From: Jens Axboe axboe@kernel.dk
commit e6c8aa9ac33bd7c968af7816240fc081401fddcd upstream.
This allows us to selectively flush out pending overflows, depending on the task and/or files_struct being passed in.
No intended functional changes in this patch.
Reviewed-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/io_uring.c | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-)
--- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1344,12 +1344,24 @@ static void io_cqring_mark_overflow(stru } }
+static inline bool io_match_files(struct io_kiocb *req, + struct files_struct *files) +{ + if (!files) + return true; + if (req->flags & REQ_F_WORK_INITIALIZED) + return req->work.files == files; + return false; +} + /* Returns true if there are no backlogged entries after the flush */ -static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) +static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force, + struct task_struct *tsk, + struct files_struct *files) { struct io_rings *rings = ctx->rings; + struct io_kiocb *req, *tmp; struct io_uring_cqe *cqe; - struct io_kiocb *req; unsigned long flags; LIST_HEAD(list);
@@ -1368,13 +1380,16 @@ static bool io_cqring_overflow_flush(str ctx->cq_overflow_flushed = 1;
cqe = NULL; - while (!list_empty(&ctx->cq_overflow_list)) { + list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) { + if (tsk && req->task != tsk) + continue; + if (!io_match_files(req, files)) + continue; + cqe = io_get_cqring(ctx); if (!cqe && !force) break;
- req = list_first_entry(&ctx->cq_overflow_list, struct io_kiocb, - compl.list); list_move(&req->compl.list, &list); if (cqe) { WRITE_ONCE(cqe->user_data, req->user_data); @@ -1988,7 +2003,7 @@ static unsigned io_cqring_events(struct if (noflush && !list_empty(&ctx->cq_overflow_list)) return -1U;
- io_cqring_overflow_flush(ctx, false); + io_cqring_overflow_flush(ctx, false, NULL, NULL); }
/* See comment at the top of this file */ @@ -6489,7 +6504,7 @@ static int io_submit_sqes(struct io_ring /* if we have a backlog and couldn't flush it all, return BUSY */ if (test_bit(0, &ctx->sq_check_overflow)) { if (!list_empty(&ctx->cq_overflow_list) && - !io_cqring_overflow_flush(ctx, false)) + !io_cqring_overflow_flush(ctx, false, NULL, NULL)) return -EBUSY; }
@@ -7993,7 +8008,7 @@ static void io_ring_exit_work(struct wor */ do { if (ctx->rings) - io_cqring_overflow_flush(ctx, true); + io_cqring_overflow_flush(ctx, true, NULL, NULL); io_iopoll_try_reap_events(ctx); } while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20)); io_ring_ctx_free(ctx); @@ -8013,7 +8028,7 @@ static void io_ring_ctx_wait_and_kill(st
/* if we failed setting up the ctx, we might not have any rings */ if (ctx->rings) - io_cqring_overflow_flush(ctx, true); + io_cqring_overflow_flush(ctx, true, NULL, NULL); io_iopoll_try_reap_events(ctx); idr_for_each(&ctx->personality_idr, io_remove_personalities, ctx);
@@ -8069,12 +8084,6 @@ static bool io_match_link(struct io_kioc return false; }
-static inline bool io_match_files(struct io_kiocb *req, - struct files_struct *files) -{ - return (req->flags & REQ_F_WORK_INITIALIZED) && req->work.files == files; -} - static bool io_match_link_files(struct io_kiocb *req, struct files_struct *files) { @@ -8365,7 +8374,7 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned ret = 0; if (ctx->flags & IORING_SETUP_SQPOLL) { if (!list_empty_careful(&ctx->cq_overflow_list)) - io_cqring_overflow_flush(ctx, false); + io_cqring_overflow_flush(ctx, false, NULL, NULL); if (flags & IORING_ENTER_SQ_WAKEUP) wake_up(&ctx->sqo_wait); submitted = to_submit;