From 74604ed9c419ab380cacaaeb78e4c26f9f37e0ad Mon Sep 17 00:00:00 2001 From: davidxu Date: Sat, 25 Sep 2010 01:57:47 +0000 Subject: To support stack unwinding for cancellation points, add -fexceptions flag for them, two functions _pthread_cancel_enter and _pthread_cancel_leave are added to let thread enter and leave a cancellation point, it also makes it possible that other functions can be cancellation points in libraries without having to be rewritten in libthr. --- lib/libc/Makefile | 7 +++++++ lib/libc/gen/Makefile.inc | 10 +++++++++- lib/libc/gen/Symbol.map | 2 ++ lib/libc/gen/_pthread_stubs.c | 4 ++++ lib/libc/gen/sem.c | 31 +++++++++---------------------- lib/libc/gen/sem_new.c | 37 +++++++------------------------------ lib/libc/include/libc_private.h | 5 +++++ lib/librt/Makefile | 5 +++-- lib/librt/mq.c | 21 +++++++++------------ lib/libthr/Makefile | 4 +--- lib/libthr/pthread.map | 2 ++ lib/libthr/thread/thr_cancel.c | 12 ++++++++++++ lib/libthr/thread/thr_init.c | 4 +++- lib/libthr/thread/thr_private.h | 3 ++- 14 files changed, 75 insertions(+), 72 deletions(-) (limited to 'lib') diff --git a/lib/libc/Makefile b/lib/libc/Makefile index dae4db3..3cff71f 100644 --- a/lib/libc/Makefile +++ b/lib/libc/Makefile @@ -31,6 +31,11 @@ CLEANFILES+=tags INSTALL_PIC_ARCHIVE= PRECIOUSLIB= +.ifndef NO_THREAD_STACK_UNWIND +CANCELPOINTS_CFLAGS=-fexceptions +CFLAGS+=${CANCELPOINTS_CFLAGS} +.endif + # # Only link with static libgcc.a (no libgcc_eh.a). # @@ -145,3 +150,5 @@ CWARNFLAGS:= ${.IMPSRC:Ngdtoa_*.c:C/^.+$/${CWARNFLAGS}/:C/^$/-w/} SSP_CFLAGS:= ${SSP_CFLAGS:S/^-fstack-protector-all$/-fstack-protector/} # Disable stack protection for SSP symbols. SSP_CFLAGS:= ${.IMPSRC:N*/stack_protector.c:C/^.+$/${SSP_CFLAGS}/} +# Generate stack unwinding tables for cancellation points +CANCELPOINTS_CFLAGS:= ${.IMPSRC:Mcancelpoints_*:C/^.+$/${CANCELPOINTS_CFLAGS}/:C/^$//} diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc index dd4bb5a..32888dd 100644 --- a/lib/libc/gen/Makefile.inc +++ b/lib/libc/gen/Makefile.inc @@ -25,7 +25,7 @@ SRCS+= __getosreldate.c __xuname.c \ pause.c pmadvise.c popen.c posix_spawn.c \ psignal.c pututxline.c pw_scan.c pwcache.c \ raise.c readdir.c readpassphrase.c rewinddir.c \ - scandir.c seed48.c seekdir.c sem.c sem_new.c semctl.c \ + scandir.c seed48.c seekdir.c semctl.c \ setdomainname.c sethostname.c setjmperr.c setmode.c \ setproctitle.c setprogname.c siginterrupt.c siglist.c signal.c \ sigsetops.c sleep.c srand48.c statvfs.c stringlist.c strtofflags.c \ @@ -35,6 +35,14 @@ SRCS+= __getosreldate.c __xuname.c \ usleep.c utime.c utxdb.c valloc.c vis.c wait.c wait3.c waitpid.c \ wordexp.c +CANCELPOINTS_SRCS=sem.c sem_new.c +.for src in ${CANCELPOINTS_SRCS} +SRCS+=cancelpoints_${src} +CLEANFILES+=cancelpoints_${src} +cancelpoints_${src}: + ln -sf ${.CURDIR}/gen/${src} ${.TARGET} +.endfor + SYM_MAPS+=${.CURDIR}/gen/Symbol.map # machine-dependent gen sources diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map index 6bd3140..dd375b0 100644 --- a/lib/libc/gen/Symbol.map +++ b/lib/libc/gen/Symbol.map @@ -403,6 +403,8 @@ FBSDprivate_1.0 { _pthread_attr_setstackaddr; _pthread_attr_setstacksize; _pthread_cancel; + _pthread_cancel_enter; + _pthread_cancel_leave; _pthread_cleanup_pop; _pthread_cleanup_push; _pthread_cond_broadcast; diff --git a/lib/libc/gen/_pthread_stubs.c b/lib/libc/gen/_pthread_stubs.c index 044e299e..355b904 100644 --- a/lib/libc/gen/_pthread_stubs.c +++ b/lib/libc/gen/_pthread_stubs.c @@ -121,6 +121,8 @@ pthread_func_entry_t __thr_jtable[PJT_MAX] = { {PJT_DUAL_ENTRY(stub_zero)}, /* PJT_TESTCANCEL */ {PJT_DUAL_ENTRY(stub_zero)}, /* PJT_CLEANUP_POP_IMP */ {PJT_DUAL_ENTRY(stub_zero)}, /* PJT_CLEANUP_PUSH_IMP */ + {PJT_DUAL_ENTRY(stub_zero)}, /* PJT_CANCEL_ENTER */ + {PJT_DUAL_ENTRY(stub_zero)}, /* PJT_CANCEL_LEAVE */ }; /* @@ -269,6 +271,8 @@ STUB_FUNC2(pthread_setcanceltype, PJT_SETCANCELTYPE, int, int, void *) STUB_FUNC(pthread_testcancel, PJT_TESTCANCEL, void) STUB_FUNC1(__pthread_cleanup_pop_imp, PJT_CLEANUP_POP_IMP, int, int) STUB_FUNC2(__pthread_cleanup_push_imp, PJT_CLEANUP_PUSH_IMP, void, void*, void *); +STUB_FUNC1(_pthread_cancel_enter, PJT_CANCEL_ENTER, int, int) +STUB_FUNC1(_pthread_cancel_leave, PJT_CANCEL_LEAVE, int, int) static int stub_zero(void) diff --git a/lib/libc/gen/sem.c b/lib/libc/gen/sem.c index 628e650..e9ae669 100644 --- a/lib/libc/gen/sem.c +++ b/lib/libc/gen/sem.c @@ -312,21 +312,6 @@ _libc_sem_unlink_compat(const char *name) } static int -enable_async_cancel(void) -{ - int old; - - _pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old); - return (old); -} - -static void -restore_async_cancel(int val) -{ - _pthread_setcanceltype(val, NULL); -} - -static int _umtx_wait_uint(volatile unsigned *mtx, unsigned id, const struct timespec *timeout) { if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 && @@ -371,15 +356,15 @@ _libc_sem_timedwait_compat(sem_t * __restrict sem, const struct timespec * __restrict abstime) { struct timespec ts, ts2; - int val, retval, saved_cancel; + int val, retval; if (sem_check_validity(sem) != 0) return (-1); if ((*sem)->syssem != 0) { - saved_cancel = enable_async_cancel(); - retval = ksem_wait((*sem)->semid); - restore_async_cancel(saved_cancel); + _pthread_cancel_enter(1); + retval = ksem_wait((*sem)->semid); /* XXX no timeout */ + _pthread_cancel_leave(retval == -1); return (retval); } @@ -390,8 +375,10 @@ _libc_sem_timedwait_compat(sem_t * __restrict sem, if (atomic_cmpset_acq_int(&(*sem)->count, val, val - 1)) return (0); } - if (retval) + if (retval) { + _pthread_testcancel(); break; + } if (abstime) { if (abstime->tv_nsec >= 1000000000 || abstime->tv_nsec < 0) { errno = EINVAL; @@ -402,9 +389,9 @@ _libc_sem_timedwait_compat(sem_t * __restrict sem, } atomic_add_int(&(*sem)->nwaiters, 1); pthread_cleanup_push(sem_cancel_handler, sem); - saved_cancel = enable_async_cancel(); + _pthread_cancel_enter(1); retval = _umtx_wait_uint(&(*sem)->count, 0, abstime ? &ts2 : NULL); - restore_async_cancel(saved_cancel); + _pthread_cancel_leave(0); pthread_cleanup_pop(0); atomic_add_int(&(*sem)->nwaiters, -1); } diff --git a/lib/libc/gen/sem_new.c b/lib/libc/gen/sem_new.c index ef4ba68..2698b40 100644 --- a/lib/libc/gen/sem_new.c +++ b/lib/libc/gen/sem_new.c @@ -47,6 +47,7 @@ #include #include #include "un-namespace.h" +#include "libc_private.h" __weak_reference(_sem_close, sem_close); __weak_reference(_sem_destroy, sem_destroy); @@ -364,15 +365,6 @@ _sem_trywait(sem_t *sem) return (-1); } -static void -sem_cancel_handler(void *arg) -{ - sem_t *sem = arg; - - if (sem->_kern._has_waiters && sem->_kern._count) - usem_wake(&sem->_kern); -} - #define TIMESPEC_SUB(dst, src, val) \ do { \ (dst)->tv_sec = (src)->tv_sec - (val)->tv_sec; \ @@ -384,27 +376,12 @@ sem_cancel_handler(void *arg) } while (0) -static __inline int -enable_async_cancel(void) -{ - int old; - - _pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old); - return (old); -} - -static __inline void -restore_async_cancel(int val) -{ - _pthread_setcanceltype(val, NULL); -} - int _sem_timedwait(sem_t * __restrict sem, const struct timespec * __restrict abstime) { struct timespec ts, ts2; - int val, retval, saved_cancel; + int val, retval; if (sem_check_validity(sem) != 0) return (-1); @@ -416,8 +393,10 @@ _sem_timedwait(sem_t * __restrict sem, return (0); } - if (retval) + if (retval) { + _pthread_testcancel(); break; + } /* * The timeout argument is only supposed to @@ -431,11 +410,9 @@ _sem_timedwait(sem_t * __restrict sem, clock_gettime(CLOCK_REALTIME, &ts); TIMESPEC_SUB(&ts2, abstime, &ts); } - pthread_cleanup_push(sem_cancel_handler, sem); - saved_cancel = enable_async_cancel(); + _pthread_cancel_enter(1); retval = usem_wait(&sem->_kern, abstime ? &ts2 : NULL); - restore_async_cancel(saved_cancel); - pthread_cleanup_pop(0); + _pthread_cancel_leave(0); } return (retval); } diff --git a/lib/libc/include/libc_private.h b/lib/libc/include/libc_private.h index c5f6eb3..a4737fe 100644 --- a/lib/libc/include/libc_private.h +++ b/lib/libc/include/libc_private.h @@ -129,6 +129,8 @@ typedef enum { PJT_TESTCANCEL, PJT_CLEANUP_POP_IMP, PJT_CLEANUP_PUSH_IMP, + PJT_CANCEL_ENTER, + PJT_CANCEL_LEAVE, PJT_MAX } pjt_index_t; @@ -217,4 +219,7 @@ int _elf_aux_info(int aux, void *buf, int buflen); struct dl_phdr_info; int __elf_phdr_match_addr(struct dl_phdr_info *, void *); +void _pthread_cancel_enter(int); +void _pthread_cancel_leave(int); + #endif /* _LIBC_PRIVATE_H_ */ diff --git a/lib/librt/Makefile b/lib/librt/Makefile index f98d94e..86be751 100644 --- a/lib/librt/Makefile +++ b/lib/librt/Makefile @@ -3,14 +3,15 @@ LIB=rt SHLIB_MAJOR= 1 CFLAGS+=-I${.CURDIR}/../libc/include -I${.CURDIR} +.ifndef NO_THREAD_STACK_UNWIND +CFLAGS+=-fexceptions +.endif CFLAGS+=-Winline -Wall -g DPADD= ${LIBPTHREAD} LDADD= -lpthread WARNS?= 2 -#MAN= libthr.3 - SRCS+= aio.c mq.c sigev_thread.c timer.c PRECIOUSLIB= diff --git a/lib/librt/mq.c b/lib/librt/mq.c index f2e01ca..750e969 100644 --- a/lib/librt/mq.c +++ b/lib/librt/mq.c @@ -39,6 +39,7 @@ #include #include "sigev_thread.h" #include "un-namespace.h" +#include "libc_private.h" extern int __sys_kmq_notify(int, const struct sigevent *); extern int __sys_kmq_open(const char *, int, mode_t, @@ -200,12 +201,11 @@ ssize_t __mq_timedreceive_cancel(mqd_t mqd, char *buf, size_t len, unsigned *prio, const struct timespec *timeout) { - int oldtype; int ret; - _pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype); + _pthread_cancel_enter(1); ret = __sys_kmq_timedreceive(mqd->oshandle, buf, len, prio, timeout); - _pthread_setcanceltype(oldtype, NULL); + _pthread_cancel_leave(ret == -1); return (ret); } @@ -219,12 +219,11 @@ __mq_receive(mqd_t mqd, char *buf, size_t len, unsigned *prio) ssize_t __mq_receive_cancel(mqd_t mqd, char *buf, size_t len, unsigned *prio) { - int oldtype; int ret; - _pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype); + _pthread_cancel_enter(1); ret = __sys_kmq_timedreceive(mqd->oshandle, buf, len, prio, NULL); - _pthread_setcanceltype(oldtype, NULL); + _pthread_cancel_leave(ret == -1); return (ret); } ssize_t @@ -239,12 +238,11 @@ ssize_t __mq_timedsend_cancel(mqd_t mqd, char *buf, size_t len, unsigned prio, const struct timespec *timeout) { - int oldtype; int ret; - _pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype); + _pthread_cancel_enter(1); ret = __sys_kmq_timedsend(mqd->oshandle, buf, len, prio, timeout); - _pthread_setcanceltype(oldtype, NULL); + _pthread_cancel_leave(ret == -1); return (ret); } @@ -259,12 +257,11 @@ __mq_send(mqd_t mqd, char *buf, size_t len, unsigned prio) ssize_t __mq_send_cancel(mqd_t mqd, char *buf, size_t len, unsigned prio) { - int oldtype; int ret; - _pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype); + _pthread_cancel_enter(1); ret = __sys_kmq_timedsend(mqd->oshandle, buf, len, prio, NULL); - _pthread_setcanceltype(oldtype, NULL); + _pthread_cancel_leave(ret == -1); return (ret); } diff --git a/lib/libthr/Makefile b/lib/libthr/Makefile index 8b7af3a..a51b446 100644 --- a/lib/libthr/Makefile +++ b/lib/libthr/Makefile @@ -26,9 +26,7 @@ CFLAGS+=-I${.CURDIR}/../../libexec/rtld-elf/${MACHINE_CPUARCH} CFLAGS+=-I${.CURDIR}/../libthread_db CFLAGS+=-Winline -LIBTHR_UNWIND_STACK=yes - -.ifdef LIBTHR_UNWIND_STACK +.ifndef NO_THREAD_UNWIND_STACK CFLAGS+=-I${.CURDIR}/../../contrib/gcc -fexceptions CFLAGS+=-D_PTHREAD_FORCED_UNWIND .endif diff --git a/lib/libthr/pthread.map b/lib/libthr/pthread.map index bcb5c08..5e36239 100644 --- a/lib/libthr/pthread.map +++ b/lib/libthr/pthread.map @@ -246,6 +246,8 @@ FBSDprivate_1.0 { _pthread_attr_setstackaddr; _pthread_attr_setstacksize; _pthread_cancel; + _pthread_cancel_enter; + _pthread_cancel_leave; _pthread_cleanup_pop; _pthread_cleanup_push; _pthread_cond_broadcast; diff --git a/lib/libthr/thread/thr_cancel.c b/lib/libthr/thread/thr_cancel.c index cd456b7..89f0ee1 100644 --- a/lib/libthr/thread/thr_cancel.c +++ b/lib/libthr/thread/thr_cancel.c @@ -162,3 +162,15 @@ _thr_cancel_leave(struct pthread *curthread, int maycancel) !THR_IN_CRITICAL(curthread) && maycancel)) _pthread_exit(PTHREAD_CANCELED); } + +void +_pthread_cancel_enter(int maycancel) +{ + _thr_cancel_enter2(_get_curthread(), maycancel); +} + +void +_pthread_cancel_leave(int maycancel) +{ + _thr_cancel_leave(_get_curthread(), maycancel); +} diff --git a/lib/libthr/thread/thr_init.c b/lib/libthr/thread/thr_init.c index 56541a8..e8a01d3 100644 --- a/lib/libthr/thread/thr_init.c +++ b/lib/libthr/thread/thr_init.c @@ -248,7 +248,9 @@ static pthread_func_t jmp_table[][2] = { {DUAL_ENTRY(_pthread_sigmask)}, /* PJT_SIGMASK */ {DUAL_ENTRY(_pthread_testcancel)}, /* PJT_TESTCANCEL */ {DUAL_ENTRY(__pthread_cleanup_pop_imp)},/* PJT_CLEANUP_POP_IMP */ - {DUAL_ENTRY(__pthread_cleanup_push_imp)}/* PJT_CLEANUP_PUSH_IMP */ + {DUAL_ENTRY(__pthread_cleanup_push_imp)},/* PJT_CLEANUP_PUSH_IMP */ + {DUAL_ENTRY(_pthread_cancel_enter)}, /* PJT_CANCEL_ENTER */ + {DUAL_ENTRY(_pthread_cancel_leave)} /* PJT_CANCEL_LEAVE */ }; static int init_once = 0; diff --git a/lib/libthr/thread/thr_private.h b/lib/libthr/thread/thr_private.h index a42b4ec..e5a82b9 100644 --- a/lib/libthr/thread/thr_private.h +++ b/lib/libthr/thread/thr_private.h @@ -716,7 +716,8 @@ 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; - +void _pthread_cancel_enter(int maycancel); +void _pthread_cancel_leave(int maycancel); /* #include */ #ifdef _SYS_FCNTL_H_ -- cgit v1.1