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| author | Pavel Begunkov <asml.silence@gmail.com> | 2021-05-16 22:58:08 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-06-14 08:23:05 -0600 |
| commit | a566c5562d41b99f11c8224b2a3010e60ad93acf (patch) | |
| tree | 3c1ba9595f5e2e848344e1d43a348366bc7000de /fs/io_uring.c | |
| parent | b13a8918d395554ff9a8cee17d03ed45d805df24 (diff) | |
| download | lwn-a566c5562d41b99f11c8224b2a3010e60ad93acf.tar.gz lwn-a566c5562d41b99f11c8224b2a3010e60ad93acf.zip | |
io_uring: remove dependency on ring->sq/cq_entries
We have numbers of {sq,cq} entries cached in ctx, don't look up them in
user-shared rings as 1) it may fetch additional cacheline 2) user may
change it and so it's always error prone.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/745d31bc2da41283ddd0489ef784af5c8d6310e9.1621201931.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index f628af3a3368..169e95126acf 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1356,7 +1356,7 @@ static inline bool io_sqring_full(struct io_ring_ctx *ctx) { struct io_rings *r = ctx->rings; - return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == r->sq_ring_entries; + return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries; } static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx) @@ -1374,7 +1374,7 @@ static inline struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx) * control dependency is enough as we're using WRITE_ONCE to * fill the cq entry */ - if (__io_cqring_events(ctx) == rings->cq_ring_entries) + if (__io_cqring_events(ctx) == ctx->cq_entries) return NULL; tail = ctx->cached_cq_tail++; @@ -1427,11 +1427,10 @@ static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx) /* Returns true if there are no backlogged entries after the flush */ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) { - struct io_rings *rings = ctx->rings; unsigned long flags; bool all_flushed, posted; - if (!force && __io_cqring_events(ctx) == rings->cq_ring_entries) + if (!force && __io_cqring_events(ctx) == ctx->cq_entries) return false; posted = false; |