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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Mike Snitzer , Jens Axboe , Ritesh Harjani , Chuck Lever Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-mm@kvack.org, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=3145; i=jlayton@kernel.org; h=from:subject:message-id; bh=hUj4YFzyO1VXcjqqW/XO6RlSLO5yLEQJ7wt0RMQ7kic=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBp+j4ut1McCVLFPCo4dnsOZJGkCnEndrsyYF/ov 9xNqF5D4CGJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCafo+LgAKCRAADmhBGVaC FSXyD/9Ab7U6obJOZVWw7dNHbbxmdELBm7YXZHN+bn0wBFwoMj8LnuLVgv9qzU6BB1iH8cwjSxw uIooxJ++hQh8paEqfZJxOb0wGg/SvhljFvg3ClKT5twqy0/uf+MBunz8MMiNgZGEYns+m/Ip2QG FIBVdQ9Jwavv7s7XffR0Z4I30uo0TIYNgA+iE+MC9YAQBF3Jldv+uWLtJNK/VI0a33x95PSH08r 3yzXhSP+9zm/2TKeow2JnqwoKMeXCSoRsAujGJ8HWjSVeavOkFp1tgWhF8hildAohpnYVOd8zG8 nEeHwA8noNTnO4s5VltTqf5P2FkPZBzOvW1Xe+1Ecxt/NSQdMGQ3T/wUdOeZeSQhHveJ6JktJV6 LrvHxfsS738cNfr+gM/6FbPd4l4TNgdJlOzsQkybiRhj/62/3i+x9DrEl1uy6d0wa1o3SrOFnKP nK4Jb/6tJzpueCWu7NwafB8lI/S8l9ZXeFzPi/Qg/baSVF4yavGKIXI0tFnAz/cb3zp+lCyZXni ifs0gDEz1lH0n4r/yrx2xbFy+zXKu3FaXT347PWK+F3zwOQq4PodXAVLXce7YyNR3zL7LdbI3TD in1EB020peBLAmtzhm+CyNWNOTpGjPfahPjO0pD8XRHBwbyakYeNigDU1b/T//hUzln2NxpQzTR fJIV5ho33fvdWdg== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 X-Rspam-User: X-Rspamd-Queue-Id: 560F312000B X-Rspamd-Server: rspam04 X-Stat-Signature: 5m8oteidck7jtjq4s9u5ag1m5maq6dnk X-HE-Tag: 1778007611-71089 X-HE-Meta: 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 fYa5/VWR thafsGPzLptwCmtvTXsEq4O1NMUl7s8tf2DZuzYW0Lhfu6c3JZkrLEF0Y/e1W087Y5oKE5x0I7L7uqtILOuouJbhKRs5Og3gNRi+K+J9BavNNFXcAtpO+jkB1Y+Csy/jyGWYcYF6MiA9obdTTn1Og49kT5kd5RdXzNdkayVJ3wOFBx2i8P8JtrG9XR2gw2rodAdl+iMT1NKP1vMQcs+ooKCQ1krNeblujuVFgmzuv6Kee1r3p0BfVxcWny99d3vHFma37fW3tL94imSm6Po6d7iyU+PaTAIWCfdIG2lXYPKgi2dsvKmmxB46B1pcIPHvmqdtPKdrzu5yayUPSgrJyWHj/9Pl7YHRNor57zMlDpb6xVBY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: This patch series is intended to improve write performance with RWF_DONTCACHE. After sending v5 yesterday, I decided to check what Sasiko thought about this series, and lo and behold it had found a number of bugs that I had missed before. This set should fix them. Performance is identical to the v5 set. Because there are some substantive changes in this set, I've dropped the R-b's. Please resend them if you're OK with this version. Christian, please consider these for v7.2. Thanks, Signed-off-by: Jeff Layton --- Changes in v6: - Use atomic folio_test_clear_dropbehind() in __filemap_get_folio_mpol() to prevent double-decrement of WB_DONTCACHE_DIRTY by concurrent readers - Add mapping_can_writeback() guard before decrementing WB_DONTCACHE_DIRTY in __filemap_get_folio_mpol() to match the increment path - Use wb_stat_sum() instead of wb_stat() in wb_check_start_dontcache() so small writes below the percpu batch threshold are visible to the flusher - Use test_and_clear_bit for WB_start_dontcache before starting writeback to prevent lost wakeups from concurrent DONTCACHE writers - Move wb_wakeup() outside the unlocked_inode_to_wb_begin/end section in filemap_dontcache_kick_writeback() to avoid spin_unlock_irq() re-enabling interrupts while the i_pages xa_lock is held during cgroup writeback switch - Drop Reviewed-by tags due to substantive changes - Link to v5: https://lore.kernel.org/r/20260504-dontcache-v5-0-4103e58bb377@kernel.org Changes in v5: - Flesh out comment over filemap_dontcache_kick_writeback() - Drop testcases from posting - Link to v4: https://lore.kernel.org/r/20260501-dontcache-v4-0-5d5e6dc71cb3@kernel.org Changes in v4: - Track DONTCACHE dirty pages per bdi_writeback - New benchmark for competing buffered and dontcache writers - New benchmark replicating Jens' original 32 concurrent writer test - Link to v3: https://lore.kernel.org/r/20260426-dontcache-v3-0-79eb37da9547@kernel.org Changes in v3: - Track dirty DONTCACHE pages in the VM - Have flusher write back a proportional number of pages after DONTCACHE write - Link to v2: https://lore.kernel.org/r/20260408-dontcache-v2-0-948dec1e756b@kernel.org Changes in v2: - kick flusher thread instead of initiating writeback inline - add mechanism to run 'perf lock' around the testcases - Link to v1: https://lore.kernel.org/r/20260401-dontcache-v1-0-1f5746fab47a@kernel.org --- Jeff Layton (2): mm: track DONTCACHE dirty pages per bdi_writeback mm: kick writeback flusher for IOCB_DONTCACHE with targeted dirty tracking fs/fs-writeback.c | 59 ++++++++++++++++++++++++++++++++++++++++ include/linux/backing-dev-defs.h | 3 ++ include/linux/fs.h | 6 ++-- include/trace/events/writeback.h | 3 +- mm/filemap.c | 15 ++++++++-- mm/page-writeback.c | 6 ++++ 6 files changed, 85 insertions(+), 7 deletions(-) --- base-commit: 7e2326f4275c11652e1fdaae11de06159fef1d90 change-id: 20260401-dontcache-5811efd7eaf3 Best regards, -- Jeff Layton