public/qemu
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

block/io_uring: convert to blk_io_plug_call() API

Browse source 
Stop using the .bdrv_co_io_plug() API because it is not multi-queue
block layer friendly. Use the new blk_io_plug_call() API to batch I/O
submission instead.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20230530180959.1108766-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2023-05-30 14:09:57 -04:00
parent 28ff7b4dfb
commit 6a6da231b7
4 changed files with 19 additions and 47 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
block/file-posix.c
View file

@ -2558,11 +2558,6 @@ static void coroutine_fn raw_co_io_plug(BlockDriverState *bs)
laio_io_plug();
}
#endif
#ifdef CONFIG_LINUX_IO_URING
if (s->use_linux_io_uring) {
luring_io_plug();
}
#endif
}
static void coroutine_fn raw_co_io_unplug(BlockDriverState *bs)
@ -2573,11 +2568,6 @@ static void coroutine_fn raw_co_io_unplug(BlockDriverState *bs)
laio_io_unplug(s->aio_max_batch);
}
#endif
#ifdef CONFIG_LINUX_IO_URING
if (s->use_linux_io_uring) {
luring_io_unplug();
}
#endif
}
static int coroutine_fn raw_co_flush_to_disk(BlockDriverState *bs)

44
block/io_uring.c
View file

@ -16,6 +16,7 @@
#include "block/raw-aio.h"
#include "qemu/coroutine.h"
#include "qapi/error.h"
#include "sysemu/block-backend.h"
#include "trace.h"
/* Only used for assertions. */
@ -41,7 +42,6 @@ typedef struct LuringAIOCB {
} LuringAIOCB;
typedef struct LuringQueue {
int plugged;
unsigned int in_queue;
unsigned int in_flight;
bool blocked;
@ -267,7 +267,7 @@ static void luring_process_completions_and_submit(LuringState *s)
{
luring_process_completions(s);
if (!s->io_q.plugged && s->io_q.in_queue > 0) {
if (s->io_q.in_queue > 0) {
ioq_submit(s);
}
}
@ -301,29 +301,17 @@ static void qemu_luring_poll_ready(void *opaque)
static void ioq_init(LuringQueue *io_q)
{
QSIMPLEQ_INIT(&io_q->submit_queue);
io_q->plugged = 0;
io_q->in_queue = 0;
io_q->in_flight = 0;
io_q->blocked = false;
}
void luring_io_plug(void)
static void luring_unplug_fn(void *opaque)
{
AioContext *ctx = qemu_get_current_aio_context();
LuringState *s = aio_get_linux_io_uring(ctx);
trace_luring_io_plug(s);
s->io_q.plugged++;
}
void luring_io_unplug(void)
{
AioContext *ctx = qemu_get_current_aio_context();
LuringState *s = aio_get_linux_io_uring(ctx);
assert(s->io_q.plugged);
trace_luring_io_unplug(s, s->io_q.blocked, s->io_q.plugged,
s->io_q.in_queue, s->io_q.in_flight);
if (--s->io_q.plugged == 0 &&
!s->io_q.blocked && s->io_q.in_queue > 0) {
LuringState *s = opaque;
trace_luring_unplug_fn(s, s->io_q.blocked, s->io_q.in_queue,
s->io_q.in_flight);
if (!s->io_q.blocked && s->io_q.in_queue > 0) {
ioq_submit(s);
}
}
@ -370,14 +358,16 @@ static int luring_do_submit(int fd, LuringAIOCB *luringcb, LuringState *s,
QSIMPLEQ_INSERT_TAIL(&s->io_q.submit_queue, luringcb, next);
s->io_q.in_queue++;
trace_luring_do_submit(s, s->io_q.blocked, s->io_q.plugged,
s->io_q.in_queue, s->io_q.in_flight);
if (!s->io_q.blocked &&
(!s->io_q.plugged ||
s->io_q.in_flight + s->io_q.in_queue >= MAX_ENTRIES)) {
ret = ioq_submit(s);
trace_luring_do_submit_done(s, ret);
return ret;
trace_luring_do_submit(s, s->io_q.blocked, s->io_q.in_queue,
s->io_q.in_flight);
if (!s->io_q.blocked) {
if (s->io_q.in_flight + s->io_q.in_queue >= MAX_ENTRIES) {
ret = ioq_submit(s);
trace_luring_do_submit_done(s, ret);
return ret;
}
blk_io_plug_call(luring_unplug_fn, s);
}
return 0;
}

5
block/trace-events
View file

@ -64,9 +64,8 @@ file_paio_submit(void *acb, void *opaque, int64_t offset, int count, int type) "
# io_uring.c
luring_init_state(void *s, size_t size) "s %p size %zu"
luring_cleanup_state(void *s) "%p freed"
luring_io_plug(void *s) "LuringState %p plug"
luring_io_unplug(void *s, int blocked, int plugged, int queued, int inflight) "LuringState %p blocked %d plugged %d queued %d inflight %d"
luring_do_submit(void *s, int blocked, int plugged, int queued, int inflight) "LuringState %p blocked %d plugged %d queued %d inflight %d"
luring_unplug_fn(void *s, int blocked, int queued, int inflight) "LuringState %p blocked %d queued %d inflight %d"
luring_do_submit(void *s, int blocked, int queued, int inflight) "LuringState %p blocked %d queued %d inflight %d"
luring_do_submit_done(void *s, int ret) "LuringState %p submitted to kernel %d"
luring_co_submit(void *bs, void *s, void *luringcb, int fd, uint64_t offset, size_t nbytes, int type) "bs %p s %p luringcb %p fd %d offset %" PRId64 " nbytes %zd type %d"
luring_process_completion(void *s, void *aiocb, int ret) "LuringState %p luringcb %p ret %d"

7
include/block/raw-aio.h
View file

@ -81,13 +81,6 @@ int coroutine_fn luring_co_submit(BlockDriverState *bs, int fd, uint64_t offset,
QEMUIOVector *qiov, int type);
void luring_detach_aio_context(LuringState *s, AioContext *old_context);
void luring_attach_aio_context(LuringState *s, AioContext *new_context);
/*
* luring_io_plug/unplug work in the thread's current AioContext, therefore the
* caller must ensure that they are paired in the same IOThread.
*/
void luring_io_plug(void);
void luring_io_unplug(void);
#endif
#ifdef _WIN32