On 07/08/12 05:43, Ian Lance Taylor wrote:
> This patch to libgo, from Shenghou Ma, adds support for NumCPU on
> additional platforms: Solaris, Irix, *BSD, Darwin. Bootstrapped and ran
> Go testsuite on x86_64-unknown-linux-gnu. Committed to mainline.
>
> Ian
>
>
Wouldn't it be more useful on Linux to check the task's affinity
settings? Then when a task is locked to a limited set of cores it won't
overload those cores with threads.
R.
> foo.patch
>
>
> diff -r 12a361bc53d0 libgo/Makefile.am
> --- a/libgo/Makefile.am Mon Aug 06 21:39:47 2012 -0700
> +++ b/libgo/Makefile.am Mon Aug 06 21:40:21 2012 -0700
> @@ -390,6 +390,32 @@
> runtime_lock_files = runtime/lock_sema.c runtime/thread-sema.c
> endif
>
> +if LIBGO_IS_LINUX
> +runtime_getncpu_file = runtime/getncpu-linux.c
> +else
> +if LIBGO_IS_DARWIN
> +runtime_getncpu_file = runtime/getncpu-bsd.c
> +else
> +if LIBGO_IS_IRIX
> +runtime_getncpu_file = runtime/getncpu-irix.c
> +else
> +if LIBGO_IS_SOLARIS
> +runtime_getncpu_file = runtime/getncpu-solaris.c
> +else
> +if LIBGO_IS_FREEBSD
> +runtime_getncpu_file = runtime/getncpu-bsd.c
> +else
> +if LIBGO_IS_NETBSD
> +runtime_getncpu_file = runtime/getncpu-bsd.c
> +else
> +runtime_getncpu_file = runtime/getncpu-none.c
> +endif
> +endif
> +endif
> +endif
> +endif
> +endif
> +
> runtime_files = \
> runtime/go-append.c \
> runtime/go-assert.c \
> @@ -481,7 +507,8 @@
> sema.c \
> sigqueue.c \
> string.c \
> - time.c
> + time.c \
> + $(runtime_getncpu_file)
>
> goc2c.$(OBJEXT): runtime/goc2c.c
> $(CC_FOR_BUILD) -c $(CFLAGS_FOR_BUILD) $<
> diff -r 12a361bc53d0 libgo/runtime/getncpu-bsd.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/libgo/runtime/getncpu-bsd.c Mon Aug 06 21:40:21 2012 -0700
> @@ -0,0 +1,24 @@
> +// Copyright 2012 The Go Authors. All rights reserved.
> +// Use of this source code is governed by a BSD-style
> +// license that can be found in the LICENSE file.
> +
> +#include <sys/types.h>
> +#include <sys/sysctl.h>
> +
> +#include "runtime.h"
> +#include "defs.h"
> +
> +int32
> +getproccount(void)
> +{
> + int mib[2], out;
> + size_t len;
> +
> + mib[0] = CTL_HW;
> + mib[1] = HW_NCPU;
> + len = sizeof(out);
> + if(sysctl(mib, 2, &out, &len, NULL, 0) >= 0)
> + return (int32)out;
> + else
> + return 0;
> +}
> diff -r 12a361bc53d0 libgo/runtime/getncpu-irix.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/libgo/runtime/getncpu-irix.c Mon Aug 06 21:40:21 2012 -0700
> @@ -0,0 +1,16 @@
> +// Copyright 2012 The Go Authors. All rights reserved.
> +// Use of this source code is governed by a BSD-style
> +// license that can be found in the LICENSE file.
> +
> +#include <unistd.h>
> +
> +#include "runtime.h"
> +#include "defs.h"
> +
> +int32
> +getproccount(void)
> +{
> + int32 n;
> + n = (int32)sysconf(_SC_NPROC_ONLN);
> + return n > 1 ? n : 1;
> +}
> diff -r 12a361bc53d0 libgo/runtime/getncpu-linux.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/libgo/runtime/getncpu-linux.c Mon Aug 06 21:40:21 2012 -0700
> @@ -0,0 +1,47 @@
> +// Copyright 2012 The Go Authors. All rights reserved.
> +// Use of this source code is governed by a BSD-style
> +// license that can be found in the LICENSE file.
> +
> +#include <string.h>
> +#include <sys/types.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +
> +#include "runtime.h"
> +#include "defs.h"
> +
> +#ifndef O_CLOEXEC
> +#define O_CLOEXEC 0
> +#endif
> +
> +int32
> +getproccount(void)
> +{
> + int32 fd, rd, cnt, cpustrlen;
> + const char *cpustr;
> + const byte *pos;
> + byte *bufpos;
> + byte buf[256];
> +
> + fd = open("/proc/stat", O_RDONLY|O_CLOEXEC, 0);
> + if(fd == -1)
> + return 1;
> + cnt = 0;
> + bufpos = buf;
> + cpustr = "\ncpu";
> + cpustrlen = strlen(cpustr);
> + for(;;) {
> + rd = read(fd, bufpos, sizeof(buf)-cpustrlen);
> + if(rd == -1)
> + break;
> + bufpos[rd] = 0;
> + for(pos=buf; (pos=(const byte*)strstr((const char*)pos,
> cpustr)) != nil; cnt++, pos++) {
> + }
> + if(rd < cpustrlen)
> + break;
> + memmove(buf, bufpos+rd-cpustrlen+1, cpustrlen-1);
> + bufpos = buf+cpustrlen-1;
> + }
> + close(fd);
> + return cnt ? cnt : 1;
> +}
> diff -r 12a361bc53d0 libgo/runtime/getncpu-none.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/libgo/runtime/getncpu-none.c Mon Aug 06 21:40:21 2012 -0700
> @@ -0,0 +1,12 @@
> +// Copyright 2012 The Go Authors. All rights reserved.
> +// Use of this source code is governed by a BSD-style
> +// license that can be found in the LICENSE file.
> +
> +#include "runtime.h"
> +#include "defs.h"
> +
> +int32
> +getproccount(void)
> +{
> + return 0;
> +}
> diff -r 12a361bc53d0 libgo/runtime/getncpu-solaris.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/libgo/runtime/getncpu-solaris.c Mon Aug 06 21:40:21 2012 -0700
> @@ -0,0 +1,16 @@
> +// Copyright 2012 The Go Authors. All rights reserved.
> +// Use of this source code is governed by a BSD-style
> +// license that can be found in the LICENSE file.
> +
> +#include <unistd.h>
> +
> +#include "runtime.h"
> +#include "defs.h"
> +
> +int32
> +getproccount(void)
> +{
> + int32 n;
> + n = (int32)sysconf(_SC_NPROCESSORS_ONLN);
> + return n > 1 ? n : 1;
> +}
> diff -r 12a361bc53d0 libgo/runtime/runtime.h
> --- a/libgo/runtime/runtime.h Mon Aug 06 21:39:47 2012 -0700
> +++ b/libgo/runtime/runtime.h Mon Aug 06 21:40:21 2012 -0700
> @@ -518,3 +518,5 @@
> extern uintptr runtime_stacks_sys;
>
> extern _Bool __go_file_line (uintptr, String*, String*, int *);
> +
> +int32 getproccount(void);
> diff -r 12a361bc53d0 libgo/runtime/thread-linux.c
> --- a/libgo/runtime/thread-linux.c Mon Aug 06 21:39:47 2012 -0700
> +++ b/libgo/runtime/thread-linux.c Mon Aug 06 21:40:21 2012 -0700
> @@ -72,42 +72,6 @@
> *(int32*)0x1006 = 0x1006;
> }
>
> -#ifndef O_CLOEXEC
> -#define O_CLOEXEC 0
> -#endif
> -
> -static int32
> -getproccount(void)
> -{
> - int32 fd, rd, cnt, cpustrlen;
> - const char *cpustr;
> - const byte *pos;
> - byte *bufpos;
> - byte buf[256];
> -
> - fd = open("/proc/stat", O_RDONLY|O_CLOEXEC, 0);
> - if(fd == -1)
> - return 1;
> - cnt = 0;
> - bufpos = buf;
> - cpustr = "\ncpu";
> - cpustrlen = strlen(cpustr);
> - for(;;) {
> - rd = read(fd, bufpos, sizeof(buf)-cpustrlen);
> - if(rd == -1)
> - break;
> - bufpos[rd] = 0;
> - for(pos=buf; (pos=(const byte*)strstr((const char*)pos,
> cpustr)) != nil; cnt++, pos++) {
> - }
> - if(rd < cpustrlen)
> - break;
> - memmove(buf, bufpos+rd-cpustrlen+1, cpustrlen-1);
> - bufpos = buf+cpustrlen-1;
> - }
> - close(fd);
> - return cnt ? cnt : 1;
> -}
> -
> void
> runtime_osinit(void)
> {
> diff -r 12a361bc53d0 libgo/runtime/thread-sema.c
> --- a/libgo/runtime/thread-sema.c Mon Aug 06 21:39:47 2012 -0700
> +++ b/libgo/runtime/thread-sema.c Mon Aug 06 21:40:21 2012 -0700
> @@ -138,6 +138,7 @@
> void
> runtime_osinit (void)
> {
> + runtime_ncpu = getproccount();
> }
>
> void
>
