summaryrefslogtreecommitdiff
path: root/fs/io-wq.h
diff options
context:
space:
mode:
authorJens Axboe <axboe@kernel.dk>2019-11-20 13:05:32 -0700
committerJens Axboe <axboe@kernel.dk>2019-11-25 19:56:10 -0700
commitb76da70fc3759df13e0991706451f1a2e06ba19e (patch)
treed4524d43a2ed92ccfec694ab2db3807a8985ef88 /fs/io-wq.h
parent4d7dd462971405c65bfb3821dbb6b9ce13b5e8d6 (diff)
downloadlinux-sh-b76da70fc3759df13e0991706451f1a2e06ba19e.tar.gz
io_uring: close lookup gap for dependent next work
When we find new work to process within the work handler, we queue the linked timeout before we have issued the new work. This can be problematic for very short timeouts, as we have a window where the new work isn't visible. Allow the work handler to store a callback function for this in the work item, and flag it with IO_WQ_WORK_CB if the caller has done so. If that is set, then io-wq will call the callback when it has setup the new work item. Reported-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io-wq.h')
-rw-r--r--fs/io-wq.h6
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/io-wq.h b/fs/io-wq.h
index 4b29f922f80c..b68b11bf3633 100644
--- a/fs/io-wq.h
+++ b/fs/io-wq.h
@@ -11,6 +11,7 @@ enum {
IO_WQ_WORK_NEEDS_FILES = 16,
IO_WQ_WORK_UNBOUND = 32,
IO_WQ_WORK_INTERNAL = 64,
+ IO_WQ_WORK_CB = 128,
IO_WQ_HASH_SHIFT = 24, /* upper 8 bits are used for hash key */
};
@@ -22,7 +23,10 @@ enum io_wq_cancel {
};
struct io_wq_work {
- struct list_head list;
+ union {
+ struct list_head list;
+ void *data;
+ };
void (*func)(struct io_wq_work **);
unsigned flags;
struct files_struct *files;