ShuriZma
/
xemu
mirror of https://github.com/xemu-project/xemu.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

qemu-coroutine: remove qatomic_mb_read() 

Replace with an explicit barrier and a comment.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2023-03-03 11:00:43 +01:00
parent 4592eaf387
commit 512c90c90e
1 changed files with 7 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
util/qemu-coroutine.c
View File

@ -127,9 +127,13 @@ void qemu_aio_coroutine_enter(AioContext *ctx, Coroutine *co)
Coroutine *to = QSIMPLEQ_FIRST(&pending); Coroutine *to = QSIMPLEQ_FIRST(&pending);
CoroutineAction ret; CoroutineAction ret;
/* Cannot rely on the read barrier for to in aio_co_wake(), as there are /*
* callers outside of aio_co_wake() */ * Read to before to->scheduled; pairs with qatomic_cmpxchg in
const char *scheduled = qatomic_mb_read(&to->scheduled); * qemu_co_sleep(), aio_co_schedule() etc.
*/
smp_read_barrier_depends();
const char *scheduled = qatomic_read(&to->scheduled);
QSIMPLEQ_REMOVE_HEAD(&pending, co_queue_next); QSIMPLEQ_REMOVE_HEAD(&pending, co_queue_next);