thread-pool: use ThreadPool from the running thread

Use qemu_get_current_aio_context() where possible, since we always
submit work to the current thread anyways.

We want to also be sure that the thread submitting the work is
the same as the one processing the pool, to avoid adding
synchronization to the pool list.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-4-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>

3 files changed, 12 insertions, 13 deletions

diff --git a/block/file-posix.c b/block/file-posix.c
index 30cb4ae421..173b3b1653 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -2040,11 +2040,10 @@ out:
     return result;
 }
 
-static int coroutine_fn raw_thread_pool_submit(BlockDriverState *bs,
-                                               ThreadPoolFunc func, void *arg)
+static int coroutine_fn raw_thread_pool_submit(ThreadPoolFunc func, void *arg)
 {
     /* @bs can be NULL, bdrv_get_aio_context() returns the main context then */
-    ThreadPool *pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
+    ThreadPool *pool = aio_get_thread_pool(qemu_get_current_aio_context());
     return thread_pool_submit_co(pool, func, arg);
 }
 
@@ -2112,7 +2111,7 @@ static int coroutine_fn raw_co_prw(BlockDriverState *bs, uint64_t offset,
     };
 
     assert(qiov->size == bytes);
-    return raw_thread_pool_submit(bs, handle_aiocb_rw, &acb);
+    return raw_thread_pool_submit(handle_aiocb_rw, &acb);
 }
 
 static int coroutine_fn raw_co_preadv(BlockDriverState *bs, int64_t offset,
@@ -2181,7 +2180,7 @@ static int coroutine_fn raw_co_flush_to_disk(BlockDriverState *bs)
         return luring_co_submit(bs, s->fd, 0, NULL, QEMU_AIO_FLUSH);
     }
 #endif
-    return raw_thread_pool_submit(bs, handle_aiocb_flush, &acb);
+    return raw_thread_pool_submit(handle_aiocb_flush, &acb);
 }
 
 static void raw_aio_attach_aio_context(BlockDriverState *bs,
@@ -2243,7 +2242,7 @@ raw_regular_truncate(BlockDriverState *bs, int fd, int64_t offset,
         },
     };
 
-    return raw_thread_pool_submit(bs, handle_aiocb_truncate, &acb);
+    return raw_thread_pool_submit(handle_aiocb_truncate, &acb);
 }
 
 static int coroutine_fn raw_co_truncate(BlockDriverState *bs, int64_t offset,
@@ -2992,7 +2991,7 @@ raw_do_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes,
         acb.aio_type |= QEMU_AIO_BLKDEV;
     }
 
-    ret = raw_thread_pool_submit(bs, handle_aiocb_discard, &acb);
+    ret = raw_thread_pool_submit(handle_aiocb_discard, &acb);
     raw_account_discard(s, bytes, ret);
     return ret;
 }
@@ -3067,7 +3066,7 @@ raw_do_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int64_t bytes,
         handler = handle_aiocb_write_zeroes;
     }
 
-    return raw_thread_pool_submit(bs, handler, &acb);
+    return raw_thread_pool_submit(handler, &acb);
 }
 
 static int coroutine_fn raw_co_pwrite_zeroes(
@@ -3305,7 +3304,7 @@ raw_co_copy_range_to(BlockDriverState *bs,
         },
     };
 
-    return raw_thread_pool_submit(bs, handle_aiocb_copy_range, &acb);
+    return raw_thread_pool_submit(handle_aiocb_copy_range, &acb);
 }
 
 BlockDriver bdrv_file = {
@@ -3635,7 +3634,7 @@ hdev_co_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
         struct sg_io_hdr *io_hdr = buf;
         if (io_hdr->cmdp[0] == PERSISTENT_RESERVE_OUT ||
             io_hdr->cmdp[0] == PERSISTENT_RESERVE_IN) {
-            return pr_manager_execute(s->pr_mgr, bdrv_get_aio_context(bs),
+            return pr_manager_execute(s->pr_mgr, qemu_get_current_aio_context(),
                                       s->fd, io_hdr);
         }
     }
@@ -3651,7 +3650,7 @@ hdev_co_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
         },
     };
 
-    return raw_thread_pool_submit(bs, handle_aiocb_ioctl, &acb);
+    return raw_thread_pool_submit(handle_aiocb_ioctl, &acb);
 }
 #endif /* linux */
 
diff --git a/block/file-win32.c b/block/file-win32.c
index 1763b8662e..0aedb0875c 100644
--- a/block/file-win32.c
+++ b/block/file-win32.c
@@ -168,7 +168,7 @@ static BlockAIOCB *paio_submit(BlockDriverState *bs, HANDLE hfile,
     acb->aio_offset = offset;
 
     trace_file_paio_submit(acb, opaque, offset, count, type);
-    pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
+    pool = aio_get_thread_pool(qemu_get_current_aio_context());
     return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
 }
 
diff --git a/block/qcow2-threads.c b/block/qcow2-threads.c
index 953bbe6df8..6d2e6b7bf4 100644
--- a/block/qcow2-threads.c
+++ b/block/qcow2-threads.c
@@ -43,7 +43,7 @@ qcow2_co_process(BlockDriverState *bs, ThreadPoolFunc *func, void *arg)
 {
     int ret;
     BDRVQcow2State *s = bs->opaque;
-    ThreadPool *pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
+    ThreadPool *pool = aio_get_thread_pool(qemu_get_current_aio_context());
 
     qemu_co_mutex_lock(&s->lock);
     while (s->nb_threads >= QCOW2_MAX_THREADS) {