diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | nptl/Makefile | 2 | ||||
| -rw-r--r-- | nptl/allocatestack.c | 24 | ||||
| -rw-r--r-- | nptl/descr.h | 45 | ||||
| -rw-r--r-- | nptl/init.c | 28 | ||||
| -rw-r--r-- | nptl/pthreadP.h | 31 | ||||
| -rw-r--r-- | nptl/pthread_create.c | 46 | ||||
| -rw-r--r-- | nptl/pthread_mutex_consistent.c | 2 | ||||
| -rw-r--r-- | nptl/pthread_mutex_destroy.c | 12 | ||||
| -rw-r--r-- | nptl/pthread_mutex_init.c | 17 | ||||
| -rw-r--r-- | nptl/pthread_mutex_lock.c | 50 | ||||
| -rw-r--r-- | nptl/pthread_mutex_timedlock.c | 44 | ||||
| -rw-r--r-- | nptl/pthread_mutex_trylock.c | 51 | ||||
| -rw-r--r-- | nptl/pthread_mutex_unlock.c | 16 | ||||
| -rw-r--r-- | nptl/tst-robust8.c | 264 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/kernel-features.h | 6 |
16 files changed, 520 insertions, 123 deletions
diff --git a/ChangeLog b/ChangeLog index 31d788808e..17b6f319ed 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2006-03-27 Ulrich Drepper <drepper@redhat.com> + + * sysdeps/unix/sysv/linux/kernel-features.h: Add + __ASSUME_SET_ROBUST_LIST. + 2006-03-27 Jakub Jelinek <jakub@redhat.com> * wcsmbs/wchar.h (btowc, wctob): Don't optimize in C++. diff --git a/nptl/Makefile b/nptl/Makefile index e0da9504f1..8229486a25 100644 --- a/nptl/Makefile +++ b/nptl/Makefile @@ -206,7 +206,7 @@ tests = tst-typesizes \ tst-cond14 tst-cond15 tst-cond16 tst-cond17 tst-cond18 tst-cond19 \ tst-cond20 tst-cond21 \ tst-robust1 tst-robust2 tst-robust3 tst-robust4 tst-robust5 \ - tst-robust6 tst-robust7 \ + tst-robust6 tst-robust7 tst-robust8 \ tst-rwlock1 tst-rwlock2 tst-rwlock3 tst-rwlock4 tst-rwlock5 \ tst-rwlock6 tst-rwlock7 tst-rwlock8 tst-rwlock9 tst-rwlock10 \ tst-rwlock11 tst-rwlock12 tst-rwlock13 tst-rwlock14 \ diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c index 046a2470fc..a3ed1a33d3 100644 --- a/nptl/allocatestack.c +++ b/nptl/allocatestack.c @@ -365,12 +365,6 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp, /* The process ID is also the same as that of the caller. */ pd->pid = THREAD_GETMEM (THREAD_SELF, pid); - /* List of robust mutexes. */ -#ifdef __PTHREAD_MUTEX_HAVE_PREV - pd->robust_list.__prev = &pd->robust_list; -#endif - pd->robust_list.__next = &pd->robust_list; - /* Allocate the DTV for this thread. */ if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL) { @@ -505,12 +499,6 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp, /* The process ID is also the same as that of the caller. */ pd->pid = THREAD_GETMEM (THREAD_SELF, pid); - /* List of robust mutexes. */ -#ifdef __PTHREAD_MUTEX_HAVE_PREV - pd->robust_list.__prev = &pd->robust_list; -#endif - pd->robust_list.__next = &pd->robust_list; - /* Allocate the DTV for this thread. */ if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL) { @@ -634,6 +622,18 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp, stillborn thread could be canceled while the lock is taken. */ pd->lock = LLL_LOCK_INITIALIZER; + /* The robust mutex lists also need to be initialized + unconditionally because the cleanup for the previous stack owner + might have happened in the kernel. */ + pd->robust_head.futex_offset = (offsetof (pthread_mutex_t, __data.__lock) + - offsetof (pthread_mutex_t, + __data.__list.__next)); + pd->robust_head.list_op_pending = NULL; +#ifdef __PTHREAD_MUTEX_HAVE_PREV + pd->robust_prev = &pd->robust_head; +#endif + pd->robust_head.list = &pd->robust_head; + /* We place the thread descriptor at the end of the stack. */ *pdp = pd; diff --git a/nptl/descr.h b/nptl/descr.h index 80251b920b..f89d3240da 100644 --- a/nptl/descr.h +++ b/nptl/descr.h @@ -102,6 +102,15 @@ struct xid_command }; +/* Data structure used by the kernel to find robust futexes. */ +struct robust_list_head +{ + void *list; + long int futex_offset; + void *list_op_pending; +}; + + /* Thread descriptor data structure. */ struct pthread { @@ -136,25 +145,43 @@ struct pthread /* List of robust mutexes the thread is holding. */ #ifdef __PTHREAD_MUTEX_HAVE_PREV - __pthread_list_t robust_list; + void *robust_prev; + struct robust_list_head robust_head; + + /* The list above is strange. It is basically a double linked list + but the pointer to the next/previous element of the list points + in the middle of the object, the __next element. Whenever + casting to __pthread_list_t we need to adjust the pointer + first. */ +# define QUEUE_PTR_ADJUST (offsetof (__pthread_list_t, __next)) # define ENQUEUE_MUTEX(mutex) \ do { \ - __pthread_list_t *next = THREAD_GETMEM (THREAD_SELF, robust_list.__next); \ - next->__prev = &mutex->__data.__list; \ - mutex->__data.__list.__next = next; \ - mutex->__data.__list.__prev = &THREAD_SELF->robust_list; \ - THREAD_SETMEM (THREAD_SELF, robust_list.__next, &mutex->__data.__list); \ + __pthread_list_t *next = (THREAD_GETMEM (THREAD_SELF, robust_head.list) \ + - QUEUE_PTR_ADJUST); \ + next->__prev = (void *) &mutex->__data.__list.__next; \ + mutex->__data.__list.__next = (void *) &next->__next; \ + mutex->__data.__list.__prev = (void *) &THREAD_SELF->robust_head; \ + THREAD_SETMEM (THREAD_SELF, robust_head.list, \ + &mutex->__data.__list.__next); \ } while (0) # define DEQUEUE_MUTEX(mutex) \ do { \ - mutex->__data.__list.__next->__prev = mutex->__data.__list.__prev; \ - mutex->__data.__list.__prev->__next = mutex->__data.__list.__next; \ + __pthread_list_t *next = (__pthread_list_t *) \ + ((char *) mutex->__data.__list.__next - QUEUE_PTR_ADJUST); \ + next->__prev = mutex->__data.__list.__prev; \ + __pthread_list_t *prev = (__pthread_list_t *) \ + ((char *) mutex->__data.__list.__prev - QUEUE_PTR_ADJUST); \ + prev->__next = mutex->__data.__list.__next; \ mutex->__data.__list.__prev = NULL; \ mutex->__data.__list.__next = NULL; \ } while (0) #else - __pthread_slist_t robust_list; + union + { + __pthread_slist_t robust_list; + struct robust_list_head robust_head; + }; # define ENQUEUE_MUTEX(mutex) \ do { \ diff --git a/nptl/init.c b/nptl/init.c index cb63ff7a6d..4db3e0c828 100644 --- a/nptl/init.c +++ b/nptl/init.c @@ -60,6 +60,15 @@ size_t __static_tls_size; size_t __static_tls_align_m1; +#ifndef __ASSUME_SET_ROBUST_LIST +/* Negative if we do not have the system call and we can use it. */ +int __set_robust_list_avail; +# define set_robust_list_not_avail() \ + __set_robust_list_avail = -1 +#else +# define set_robust_list_not_avail() do { } while (0) +#endif + /* Version of the library, used in libthread_db to detect mismatches. */ static const char nptl_version[] __attribute_used__ = VERSION; @@ -247,10 +256,6 @@ __pthread_initialize_minimal_internal (void) struct pthread *pd = THREAD_SELF; INTERNAL_SYSCALL_DECL (err); pd->pid = pd->tid = INTERNAL_SYSCALL (set_tid_address, err, 1, &pd->tid); -#ifdef __PTHREAD_MUTEX_HAVE_PREV - pd->robust_list.__prev = &pd->robust_list; -#endif - pd->robust_list.__next = &pd->robust_list; THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]); THREAD_SETMEM (pd, user_stack, true); if (LLL_LOCK_INITIALIZER != 0) @@ -259,6 +264,21 @@ __pthread_initialize_minimal_internal (void) THREAD_SETMEM (pd, cpuclock_offset, GL(dl_cpuclock_offset)); #endif + /* Initialize the robust mutex data. */ +#ifdef __PTHREAD_MUTEX_HAVE_PREV + pd->robust_prev = &pd->robust_head; +#endif + pd->robust_head.list = &pd->robust_head; +#ifdef __NR_set_robust_list + pd->robust_head.futex_offset = (offsetof (pthread_mutex_t, __data.__lock) + - offsetof (pthread_mutex_t, + __data.__list.__next)); + int res = INTERNAL_SYSCALL (set_robust_list, err, 2, &pd->robust_head, + sizeof (struct robust_list_head)); + if (INTERNAL_SYSCALL_ERROR_P (res, err)) +#endif + set_robust_list_not_avail (); + /* Set initial thread's stack block from 0 up to __libc_stack_end. It will be bigger than it actually is, but for unwind.c/pt-longjmp.c purposes this is good enough. */ diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h index a4d6d1a1ae..7b3da83786 100644 --- a/nptl/pthreadP.h +++ b/nptl/pthreadP.h @@ -31,6 +31,7 @@ #include <internaltypes.h> #include <pthread-functions.h> #include <atomic.h> +#include <kernel-features.h> /* Atomic operations on TLS memory. */ @@ -60,13 +61,13 @@ /* Internal mutex type value. */ enum { - PTHREAD_MUTEX_ROBUST_PRIVATE_NP = 16, - PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP - = PTHREAD_MUTEX_ROBUST_PRIVATE_NP | PTHREAD_MUTEX_RECURSIVE_NP, - PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP - = PTHREAD_MUTEX_ROBUST_PRIVATE_NP | PTHREAD_MUTEX_ERRORCHECK_NP, - PTHREAD_MUTEX_ROBUST_PRIVATE_ADAPTIVE_NP - = PTHREAD_MUTEX_ROBUST_PRIVATE_NP | PTHREAD_MUTEX_ADAPTIVE_NP, + PTHREAD_MUTEX_ROBUST_NORMAL_NP = 16, + PTHREAD_MUTEX_ROBUST_RECURSIVE_NP + = PTHREAD_MUTEX_ROBUST_NORMAL_NP | PTHREAD_MUTEX_RECURSIVE_NP, + PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP + = PTHREAD_MUTEX_ROBUST_NORMAL_NP | PTHREAD_MUTEX_ERRORCHECK_NP, + PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP + = PTHREAD_MUTEX_ROBUST_NORMAL_NP | PTHREAD_MUTEX_ADAPTIVE_NP, PTHREAD_MUTEX_PRIO_INHERIT_PRIVATE_NP = 32, PTHREAD_MUTEX_PRIO_PROTECT_PRIVATE_NP = 64 }; @@ -128,6 +129,11 @@ hidden_proto (__pthread_keys) /* Number of threads running. */ extern unsigned int __nptl_nthreads attribute_hidden; +#ifndef __ASSUME_SET_ROBUST_LIST +/* Negative if we do not have the system call and we can use it. */ +extern int __set_robust_list_avail attribute_hidden; +#endif + /* The library can run in debugging mode where it performs a lot more tests. */ extern int __pthread_debug attribute_hidden; @@ -504,4 +510,15 @@ extern int __nptl_setxid (struct xid_command *cmdp) attribute_hidden; # define PTHREAD_STATIC_FN_REQUIRE(name) __asm (".globl " #name); #endif + +#ifndef __NR_set_robust_list +/* XXX For the time being... Once we can rely on the kernel headers + having the definition remove these lines. */ +# if defined __i386__ +# define __NR_set_robust_list 311 +# elif defined __x86_64__ +# define __NR_set_robust_list 273 +# endif +#endif + #endif /* pthreadP.h */ diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c index f3d90ecebf..71365a17e8 100644 --- a/nptl/pthread_create.c +++ b/nptl/pthread_create.c @@ -229,6 +229,19 @@ start_thread (void *arg) /* Initialize resolver state pointer. */ __resp = &pd->res; +#ifdef __NR_set_robust_list +# ifndef __ASSUME_SET_ROBUST_LIST + if (__set_robust_list_avail >= 0) +# endif + { + INTERNAL_SYSCALL_DECL (err); + /* This call should never fail because the initial call in init.c + succeeded. */ + INTERNAL_SYSCALL (set_robust_list, err, 2, &pd->robust_head, + sizeof (struct robust_list_head)); + } +#endif + /* This is where the try/finally block should be created. For compilers without that support we do use setjmp. */ struct pthread_unwind_buf unwind_buf; @@ -310,35 +323,34 @@ start_thread (void *arg) the breakpoint reports TD_THR_RUN state rather than TD_THR_ZOMBIE. */ atomic_bit_set (&pd->cancelhandling, EXITING_BIT); +#ifndef __ASSUME_SET_ROBUST_LIST /* If this thread has any robust mutexes locked, handle them now. */ -#if __WORDSIZE == 64 - __pthread_list_t *robust = pd->robust_list.__next; -#else +# if __WORDSIZE == 64 + void *robust = pd->robust_head.list; +# else __pthread_slist_t *robust = pd->robust_list.__next; -#endif - if (__builtin_expect (robust != &pd->robust_list, 0)) +# endif +/* We let the kernel do the notification if it is able to do so. */ + if (__set_robust_list_avail < 0 + && __builtin_expect (robust != &pd->robust_head, 0)) { do { struct __pthread_mutex_s *this = (struct __pthread_mutex_s *) - ((char *) robust - offsetof (struct __pthread_mutex_s, __list)); - robust = robust->__next; + ((char *) robust - offsetof (struct __pthread_mutex_s, + __list.__next)); + robust = *((void **) robust); - this->__list.__next = NULL; -#ifdef __PTHREAD_MUTEX_HAVE_PREV +# ifdef __PTHREAD_MUTEX_HAVE_PREV this->__list.__prev = NULL; -#endif +# endif + this->__list.__next = NULL; lll_robust_mutex_dead (this->__lock); } - while (robust != &pd->robust_list); - - /* Clean up so that the thread descriptor can be reused. */ - pd->robust_list.__next = &pd->robust_list; -#ifdef __PTHREAD_MUTEX_HAVE_PREV - pd->robust_list.__prev = &pd->robust_list; -#endif + while (robust != &pd->robust_head); } +#endif /* If the thread is detached free the TCB. */ if (IS_DETACHED (pd)) diff --git a/nptl/pthread_mutex_consistent.c b/nptl/pthread_mutex_consistent.c index 0cfe972da0..d4f287b755 100644 --- a/nptl/pthread_mutex_consistent.c +++ b/nptl/pthread_mutex_consistent.c @@ -26,7 +26,7 @@ pthread_mutex_consistent_np (mutex) pthread_mutex_t *mutex; { /* Test whether this is a robust mutex with a dead owner. */ - if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_PRIVATE_NP) == 0 + if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) == 0 || mutex->__data.__owner != PTHREAD_MUTEX_INCONSISTENT) return EINVAL; diff --git a/nptl/pthread_mutex_destroy.c b/nptl/pthread_mutex_destroy.c index 19a647a846..7829979f35 100644 --- a/nptl/pthread_mutex_destroy.c +++ b/nptl/pthread_mutex_destroy.c @@ -25,15 +25,9 @@ int __pthread_mutex_destroy (mutex) pthread_mutex_t *mutex; { - if (mutex->__data.__nusers != 0) - { - if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_PRIVATE_NP) != 0 - && (mutex->__data.__lock & FUTEX_OWNER_DIED) != 0 - && mutex->__data.__nusers == 1) - goto dead_robust_mutex; - - return EBUSY; - } + if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) == 0 + && mutex->__data.__nusers != 0) + return EBUSY; /* Set to an invalid value. */ dead_robust_mutex: diff --git a/nptl/pthread_mutex_init.c b/nptl/pthread_mutex_init.c index f984d90ae4..c25e4035e5 100644 --- a/nptl/pthread_mutex_init.c +++ b/nptl/pthread_mutex_init.c @@ -22,7 +22,6 @@ #include <string.h> #include "pthreadP.h" - static const struct pthread_mutexattr default_attr = { /* Default is a normal mutex, not shared between processes. */ @@ -42,10 +41,6 @@ __pthread_mutex_init (mutex, mutexattr) imutexattr = (const struct pthread_mutexattr *) mutexattr ?: &default_attr; /* Sanity checks. */ - // XXX For now we cannot implement robust mutexes if they are shared. - if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0 - && (imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_PSHARED) != 0) - return ENOTSUP; // XXX For now we don't support priority inherited or priority protected // XXX mutexes. if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_PROTOCOL_MASK) @@ -57,8 +52,18 @@ __pthread_mutex_init (mutex, mutexattr) /* Copy the values from the attribute. */ mutex->__data.__kind = imutexattr->mutexkind & ~PTHREAD_MUTEXATTR_FLAG_BITS; + if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0) - mutex->__data.__kind |= PTHREAD_MUTEX_ROBUST_PRIVATE_NP; + { +#ifndef __ASSUME_SET_ROBUST_LIST + if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_PSHARED) != 0 + && __set_robust_list_avail < 0) + return ENOTSUP; +#endif + + mutex->__data.__kind |= PTHREAD_MUTEX_ROBUST_NORMAL_NP; + } + switch ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_PROTOCOL_MASK) >> PTHREAD_MUTEXATTR_PROTOCOL_SHIFT) { diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c index dd22567c71..06eef49c71 100644 --- a/nptl/pthread_mutex_lock.c +++ b/nptl/pthread_mutex_lock.c @@ -108,25 +108,33 @@ __pthread_mutex_lock (mutex) assert (mutex->__data.__owner == 0); break; - case PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ADAPTIVE_NP: + case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: + case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: + case PTHREAD_MUTEX_ROBUST_NORMAL_NP: + case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + &mutex->__data.__list.__next); + oldval = mutex->__data.__lock; do { + again: if ((oldval & FUTEX_OWNER_DIED) != 0) { /* The previous owner died. Try locking the mutex. */ - int newval; - while ((newval - = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - id, oldval)) - != oldval) + int newval = id; +#ifdef NO_INCR + newval |= FUTEX_WAITERS; +#endif + + newval + = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, + newval, oldval); + + if (newval != oldval) { - if ((newval & FUTEX_OWNER_DIED) == 0) - goto normal; oldval = newval; + goto again; } /* We got the mutex. */ @@ -135,6 +143,7 @@ __pthread_mutex_lock (mutex) mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exit here. If we fall through to the end of the function __nusers would be @@ -149,18 +158,23 @@ __pthread_mutex_lock (mutex) return EOWNERDEAD; } - normal: /* Check whether we already hold the mutex. */ - if (__builtin_expect ((mutex->__data.__lock & FUTEX_TID_MASK) - == id, 0)) + if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP) - return EDEADLK; + == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + NULL); + return EDEADLK; + } if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP) + == PTHREAD_MUTEX_ROBUST_RECURSIVE_NP) { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + NULL); + /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ @@ -180,6 +194,7 @@ __pthread_mutex_lock (mutex) /* This mutex is now not recoverable. */ mutex->__data.__count = 0; lll_mutex_unlock (mutex->__data.__lock); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } } @@ -187,6 +202,7 @@ __pthread_mutex_lock (mutex) mutex->__data.__count = 1; ENQUEUE_MUTEX (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; default: diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c index b69caedc7c..7c48c7ce6b 100644 --- a/nptl/pthread_mutex_timedlock.c +++ b/nptl/pthread_mutex_timedlock.c @@ -103,25 +103,27 @@ pthread_mutex_timedlock (mutex, abstime) } break; - case PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ADAPTIVE_NP: + case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: + case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: + case PTHREAD_MUTEX_ROBUST_NORMAL_NP: + case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + &mutex->__data.__list.__next); + oldval = mutex->__data.__lock; do { + again: if ((oldval & FUTEX_OWNER_DIED) != 0) { /* The previous owner died. Try locking the mutex. */ - int newval; - while ((newval - = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - id, oldval)) - != oldval) + int newval + = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, + id, oldval); + if (newval != oldval) { - if ((newval & FUTEX_OWNER_DIED) == 0) - goto normal; oldval = newval; + goto again; } /* We got the mutex. */ @@ -130,6 +132,7 @@ pthread_mutex_timedlock (mutex, abstime) mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exist here. If we fall through to the end of the function __nusers would be @@ -138,18 +141,23 @@ pthread_mutex_timedlock (mutex, abstime) return EOWNERDEAD; } - normal: /* Check whether we already hold the mutex. */ - if (__builtin_expect ((mutex->__data.__lock & FUTEX_TID_MASK) - == id, 0)) + if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP) - return EDEADLK; + == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + NULL); + return EDEADLK; + } if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP) + == PTHREAD_MUTEX_ROBUST_RECURSIVE_NP) { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + NULL); + /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ @@ -170,6 +178,7 @@ pthread_mutex_timedlock (mutex, abstime) /* This mutex is now not recoverable. */ mutex->__data.__count = 0; lll_mutex_unlock (mutex->__data.__lock); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } @@ -182,6 +191,7 @@ pthread_mutex_timedlock (mutex, abstime) mutex->__data.__count = 1; ENQUEUE_MUTEX (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; default: diff --git a/nptl/pthread_mutex_trylock.c b/nptl/pthread_mutex_trylock.c index 5a13ea6925..148a6e919f 100644 --- a/nptl/pthread_mutex_trylock.c +++ b/nptl/pthread_mutex_trylock.c @@ -77,25 +77,28 @@ __pthread_mutex_trylock (mutex) return 0; - case PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ADAPTIVE_NP: + case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: + case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: + case PTHREAD_MUTEX_ROBUST_NORMAL_NP: + case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + &mutex->__data.__list.__next); + oldval = mutex->__data.__lock; do { + again: if ((oldval & FUTEX_OWNER_DIED) != 0) { /* The previous owner died. Try locking the mutex. */ - int newval; - while ((newval - = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - id, oldval)) - != oldval) + int newval + = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, + id, oldval); + + if (newval != oldval) { - if ((newval & FUTEX_OWNER_DIED) == 0) - goto normal; oldval = newval; + goto again; } /* We got the mutex. */ @@ -104,6 +107,7 @@ __pthread_mutex_trylock (mutex) mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exist here. If we fall through to the end of the function __nusers would be @@ -112,18 +116,23 @@ __pthread_mutex_trylock (mutex) return EOWNERDEAD; } - normal: /* Check whether we already hold the mutex. */ - if (__builtin_expect ((mutex->__data.__lock & FUTEX_TID_MASK) - == id, 0)) + if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP) - return EDEADLK; + == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + NULL); + return EDEADLK; + } if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP) + == PTHREAD_MUTEX_ROBUST_RECURSIVE_NP) { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + NULL); + /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ @@ -137,7 +146,11 @@ __pthread_mutex_trylock (mutex) oldval = lll_robust_mutex_trylock (mutex->__data.__lock, id); if (oldval != 0 && (oldval & FUTEX_OWNER_DIED) == 0) - return EBUSY; + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + + return EBUSY; + } robust: if (__builtin_expect (mutex->__data.__owner @@ -147,12 +160,14 @@ __pthread_mutex_trylock (mutex) mutex->__data.__count = 0; if (oldval == id) lll_mutex_unlock (mutex->__data.__lock); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } } while ((oldval & FUTEX_OWNER_DIED) != 0); ENQUEUE_MUTEX (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); mutex->__data.__owner = id; ++mutex->__data.__nusers; diff --git a/nptl/pthread_mutex_unlock.c b/nptl/pthread_mutex_unlock.c index d41eefe34c..bf9aa7625f 100644 --- a/nptl/pthread_mutex_unlock.c +++ b/nptl/pthread_mutex_unlock.c @@ -63,10 +63,12 @@ __pthread_mutex_unlock_usercnt (mutex, decr) lll_mutex_unlock (mutex->__data.__lock); break; - case PTHREAD_MUTEX_ROBUST_PRIVATE_RECURSIVE_NP: + case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: /* Recursive mutex. */ if ((mutex->__data.__lock & FUTEX_TID_MASK) - == THREAD_GETMEM (THREAD_SELF, tid)) + == THREAD_GETMEM (THREAD_SELF, tid) + && __builtin_expect (mutex->__data.__owner + == PTHREAD_MUTEX_INCONSISTENT, 0)) { if (--mutex->__data.__count != 0) /* We still hold the mutex. */ @@ -84,9 +86,9 @@ __pthread_mutex_unlock_usercnt (mutex, decr) goto robust; - case PTHREAD_MUTEX_ROBUST_PRIVATE_ERRORCHECK_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_NP: - case PTHREAD_MUTEX_ROBUST_PRIVATE_ADAPTIVE_NP: + case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: + case PTHREAD_MUTEX_ROBUST_NORMAL_NP: + case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: if ((mutex->__data.__lock & FUTEX_TID_MASK) != THREAD_GETMEM (THREAD_SELF, tid) || ! lll_mutex_islocked (mutex->__data.__lock)) @@ -102,6 +104,8 @@ __pthread_mutex_unlock_usercnt (mutex, decr) robust: /* Remove mutex from the list. */ + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + &mutex->__data.__list.__next); DEQUEUE_MUTEX (mutex); mutex->__data.__owner = newowner; @@ -111,6 +115,8 @@ __pthread_mutex_unlock_usercnt (mutex, decr) /* Unlock. */ lll_robust_mutex_unlock (mutex->__data.__lock); + + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; default: diff --git a/nptl/tst-robust8.c b/nptl/tst-robust8.c new file mode 100644 index 0000000000..19682e594f --- /dev/null +++ b/nptl/tst-robust8.c @@ -0,0 +1,264 @@ +#include <pthread.h> +#include <signal.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/mman.h> +#include <sys/wait.h> + + + + +static void prepare (void); +#define PREPARE(argc, argv) prepare () +static int do_test (void); +#define TEST_FUNCTION do_test () +#define TIMEOUT 3 +#include "../test-skeleton.c" + + +static int fd; +#define N 100 + +static void +prepare (void) +{ + fd = create_temp_file ("tst-robust8", NULL); + if (fd == -1) + exit (1); +} + + +#define THESIGNAL SIGKILL +#define ROUNDS 5 +#define THREADS 9 + + +static const struct timespec before = { 0, 0 }; + + +static pthread_mutex_t *map; + + +static void * +tf (void *arg) +{ + long int nr = (long int) arg; + int fct = nr % 3; + + uint8_t state[N]; + memset (state, '\0', sizeof (state)); + + while (1) + { + int r = random () % N; + if (state[r] == 0) + { + int e; + + switch (fct) + { + case 0: + e = pthread_mutex_lock (&map[r]); + if (e != 0) + { + printf ("mutex_lock of %d in thread %ld failed with %d\n", + r, nr, e); + exit (1); + } + state[r] = 1; + break; + case 1: + e = pthread_mutex_timedlock (&map[r], &before); + if (e != 0 && e != ETIMEDOUT) + { + printf ("\ +mutex_timedlock of %d in thread %ld failed with %d\n", + r, nr, e); + exit (1); + } + break; + default: + e = pthread_mutex_trylock (&map[r]); + if (e != 0 && e != EBUSY) + { + printf ("mutex_trylock of %d in thread %ld failed with %d\n", + r, nr, e); + exit (1); + } + break; + } + + if (e == EOWNERDEAD) + pthread_mutex_consistent_np (&map[r]); + + if (e == 0 || e == EOWNERDEAD) + state[r] = 1; + } + else + { + int e = pthread_mutex_unlock (&map[r]); + if (e != 0) + { + printf ("mutex_unlock of %d in thread %ld failed with %d\n", + r, nr, e); + exit (1); + } + + state[r] = 0; + } + } +} + + +static void +child (int round) +{ + for (int thread = 1; thread <= THREADS; ++thread) + { + pthread_t th; + if (pthread_create (&th, NULL, tf, (void *) (long int) thread) != 0) + { + printf ("cannot create thread %d in round %d\n", thread, round); + exit (1); + } + } + + struct timespec ts; + ts.tv_sec = 0; + ts.tv_nsec = 1000000000 / ROUNDS; + while (nanosleep (&ts, &ts) != 0) + /* nothing */; + + /* Time to die. */ + kill (getpid (), THESIGNAL); + + /* We better never get here. */ + abort (); +} + + +static int +do_test (void) +{ + if (ftruncate (fd, N * sizeof (pthread_mutex_t)) != 0) + { + puts ("cannot size new file"); + return 1; + } + + map = mmap (NULL, N * sizeof (pthread_mutex_t), PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (map == MAP_FAILED) + { + puts ("mapping failed"); + return 1; + } + + pthread_mutexattr_t ma; + if (pthread_mutexattr_init (&ma) != 0) + { + puts ("mutexattr_init failed"); + return 0; + } + if (pthread_mutexattr_setrobust_np (&ma, PTHREAD_MUTEX_ROBUST_NP) != 0) + { + puts ("mutexattr_setrobust failed"); + return 1; + } + if (pthread_mutexattr_setpshared (&ma, PTHREAD_PROCESS_SHARED) != 0) + { + puts ("mutexattr_setpshared failed"); + return 1; + } + + for (int round = 1; round <= ROUNDS; ++round) + { + for (int n = 0; n < N; ++n) + { + int e = pthread_mutex_init (&map[n], &ma); + if (e == ENOTSUP) + { + puts ("cannot support pshared robust mutexes"); + return 0; + } + if (e != 0) + { + printf ("mutex_init %d in round %d failed\n", n + 1, round); + return 1; + } + } + + pid_t p = fork (); + if (p == -1) + { + printf ("fork in round %d failed\n", round); + return 1; + } + if (p == 0) + child (round); + + int status; + if (TEMP_FAILURE_RETRY (waitpid (p, &status, 0)) != p) + { + printf ("waitpid in round %d failed\n", round); + return 1; + } + if (!WIFSIGNALED (status)) + { + printf ("child did not die of a signal in round %d\n", round); + return 1; + } + if (WTERMSIG (status) != THESIGNAL) + { + printf ("child did not die of signal %d in round %d\n", + THESIGNAL, round); + return 1; + } + + for (int n = 0; n < N; ++n) + { + int e = pthread_mutex_lock (&map[n]); + if (e != 0 && e != EOWNERDEAD) + { + printf ("mutex_lock %d failed in round %d\n", n + 1, round); + return 1; + } + } + + for (int n = 0; n < N; ++n) + if (pthread_mutex_unlock (&map[n]) != 0) + { + printf ("mutex_unlock %d failed in round %d\n", n + 1, round); + return 1; + } + + for (int n = 0; n < N; ++n) + { + int e = pthread_mutex_destroy (&map[n]); + if (e != 0) + { + printf ("mutex_destroy %d in round %d failed with %d\n", + n + 1, round, e); + printf("nusers = %d\n", (int) map[n].__data.__nusers); + return 1; + } + } + } + + if (pthread_mutexattr_destroy (&ma) != 0) + { + puts ("mutexattr_destroy failed"); + return 1; + } + + if (munmap (map, N * sizeof (pthread_mutex_t)) != 0) + { + puts ("munmap failed"); + return 1; + } + + return 0; +} diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index 53eeee90ec..710de2e226 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -468,3 +468,9 @@ && (defined __i386__ || defined __x86_64__) # define __ASSUME_ATFCTS 1 #endif + +/* Support for inter-process robust mutexes was added in 2.6.17. */ +#if __LINUX_KERNEL_VERSION >= 0x020611 \ + && (defined __i386__ || defined __x86_64__) +# define __ASSUME_SET_ROBUST_LIST 1 +#endif |