From 7006f757e6d6f110b88f6a5a7759d1e118870489 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Tue, 1 Nov 2005 02:13:41 +0000 Subject: * sysdeps/powerpc/powerpc64/Makefile (sysdep_routines, elide-routines.os): Add hp-timing. * sysdeps/powerpc/powerpc64/hp-timing.c: New file. * sysdeps/powerpc/powerpc64/hp-timing.h: New file. * sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c: New file. --- sysdeps/powerpc/powerpc64/Makefile | 2 + sysdeps/powerpc/powerpc64/hp-timing.c | 25 +++++ sysdeps/powerpc/powerpc64/hp-timing.h | 136 ++++++++++++++++++++++++ sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c | 105 ++++++++++++++++++ 4 files changed, 268 insertions(+) create mode 100644 sysdeps/powerpc/powerpc64/hp-timing.c create mode 100644 sysdeps/powerpc/powerpc64/hp-timing.h create mode 100644 sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c (limited to 'sysdeps') diff --git a/sysdeps/powerpc/powerpc64/Makefile b/sysdeps/powerpc/powerpc64/Makefile index cf29148ff3..cf7c4337e0 100644 --- a/sysdeps/powerpc/powerpc64/Makefile +++ b/sysdeps/powerpc/powerpc64/Makefile @@ -11,6 +11,8 @@ pic-ccflag = -fpic endif ifeq ($(subdir),csu) +sysdep_routines += hp-timing +elide-routines.os += hp-timing ifneq ($(elf),no) # The initfini generation code doesn't work in the presence of -fPIC, so # we use -fpic instead which is much better. diff --git a/sysdeps/powerpc/powerpc64/hp-timing.c b/sysdeps/powerpc/powerpc64/hp-timing.c new file mode 100644 index 0000000000..4e54e66e5e --- /dev/null +++ b/sysdeps/powerpc/powerpc64/hp-timing.c @@ -0,0 +1,25 @@ +/* Support for high precision, low overhead timing functions. + powerpc64 version. + Copyright (C) 2005 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 1998. + + 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 + +/* We have to define the variable for the overhead. */ +hp_timing_t _dl_hp_timing_overhead; diff --git a/sysdeps/powerpc/powerpc64/hp-timing.h b/sysdeps/powerpc/powerpc64/hp-timing.h new file mode 100644 index 0000000000..b58cca9003 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/hp-timing.h @@ -0,0 +1,136 @@ +/* High precision, low overhead timing functions. powerpc64 version. + Copyright (C) 2005 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 1998. + + 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. */ + +#ifndef _HP_TIMING_H +#define _HP_TIMING_H 1 + +#include +#include +#include +#include + +/* The macros defined here use the powerpc 64-bit time base register. + The time base is nominally clocked at 1/8th the CPU clock, but this + can vary. + + The list of macros we need includes the following: + + - HP_TIMING_AVAIL: test for availability. + + - HP_TIMING_INLINE: this macro is non-zero if the functionality is not + implemented using function calls but instead uses some inlined code + which might simply consist of a few assembler instructions. We have to + know this since we might want to use the macros here in places where we + cannot make function calls. + + - hp_timing_t: This is the type for variables used to store the time + values. + + - HP_TIMING_ZERO: clear `hp_timing_t' object. + + - HP_TIMING_NOW: place timestamp for current time in variable given as + parameter. + + - HP_TIMING_DIFF_INIT: do whatever is necessary to be able to use the + HP_TIMING_DIFF macro. + + - HP_TIMING_DIFF: compute difference between two times and store it + in a third. Source and destination might overlap. + + - HP_TIMING_ACCUM: add time difference to another variable. This might + be a bit more complicated to implement for some platforms as the + operation should be thread-safe and 64bit arithmetic on 32bit platforms + is not. + + - HP_TIMING_ACCUM_NT: this is the variant for situations where we know + there are no threads involved. + + - HP_TIMING_PRINT: write decimal representation of the timing value into + the given string. This operation need not be inline even though + HP_TIMING_INLINE is specified. + +*/ + +/* We always assume having the timestamp register. */ +#define HP_TIMING_AVAIL (1) + +/* We indeed have inlined functions. */ +#define HP_TIMING_INLINE (1) + +/* We use 64bit values for the times. */ +typedef unsigned long long int hp_timing_t; + +/* Set timestamp value to zero. */ +#define HP_TIMING_ZERO(Var) (Var) = (0) + +/* That's quite simple. Use the `mftb' instruction. Note that the value + might not be 100% accurate since there might be some more instructions + running in this moment. This could be changed by using a barrier like + 'lwsync' right before the `mftb' instruciton. But we are not interested + in accurate clock cycles here so we don't do this. */ +#define HP_TIMING_NOW(Var) __asm__ __volatile__ ("mftb %0" : "=r" (Var)) + +/* Use two 'mftb' instructions in a row to find out how long it takes. + On current POWER4, POWER5, and 970 processors mftb take ~10 cycles. */ +#define HP_TIMING_DIFF_INIT() \ + do { \ + if (GLRO(dl_hp_timing_overhead) == 0) \ + { \ + int __cnt = 5; \ + GLRO(dl_hp_timing_overhead) = ~0ull; \ + do \ + { \ + hp_timing_t __t1, __t2; \ + HP_TIMING_NOW (__t1); \ + HP_TIMING_NOW (__t2); \ + if (__t2 - __t1 < GLRO(dl_hp_timing_overhead)) \ + GLRO(dl_hp_timing_overhead) = __t2 - __t1; \ + } \ + while (--__cnt > 0); \ + } \ + } while (0) + +/* It's simple arithmetic in 64-bit. */ +#define HP_TIMING_DIFF(Diff, Start, End) (Diff) = ((End) - (Start)) + +/* We need to insure that this add is atomic in threaded environments. We use + __arch_atomic_exchange_and_add_64 from atomic.h to get thread safety. */ +#define HP_TIMING_ACCUM(Sum, Diff) \ + do { \ + hp_timing_t __diff = (Diff) - GLRO(dl_hp_timing_overhead); \ + __arch_atomic_exchange_and_add_64 (&(Sum), __diff); \ + } while (0) + +/* No threads, no extra work. */ +#define HP_TIMING_ACCUM_NT(Sum, Diff) (Sum) += (Diff) + +/* Print the time value. */ +#define HP_TIMING_PRINT(Buf, Len, Val) \ + do { \ + char __buf[20]; \ + char *__cp = _itoa (Val, __buf + sizeof (__buf), 10, 0); \ + size_t __len = (Len); \ + char *__dest = (Buf); \ + while (__len-- > 0 && __cp < __buf + sizeof (__buf)) \ + *__dest++ = *__cp++; \ + memcpy (__dest, " ticks", MIN (__len, sizeof (" ticks"))); \ + } while (0) + +#endif /* hp-timing.h */ diff --git a/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c b/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c new file mode 100644 index 0000000000..ddaff303c5 --- /dev/null +++ b/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c @@ -0,0 +1,105 @@ +/* Get frequency of the system processor. powerpc/Linux version. + Copyright (C) 2000, 2001, 2005 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 +#include +#include +#include +#include + + +hp_timing_t +__get_clockfreq (void) +{ + /* We read the information from the /proc filesystem. /proc/cpuinfo + contains at least one line like: + timebase : 33333333 + We search for this line and convert the number into an integer. */ + static hp_timing_t timebase_freq; + hp_timing_t result = 0L; + + /* If this function was called before, we know the result. */ + if (timebase_freq != 0) + return timebase_freq; + + int fd = open ("/proc/cpuinfo", O_RDONLY); + if (__builtin_expect (fd != -1, 1)) + { + /* The timebase will be in the 1st 1024 bytes for systems with up + to 8 processors. If the first read returns less then 1024 + bytes read, we have the whole cpuinfo and can start the scan. + Otherwise we will have to read more to insure we have the + timebase value in the scan. */ + char buf[1024]; + ssize_t n; + + n = read (fd, buf, sizeof (buf)); + if (n == sizeof (buf)) + { + /* We are here because the 1st read returned exactly sizeof + (buf) bytes. This implies that we are not at EOF and may + not have read the timebase value yet. So we need to read + more bytes until we know we have EOF. We copy the lower + half of buf to the upper half and read sizeof (buf)/2 + bytes into the lower half of buf and repeat until we + reach EOF. We can assume that the timebase will be in + the last 512 bytes of cpuinfo, so two 512 byte half_bufs + will be sufficient to contain the timebase and will + handle the case where the timebase spans the half_buf + boundry. */ + const ssize_t half_buf = sizeof (buf) / 2; + while (n >= half_buf) + { + memcpy (buf, buf + half_buf, half_buf); + n = read (fd, buf + half_buf, half_buf); + } + if (n >= 0) + n += half_buf; + } + + if (__builtin_expect (n, 1) > 0) + { + char *mhz = memmem (buf, n, "timebase", 7); + + if (__builtin_expect (mhz != NULL, 1)) + { + char *endp = buf + n; + + /* Search for the beginning of the string. */ + while (mhz < endp && (*mhz < '0' || *mhz > '9') && *mhz != '\n') + ++mhz; + + while (mhz < endp && *mhz != '\n') + { + if (*mhz >= '0' && *mhz <= '9') + { + result *= 10; + result += *mhz - '0'; + } + + ++mhz; + } + } + timebase_freq = result; + } + close (fd); + } + + return timebase_freq; +} -- cgit v1.2.3