From ba3186c4e473963ba83b5792f3d02d4ac0a76ba5 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 22 Feb 2017 19:07:23 +0100 Subject: [PATCH] curl: do not use aio_context_acquire/release Now that all bottom halves and callbacks take care of taking the AioContext lock, we can migrate some users away from it and to a specific QemuMutex or CoMutex. Protect BDRVCURLState access with a QemuMutex. Reviewed-by: Stefan Hajnoczi Signed-off-by: Paolo Bonzini Message-id: 20170222180725.28611-2-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi --- block/curl.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/block/curl.c b/block/curl.c index 2939cc77e9..e83dcd8f50 100644 --- a/block/curl.c +++ b/block/curl.c @@ -135,6 +135,7 @@ typedef struct BDRVCURLState { char *cookie; bool accept_range; AioContext *aio_context; + QemuMutex mutex; char *username; char *password; char *proxyusername; @@ -333,6 +334,7 @@ static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len, return FIND_RET_NONE; } +/* Called with s->mutex held. */ static void curl_multi_check_completion(BDRVCURLState *s) { int msgs_in_queue; @@ -374,7 +376,9 @@ static void curl_multi_check_completion(BDRVCURLState *s) continue; } + qemu_mutex_unlock(&s->mutex); acb->common.cb(acb->common.opaque, -EPROTO); + qemu_mutex_lock(&s->mutex); qemu_aio_unref(acb); state->acb[i] = NULL; } @@ -386,6 +390,7 @@ static void curl_multi_check_completion(BDRVCURLState *s) } } +/* Called with s->mutex held. */ static void curl_multi_do_locked(CURLState *s) { CURLSocket *socket, *next_socket; @@ -409,19 +414,19 @@ static void curl_multi_do(void *arg) { CURLState *s = (CURLState *)arg; - aio_context_acquire(s->s->aio_context); + qemu_mutex_lock(&s->s->mutex); curl_multi_do_locked(s); - aio_context_release(s->s->aio_context); + qemu_mutex_unlock(&s->s->mutex); } static void curl_multi_read(void *arg) { CURLState *s = (CURLState *)arg; - aio_context_acquire(s->s->aio_context); + qemu_mutex_lock(&s->s->mutex); curl_multi_do_locked(s); curl_multi_check_completion(s->s); - aio_context_release(s->s->aio_context); + qemu_mutex_unlock(&s->s->mutex); } static void curl_multi_timeout_do(void *arg) @@ -434,11 +439,11 @@ static void curl_multi_timeout_do(void *arg) return; } - aio_context_acquire(s->aio_context); + qemu_mutex_lock(&s->mutex); curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running); curl_multi_check_completion(s); - aio_context_release(s->aio_context); + qemu_mutex_unlock(&s->mutex); #else abort(); #endif @@ -771,6 +776,7 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags, curl_easy_cleanup(state->curl); state->curl = NULL; + qemu_mutex_init(&s->mutex); curl_attach_aio_context(bs, bdrv_get_aio_context(bs)); qemu_opts_del(opts); @@ -801,12 +807,11 @@ static void curl_readv_bh_cb(void *p) CURLAIOCB *acb = p; BlockDriverState *bs = acb->common.bs; BDRVCURLState *s = bs->opaque; - AioContext *ctx = bdrv_get_aio_context(bs); size_t start = acb->sector_num * BDRV_SECTOR_SIZE; size_t end; - aio_context_acquire(ctx); + qemu_mutex_lock(&s->mutex); // In case we have the requested data already (e.g. read-ahead), // we can just call the callback and be done. @@ -854,7 +859,7 @@ static void curl_readv_bh_cb(void *p) curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running); out: - aio_context_release(ctx); + qemu_mutex_unlock(&s->mutex); if (ret != -EINPROGRESS) { acb->common.cb(acb->common.opaque, ret); qemu_aio_unref(acb); @@ -883,6 +888,7 @@ static void curl_close(BlockDriverState *bs) DPRINTF("CURL: Close\n"); curl_detach_aio_context(bs); + qemu_mutex_destroy(&s->mutex); g_free(s->cookie); g_free(s->url); -- 2.11.4.GIT