From 32220d38c04bdb0aeccfcd67715e11a655eb297b Mon Sep 17 00:00:00 2001 From: Sebastian Hahn Date: Thu, 20 Aug 2015 16:48:13 +0200 Subject: [PATCH] Ensure worker threads actually exit when it is time This includes a small refactoring to use a new enum (workqueue_reply_t) for the return values instead of just ints. --- changes/workqueue_reply_t | 6 ++++++ src/common/workqueue.c | 21 +++++++++++---------- src/common/workqueue.h | 19 ++++++++++--------- src/or/cpuworker.c | 4 ++-- src/test/test_workqueue.c | 8 ++++---- 5 files changed, 33 insertions(+), 25 deletions(-) create mode 100644 changes/workqueue_reply_t diff --git a/changes/workqueue_reply_t b/changes/workqueue_reply_t new file mode 100644 index 0000000000..c2d3f4ad65 --- /dev/null +++ b/changes/workqueue_reply_t @@ -0,0 +1,6 @@ + o Minor bugfixes: + - Ensure that worker threads actually exit when a fatal error or + shutdown is indicated. This doesn't currently affect the behaviour + of Tor, because Tor never indicates fatal error or shutdown except + in its unit tests. Fixes bug 16868; bugfix on 0.2.6.3-alpha. + diff --git a/src/common/workqueue.c b/src/common/workqueue.c index b0b004dc25..c467bdf43b 100644 --- a/src/common/workqueue.c +++ b/src/common/workqueue.c @@ -25,7 +25,7 @@ struct threadpool_s { unsigned generation; /** Function that should be run for updates on each thread. */ - int (*update_fn)(void *, void *); + workqueue_reply_t (*update_fn)(void *, void *); /** Function to free update arguments if they can't be run. */ void (*free_update_arg_fn)(void *); /** Array of n_threads update arguments. */ @@ -56,7 +56,7 @@ struct workqueue_entry_s { /** True iff this entry is waiting for a worker to start processing it. */ uint8_t pending; /** Function to run in the worker thread. */ - int (*fn)(void *state, void *arg); + workqueue_reply_t (*fn)(void *state, void *arg); /** Function to run while processing the reply queue. */ void (*reply_fn)(void *arg); /** Argument for the above functions. */ @@ -96,7 +96,7 @@ static void queue_reply(replyqueue_t *queue, workqueue_entry_t *work); * fn in the worker thread, and reply_fn in the main * thread. See threadpool_queue_work() for full documentation. */ static workqueue_entry_t * -workqueue_entry_new(int (*fn)(void*, void*), +workqueue_entry_new(workqueue_reply_t (*fn)(void*, void*), void (*reply_fn)(void*), void *arg) { @@ -172,7 +172,7 @@ worker_thread_main(void *thread_) workerthread_t *thread = thread_; threadpool_t *pool = thread->in_pool; workqueue_entry_t *work; - int result; + workqueue_reply_t result; tor_mutex_acquire(&pool->lock); while (1) { @@ -182,13 +182,14 @@ worker_thread_main(void *thread_) if (thread->in_pool->generation != thread->generation) { void *arg = thread->in_pool->update_args[thread->index]; thread->in_pool->update_args[thread->index] = NULL; - int (*update_fn)(void*,void*) = thread->in_pool->update_fn; + workqueue_reply_t (*update_fn)(void*,void*) = + thread->in_pool->update_fn; thread->generation = thread->in_pool->generation; tor_mutex_release(&pool->lock); - int r = update_fn(thread->state, arg); + workqueue_reply_t r = update_fn(thread->state, arg); - if (r < 0) { + if (r != WQ_RPL_REPLY) { return; } @@ -208,7 +209,7 @@ worker_thread_main(void *thread_) queue_reply(thread->reply_queue, work); /* We may need to exit the thread. */ - if (result >= WQ_RPL_ERROR) { + if (result != WQ_RPL_REPLY) { return; } tor_mutex_acquire(&pool->lock); @@ -281,7 +282,7 @@ workerthread_new(void *state, threadpool_t *pool, replyqueue_t *replyqueue) */ workqueue_entry_t * threadpool_queue_work(threadpool_t *pool, - int (*fn)(void *, void *), + workqueue_reply_t (*fn)(void *, void *), void (*reply_fn)(void *), void *arg) { @@ -318,7 +319,7 @@ threadpool_queue_work(threadpool_t *pool, int threadpool_queue_update(threadpool_t *pool, void *(*dup_fn)(void *), - int (*fn)(void *, void *), + workqueue_reply_t (*fn)(void *, void *), void (*free_fn)(void *), void *arg) { diff --git a/src/common/workqueue.h b/src/common/workqueue.h index 92e82b8a48..9ce1eadafc 100644 --- a/src/common/workqueue.h +++ b/src/common/workqueue.h @@ -15,21 +15,22 @@ typedef struct threadpool_s threadpool_t; * pool. */ typedef struct workqueue_entry_s workqueue_entry_t; -/** Possible return value from a work function: indicates success. */ -#define WQ_RPL_REPLY 0 -/** Possible return value from a work function: indicates fatal error */ -#define WQ_RPL_ERROR 1 -/** Possible return value from a work function: indicates thread is shutting - * down. */ -#define WQ_RPL_SHUTDOWN 2 +/** Possible return value from a work function: */ +typedef enum { + WQ_RPL_REPLY = 0, /** indicates success */ + WQ_RPL_ERROR = 1, /** indicates fatal error */ + WQ_RPL_SHUTDOWN = 2, /** indicates thread is shutting down */ +} workqueue_reply_t; workqueue_entry_t *threadpool_queue_work(threadpool_t *pool, - int (*fn)(void *, void *), + workqueue_reply_t (*fn)(void *, + void *), void (*reply_fn)(void *), void *arg); + int threadpool_queue_update(threadpool_t *pool, void *(*dup_fn)(void *), - int (*fn)(void *, void *), + workqueue_reply_t (*fn)(void *, void *), void (*free_fn)(void *), void *arg); void *workqueue_entry_cancel(workqueue_entry_t *pending_work); diff --git a/src/or/cpuworker.c b/src/or/cpuworker.c index d511ecf84c..76d97e05f2 100644 --- a/src/or/cpuworker.c +++ b/src/or/cpuworker.c @@ -160,7 +160,7 @@ typedef struct cpuworker_job_u { } u; } cpuworker_job_t; -static int +static workqueue_reply_t update_state_threadfn(void *state_, void *work_) { worker_state_t *state = state_; @@ -387,7 +387,7 @@ cpuworker_onion_handshake_replyfn(void *work_) } /** Implementation function for onion handshake requests. */ -static int +static workqueue_reply_t cpuworker_onion_handshake_threadfn(void *state_, void *work_) { worker_state_t *state = state_; diff --git a/src/test/test_workqueue.c b/src/test/test_workqueue.c index 1d2cd940c3..b6a10bb33f 100644 --- a/src/test/test_workqueue.c +++ b/src/test/test_workqueue.c @@ -70,7 +70,7 @@ mark_handled(int serial) #endif } -static int +static workqueue_reply_t workqueue_do_rsa(void *state, void *work) { rsa_work_t *rw = work; @@ -98,7 +98,7 @@ workqueue_do_rsa(void *state, void *work) return WQ_RPL_REPLY; } -static int +static workqueue_reply_t workqueue_do_shutdown(void *state, void *work) { (void)state; @@ -108,7 +108,7 @@ workqueue_do_shutdown(void *state, void *work) return WQ_RPL_SHUTDOWN; } -static int +static workqueue_reply_t workqueue_do_ecdh(void *state, void *work) { ecdh_work_t *ew = work; @@ -124,7 +124,7 @@ workqueue_do_ecdh(void *state, void *work) return WQ_RPL_REPLY; } -static int +static workqueue_reply_t workqueue_shutdown_error(void *state, void *work) { (void)state;