279d5fc322
Patch series "Add folio_end_read", v2. The core of this patchset is the new folio_end_read() call which filesystems can use when finishing a page cache read instead of separate calls to mark the folio uptodate and unlock it. As an illustration of its use, I converted ext4, iomap & mpage; more can be converted. I think that's useful by itself, but the interesting optimisation is that we can implement that with a single XOR instruction that sets the uptodate bit, clears the lock bit, tests the waiter bit and provides a write memory barrier. That removes one memory barrier and one atomic instruction from each page read, which seems worth doing. That's in patch 15. The last two patches could be a separate series, but basically we can do the same thing with the writeback flag that we do with the unlock flag; clear it and test the waiters bit at the same time. This patch (of 17): This is really preparation for the next patch, but it lets us call folio_mark_uptodate() in just one place instead of two. Link: https://lkml.kernel.org/r/20231004165317.1061855-1-willy@infradead.org Link: https://lkml.kernel.org/r/20231004165317.1061855-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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| .. | ||
| buffered-io.c | ||
| direct-io.c | ||
| fiemap.c | ||
| iter.c | ||
| Makefile | ||
| seek.c | ||
| swapfile.c | ||
| trace.c | ||
| trace.h | ||