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| author | Joseph Qi <joseph.qi@linux.alibaba.com> | 2020-09-29 09:01:22 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-09-30 20:32:34 -0600 |
| commit | dbbe9c642411c359ad0a0e32442eb2e11d3811b5 (patch) | |
| tree | e567ae2471c72402ba352b4b3383995bbdd259ae /fs/io_uring.c | |
| parent | af9c1a44f8dee7a958e07977f24ba40e3c770987 (diff) | |
| download | lwn-dbbe9c642411c359ad0a0e32442eb2e11d3811b5.tar.gz lwn-dbbe9c642411c359ad0a0e32442eb2e11d3811b5.zip | |
io_uring: show sqthread pid and cpu in fdinfo
In most cases we'll specify IORING_SETUP_SQPOLL and run multiple
io_uring instances in a host. Since all sqthreads are named
"io_uring-sq", it's hard to distinguish the relations between
application process and its io_uring sqthread.
With this patch, application can get its corresponding sqthread pid
and cpu through show_fdinfo.
Steps:
1. Get io_uring fd first.
$ ls -l /proc/<pid>/fd | grep -w io_uring
2. Then get io_uring instance related info, including corresponding
sqthread pid and cpu.
$ cat /proc/<pid>/fdinfo/<io_uring_fd>
pos: 0
flags: 02000002
mnt_id: 13
SqThread: 6929
SqThreadCpu: 2
UserFiles: 1
0: testfile
UserBufs: 0
PollList:
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
[axboe: fixed for new shared SQPOLL]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index b7a3e7c7f7bf..fcb4e95cb88d 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -9124,6 +9124,7 @@ static int io_uring_show_cred(int id, void *p, void *data) static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) { + struct io_sq_data *sq = NULL; bool has_lock; int i; @@ -9135,6 +9136,11 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) */ has_lock = mutex_trylock(&ctx->uring_lock); + if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) + sq = ctx->sq_data; + + seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1); + seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1); seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files); for (i = 0; has_lock && i < ctx->nr_user_files; i++) { struct fixed_file_table *table; |