diff options
Diffstat (limited to 'libpthread/nptl/sysdeps/unix/sysv/linux/timer_create.c')
| -rw-r--r-- | libpthread/nptl/sysdeps/unix/sysv/linux/timer_create.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/timer_create.c b/libpthread/nptl/sysdeps/unix/sysv/linux/timer_create.c new file mode 100644 index 000000000..9f02fe3b2 --- /dev/null +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/timer_create.c @@ -0,0 +1,236 @@ +/* Copyright (C) 2003,2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2003. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <errno.h> +#include <pthread.h> +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <sysdep.h> +#include <bits/kernel-features.h> +#include <internaltypes.h> +#include <pthreadP.h> +#include "kernel-posix-timers.h" +#include "kernel-posix-cpu-timers.h" + + +#ifdef __NR_timer_create +# ifndef __ASSUME_POSIX_TIMERS +static int compat_timer_create (clockid_t clock_id, struct sigevent *evp, + timer_t *timerid); +# define timer_create static compat_timer_create +# include <nptl/sysdeps/pthread/timer_create.c> +# undef timer_create + +/* Nonzero if the system calls are not available. */ +int __no_posix_timers attribute_hidden; +# endif + +# ifdef timer_create_alias +# define timer_create timer_create_alias +# endif + + +int +timer_create ( + clockid_t clock_id, + struct sigevent *evp, + timer_t *timerid) +{ +# undef timer_create +# ifndef __ASSUME_POSIX_TIMERS + if (__no_posix_timers >= 0) +# endif + { + clockid_t syscall_clockid = (clock_id == CLOCK_PROCESS_CPUTIME_ID + ? MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED) + : clock_id == CLOCK_THREAD_CPUTIME_ID + ? MAKE_THREAD_CPUCLOCK (0, CPUCLOCK_SCHED) + : clock_id); + + /* If the user wants notification via a thread we need to handle + this special. */ + if (evp == NULL + || __builtin_expect (evp->sigev_notify != SIGEV_THREAD, 1)) + { + struct sigevent local_evp; + + /* We avoid allocating too much memory by basically + using struct timer as a derived class with the + first two elements being in the superclass. We only + need these two elements here. */ + struct timer *newp = (struct timer *) malloc (offsetof (struct timer, + thrfunc)); + if (newp == NULL) + /* No more memory. */ + return -1; + + if (evp == NULL) + { + /* The kernel has to pass up the timer ID which is a + userlevel object. Therefore we cannot leave it up to + the kernel to determine it. */ + local_evp.sigev_notify = SIGEV_SIGNAL; + local_evp.sigev_signo = SIGALRM; + local_evp.sigev_value.sival_ptr = newp; + + evp = &local_evp; + } + + kernel_timer_t ktimerid; + int retval = INLINE_SYSCALL (timer_create, 3, syscall_clockid, evp, + &ktimerid); + +# ifndef __ASSUME_POSIX_TIMERS + if (retval != -1 || errno != ENOSYS) +# endif + { +# ifndef __ASSUME_POSIX_TIMERS + __no_posix_timers = 1; +# endif + + if (retval != -1) + { + newp->sigev_notify = (evp != NULL + ? evp->sigev_notify : SIGEV_SIGNAL); + newp->ktimerid = ktimerid; + + *timerid = (timer_t) newp; + } + else + { + /* Cannot allocate the timer, fail. */ + free (newp); + retval = -1; + } + + return retval; + } + + free (newp); + +# ifndef __ASSUME_POSIX_TIMERS + /* When we come here the syscall does not exist. Make sure we + do not try to use it again. */ + __no_posix_timers = -1; +# endif + } + else + { +# ifndef __ASSUME_POSIX_TIMERS + /* Make sure we have the necessary kernel support. */ + if (__no_posix_timers == 0) + { + INTERNAL_SYSCALL_DECL (err); + struct timespec ts; + int res; + res = INTERNAL_SYSCALL (clock_getres, err, 2, + CLOCK_REALTIME, &ts); + __no_posix_timers = (INTERNAL_SYSCALL_ERROR_P (res, err) + ? -1 : 1); + } + + if (__no_posix_timers > 0) +# endif + { + /* Create the helper thread. */ + pthread_once (&__helper_once, __start_helper_thread); + if (__helper_tid == 0) + { + /* No resources to start the helper thread. */ + __set_errno (EAGAIN); + return -1; + } + + struct timer *newp; + newp = (struct timer *) malloc (sizeof (struct timer)); + if (newp == NULL) + return -1; + + /* Copy the thread parameters the user provided. */ + newp->sival = evp->sigev_value; + newp->thrfunc = evp->sigev_notify_function; + + /* We cannot simply copy the thread attributes since the + implementation might keep internal information for + each instance. */ + (void) pthread_attr_init (&newp->attr); + if (evp->sigev_notify_attributes != NULL) + { + struct pthread_attr *nattr; + struct pthread_attr *oattr; + + nattr = (struct pthread_attr *) &newp->attr; + oattr = (struct pthread_attr *) evp->sigev_notify_attributes; + + nattr->schedparam = oattr->schedparam; + nattr->schedpolicy = oattr->schedpolicy; + nattr->flags = oattr->flags; + nattr->guardsize = oattr->guardsize; + nattr->stackaddr = oattr->stackaddr; + nattr->stacksize = oattr->stacksize; + } + + /* In any case set the detach flag. */ + (void) pthread_attr_setdetachstate (&newp->attr, + PTHREAD_CREATE_DETACHED); + + /* Create the event structure for the kernel timer. */ + struct sigevent sev; + sev.sigev_value.sival_ptr = newp; + sev.sigev_signo = SIGTIMER; + sev.sigev_notify = SIGEV_SIGNAL | SIGEV_THREAD_ID; + /* This is the thread ID of the helper thread. */ + sev._sigev_un._pad[0] = __helper_tid; + + /* Create the timer. */ + INTERNAL_SYSCALL_DECL (err); + int res; + res = INTERNAL_SYSCALL (timer_create, err, 3, + syscall_clockid, &sev, &newp->ktimerid); + if (! INTERNAL_SYSCALL_ERROR_P (res, err)) + { + *timerid = (timer_t) newp; + return 0; + } + + /* Free the resources. */ + free (newp); + + __set_errno (INTERNAL_SYSCALL_ERRNO (res, err)); + + return -1; + } + } + } + +# ifndef __ASSUME_POSIX_TIMERS + /* Compatibility code. */ + return compat_timer_create (clock_id, evp, timerid); +# endif +} +#else +# ifdef timer_create_alias +# define timer_create timer_create_alias +# endif +/* The new system calls are not available. Use the userlevel + implementation. */ +# include <nptl/sysdeps/pthread/timer_create.c> +#endif |