diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | posix/sched_cpucount.c | 14 | ||||
| -rw-r--r-- | sysdeps/x86_64/sched_cpucount.c | 26 |
3 files changed, 41 insertions, 5 deletions
@@ -1,3 +1,9 @@ +2007-06-08 Ulrich Drepper <drepper@redhat.com> + + * posix/sched_cpucount.c (__sched_cpucount): Allow using special + instruction for counting bits. + * sysdeps/x86_64/sched_cpucount.c: New file. + 2007-06-07 Ulrich Drepper <drepper@redhat.com> * configure.in: Avoid variable named BASH. diff --git a/posix/sched_cpucount.c b/posix/sched_cpucount.c index fd2687d8af..331c0b8dfc 100644 --- a/posix/sched_cpucount.c +++ b/posix/sched_cpucount.c @@ -21,18 +21,22 @@ int -__sched_cpucount (size_t setsize, cpu_set_t *setp) +__sched_cpucount (size_t setsize, const cpu_set_t *setp) { int s = 0; - for (unsigned int j = 0; j < setsize / sizeof (__cpu_mask); ++j) + const __cpu_mask *p = setp->__bits; + const __cpu_mask *end = &setp->__bits[setsize / sizeof (__cpu_mask)]; + + while (p < end) { - __cpu_mask l = setp->__bits[j]; - if (l == 0) - continue; + __cpu_mask l = *p++; #ifdef POPCNT s += POPCNT (l); #else + if (l == 0) + continue; + # if LONG_BIT > 32 l = (l & 0x5555555555555555ul) + ((l >> 1) & 0x5555555555555555ul); l = (l & 0x3333333333333333ul) + ((l >> 2) & 0x3333333333333333ul); diff --git a/sysdeps/x86_64/sched_cpucount.c b/sysdeps/x86_64/sched_cpucount.c new file mode 100644 index 0000000000..63d84a62e8 --- /dev/null +++ b/sysdeps/x86_64/sched_cpucount.c @@ -0,0 +1,26 @@ +/* Copyright (C) 2007 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. */ + +#ifdef __amdfam10 +# define POPCNT(l) \ + ({ __cpu_mask r; \ + asm ("popcntq %1, %0" : "=r" (r) : "0" (l)); \ + r; }) +#endif + +#include <posix/sched_cpucount.c> |