motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-02 15:23:53 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

io_uring: use LuringState from the running thread

Browse source 
Remove usage of aio_context_acquire by always submitting asynchronous
AIO to the current thread's LuringState.

In order to prevent mistakes from the caller side, avoid passing LuringState
in luring_io_{plug/unplug} and luring_co_submit, and document the functions
to make clear that they work in the current thread's AioContext.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-3-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Emanuele Giuseppe Esposito 2023-02-03 08:17:29 -05:00 • committed by Kevin Wolf
parent ab50533b69
commit a75e4e4365
4 changed files with 30 additions and 24 deletions
Download patch file Download diff file Expand all files Collapse all files

23
block/io_uring.c
View file

@ -18,6 +18,9 @@
#include "qapi/error.h"
#include "trace.h"
/* Only used for assertions. */
#include "qemu/coroutine_int.h"
/* io_uring ring size */
#define MAX_ENTRIES 128
@ -50,10 +53,9 @@ typedef struct LuringState {
struct io_uring ring;
/* io queue for submit at batch. Protected by AioContext lock. */
/* No locking required, only accessed from AioContext home thread */
LuringQueue io_q;
/* I/O completion processing. Only runs in I/O thread. */
QEMUBH *completion_bh;
} LuringState;
@ -209,6 +211,7 @@ end:
* eventually runs later. Coroutines cannot be entered recursively
* so avoid doing that!
*/
assert(luringcb->co->ctx == s->aio_context);
if (!qemu_coroutine_entered(luringcb->co)) {
aio_co_wake(luringcb->co);
}
@ -262,13 +265,11 @@ static int ioq_submit(LuringState *s)
static void luring_process_completions_and_submit(LuringState *s)
{
aio_context_acquire(s->aio_context);
luring_process_completions(s);
if (!s->io_q.plugged && s->io_q.in_queue > 0) {
ioq_submit(s);
}
aio_context_release(s->aio_context);
}
static void qemu_luring_completion_bh(void *opaque)
@ -306,14 +307,18 @@ static void ioq_init(LuringQueue *io_q)
io_q->blocked = false;
}
void luring_io_plug(BlockDriverState *bs, LuringState *s)
void luring_io_plug(void)
{
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(BlockDriverState *bs, LuringState *s)
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);
@ -373,10 +378,12 @@ static int luring_do_submit(int fd, LuringAIOCB *luringcb, LuringState *s,
return 0;
}
int coroutine_fn luring_co_submit(BlockDriverState *bs, LuringState *s, int fd,
uint64_t offset, QEMUIOVector *qiov, int type)
int coroutine_fn luring_co_submit(BlockDriverState *bs, int fd, uint64_t offset,
QEMUIOVector *qiov, int type)
{
int ret;
AioContext *ctx = qemu_get_current_aio_context();
LuringState *s = aio_get_linux_io_uring(ctx);
LuringAIOCB luringcb = {
.co = qemu_coroutine_self(),
.ret = -EINPROGRESS,