diff options
| -rw-r--r-- | libc/sysdeps/linux/common/Makefile | 2 | ||||
| -rw-r--r-- | libc/sysdeps/linux/common/profil.c | 113 |
2 files changed, 114 insertions, 1 deletions
diff --git a/libc/sysdeps/linux/common/Makefile b/libc/sysdeps/linux/common/Makefile index 3135172c0..bee640db9 100644 --- a/libc/sysdeps/linux/common/Makefile +++ b/libc/sysdeps/linux/common/Makefile @@ -26,7 +26,7 @@ CSRC= waitpid.c getdnnm.c gethstnm.c getcwd.c ptrace.c \ truncate64.c getrlimit64.c setrlimit64.c creat64.c \ llseek.c pread_write.c _exit.c sync.c getdirname.c \ sendfile64.c xstatconv.c getdents.c getdents64.c vfork.c \ - ulimit.c + ulimit.c profil.c ifneq ($(strip $(EXCLUDE_BRK)),y) CSRC+=sbrk.c endif diff --git a/libc/sysdeps/linux/common/profil.c b/libc/sysdeps/linux/common/profil.c new file mode 100644 index 000000000..3df0836c1 --- /dev/null +++ b/libc/sysdeps/linux/common/profil.c @@ -0,0 +1,113 @@ +/* Low-level statistical profiling support function. Mostly POSIX.1 version. + Copyright (C) 1996,97,98,2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <sys/types.h> +#include <unistd.h> +#include <errno.h> +#include <signal.h> +#include <sys/time.h> + +#ifndef SIGPROF + +int profil (u_short *sample_buffer, size_t size, size_t offset, u_int scale) +{ + if (scale == 0) + /* Disable profiling. */ + return 0; + __set_errno (ENOSYS); + return -1; +} + +#else + +static u_short *samples; +static size_t nsamples; +static size_t pc_offset; +static u_int pc_scale; + +static inline void +profil_count (void *pc) +{ + size_t i = (pc - pc_offset - (void *) 0) / 2; + if (sizeof (unsigned long long int) > sizeof (size_t)) + i = (unsigned long long int) i * pc_scale / 65536; + else + i = i / 65536 * pc_scale + i % 65536 * pc_scale / 65536; + if (i < nsamples) + ++samples[i]; +} + +/* Get the machine-dependent definition of `profil_counter', the signal + handler for SIGPROF. It calls `profil_count' (above) with the PC of the + interrupted code. */ +#include <bits/profil-counter.h> + + +/* Enable statistical profiling, writing samples of the PC into at most + SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling + is enabled, the system examines the user PC and increments + SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero, + disable profiling. Returns zero on success, -1 on error. */ +int profil (u_short *sample_buffer, size_t size, size_t offset, u_int scale) +{ + static struct sigaction oact; + static struct itimerval otimer; + struct sigaction act; + struct itimerval timer; + + if (sample_buffer == NULL) + { + /* Disable profiling. */ + if (samples == NULL) + /* Wasn't turned on. */ + return 0; + + if (setitimer (ITIMER_PROF, &otimer, NULL) < 0) + return -1; + samples = NULL; + return sigaction (SIGPROF, &oact, NULL); + } + + if (samples) + { + /* Was already turned on. Restore old timer and signal handler + first. */ + if (setitimer (ITIMER_PROF, &otimer, NULL) < 0 + || sigaction (SIGPROF, &oact, NULL) < 0) + return -1; + } + + samples = sample_buffer; + nsamples = size / sizeof *samples; + pc_offset = offset; + pc_scale = scale; + + act.sa_handler = (__sighandler_t) &profil_counter; + act.sa_flags = SA_RESTART; + __sigfillset (&act.sa_mask); + if (sigaction (SIGPROF, &act, &oact) < 0) + return -1; + + timer.it_value.tv_sec = 0; + timer.it_value.tv_usec = 1; + timer.it_interval = timer.it_value; + return setitimer (ITIMER_PROF, &timer, &otimer); +} + +#endif |