diff options
| author | Emanuele Giuseppe Esposito <eesposit@redhat.com> | 2022-09-26 05:31:57 -0400 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2022-10-07 12:11:41 +0200 |
| commit | fd4b14e299d7def753f2d753e61d125cd5e1cbd8 (patch) | |
| tree | ae4461e0c515d59e3af7c88ebb4e608da13fcdce /include/block | |
| parent | 544f4d5258d4e4dd6652d28607b605e7801ed7dd (diff) | |
aio-wait.h: introduce AIO_WAIT_WHILE_UNLOCKED
Same as AIO_WAIT_WHILE macro, but if we are in the Main loop
do not release and then acquire ctx_ 's aiocontext.
Once all Aiocontext locks go away, this macro will replace
AIO_WAIT_WHILE.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20220926093214.506243-5-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'include/block')
| -rw-r--r-- | include/block/aio-wait.h | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/include/block/aio-wait.h b/include/block/aio-wait.h index 54840f8622..dd9a7f6461 100644 --- a/include/block/aio-wait.h +++ b/include/block/aio-wait.h @@ -59,10 +59,13 @@ typedef struct { extern AioWait global_aio_wait; /** - * AIO_WAIT_WHILE: + * AIO_WAIT_WHILE_INTERNAL: * @ctx: the aio context, or NULL if multiple aio contexts (for which the * caller does not hold a lock) are involved in the polling condition. * @cond: wait while this conditional expression is true + * @unlock: whether to unlock and then lock again @ctx. This apples + * only when waiting for another AioContext from the main loop. + * Otherwise it's ignored. * * Wait while a condition is true. Use this to implement synchronous * operations that require event loop activity. @@ -75,7 +78,7 @@ extern AioWait global_aio_wait; * wait on conditions between two IOThreads since that could lead to deadlock, * go via the main loop instead. */ -#define AIO_WAIT_WHILE(ctx, cond) ({ \ +#define AIO_WAIT_WHILE_INTERNAL(ctx, cond, unlock) ({ \ bool waited_ = false; \ AioWait *wait_ = &global_aio_wait; \ AioContext *ctx_ = (ctx); \ @@ -92,11 +95,11 @@ extern AioWait global_aio_wait; assert(qemu_get_current_aio_context() == \ qemu_get_aio_context()); \ while ((cond)) { \ - if (ctx_) { \ + if (unlock && ctx_) { \ aio_context_release(ctx_); \ } \ aio_poll(qemu_get_aio_context(), true); \ - if (ctx_) { \ + if (unlock && ctx_) { \ aio_context_acquire(ctx_); \ } \ waited_ = true; \ @@ -105,6 +108,12 @@ extern AioWait global_aio_wait; qatomic_dec(&wait_->num_waiters); \ waited_; }) +#define AIO_WAIT_WHILE(ctx, cond) \ + AIO_WAIT_WHILE_INTERNAL(ctx, cond, true) + +#define AIO_WAIT_WHILE_UNLOCKED(ctx, cond) \ + AIO_WAIT_WHILE_INTERNAL(ctx, cond, false) + /** * aio_wait_kick: * Wake up the main thread if it is waiting on AIO_WAIT_WHILE(). During |