[RFC,09/15] job.c: move inner aiocontext lock in callbacks

Commit Message

Emanuele Giuseppe Esposito Oct. 29, 2021, 4:39 p.m. UTC

Instead of having the lock in job_tnx_apply, move it inside
in the callback. This will be helpful for next commits, when
we introduce job_lock/unlock pairs.

job_transition_to_pending() and job_needs_finalize() do not
need to be protected by the aiocontext lock.

No functional change intended.

Signed-off-by: Emanuele Giuseppe Esposito <[e-mail]>
---
 job.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

Patch

diff --git a/job.c b/job.c
index 88d911f2d7..eb6d321960 100644
--- a/job.c
+++ b/job.c
@@ -153,7 +153,6 @@  static void job_txn_del_job(Job *job)
 
 static int job_txn_apply(Job *job, int fn(Job *))
 {
-    AioContext *inner_ctx;
     Job *other_job, *next;
     JobTxn *txn = job->txn;
     int rc = 0;
@@ -168,10 +167,7 @@  static int job_txn_apply(Job *job, int fn(Job *))
     aio_context_release(job->aio_context);
 
     QLIST_FOREACH_SAFE(other_job, &txn->jobs, txn_list, next) {
-        inner_ctx = other_job->aio_context;
-        aio_context_acquire(inner_ctx);
         rc = fn(other_job);
-        aio_context_release(inner_ctx);
         if (rc) {
             break;
         }
@@ -836,7 +832,10 @@  static void job_clean(Job *job)
 
 static int job_finalize_single(Job *job)
 {
+    AioContext *ctx = job->aio_context;
+
     assert(job_is_completed(job));
+    aio_context_acquire(ctx);
 
     /* Ensure abort is called for late-transactional failures */
     job_update_rc(job);
@@ -863,6 +862,7 @@  static int job_finalize_single(Job *job)
 
     job_txn_del_job(job);
     job_conclude(job);
+    aio_context_release(ctx);
     return 0;
 }
 
@@ -968,11 +968,16 @@  static void job_completed_txn_abort(Job *job)
 
 static int job_prepare(Job *job)
 {
+    AioContext *ctx = job->aio_context;
     assert(qemu_in_main_thread());
+
+    aio_context_acquire(ctx);
     if (job->ret == 0 && job->driver->prepare) {
         job->ret = job->driver->prepare(job);
         job_update_rc(job);
     }
+    aio_context_release(ctx);
+
     return job->ret;
 }