diff options
Diffstat (limited to 'libglusterfs/src/mem-pool.c')
| -rw-r--r-- | libglusterfs/src/mem-pool.c | 62 |
1 files changed, 48 insertions, 14 deletions
diff --git a/libglusterfs/src/mem-pool.c b/libglusterfs/src/mem-pool.c index 343771e38a1..b064837ac00 100644 --- a/libglusterfs/src/mem-pool.c +++ b/libglusterfs/src/mem-pool.c @@ -519,12 +519,6 @@ mem_pools_preinit (void) { unsigned int i; - /* Use a pthread_key destructor to clean up when a thread exits. */ - if (pthread_key_create (&pool_key, pool_destructor) != 0) { - gf_log ("mem-pool", GF_LOG_CRITICAL, - "failed to initialize mem-pool key"); - } - INIT_LIST_HEAD (&pool_threads); INIT_LIST_HEAD (&pool_free_threads); @@ -546,8 +540,34 @@ static pthread_mutex_t init_mutex = PTHREAD_MUTEX_INITIALIZER; static unsigned int init_count = 0; static pthread_t sweeper_tid; +/* Use mem_pools_init_early() function for basic initialization. There will be + * no cleanup done by the pool_sweeper thread until mem_pools_init_late() has + * been called. Calling mem_get() will be possible after this function has + * setup the basic structures. */ void -mem_pools_init (void) +mem_pools_init_early (void) +{ + pthread_mutex_lock (&init_mutex); + /* Use a pthread_key destructor to clean up when a thread exits. + * + * We won't increase init_count here, that is only done when the + * pool_sweeper thread is started too. + */ + if (pthread_getspecific (pool_key) == NULL) { + /* key has not been created yet */ + if (pthread_key_create (&pool_key, pool_destructor) != 0) { + gf_log ("mem-pool", GF_LOG_CRITICAL, + "failed to initialize mem-pool key"); + } + } + pthread_mutex_unlock (&init_mutex); +} + +/* Call mem_pools_init_late() once threading has been configured completely. + * This prevent the pool_sweeper thread from getting killed once the main() + * thread exits during deamonizing. */ +void +mem_pools_init_late (void) { pthread_mutex_lock (&init_mutex); if ((init_count++) == 0) { @@ -565,17 +585,30 @@ mem_pools_fini (void) case 0: /* * If init_count is already zero (as e.g. if somebody called - * this before mem_pools_init) then the sweeper was probably - * never even started so we don't need to stop it. Even if - * there's some crazy circumstance where there is a sweeper but - * init_count is still zero, that just means we'll leave it - * running. Not perfect, but far better than any known - * alternative. + * this before mem_pools_init_late) then the sweeper was + * probably never even started so we don't need to stop it. + * Even if there's some crazy circumstance where there is a + * sweeper but init_count is still zero, that just means we'll + * leave it running. Not perfect, but far better than any + * known alternative. */ break; case 1: + /* if only mem_pools_init_early() was called, sweeper_tid will + * be invalid and the functions will error out. That is not + * critical. In all other cases, the sweeper_tid will be valid + * and the thread gets stopped. */ (void) pthread_cancel (sweeper_tid); (void) pthread_join (sweeper_tid, NULL); + + /* Need to clean the pool_key to prevent further usage of the + * per_thread_pool_list_t structure that is stored for each + * thread. + * This also prevents calling pool_destructor() when a thread + * exits, so there is no chance on a use-after-free of the + * per_thread_pool_list_t structure. */ + (void) pthread_key_delete (pool_key); + /* Fall through. */ default: --init_count; @@ -584,7 +617,8 @@ mem_pools_fini (void) } #else -void mem_pools_init (void) {} +void mem_pools_init_early (void) {} +void mem_pools_init_late (void) {} void mem_pools_fini (void) {} #endif |