From 4dcb50723aa0d3f4264ee1d9ca3baf70b4adc2de Mon Sep 17 00:00:00 2001 From: davidxu Date: Wed, 1 Sep 2010 02:18:33 +0000 Subject: [PATCH] Add signal handler wrapper, the reason to add it becauses there are some cases we want to improve: 1) if a thread signal got a signal while in cancellation point, it is possible the TDP_WAKEUP may be eaten by signal handler if the handler called some interruptibly system calls. 2) In signal handler, we want to disable cancellation. 3) When thread holding some low level locks, it is better to disable signal, those code need not to worry reentrancy, sigprocmask system call is avoided because it is a bit expensive. The signal handler wrapper works in this way: 1) libthr installs its signal handler if user code invokes sigaction to install its handler, the user handler is recorded in internal array. 2) when a signal is delivered, libthr's signal handler is invoke, libthr checks if thread holds some low level lock or is in critical region, if it is true, the signal is buffered, and all signals are masked, once the thread leaves critical region, correct signal mask is restored and buffered signal is processed. 3) before user signal handler is invoked, cancellation is temporarily disabled, after user signal handler is returned, cancellation state is restored, and pending cancellation is rescheduled. --- lib/libthr/thread/thr_cancel.c | 41 +-- lib/libthr/thread/thr_cond.c | 4 +- lib/libthr/thread/thr_create.c | 13 - lib/libthr/thread/thr_exit.c | 19 ++ lib/libthr/thread/thr_fork.c | 6 + lib/libthr/thread/thr_init.c | 8 +- lib/libthr/thread/thr_join.c | 4 +- lib/libthr/thread/thr_kern.c | 32 -- lib/libthr/thread/thr_private.h | 33 +- lib/libthr/thread/thr_rtld.c | 13 +- lib/libthr/thread/thr_sig.c | 518 +++++++++++++++++++++++++------ lib/libthr/thread/thr_syscalls.c | 129 ++++---- lib/libthr/thread/thr_umtx.c | 39 +++ lib/libthr/thread/thr_umtx.h | 5 + 14 files changed, 591 insertions(+), 273 deletions(-) diff --git a/lib/libthr/thread/thr_cancel.c b/lib/libthr/thread/thr_cancel.c index 943d53c39e9..e408e03dbcd 100644 --- a/lib/libthr/thread/thr_cancel.c +++ b/lib/libthr/thread/thr_cancel.c @@ -85,14 +85,11 @@ _pthread_setcancelstate(int state, int *oldstate) oldval = curthread->cancel_enable; switch (state) { case PTHREAD_CANCEL_DISABLE: - THR_LOCK(curthread); curthread->cancel_enable = 0; - THR_UNLOCK(curthread); break; case PTHREAD_CANCEL_ENABLE: - THR_LOCK(curthread); curthread->cancel_enable = 1; - THR_UNLOCK(curthread); + testcancel(curthread); break; default: return (EINVAL); @@ -136,23 +133,22 @@ _pthread_testcancel(void) { struct pthread *curthread = _get_curthread(); - _thr_cancel_enter(curthread); - _thr_cancel_leave(curthread); + curthread->cancel_point = 1; + testcancel(curthread); + curthread->cancel_point = 0; } void _thr_cancel_enter(struct pthread *curthread) { - curthread->cancel_point++; - if (curthread->cancel_enable) - testcancel(curthread); + curthread->cancel_point = 1; + testcancel(curthread); } void -_thr_cancel_enter_defer(struct pthread *curthread, int maycancel) +_thr_cancel_enter2(struct pthread *curthread, int maycancel) { - curthread->cancel_defer++; - curthread->cancel_point++; + curthread->cancel_point = 1; if (__predict_false(SHOULD_CANCEL(curthread) && !THR_IN_CRITICAL(curthread))) { if (!maycancel) @@ -163,24 +159,9 @@ _thr_cancel_enter_defer(struct pthread *curthread, int maycancel) } void -_thr_cancel_leave(struct pthread *curthread) -{ - curthread->cancel_point--; -} - -void -_thr_cancel_leave2(struct pthread *curthread, int maycancel) -{ - if (curthread->cancel_enable && maycancel) - testcancel(curthread); - curthread->cancel_point--; -} - -void -_thr_cancel_leave_defer(struct pthread *curthread, int maycancel) +_thr_cancel_leave(struct pthread *curthread, int maycancel) { - if (curthread->cancel_enable && maycancel) + if (maycancel) testcancel(curthread); - curthread->cancel_point--; - curthread->cancel_defer--; + curthread->cancel_point = 0; } diff --git a/lib/libthr/thread/thr_cond.c b/lib/libthr/thread/thr_cond.c index 95970d9d0fc..07f1b8b952c 100644 --- a/lib/libthr/thread/thr_cond.c +++ b/lib/libthr/thread/thr_cond.c @@ -210,10 +210,10 @@ cond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex, if (cancel) { THR_CLEANUP_PUSH(curthread, cond_cancel_handler, &info); - _thr_cancel_enter_defer(curthread, 0); + _thr_cancel_enter2(curthread, 0); ret = _thr_ucond_wait(&cv->c_kerncv, &cv->c_lock, tsp, 1); info.cond = NULL; - _thr_cancel_leave_defer(curthread, (ret != 0)); + _thr_cancel_leave(curthread, (ret != 0)); THR_CLEANUP_POP(curthread, 0); } else { ret = _thr_ucond_wait(&cv->c_kerncv, &cv->c_lock, tsp, 0); diff --git a/lib/libthr/thread/thr_create.c b/lib/libthr/thread/thr_create.c index f73a6c9231b..2677571b424 100644 --- a/lib/libthr/thread/thr_create.c +++ b/lib/libthr/thread/thr_create.c @@ -127,11 +127,6 @@ _pthread_create(pthread_t * thread, const pthread_attr_t * attr, if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) new_thread->tlflags |= TLFLAGS_DETACHED; - if (curthread->in_sigcancel_handler) - new_thread->unblock_sigcancel = 1; - else - new_thread->unblock_sigcancel = 0; - /* Add the new thread. */ new_thread->refcount = 1; _thr_link(curthread, new_thread); @@ -263,14 +258,6 @@ thread_start(struct pthread *curthread) if (curthread->force_exit) _pthread_exit(PTHREAD_CANCELED); - if (curthread->unblock_sigcancel) { - sigset_t set1; - - SIGEMPTYSET(set1); - SIGADDSET(set1, SIGCANCEL); - __sys_sigprocmask(SIG_UNBLOCK, &set1, NULL); - } - if (curthread->attr.suspend == THR_CREATE_SUSPENDED) { #if 0 /* Done in THR_UNLOCK() */ diff --git a/lib/libthr/thread/thr_exit.c b/lib/libthr/thread/thr_exit.c index e6facd9d85b..10581ab2395 100644 --- a/lib/libthr/thread/thr_exit.c +++ b/lib/libthr/thread/thr_exit.c @@ -34,6 +34,8 @@ #include #include #include +#include +#include #include "un-namespace.h" #include "libc_private.h" @@ -57,6 +59,12 @@ _thread_exit(const char *fname, int lineno, const char *msg) void _pthread_exit(void *status) +{ + _pthread_exit_mask(status, NULL); +} + +void +_pthread_exit_mask(void *status, sigset_t *mask) { struct pthread *curthread = _get_curthread(); @@ -73,6 +81,17 @@ _pthread_exit(void *status) curthread->cancelling = 1; curthread->cancel_enable = 0; curthread->cancel_async = 0; + curthread->cancel_point = 0; + if (mask != NULL) + __sys_sigprocmask(SIG_SETMASK, mask, NULL); + if (curthread->unblock_sigcancel) { + sigset_t set; + + curthread->unblock_sigcancel = 0; + SIGEMPTYSET(set); + SIGADDSET(set, SIGCANCEL); + __sys_sigprocmask(SIG_UNBLOCK, mask, NULL); + } /* Save the return value: */ curthread->ret = status; diff --git a/lib/libthr/thread/thr_fork.c b/lib/libthr/thread/thr_fork.c index f20942d42be..8e1ea6a5e72 100644 --- a/lib/libthr/thread/thr_fork.c +++ b/lib/libthr/thread/thr_fork.c @@ -115,6 +115,7 @@ __pthread_cxa_finalize(struct dl_phdr_info *phdr_info) } THR_UMUTEX_UNLOCK(curthread, &_thr_atfork_lock); _thr_tsd_unload(phdr_info); + _thr_sigact_unload(phdr_info); } __weak_reference(_fork, fork); @@ -161,6 +162,7 @@ _fork(void) * Block all signals until we reach a safe point. */ _thr_signal_block(curthread); + _thr_signal_prefork(); /* Fork a new process: */ if ((ret = __sys_fork()) == 0) { @@ -182,6 +184,8 @@ _fork(void) _thr_umutex_init(&curthread->lock); _thr_umutex_init(&_thr_atfork_lock); + _thr_signal_postfork_child(); + if (was_threaded) _rtld_atfork_post(rtld_locks); _thr_setthreaded(0); @@ -211,6 +215,8 @@ _fork(void) /* Parent process */ errsave = errno; + _thr_signal_postfork(); + /* Ready to continue, unblock signals. */ _thr_signal_unblock(curthread); diff --git a/lib/libthr/thread/thr_init.c b/lib/libthr/thread/thr_init.c index 1bfdd287c20..ea567ee9958 100644 --- a/lib/libthr/thread/thr_init.c +++ b/lib/libthr/thread/thr_init.c @@ -289,7 +289,6 @@ void _libpthread_init(struct pthread *curthread) { int fd, first = 0; - sigset_t sigset, oldset; /* Check if this function has already been called: */ if ((_thr_initial != NULL) && (curthread == NULL)) @@ -347,13 +346,8 @@ _libpthread_init(struct pthread *curthread) _tcb_set(curthread->tcb); if (first) { - SIGFILLSET(sigset); - SIGDELSET(sigset, SIGTRAP); - __sys_sigprocmask(SIG_SETMASK, &sigset, &oldset); - _thr_signal_init(); _thr_initial = curthread; - SIGDELSET(oldset, SIGCANCEL); - __sys_sigprocmask(SIG_SETMASK, &oldset, NULL); + _thr_signal_init(); if (_thread_event_mask & TD_CREATE) _thr_report_creation(curthread, curthread); } diff --git a/lib/libthr/thread/thr_join.c b/lib/libthr/thread/thr_join.c index 8201abafeae..d3c8367dc13 100644 --- a/lib/libthr/thread/thr_join.c +++ b/lib/libthr/thread/thr_join.c @@ -107,7 +107,7 @@ join_common(pthread_t pthread, void **thread_return, THREAD_LIST_UNLOCK(curthread); THR_CLEANUP_PUSH(curthread, backout_join, pthread); - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); tid = pthread->tid; while (pthread->tid != TID_TERMINATED) { @@ -127,7 +127,7 @@ join_common(pthread_t pthread, void **thread_return, break; } - _thr_cancel_leave_defer(curthread, 0); + _thr_cancel_leave(curthread, 0); THR_CLEANUP_POP(curthread, 0); if (ret == ETIMEDOUT) { diff --git a/lib/libthr/thread/thr_kern.c b/lib/libthr/thread/thr_kern.c index 649a973aabd..3ad33ad995a 100644 --- a/lib/libthr/thread/thr_kern.c +++ b/lib/libthr/thread/thr_kern.c @@ -60,38 +60,6 @@ _thr_setthreaded(int threaded) return (0); } -void -_thr_signal_block(struct pthread *curthread) -{ - sigset_t set; - - if (curthread->sigblock > 0) { - curthread->sigblock++; - return; - } - SIGFILLSET(set); - SIGDELSET(set, SIGBUS); - SIGDELSET(set, SIGILL); - SIGDELSET(set, SIGFPE); - SIGDELSET(set, SIGSEGV); - SIGDELSET(set, SIGTRAP); - __sys_sigprocmask(SIG_BLOCK, &set, &curthread->sigmask); - curthread->sigblock++; -} - -void -_thr_signal_unblock(struct pthread *curthread) -{ - if (--curthread->sigblock == 0) - __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); -} - -int -_thr_send_sig(struct pthread *thread, int sig) -{ - return thr_kill(thread->tid, sig); -} - void _thr_assert_lock_level() { diff --git a/lib/libthr/thread/thr_private.h b/lib/libthr/thread/thr_private.h index f261810e7e9..492d58d2063 100644 --- a/lib/libthr/thread/thr_private.h +++ b/lib/libthr/thread/thr_private.h @@ -376,12 +376,21 @@ struct pthread { /* Thread temporary signal mask. */ sigset_t sigmask; - /* Thread is in SIGCANCEL handler. */ - int in_sigcancel_handler; - - /* New thread should unblock SIGCANCEL. */ + /* Thread should unblock SIGCANCEL. */ int unblock_sigcancel; + /* In sigsuspend state */ + int in_sigsuspend; + + /* deferred signal info */ + siginfo_t deferred_siginfo; + + /* signal mask to restore. */ + sigset_t deferred_sigmask; + + /* the sigaction should be used for deferred signal. */ + struct sigaction deferred_sigact; + /* Force new thread to exit. */ int force_exit; @@ -629,6 +638,7 @@ void _thr_ref_delete_unlocked(struct pthread *, struct pthread *) __hidden; int _thr_find_thread(struct pthread *, struct pthread *, int) __hidden; void _thr_rtld_init(void) __hidden; void _thr_rtld_fini(void) __hidden; +void _thr_rtld_postfork_child(void) __hidden; int _thr_stack_alloc(struct pthread_attr *) __hidden; void _thr_stack_free(struct pthread_attr *) __hidden; void _thr_free(struct pthread *, struct pthread *) __hidden; @@ -637,10 +647,8 @@ void _thread_cleanupspecific(void) __hidden; void _thread_printf(int, const char *, ...) __hidden; void _thr_spinlock_init(void) __hidden; void _thr_cancel_enter(struct pthread *) __hidden; -void _thr_cancel_leave(struct pthread *) __hidden; -void _thr_cancel_leave2(struct pthread *, int) __hidden; -void _thr_cancel_enter_defer(struct pthread *, int) __hidden; -void _thr_cancel_leave_defer(struct pthread *, int) __hidden; +void _thr_cancel_enter2(struct pthread *, int) __hidden; +void _thr_cancel_leave(struct pthread *, int) __hidden; void _thr_testcancel(struct pthread *) __hidden; void _thr_signal_block(struct pthread *) __hidden; void _thr_signal_unblock(struct pthread *) __hidden; @@ -653,7 +661,6 @@ void _thr_hash_remove(struct pthread *) __hidden; struct pthread *_thr_hash_find(struct pthread *) __hidden; void _thr_link(struct pthread *, struct pthread *) __hidden; void _thr_unlink(struct pthread *, struct pthread *) __hidden; -void _thr_suspend_check(struct pthread *) __hidden; void _thr_assert_lock_level(void) __hidden __dead2; void _thr_ast(struct pthread *) __hidden; void _thr_once_init(void) __hidden; @@ -662,6 +669,9 @@ void _thr_report_creation(struct pthread *curthread, void _thr_report_death(struct pthread *curthread) __hidden; int _thr_getscheduler(lwpid_t, int *, struct sched_param *) __hidden; int _thr_setscheduler(lwpid_t, int, const struct sched_param *) __hidden; +void _thr_signal_prefork(void) __hidden; +void _thr_signal_postfork(void) __hidden; +void _thr_signal_postfork_child(void) __hidden; int _rtp_to_schedparam(const struct rtprio *rtp, int *policy, struct sched_param *param) __hidden; int _schedparam_to_rtp(int policy, const struct sched_param *param, @@ -672,6 +682,8 @@ int _sched_yield(void); void _pthread_cleanup_push(void (*)(void *), void *); void _pthread_cleanup_pop(int); +void _pthread_exit_mask(void *status, sigset_t *mask) __dead2 __hidden; + /* #include */ #ifdef _SYS_FCNTL_H_ @@ -687,7 +699,7 @@ int __sys_sigaction(int, const struct sigaction *, struct sigaction *); int __sys_sigpending(sigset_t *); int __sys_sigprocmask(int, const sigset_t *, sigset_t *); int __sys_sigsuspend(const sigset_t *); -int __sys_sigreturn(ucontext_t *); +int __sys_sigreturn(const ucontext_t *); int __sys_sigaltstack(const struct sigaltstack *, struct sigaltstack *); int __sys_sigwait(const sigset_t *, int *); int __sys_sigtimedwait(const sigset_t *, siginfo_t *, @@ -740,6 +752,7 @@ _thr_check_init(void) struct dl_phdr_info; void __pthread_cxa_finalize(struct dl_phdr_info *phdr_info); void _thr_tsd_unload(struct dl_phdr_info *phdr_info) __hidden; +void _thr_sigact_unload(struct dl_phdr_info *phdr_info) __hidden; __END_DECLS diff --git a/lib/libthr/thread/thr_rtld.c b/lib/libthr/thread/thr_rtld.c index d9041adcfb9..e6af7029c76 100644 --- a/lib/libthr/thread/thr_rtld.c +++ b/lib/libthr/thread/thr_rtld.c @@ -32,6 +32,7 @@ */ #include #include +#include #include "rtld_lock.h" #include "thr_private.h" @@ -132,7 +133,7 @@ _thr_rtld_wlock_acquire(void *lock) SAVE_ERRNO(); l = (struct rtld_lock *)lock; - _thr_signal_block(curthread); + THR_CRITICAL_ENTER(curthread); while (_thr_rwlock_wrlock(&l->lock, NULL) != 0) ; RESTORE_ERRNO(); @@ -152,12 +153,9 @@ _thr_rtld_lock_release(void *lock) state = l->lock.rw_state; if (_thr_rwlock_unlock(&l->lock) == 0) { - if ((state & URWLOCK_WRITE_OWNER) == 0) { + if ((state & URWLOCK_WRITE_OWNER) == 0) curthread->rdlock_count--; - THR_CRITICAL_LEAVE(curthread); - } else { - _thr_signal_unblock(curthread); - } + THR_CRITICAL_LEAVE(curthread); } RESTORE_ERRNO(); } @@ -193,6 +191,9 @@ _thr_rtld_init(void) /* force to resolve errno() PLT */ __error(); + /* force to resolve memcpy PLT */ + memcpy(&dummy, &dummy, sizeof(dummy)); + li.lock_create = _thr_rtld_lock_create; li.lock_destroy = _thr_rtld_lock_destroy; li.rlock_acquire = _thr_rtld_rlock_acquire; diff --git a/lib/libthr/thread/thr_sig.c b/lib/libthr/thread/thr_sig.c index 312c15f4a3b..382ff4fbbab 100644 --- a/lib/libthr/thread/thr_sig.c +++ b/lib/libthr/thread/thr_sig.c @@ -32,11 +32,10 @@ #include #include #include -#include -#include #include #include #include "un-namespace.h" +#include "libc_private.h" #include "thr_private.h" @@ -47,7 +46,19 @@ #define DBG_MSG(x...) #endif -extern int __pause(void); +struct usigaction { + struct sigaction sigact; + struct urwlock lock; +}; + +static struct usigaction _thr_sigact[_SIG_MAXSIG]; + +static void thr_sighandler(int, siginfo_t *, void *); +static void handle_signal(struct sigaction *, int, siginfo_t *, ucontext_t *); +static void check_deferred_signal(struct pthread *); +static void check_suspend(struct pthread *); +static void check_cancel(struct pthread *curthread, ucontext_t *ucp); + int ___pause(void); int _raise(int); int __sigtimedwait(const sigset_t *set, siginfo_t *info, @@ -59,10 +70,49 @@ int _sigwaitinfo(const sigset_t *set, siginfo_t *info); int __sigwait(const sigset_t *set, int *sig); int _sigwait(const sigset_t *set, int *sig); int __sigsuspend(const sigset_t *sigmask); +int _sigaction(int, const struct sigaction *, struct sigaction *); int _setcontext(const ucontext_t *); int _swapcontext(ucontext_t *, const ucontext_t *); -static void +static const sigset_t _thr_deferset={{ + 0xffffffff & ~(_SIG_BIT(SIGBUS)|_SIG_BIT(SIGILL)|_SIG_BIT(SIGFPE)| + _SIG_BIT(SIGSEGV)|_SIG_BIT(SIGTRAP)|_SIG_BIT(SIGSYS)), + 0xffffffff, + 0xffffffff, + 0xffffffff}}; + +static const sigset_t _thr_maskset={{ + 0xffffffff, + 0xffffffff, + 0xffffffff, + 0xffffffff}}; + +void +_thr_signal_block(struct pthread *curthread) +{ + + if (curthread->sigblock > 0) { + curthread->sigblock++; + return; + } + __sys_sigprocmask(SIG_BLOCK, &_thr_maskset, &curthread->sigmask); + curthread->sigblock++; +} + +void +_thr_signal_unblock(struct pthread *curthread) +{ + if (--curthread->sigblock == 0) + __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); +} + +int +_thr_send_sig(struct pthread *thread, int sig) +{ + return thr_kill(thread->tid, sig); +} + +static inline void remove_thr_signals(sigset_t *set) { if (SIGISMEMBER(*set, SIGCANCEL)) @@ -72,87 +122,244 @@ remove_thr_signals(sigset_t *set) static const sigset_t * thr_remove_thr_signals(const sigset_t *set, sigset_t *newset) { - const sigset_t *pset; - - if (SIGISMEMBER(*set, SIGCANCEL)) { - *newset = *set; - SIGDELSET(*newset, SIGCANCEL); - pset = newset; - } else - pset = set; - return (pset); + *newset = *set; + remove_thr_signals(newset); + return (newset); } static void sigcancel_handler(int sig __unused, - siginfo_t *info __unused, ucontext_t *ucp __unused) + siginfo_t *info __unused, ucontext_t *ucp) { struct pthread *curthread = _get_curthread(); + int err; - curthread->in_sigcancel_handler++; - _thr_ast(curthread); - curthread->in_sigcancel_handler--; + if (THR_IN_CRITICAL(curthread)) + return; + err = errno; + check_suspend(curthread); + check_cancel(curthread, ucp); + errno = err; +} + +typedef void (*ohandler)(int sig, int code, + struct sigcontext *scp, char *addr, __sighandler_t *catcher); + +/* + * The signal handler wrapper is entered with all signal masked. + */ +static void +thr_sighandler(int sig, siginfo_t *info, void *_ucp) +{ + struct pthread *curthread = _get_curthread(); + ucontext_t *ucp = _ucp; + struct sigaction act; + int err; + + err = errno; + _thr_rwl_rdlock(&_thr_sigact[sig-1].lock); + act = _thr_sigact[sig-1].sigact; + _thr_rwl_unlock(&_thr_sigact[sig-1].lock); + errno = err; + + /* + * if a thread is in critical region, for example it holds low level locks, + * try to defer the signal processing, however if the signal is synchronous + * signal, it means a bad thing has happened, this is a programming error, + * resuming fault point can not help anything (normally causes deadloop), + * so here we let user code handle it immediately. + */ + if (THR_IN_CRITICAL(curthread) && SIGISMEMBER(_thr_deferset, sig)) { + memcpy(&curthread->deferred_sigact, &act, sizeof(struct sigaction)); + memcpy(&curthread->deferred_siginfo, info, sizeof(siginfo_t)); + curthread->deferred_sigmask = ucp->uc_sigmask; + /* mask all signals, we will restore it later. */ + ucp->uc_sigmask = _thr_deferset; + return; + } + + handle_signal(&act, sig, info, ucp); +} + +static void +handle_signal(struct sigaction *actp, int sig, siginfo_t *info, ucontext_t *ucp) +{ + struct pthread *curthread = _get_curthread(); + ucontext_t uc2; + __siginfohandler_t *sigfunc; + int cancel_defer; + int cancel_point; + int cancel_async; + int cancel_enable; + int in_sigsuspend; + int err; + + /* add previous level mask */ + SIGSETOR(actp->sa_mask, ucp->uc_sigmask); + + /* add this signal's mask */ + if (!(actp->sa_flags & SA_NODEFER)) + SIGADDSET(actp->sa_mask, sig); + + in_sigsuspend = curthread->in_sigsuspend; + curthread->in_sigsuspend = 0; + + /* + * if thread is in deferred cancellation mode, disable cancellation + * in signal handler. + * if user signal handler calls a cancellation point function, e.g, + * it calls write() to write data to file, because write() is a + * cancellation point, the thread is immediately cancelled if + * cancellation is pending, to avoid this problem while thread is in + * deferring mode, cancellation is temporarily disabled. + */ + cancel_defer = curthread->cancel_defer; + cancel_point = curthread->cancel_point; + cancel_async = curthread->cancel_async; + cancel_enable = curthread->cancel_enable; + curthread->cancel_point = 0; + curthread->cancel_defer = 0; + if (!cancel_async) + curthread->cancel_enable = 0; + + /* restore correct mask before calling user handler */ + __sys_sigprocmask(SIG_SETMASK, &actp->sa_mask, NULL); + + sigfunc = actp->sa_sigaction; + + /* + * We have already reset cancellation point flags, so if user's code + * longjmp()s out of its signal handler, wish its jmpbuf was set + * outside of a cancellation point, in most cases, this would be + * true. however, ther is no way to save cancel_enable in jmpbuf, + * so after setjmps() returns once more, the user code may need to + * re-set cancel_enable flag by calling pthread_setcancelstate(). + */ + if ((actp->sa_flags & SA_SIGINFO) != 0) + (*(sigfunc))(sig, info, ucp); + else { + ((ohandler)(*sigfunc))( + sig, info->si_code, (struct sigcontext *)ucp, + info->si_addr, (__sighandler_t *)sigfunc); + } + err = errno; + + curthread->in_sigsuspend = in_sigsuspend; + curthread->cancel_defer = cancel_defer; + curthread->cancel_point = cancel_point; + curthread->cancel_enable = cancel_enable; + + memcpy(&uc2, ucp, sizeof(uc2)); + SIGDELSET(uc2.uc_sigmask, SIGCANCEL); + + /* reschedule cancellation */ + check_cancel(curthread, &uc2); + errno = err; + __sys_sigreturn(&uc2); } void _thr_ast(struct pthread *curthread) { - if (THR_IN_CRITICAL(curthread)) + if (!THR_IN_CRITICAL(curthread)) { + check_deferred_signal(curthread); + check_suspend(curthread); + check_cancel(curthread, NULL); + } +} + +/* reschedule cancellation */ +static void +check_cancel(struct pthread *curthread, ucontext_t *ucp) +{ + + if (__predict_true(!curthread->cancel_pending || !curthread->cancel_enable || + curthread->cancelling)) return; - if (curthread->cancel_pending && curthread->cancel_enable - && !curthread->cancelling) { - if (curthread->cancel_async) { - /* - * asynchronous cancellation mode, act upon - * immediately. - */ - _pthread_exit(PTHREAD_CANCELED); - } else { - /* - * Otherwise, we are in defer mode, and we are at - * cancel point, tell kernel to not block the current - * thread on next cancelable system call. - * - * There are two cases we should call thr_wake() to - * turn on TDP_WAKEUP in kernel: - * 1) we are going to call a cancelable system call, - * non-zero cancel_point means we are already in - * cancelable state, next system call is cancelable. - * 2) because _thr_ast() may be called by - * THR_CRITICAL_LEAVE() which is used by rtld rwlock - * and any libthr internal locks, when rtld rwlock - * is used, it is mostly caused my an unresolved PLT. - * those routines may clear the TDP_WAKEUP flag by - * invoking some system calls, in those cases, we - * also should reenable the flag. - */ - if (curthread->cancel_point) { - if (curthread->cancel_defer) - thr_wake(curthread->tid); - else - _pthread_exit(PTHREAD_CANCELED); - } + if (curthread->cancel_async) { + /* + * asynchronous cancellation mode, act upon + * immediately. + */ + _pthread_exit_mask(PTHREAD_CANCELED, + ucp? &ucp->uc_sigmask : NULL); + } else { + /* + * Otherwise, we are in defer mode, and we are at + * cancel point, tell kernel to not block the current + * thread on next cancelable system call. + * + * There are three cases we should call thr_wake() to + * turn on TDP_WAKEUP or send SIGCANCEL in kernel: + * 1) we are going to call a cancelable system call, + * non-zero cancel_point means we are already in + * cancelable state, next system call is cancelable. + * 2) because _thr_ast() may be called by + * THR_CRITICAL_LEAVE() which is used by rtld rwlock + * and any libthr internal locks, when rtld rwlock + * is used, it is mostly caused my an unresolved PLT. + * those routines may clear the TDP_WAKEUP flag by + * invoking some system calls, in those cases, we + * also should reenable the flag. + * 3) thread is in sigsuspend(), and the syscall insists + * on getting a signal before it agrees to return. + */ + if (curthread->cancel_point) { + if (curthread->in_sigsuspend && ucp) { + SIGADDSET(ucp->uc_sigmask, SIGCANCEL); + curthread->unblock_sigcancel = 1; + _thr_send_sig(curthread, SIGCANCEL); + } else + thr_wake(curthread->tid); } } +} + +static void +check_deferred_signal(struct pthread *curthread) +{ + ucontext_t uc; + struct sigaction act; + siginfo_t info; + volatile int first; - if (__predict_false((curthread->flags & - (THR_FLAGS_NEED_SUSPEND | THR_FLAGS_SUSPENDED)) - == THR_FLAGS_NEED_SUSPEND)) - _thr_suspend_check(curthread); + if (__predict_true(curthread->deferred_siginfo.si_signo == 0)) + return; + first = 1; + getcontext(&uc); + if (first) { + first = 0; + act = curthread->deferred_sigact; + uc.uc_sigmask = curthread->deferred_sigmask; + memcpy(&info, &curthread->deferred_siginfo, sizeof(siginfo_t)); + /* remove signal */ + curthread->deferred_siginfo.si_signo = 0; + if (act.sa_flags & SA_RESETHAND) { + struct sigaction tact; + + tact = act; + tact.sa_handler = SIG_DFL; + _sigaction(info.si_signo, &tact, NULL); + } + handle_signal(&act, info.si_signo, &info, &uc); + } } -void -_thr_suspend_check(struct pthread *curthread) +static void +check_suspend(struct pthread *curthread) { uint32_t cycle; - int err; + + if (__predict_true((curthread->flags & + (THR_FLAGS_NEED_SUSPEND | THR_FLAGS_SUSPENDED)) + != THR_FLAGS_NEED_SUSPEND)) + return; if (curthread->force_exit) return; - err = errno; /* * Blocks SIGCANCEL which other threads must send. */ @@ -188,15 +395,7 @@ _thr_suspend_check(struct pthread *curthread) THR_UMUTEX_UNLOCK(curthread, &(curthread)->lock); curthread->critical_count--; - /* - * Unblocks SIGCANCEL, it is possible a new SIGCANCEL is ready and - * a new signal frame will nest us, this seems a problem because - * stack will grow and overflow, but because kernel will automatically - * mask the SIGCANCEL when delivering the signal, so we at most only - * have one nesting signal frame, this should be fine. - */ _thr_signal_unblock(curthread); - errno = err; } void @@ -204,11 +403,80 @@ _thr_signal_init(void) { struct sigaction act; - /* Install cancel handler. */ - SIGEMPTYSET(act.sa_mask); - act.sa_flags = SA_SIGINFO | SA_RESTART; + /* Install SIGCANCEL handler. */ + SIGFILLSET(act.sa_mask); + act.sa_flags = SA_SIGINFO; act.sa_sigaction = (__siginfohandler_t *)&sigcancel_handler; __sys_sigaction(SIGCANCEL, &act, NULL); + + /* Unblock SIGCANCEL */ + SIGEMPTYSET(act.sa_mask); + SIGADDSET(act.sa_mask, SIGCANCEL); + __sys_sigprocmask(SIG_UNBLOCK, &act.sa_mask, NULL); +} + +/* + * called from rtld with rtld_lock locked, because rtld_lock is + * a critical region, so all signals have already beeen masked. + */ +void +_thr_sigact_unload(struct dl_phdr_info *phdr_info) +{ + struct urwlock *rwlp; + struct sigaction *actp; + struct sigaction kact; + void (*handler)(int); + int sig; + + for (sig = 1; sig < _SIG_MAXSIG; sig++) { + actp = &_thr_sigact[sig].sigact; +retry: + handler = actp->sa_handler; + if (handler != SIG_DFL && handler != SIG_IGN && + __elf_phdr_match_addr(phdr_info, handler)) { + rwlp = &_thr_sigact[sig].lock; + _thr_rwl_wrlock(rwlp); + if (handler != actp->sa_handler) { + _thr_rwl_unlock(rwlp); + goto retry; + } + actp->sa_handler = SIG_DFL; + actp->sa_flags = SA_SIGINFO; + SIGEMPTYSET(actp->sa_mask); + if (__sys_sigaction(sig, NULL, &kact) == 0 && + kact.sa_handler != SIG_DFL && + kact.sa_handler != SIG_IGN) + __sys_sigaction(sig, actp, NULL); + _thr_rwl_unlock(rwlp); + } + } +} + +void +_thr_signal_prefork(void) +{ + int i; + + for (i = 1; i < _SIG_MAXSIG; ++i) + _thr_rwl_rdlock(&_thr_sigact[i-1].lock); +} + +void +_thr_signal_postfork(void) +{ + int i; + + for (i = 1; i < _SIG_MAXSIG; ++i) + _thr_rwl_unlock(&_thr_sigact[i-1].lock); +} + +void +_thr_signal_postfork_child(void) +{ + int i; + + for (i = 1; i < _SIG_MAXSIG; ++i) + bzero(&_thr_sigact[i-1].lock, sizeof(struct urwlock)); } void @@ -221,14 +489,11 @@ __weak_reference(___pause, pause); int ___pause(void) { - struct pthread *curthread = _get_curthread(); - int ret; + sigset_t oset; - _thr_cancel_enter(curthread); - ret = __pause(); - _thr_cancel_leave(curthread); - - return ret; + if (_sigprocmask(SIG_BLOCK, NULL, &oset) == -1) + return (-1); + return (__sigsuspend(&oset)); } __weak_reference(_raise, raise); @@ -236,13 +501,7 @@ __weak_reference(_raise, raise); int _raise(int sig) { - int ret; - - if (!_thr_isthreaded()) - ret = kill(getpid(), sig); - else - ret = _thr_send_sig(_get_curthread(), sig); - return (ret); + return _thr_send_sig(_get_curthread(), sig); } __weak_reference(_sigaction, sigaction); @@ -250,14 +509,65 @@ __weak_reference(_sigaction, sigaction); int _sigaction(int sig, const struct sigaction * act, struct sigaction * oact) { - /* Check if the signal number is out of range: */ + struct sigaction newact, oldact, oldact2; + sigset_t oldset; + int ret = 0, err = 0; + if (!_SIG_VALID(sig) || sig == SIGCANCEL) { - /* Return an invalid argument: */ errno = EINVAL; return (-1); } - return __sys_sigaction(sig, act, oact); + if (act) + newact = *act; + + __sys_sigprocmask(SIG_SETMASK, &_thr_maskset, &oldset); + _thr_rwl_wrlock(&_thr_sigact[sig-1].lock); + + if (act != NULL) { + oldact2 = _thr_sigact[sig-1].sigact; + + /* + * if a new sig handler is SIG_DFL or SIG_IGN, + * don't remove old handler from _thr_sigact[], + * so deferred signals still can use the handlers, + * multiple threads invoking sigaction itself is + * a race condition, so it is not a problem. + */ + if (newact.sa_handler != SIG_DFL && + newact.sa_handler != SIG_IGN) { + _thr_sigact[sig-1].sigact = newact; + remove_thr_signals( + &_thr_sigact[sig-1].sigact.sa_mask); + newact.sa_flags &= ~SA_NODEFER; + newact.sa_flags |= SA_SIGINFO; + newact.sa_sigaction = thr_sighandler; + newact.sa_mask = _thr_maskset; /* mask all signals */ + } + if ((ret = __sys_sigaction(sig, &newact, &oldact))) { + err = errno; + _thr_sigact[sig-1].sigact = oldact2; + } + } else if (oact != NULL) { + ret = __sys_sigaction(sig, NULL, &oldact); + err = errno; + } + + if (oldact.sa_handler != SIG_DFL && + oldact.sa_handler != SIG_IGN) { + oldact = _thr_sigact[sig-1].sigact; + } + + _thr_rwl_unlock(&_thr_sigact[sig-1].lock); + __sys_sigprocmask(SIG_SETMASK, &oldset, NULL); + + if (ret == 0) { + if (oact != NULL) + *oact = oldact; + } else { + errno = err; + } + return (ret); } __weak_reference(_sigprocmask, sigprocmask); @@ -301,13 +611,24 @@ _sigsuspend(const sigset_t * set) int __sigsuspend(const sigset_t * set) { - struct pthread *curthread = _get_curthread(); + struct pthread *curthread; sigset_t newset; - int ret; + int ret, old; + curthread = _get_curthread(); + + old = curthread->in_sigsuspend; + curthread->in_sigsuspend = 1; _thr_cancel_enter(curthread); ret = __sys_sigsuspend(thr_remove_thr_signals(set, &newset)); - _thr_cancel_leave(curthread); + _thr_cancel_leave(curthread, 1); + curthread->in_sigsuspend = old; + if (curthread->unblock_sigcancel) { + curthread->unblock_sigcancel = 0; + SIGEMPTYSET(newset); + SIGADDSET(newset, SIGCANCEL); + __sys_sigprocmask(SIG_UNBLOCK, &newset, NULL); + } return (ret); } @@ -339,10 +660,10 @@ __sigtimedwait(const sigset_t *set, siginfo_t *info, sigset_t newset; int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_sigtimedwait(thr_remove_thr_signals(set, &newset), info, timeout); - _thr_cancel_leave_defer(curthread, (ret == -1)); + _thr_cancel_leave(curthread, (ret == -1)); return (ret); } @@ -366,9 +687,9 @@ __sigwaitinfo(const sigset_t *set, siginfo_t *info) sigset_t newset; int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_sigwaitinfo(thr_remove_thr_signals(set, &newset), info); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -392,9 +713,9 @@ __sigwait(const sigset_t *set, int *sig) sigset_t newset; int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_sigwait(thr_remove_thr_signals(set, &newset), sig); - _thr_cancel_leave_defer(curthread, (ret != 0)); + _thr_cancel_leave(curthread, (ret != 0)); return (ret); } @@ -404,9 +725,8 @@ _setcontext(const ucontext_t *ucp) { ucontext_t uc; - (void) memcpy(&uc, ucp, sizeof (uc)); + (void) memcpy(&uc, ucp, sizeof(uc)); remove_thr_signals(&uc.uc_sigmask); - return __sys_setcontext(&uc); } @@ -416,7 +736,7 @@ _swapcontext(ucontext_t *oucp, const ucontext_t *ucp) { ucontext_t uc; - (void) memcpy(&uc, ucp, sizeof (uc)); + (void) memcpy(&uc, ucp, sizeof(uc)); remove_thr_signals(&uc.uc_sigmask); return __sys_swapcontext(oucp, &uc); } diff --git a/lib/libthr/thread/thr_syscalls.c b/lib/libthr/thread/thr_syscalls.c index 73fa56fcc8f..2327d7484e6 100644 --- a/lib/libthr/thread/thr_syscalls.c +++ b/lib/libthr/thread/thr_syscalls.c @@ -169,9 +169,9 @@ __accept(int s, struct sockaddr *addr, socklen_t *addrlen) int ret; curthread = _get_curthread(); - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_accept(s, addr, addrlen); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -187,7 +187,7 @@ __aio_suspend(const struct aiocb * const iocbs[], int niocb, const struct _thr_cancel_enter(curthread); ret = __sys_aio_suspend(iocbs, niocb, timeout); - _thr_cancel_leave(curthread); + _thr_cancel_leave(curthread, 1); return (ret); } @@ -207,9 +207,9 @@ __close(int fd) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 0); + _thr_cancel_enter2(curthread, 0); ret = __sys_close(fd); - _thr_cancel_leave_defer(curthread, 1); + _thr_cancel_leave(curthread, 1); return (ret); } @@ -226,9 +226,9 @@ __connect(int fd, const struct sockaddr *name, socklen_t namelen) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 0); + _thr_cancel_enter(curthread); ret = __sys_connect(fd, name, namelen); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -245,9 +245,9 @@ ___creat(const char *path, mode_t mode) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __creat(path, mode); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -269,30 +269,15 @@ __fcntl(int fd, int cmd,...) va_list ap; va_start(ap, cmd); - switch (cmd) { - case F_DUPFD: - case F_DUP2FD: - ret = __sys_fcntl(fd, cmd, va_arg(ap, int)); - break; - case F_SETFD: - case F_SETFL: - ret = __sys_fcntl(fd, cmd, va_arg(ap, int)); - break; - case F_GETFD: - case F_GETFL: - ret = __sys_fcntl(fd, cmd); - break; - case F_OSETLKW: - case F_SETLKW: - _thr_cancel_enter_defer(curthread, 1); + if (cmd == F_OSETLKW || cmd == F_SETLKW) { + _thr_cancel_enter(curthread); #ifdef SYSCALL_COMPAT ret = __fcntl_compat(fd, cmd, va_arg(ap, void *)); #else ret = __sys_fcntl(fd, cmd, va_arg(ap, void *)); #endif - _thr_cancel_leave_defer(curthread, ret == -1); - break; - default: + _thr_cancel_leave(curthread, ret == -1); + } else { #ifdef SYSCALL_COMPAT ret = __fcntl_compat(fd, cmd, va_arg(ap, void *)); #else @@ -316,9 +301,9 @@ __fsync(int fd) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 0); + _thr_cancel_enter2(curthread, 0); ret = __sys_fsync(fd); - _thr_cancel_leave_defer(curthread, 1); + _thr_cancel_leave(curthread, 1); return (ret); } @@ -335,9 +320,9 @@ __msync(void *addr, size_t len, int flags) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 0); + _thr_cancel_enter2(curthread, 0); ret = __sys_msync(addr, len, flags); - _thr_cancel_leave_defer(curthread, 1); + _thr_cancel_leave(curthread, 1); return ret; } @@ -353,7 +338,7 @@ __nanosleep(const struct timespec *time_to_sleep, _thr_cancel_enter(curthread); ret = __sys_nanosleep(time_to_sleep, time_remaining); - _thr_cancel_leave(curthread); + _thr_cancel_leave(curthread, 1); return (ret); } @@ -380,9 +365,9 @@ __open(const char *path, int flags,...) va_end(ap); } - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_open(path, flags, mode); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -410,9 +395,9 @@ __openat(int fd, const char *path, int flags, ...) va_end(ap); } - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_openat(fd, path, flags, mode); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -430,9 +415,9 @@ __poll(struct pollfd *fds, unsigned int nfds, int timeout) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_poll(fds, nfds, timeout); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -451,9 +436,9 @@ ___pselect(int count, fd_set *rfds, fd_set *wfds, fd_set *efds, struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_pselect(count, rfds, wfds, efds, timo, mask); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -471,9 +456,9 @@ __read(int fd, void *buf, size_t nbytes) struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_read(fd, buf, nbytes); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -491,9 +476,9 @@ __readv(int fd, const struct iovec *iov, int iovcnt) struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_readv(fd, iov, iovcnt); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -511,9 +496,9 @@ __recvfrom(int s, void *b, size_t l, int f, struct sockaddr *from, struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_recvfrom(s, b, l, f, from, fl); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -530,9 +515,9 @@ __recvmsg(int s, struct msghdr *m, int f) struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_recvmsg(s, m, f); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -550,9 +535,9 @@ __select(int numfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_select(numfds, readfds, writefds, exceptfds, timeout); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return ret; } @@ -569,9 +554,9 @@ __sendmsg(int s, const struct msghdr *m, int f) struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_sendmsg(s, m, f); - _thr_cancel_leave_defer(curthread, ret <= 0); + _thr_cancel_leave(curthread, ret <= 0); return (ret); } @@ -589,9 +574,9 @@ __sendto(int s, const void *m, size_t l, int f, const struct sockaddr *t, struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_sendto(s, m, l, f, t, tl); - _thr_cancel_leave_defer(curthread, ret <= 0); + _thr_cancel_leave(curthread, ret <= 0); return (ret); } @@ -605,7 +590,7 @@ ___sleep(unsigned int seconds) _thr_cancel_enter(curthread); ret = __sleep(seconds); - _thr_cancel_leave(curthread); + _thr_cancel_leave(curthread, 1); return (ret); } @@ -620,7 +605,7 @@ ___system(const char *string) _thr_cancel_enter(curthread); ret = __system(string); - _thr_cancel_leave(curthread); + _thr_cancel_leave(curthread, 1); return ret; } @@ -638,9 +623,9 @@ ___tcdrain(int fd) struct pthread *curthread = _get_curthread(); int ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __tcdrain(fd); - _thr_cancel_leave_defer(curthread, ret == -1); + _thr_cancel_leave(curthread, ret == -1); return (ret); } @@ -654,7 +639,7 @@ ___usleep(useconds_t useconds) _thr_cancel_enter(curthread); ret = __usleep(useconds); - _thr_cancel_leave(curthread); + _thr_cancel_leave(curthread, 1); return (ret); } @@ -672,9 +657,9 @@ ___wait(int *istat) struct pthread *curthread = _get_curthread(); pid_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __wait(istat); - _thr_cancel_leave_defer(curthread, ret <= 0); + _thr_cancel_leave(curthread, ret <= 0); return ret; } @@ -692,9 +677,9 @@ __wait3(int *status, int options, struct rusage *rusage) struct pthread *curthread = _get_curthread(); pid_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = _wait4(WAIT_ANY, status, options, rusage); - _thr_cancel_leave_defer(curthread, ret <= 0); + _thr_cancel_leave(curthread, ret <= 0); return (ret); } @@ -712,9 +697,9 @@ __wait4(pid_t pid, int *status, int options, struct rusage *rusage) struct pthread *curthread = _get_curthread(); pid_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_wait4(pid, status, options, rusage); - _thr_cancel_leave_defer(curthread, ret <= 0); + _thr_cancel_leave(curthread, ret <= 0); return ret; } @@ -732,9 +717,9 @@ ___waitpid(pid_t wpid, int *status, int options) struct pthread *curthread = _get_curthread(); pid_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __waitpid(wpid, status, options); - _thr_cancel_leave_defer(curthread, ret <= 0); + _thr_cancel_leave(curthread, ret <= 0); return ret; } @@ -752,9 +737,9 @@ __write(int fd, const void *buf, size_t nbytes) struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_write(fd, buf, nbytes); - _thr_cancel_leave_defer(curthread, (ret <= 0)); + _thr_cancel_leave(curthread, (ret <= 0)); return ret; } @@ -771,8 +756,8 @@ __writev(int fd, const struct iovec *iov, int iovcnt) struct pthread *curthread = _get_curthread(); ssize_t ret; - _thr_cancel_enter_defer(curthread, 1); + _thr_cancel_enter(curthread); ret = __sys_writev(fd, iov, iovcnt); - _thr_cancel_leave_defer(curthread, (ret <= 0)); + _thr_cancel_leave(curthread, (ret <= 0)); return ret; } diff --git a/lib/libthr/thread/thr_umtx.c b/lib/libthr/thread/thr_umtx.c index 5af923dce4f..b712b7af880 100644 --- a/lib/libthr/thread/thr_umtx.c +++ b/lib/libthr/thread/thr_umtx.c @@ -217,3 +217,42 @@ __thr_rwlock_unlock(struct urwlock *rwlock) { return _umtx_op_err(rwlock, UMTX_OP_RW_UNLOCK, 0, NULL, NULL); } + +void +_thr_rwl_rdlock(struct urwlock *rwlock) +{ + int ret; + + for (;;) { + if (_thr_rwlock_tryrdlock(rwlock, URWLOCK_PREFER_READER) == 0) + return; + ret = __thr_rwlock_rdlock(rwlock, URWLOCK_PREFER_READER, NULL); + if (ret == 0) + return; + if (ret != EINTR) + PANIC("rdlock error"); + } +} + +void +_thr_rwl_wrlock(struct urwlock *rwlock) +{ + int ret; + + for (;;) { + if (_thr_rwlock_trywrlock(rwlock) == 0) + return; + ret = __thr_rwlock_wrlock(rwlock, NULL); + if (ret == 0) + return; + if (ret != EINTR) + PANIC("wrlock error"); + } +} + +void +_thr_rwl_unlock(struct urwlock *rwlock) +{ + if (_thr_rwlock_unlock(rwlock)) + PANIC("unlock error"); +} diff --git a/lib/libthr/thread/thr_umtx.h b/lib/libthr/thread/thr_umtx.h index a6e462e29ca..20489849f53 100644 --- a/lib/libthr/thread/thr_umtx.h +++ b/lib/libthr/thread/thr_umtx.h @@ -58,6 +58,11 @@ int __thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp) int __thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp) __hidden; int __thr_rwlock_unlock(struct urwlock *rwlock) __hidden; +/* Internal used only */ +void _thr_rwl_rdlock(struct urwlock *rwlock) __hidden; +void _thr_rwl_wrlock(struct urwlock *rwlock) __hidden; +void _thr_rwl_unlock(struct urwlock *rwlock) __hidden; + static inline int _thr_umutex_trylock(struct umutex *mtx, uint32_t id) { -- 2.45.0