X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Faio%2Faio.c;h=d7e063bf93ca82fb5a6708a4bad7f8e1ead9e752;hb=0ab97350f01b42de0f9fd811ee08653169661859;hp=e004f98bcdd121fa89898fe601ba07882dd09636;hpb=34952fe5de44a833370cbe87b63fb8eec61466d7;p=musl diff --git a/src/aio/aio.c b/src/aio/aio.c index e004f98b..d7e063bf 100644 --- a/src/aio/aio.c +++ b/src/aio/aio.c @@ -76,8 +76,14 @@ static struct aio_queue *****map; static volatile int aio_fd_cnt; volatile int __aio_fut; +static size_t io_thread_stack_size; + +#define MAX(a,b) ((a)>(b) ? (a) : (b)) + static struct aio_queue *__aio_get_queue(int fd, int need) { + sigset_t allmask, origmask; + int masked = 0; if (fd < 0) { errno = EBADF; return 0; @@ -89,7 +95,14 @@ static struct aio_queue *__aio_get_queue(int fd, int need) if ((!map || !map[a] || !map[a][b] || !map[a][b][c] || !(q=map[a][b][c][d])) && need) { pthread_rwlock_unlock(&maplock); if (fcntl(fd, F_GETFD) < 0) return 0; + sigfillset(&allmask); + masked = 1; + pthread_sigmask(SIG_BLOCK, &allmask, &origmask); pthread_rwlock_wrlock(&maplock); + if (!io_thread_stack_size) { + unsigned long val = __getauxval(AT_MINSIGSTKSZ); + io_thread_stack_size = MAX(MINSIGSTKSZ+2048, val+512); + } if (!map) map = calloc(sizeof *map, (-1U/2+1)>>24); if (!map) goto out; if (!map[a]) map[a] = calloc(sizeof **map, 256); @@ -111,6 +124,7 @@ static struct aio_queue *__aio_get_queue(int fd, int need) if (q) pthread_mutex_lock(&q->lock); out: pthread_rwlock_unlock(&maplock); + if (masked) pthread_sigmask(SIG_SETMASK, &origmask, 0); return q; } @@ -265,15 +279,6 @@ static void *io_thread_func(void *ctx) return 0; } -static size_t io_thread_stack_size = MINSIGSTKSZ+2048; -static pthread_once_t init_stack_size_once; - -static void init_stack_size() -{ - unsigned long val = __getauxval(AT_MINSIGSTKSZ); - if (val > MINSIGSTKSZ) io_thread_stack_size = val + 512; -} - static int submit(struct aiocb *cb, int op) { int ret = 0; @@ -299,7 +304,6 @@ static int submit(struct aiocb *cb, int op) else pthread_attr_init(&a); } else { - pthread_once(&init_stack_size_once, init_stack_size); pthread_attr_init(&a); pthread_attr_setstacksize(&a, io_thread_stack_size); pthread_attr_setguardsize(&a, 0); @@ -403,18 +407,26 @@ void __aio_atfork(int who) if (who<0) { pthread_rwlock_rdlock(&maplock); return; + } else if (!who) { + pthread_rwlock_unlock(&maplock); + return; } - if (who>0 && map) for (int a=0; a<(-1U/2+1)>>24; a++) + aio_fd_cnt = 0; + if (pthread_rwlock_tryrdlock(&maplock)) { + /* Obtaining lock may fail if _Fork was called nor via + * fork. In this case, no further aio is possible from + * child and we can just null out map so __aio_close + * does not attempt to do anything. */ + map = 0; + return; + } + if (map) for (int a=0; a<(-1U/2+1)>>24; a++) if (map[a]) for (int b=0; b<256; b++) if (map[a][b]) for (int c=0; c<256; c++) if (map[a][b][c]) for (int d=0; d<256; d++) map[a][b][c][d] = 0; - pthread_rwlock_unlock(&maplock); + /* Re-initialize the rwlock rather than unlocking since there + * may have been more than one reference on it in the parent. + * We are not a lock holder anyway; the thread in the parent was. */ + pthread_rwlock_init(&maplock, 0); } - -weak_alias(aio_cancel, aio_cancel64); -weak_alias(aio_error, aio_error64); -weak_alias(aio_fsync, aio_fsync64); -weak_alias(aio_read, aio_read64); -weak_alias(aio_write, aio_write64); -weak_alias(aio_return, aio_return64);