-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to swap_readpage_bdev_async()Matthew Wilcox (Oracle)
Make it plain that this takes the head page (which before this point was just an assumption, but is now enforced by the compiler). Link: https://lkml.kernel.org/r/20231213215842.671461-9-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to swap_readpage_bdev_sync()Matthew Wilcox (Oracle)
Make it plain that this takes the head page (which before this point was just an assumption, but is now enforced by the compiler). Link: https://lkml.kernel.org/r/20231213215842.671461-8-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to swap_readpage_fs()Matthew Wilcox (Oracle)
Saves a call to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to swap_writepage_bdev_async()Matthew Wilcox (Oracle)
Saves a call to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-6-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to swap_writepage_bdev_sync()Matthew Wilcox (Oracle)
Saves a call to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to swap_writepage_fs()Matthew Wilcox (Oracle)
Saves several calls to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-4-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29mm: pass a folio to __swap_writepage()Matthew Wilcox (Oracle)
Both callers now have a folio, so pass that in instead of the page. Removes a few hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20231213215842.671461-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04mm: memcg: add THP swap out info for anonymous reclaimXin Hao
At present, we support per-memcg reclaim strategy, however we do not know the number of transparent huge pages being reclaimed, as we know the transparent huge pages need to be splited before reclaim them, and they will bring some performance bottleneck effect. for example, when two memcg (A & B) are doing reclaim for anonymous pages at same time, and 'A' memcg is reclaiming a large number of transparent huge pages, we can better analyze that the performance bottleneck will be caused by 'A' memcg. therefore, in order to better analyze such problems, there add THP swap out info for per-memcg. [akpm@linux-foundation.orgL fix swap_writepage_fs(), per Johannes] Link: https://lkml.kernel.org/r/20230913213343.GB48476@cmpxchg.org Link: https://lkml.kernel.org/r/20230913164938.16918-1-vernhao@tencent.com Signed-off-by: Xin Hao <vernhao@tencent.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeelb@google.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21zswap: make zswap_load() take a folioMatthew Wilcox (Oracle)
Only convert a few easy parts of this function to use the folio passed in; convert back to struct page for the majority of it. Removes three hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20230715042343.434588-6-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21swap: remove some calls to compound_head() in swap_readpage()Matthew Wilcox (Oracle)
Replace six implicit calls to compound_head() with one call to page_folio(). Link: https://lkml.kernel.org/r/20230715042343.434588-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21zswap: make zswap_store() take a folioMatthew Wilcox (Oracle)
Patch series "Followup folio conversions for zswap". With frontswap killed, it's worth converting the zswap_load() and zswap_store() functions to take a folio instead of a page pointer. They aren't converted to support large folios, but there are a lot of unnecessary calls to compound_head() that are removed by these patches. This patch (of 4): Only convert a few easy parts of this function to use the folio passed in; convert back to struct page for the majority of it. This does remove a few hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20230715042343.434588-1-willy@infradead.org Link: https://lkml.kernel.org/r/20230715042343.434588-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21mm: kill frontswapJohannes Weiner
The only user of frontswap is zswap, and has been for a long time. Have swap call into zswap directly and remove the indirection. [hannes@cmpxchg.org: remove obsolete comment, per Yosry] Link: https://lkml.kernel.org/r/20230719142832.GA932528@cmpxchg.org [fengwei.yin@intel.com: don't warn if none swapcache folio is passed to zswap_load] Link: https://lkml.kernel.org/r/20230810095652.3905184-1-fengwei.yin@intel.com Link: https://lkml.kernel.org/r/20230717160227.GA867137@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Yin Fengwei <fengwei.yin@intel.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Nhat Pham <nphamcs@gmail.com> Acked-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: convert bio_associate_blkg_from_page() to take in a folioZhangPeng
Convert bio_associate_blkg_from_page() to take in a folio. We can remove two implicit calls to compound_head() by taking in a folio. Link: https://lkml.kernel.org/r/20230721034451.16412-11-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: convert count_swpout_vm_event() to take in a folioZhangPeng
Convert count_swpout_vm_event() to take in a folio. We can remove five implicit calls to compound_head() by taking in a folio. Link: https://lkml.kernel.org/r/20230721034451.16412-10-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: use a folio in swap_writepage_bdev_async()ZhangPeng
Saves one implicit call to compound_head(). Link: https://lkml.kernel.org/r/20230721034451.16412-9-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: use a folio in swap_writepage_bdev_sync()ZhangPeng
Saves one implicit call to compound_head(). Link: https://lkml.kernel.org/r/20230721034451.16412-8-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: use a folio in sio_read_complete()ZhangPeng
Saves one implicit call to compound_head(). Link: https://lkml.kernel.org/r/20230721034451.16412-7-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: use a folio in __end_swap_bio_read()ZhangPeng
Saves one implicit call to compound_head(). Link: https://lkml.kernel.org/r/20230721034451.16412-6-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: use a folio in __end_swap_bio_write()ZhangPeng
Saves two implicit call to compound_head(). Link: https://lkml.kernel.org/r/20230721034451.16412-5-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: remove unneeded SetPageError()ZhangPeng
Nobody checks the PageError()/folio_test_error() for the page/folio in __end_swap_bio_read/write() and sio_write_complete(). Therefore, we don't need to set the error flag. Just drop it. Link: https://lkml.kernel.org/r/20230721034451.16412-3-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm/page_io: remove unneeded ClearPageUptodate()ZhangPeng
Patch series "Convert several functions in page_io.c to use a folio", v4. Convert several functions in page_io.c to use a folio, which can remove several implicit calls to compound_head(). This patch (of 10): The VM_BUG_ON_FOLIO in swap_readpage() ensures that the page is already !uptodate in __end_swap_bio_read() and sio_read_complete(). Just remove unneeded ClearPageUptodate(). Link: https://lkml.kernel.org/r/20230721034451.16412-1-zhangpeng362@huawei.com Link: https://lkml.kernel.org/r/20230721034451.16412-2-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-05-31swap: use __bio_add_page to add page to bioJohannes Thumshirn
The swap code only adds a single page to a newly created bio. So use __bio_add_page() to add the page which is guaranteed to succeed in this case. This brings us closer to marking bio_add_page() as __must_check. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/5bdafd9de806b2dab92302b30eb7a3a5f10c37d9.1685532726.git.johannes.thumshirn@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-23Merge tag 'mm-stable-2023-02-20-13-37' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Daniel Verkamp has contributed a memfd series ("mm/memfd: add F_SEAL_EXEC") which permits the setting of the memfd execute bit at memfd creation time, with the option of sealing the state of the X bit. - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset() thread-safe for pmd unshare") which addresses a rare race condition related to PMD unsharing. - Several folioification patch serieses from Matthew Wilcox, Vishal Moola, Sidhartha Kumar and Lorenzo Stoakes - Johannes Weiner has a series ("mm: push down lock_page_memcg()") which does perform some memcg maintenance and cleanup work. - SeongJae Park has added DAMOS filtering to DAMON, with the series "mm/damon/core: implement damos filter". These filters provide users with finer-grained control over DAMOS's actions. SeongJae has also done some DAMON cleanup work. - Kairui Song adds a series ("Clean up and fixes for swap"). - Vernon Yang contributed the series "Clean up and refinement for maple tree". - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It adds to MGLRU an LRU of memcgs, to improve the scalability of global reclaim. - David Hildenbrand has added some userfaultfd cleanup work in the series "mm: uffd-wp + change_protection() cleanups". - Christoph Hellwig has removed the generic_writepages() library function in the series "remove generic_writepages". - Baolin Wang has performed some maintenance on the compaction code in his series "Some small improvements for compaction". - Sidhartha Kumar is doing some maintenance work on struct page in his series "Get rid of tail page fields". - David Hildenbrand contributed some cleanup, bugfixing and generalization of pte management and of pte debugging in his series "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap PTEs". - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation flag in the series "Discard __GFP_ATOMIC". - Sergey Senozhatsky has improved zsmalloc's memory utilization with his series "zsmalloc: make zspage chain size configurable". - Joey Gouly has added prctl() support for prohibiting the creation of writeable+executable mappings. The previous BPF-based approach had shortcomings. See "mm: In-kernel support for memory-deny-write-execute (MDWE)". - Waiman Long did some kmemleak cleanup and bugfixing in the series "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF". - T.J. Alumbaugh has contributed some MGLRU cleanup work in his series "mm: multi-gen LRU: improve". - Jiaqi Yan has provided some enhancements to our memory error statistics reporting, mainly by presenting the statistics on a per-node basis. See the series "Introduce per NUMA node memory error statistics". - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog regression in compaction via his series "Fix excessive CPU usage during compaction". - Christoph Hellwig does some vmalloc maintenance work in the series "cleanup vfree and vunmap". - Christoph Hellwig has removed block_device_operations.rw_page() in ths series "remove ->rw_page". - We get some maple_tree improvements and cleanups in Liam Howlett's series "VMA tree type safety and remove __vma_adjust()". - Suren Baghdasaryan has done some work on the maintainability of our vm_flags handling in the series "introduce vm_flags modifier functions". - Some pagemap cleanup and generalization work in Mike Rapoport's series "mm, arch: add generic implementation of pfn_valid() for FLATMEM" and "fixups for generic implementation of pfn_valid()" - Baoquan He has done some work to make /proc/vmallocinfo and /proc/kcore better represent the real state of things in his series "mm/vmalloc.c: allow vread() to read out vm_map_ram areas". - Jason Gunthorpe rationalized the GUP system's interface to the rest of the kernel in the series "Simplify the external interface for GUP". - SeongJae Park wishes to migrate people from DAMON's debugfs interface over to its sysfs interface. To support this, we'll temporarily be printing warnings when people use the debugfs interface. See the series "mm/damon: deprecate DAMON debugfs interface". - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes and clean-ups" series. - Huang Ying has provided a dramatic reduction in migration's TLB flush IPI rates with the series "migrate_pages(): batch TLB flushing". - Arnd Bergmann has some objtool fixups in "objtool warning fixes". * tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits) include/linux/migrate.h: remove unneeded externs mm/memory_hotplug: cleanup return value handing in do_migrate_range() mm/uffd: fix comment in handling pte markers mm: change to return bool for isolate_movable_page() mm: hugetlb: change to return bool for isolate_hugetlb() mm: change to return bool for isolate_lru_page() mm: change to return bool for folio_isolate_lru() objtool: add UACCESS exceptions for __tsan_volatile_read/write kmsan: disable ftrace in kmsan core code kasan: mark addr_has_metadata __always_inline mm: memcontrol: rename memcg_kmem_enabled() sh: initialize max_mapnr m68k/nommu: add missing definition of ARCH_PFN_OFFSET mm: percpu: fix incorrect size in pcpu_obj_full_size() maple_tree: reduce stack usage with gcc-9 and earlier mm: page_alloc: call panic() when memoryless node allocation fails mm: multi-gen LRU: avoid futile retries migrate_pages: move THP/hugetlb migration support check to simplify code migrate_pages: batch flushing TLB migrate_pages: share more code between _unmap and _move ...
2023-02-03swap: use bvec_set_page to initialize bvecsChristoph Hellwig
Use the bvec_set_page helper to initialize bvecs. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230203150634.3199647-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-02block: remove ->rw_pageChristoph Hellwig
The ->rw_page method is a special purpose bypass of the usual bio handling path that is limited to single-page reads and writes and synchronous which causes a lot of extra code in the drivers, callers and the block layer. The only remaining user is the MM swap code. Switch that swap code to simply submit a single-vec on-stack bio an synchronously wait on it based on a newly added QUEUE_FLAG_SYNCHRONOUS flag set by the drivers that currently implement ->rw_page instead. While this touches one extra cache line and executes extra code, it simplifies the block layer and drivers and ensures that all feastures are properly supported by all drivers, e.g. right now ->rw_page bypassed cgroup writeback entirely. [akpm@linux-foundation.org: fix comment typo, per Dan] Link: https://lkml.kernel.org/r/20230125133436.447864-8-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: factor out a swap_writepage_bdev helperChristoph Hellwig
Split the block device case from swap_readpage into a separate helper, following the abstraction for file based swap. Link: https://lkml.kernel.org/r/20230125133436.447864-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: remove the __swap_writepage return valueChristoph Hellwig
__swap_writepage always returns 0. Link: https://lkml.kernel.org/r/20230125133436.447864-6-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: use an on-stack bio for synchronous swapinChristoph Hellwig
Optimize the synchronous swap in case by using an on-stack bio instead of allocating one using bio_alloc. Link: https://lkml.kernel.org/r/20230125133436.447864-5-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: factor out a swap_readpage_bdev helperChristoph Hellwig
Split the block device case from swap_readpage into a separate helper, following the abstraction for file based swap and frontswap. Link: https://lkml.kernel.org/r/20230125133436.447864-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: remove the swap_readpage return valueChristoph Hellwig
swap_readpage always returns 0, and no caller checks the return value. [akpm@linux-foundation.org: fix void-returning swap_readpage() stub, per Keith] Link: https://lkml.kernel.org/r/20230125133436.447864-3-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18page_io: remove buffer_head includeMatthew Wilcox (Oracle)
page_io never uses buffer_heads to do I/O. Link: https://lkml.kernel.org/r/20221215214402.3522366-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-25use less confusing names for iov_iter direction initializersAl Viro
READ/WRITE proved to be actively confusing - the meanings are "data destination, as used with read(2)" and "data source, as used with write(2)", but people keep interpreting those as "we read data from it" and "we write data to it", i.e. exactly the wrong way. Call them ITER_DEST and ITER_SOURCE - at least that is harder to misinterpret... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-10-03swap: convert swap_writepage() to use a folioMatthew Wilcox (Oracle)
Removes many calls to compound_head(). Link: https://lkml.kernel.org/r/20220902194653.1739778-41-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-26mm/page_io: count submission time as thrashing delay for delayacctYang Yang
Once upon a time, we only support accounting thrashing of page cache. Then Joonsoo introduced workingset detection for anonymous pages and we gained the ability to account thrashing of them[1]. Likes PSI, we count submission time as thrashing delay because when the device is congested, or the submitting cgroup IO-throttled, submission can be a significant part of overall IO time. Without this patch, swap thrashing through frontswap or some block device supporting rw_page operation isn't measured correctly. This patch is based on "delayacct: support re-entrance detection of thrashing accounting". [1] commit aae466b0052e ("mm/swap: implement workingset detection for anonymous LRU") Link: https://lkml.kernel.org/r/20220815072835.74876-1-yang.yang29@zte.com.cn Signed-off-by: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: CGEL ZTE <cgel.zte@gmail.com> Reviewed-by: Ran Xiaokai <ran.xiaokai@zte.com.cn> Reviewed-by: wangyong <wang.yong12@zte.com.cn> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11mm/swap: remove the end_write_func argument to __swap_writepageChristoph Hellwig
The argument is always set to end_swap_bio_write, so remove the argument and mark end_swap_bio_write static. Link: https://lkml.kernel.org/r/20220811141741.660214-1-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Seth Jennings <sjenning@redhat.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-26Merge tag 'mm-stable-2022-05-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Almost all of MM here. A few things are still getting finished off, reviewed, etc. - Yang Shi has improved the behaviour of khugepaged collapsing of readonly file-backed transparent hugepages. - Johannes Weiner has arranged for zswap memory use to be tracked and managed on a per-cgroup basis. - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for runtime enablement of the recent huge page vmemmap optimization feature. - Baolin Wang contributes a series to fix some issues around hugetlb pagetable invalidation. - Zhenwei Pi has fixed some interactions between hwpoisoned pages and virtualization. - Tong Tiangen has enabled the use of the presently x86-only page_table_check debugging feature on arm64 and riscv. - David Vernet has done some fixup work on the memcg selftests. - Peter Xu has taught userfaultfd to handle write protection faults against shmem- and hugetlbfs-backed files. - More DAMON development from SeongJae Park - adding online tuning of the feature and support for monitoring of fixed virtual address ranges. Also easier discovery of which monitoring operations are available. - Nadav Amit has done some optimization of TLB flushing during mprotect(). - Neil Brown continues to labor away at improving our swap-over-NFS support. - David Hildenbrand has some fixes to anon page COWing versus get_user_pages(). - Peng Liu fixed some errors in the core hugetlb code. - Joao Martins has reduced the amount of memory consumed by device-dax's compound devmaps. - Some cleanups of the arch-specific pagemap code from Anshuman Khandual. - Muchun Song has found and fixed some errors in the TLB flushing of transparent hugepages. - Roman Gushchin has done more work on the memcg selftests. ... and, of course, many smaller fixes and cleanups. Notably, the customary million cleanup serieses from Miaohe Lin" * tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits) mm: kfence: use PAGE_ALIGNED helper selftests: vm: add the "settings" file with timeout variable selftests: vm: add "test_hmm.sh" to TEST_FILES selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests selftests: vm: add migration to the .gitignore selftests/vm/pkeys: fix typo in comment ksm: fix typo in comment selftests: vm: add process_mrelease tests Revert "mm/vmscan: never demote for memcg reclaim" mm/kfence: print disabling or re-enabling message include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace" include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion" mm: fix a potential infinite loop in start_isolate_page_range() MAINTAINERS: add Muchun as co-maintainer for HugeTLB zram: fix Kconfig dependency warning mm/shmem: fix shmem folio swapoff hang cgroup: fix an error handling path in alloc_pagecache_max_30M() mm: damon: use HPAGE_PMD_SIZE tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate nodemask.h: fix compilation error with GCC12 ...
2022-05-24Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds
Pull page cache updates from Matthew Wilcox: - Appoint myself page cache maintainer - Fix how scsicam uses the page cache - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS - Remove the AOP flags entirely - Remove pagecache_write_begin() and pagecache_write_end() - Documentation updates - Convert several address_space operations to use folios: - is_dirty_writeback - readpage becomes read_folio - releasepage becomes release_folio - freepage becomes free_folio - Change filler_t to require a struct file pointer be the first argument like ->read_folio * tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits) nilfs2: Fix some kernel-doc comments Appoint myself page cache maintainer fs: Remove aops->freepage secretmem: Convert to free_folio nfs: Convert to free_folio orangefs: Convert to free_folio fs: Add free_folio address space operation fs: Convert drop_buffers() to use a folio fs: Change try_to_free_buffers() to take a folio jbd2: Convert release_buffer_page() to use a folio jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio reiserfs: Convert release_buffer_page() to use a folio fs: Remove last vestiges of releasepage ubifs: Convert to release_folio reiserfs: Convert to release_folio orangefs: Convert to release_folio ocfs2: Convert to release_folio nilfs2: Remove comment about releasepage nfs: Convert to release_folio jfs: Convert to release_folio ...
2022-05-09MM: handle THP in swap_*page_fs() - count_vm_events()NeilBrown
We need to use count_swpout_vm_event() for sio_write_complete() to get correct counting. Note that THP swap in (if it ever happens) is current accounted 1 for each page, whether HUGE or normal. This is different from swap-out accounting. This patch should be squashed into MM: handle THP in swap_*page_fs() Link: https://lkml.kernel.org/r/165146948934.24404.5909750610552745025@noble.neil.brown.name Signed-off-by: NeilBrown <neilb@suse.de> Reported-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Yang Shi <shy828301@gmail.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09mm: handle THP in swap_*page_fs()NeilBrown
Pages passed to swap_readpage()/swap_writepage() are not necessarily all the same size - there may be transparent-huge-pages involves. The BIO paths of swap_*page() handle this correctly, but the SWP_FS_OPS path does not. So we need to use thp_size() to find the size, not just assume PAGE_SIZE, and we need to track the total length of the request, not just assume it is "page * PAGE_SIZE". Link: https://lkml.kernel.org/r/165119301488.15698.9457662928942765453.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reported-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09mm: submit multipage write for SWP_FS_OPS swap-spaceNeilBrown
swap_writepage() is given one page at a time, but may be called repeatedly in succession. For block-device swapspace, the blk_plug functionality allows the multiple pages to be combined together at lower layers. That cannot be used for SWP_FS_OPS as blk_plug may not exist - it is only active when CONFIG_BLOCK=y. Consequently all swap reads over NFS are single page reads. With this patch we pass a pointer-to-pointer via the wbc. swap_writepage can store state between calls - much like the pointer passed explicitly to swap_readpage. After calling swap_writepage() some number of times, the state will be passed to swap_write_unplug() which can submit the combined request. Link: https://lkml.kernel.org/r/164859778128.29473.5191868522654408537.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09mm: submit multipage reads for SWP_FS_OPS swap-spaceNeilBrown
swap_readpage() is given one page at a time, but may be called repeatedly in succession. For block-device swap-space, the blk_plug functionality allows the multiple pages to be combined together at lower layers. That cannot be used for SWP_FS_OPS as blk_plug may not exist - it is only active when CONFIG_BLOCK=y. Consequently all swap reads over NFS are single page reads. With this patch we pass in a pointer-to-pointer when swap_readpage can store state between calls - much like the effect of blk_plug. After calling swap_readpage() some number of times, the state will be passed to swap_read_unplug() which can submit the combined request. Link: https://lkml.kernel.org/r/164859778127.29473.14059420492644907783.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09mm: perform async writes to SWP_FS_OPS swap-space using ->swap_rwNeilBrown
This patch switches swap-out to SWP_FS_OPS swap-spaces to use ->swap_rw and makes the writes asynchronous, like they are for other swap spaces. To make it async we need to allocate the kiocb struct from a mempool. This may block, but won't block as long as waiting for the write to complete. At most it will wait for some previous swap IO to complete. Link: https://lkml.kernel.org/r/164859778126.29473.12399585304843922231.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09mm: introduce ->swap_rw and use it for reads from SWP_FS_OPS swap-spaceNeilBrown
swap currently uses ->readpage to read swap pages. This can only request one page at a time from the filesystem, which is not most efficient. swap uses ->direct_IO for writes which while this is adequate is an inappropriate over-loading. ->direct_IO may need to had handle allocate space for holes or other details that are not relevant for swap. So this patch introduces a new address_space operation: ->swap_rw. In this patch it is used for reads, and a subsequent patch will switch writes to use it. No filesystem yet supports ->swap_rw, but that is not a problem because no filesystem actually works with filesystem-based swap. Only two filesystems set SWP_FS_OPS: - cifs sets the flag, but ->direct_IO always fails so swap cannot work. - nfs sets the flag, but ->direct_IO calls generic_write_checks() which has failed on swap files for several releases. To ensure that a NULL ->swap_rw isn't called, ->activate_swap() for both NFS and cifs are changed to fail if ->swap_rw is not set. This can be removed if/when the function is added. Future patches will restore swap-over-NFS functionality. To submit an async read with ->swap_rw() we need to allocate a structure to hold the kiocb and other details. swap_readpage() cannot handle transient failure, so we create a mempool to provide the structures. Link: https://lkml.kernel.org/r/164859778125.29473.13430559328221330589.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09mm: drop swap_dirty_folioNeilBrown
folios that are written to swap are owned by the MM subsystem - not any filesystem. When such a folio is passed to a filesystem to be written out to a swap-file, the filesystem handles the data, but the folio itself does not belong to the filesystem. So calling the filesystem's ->dirty_folio() address_space operation makes no sense. This is for folios in the given address space, and a folio to be written to swap does not exist in the given address space. So drop swap_dirty_folio() which calls the address-space's ->dirty_folio(), and always use noop_dirty_folio(), which is appropriate for folios being swapped out. Link: https://lkml.kernel.org/r/164859778123.29473.6900942583784889976.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>