From: Russ Cox Date: Tue, 28 Feb 2012 21:18:24 +0000 (-0500) Subject: runtime/pprof: support OS X CPU profiling X-Git-Tag: weekly.2012-03-04~105 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=6e2ae0a12c0f73da56d4f465e68208731b4b16be;p=gostls13.git runtime/pprof: support OS X CPU profiling Work around profiling kernel bug with signal masks. Still broken on 64-bit Snow Leopard kernel, but I think we can ignore that one and let people upgrade to Lion. Add new trivial tools addr2line and objdump to take the place of the GNU tools of the same name, since those are not installed on OS X. Adapt pprof to invoke 'go tool addr2line' and 'go tool objdump' if the system tools do not exist. Clean up disassembly of base register on amd64. Fixes #2008. R=golang-dev, bradfitz, mikioh.mikioh, r, iant CC=golang-dev https://golang.org/cl/5697066 --- diff --git a/misc/pprof b/misc/pprof index 777a45cb7c..2fe56503c9 100755 --- a/misc/pprof +++ b/misc/pprof @@ -1,7 +1,7 @@ #! /usr/bin/env perl # This is a copy of http://google-perftools.googlecode.com/svn/trunk/src/pprof -# with local modifications to handle generation of SVG images and +# with local modifications to handle generation of SVG images and # the Go-style pprof paths. These modifications will probably filter # back into the official source before long. # It's convenient to have a copy here because we need just the one @@ -9,11 +9,11 @@ # Copyright (c) 1998-2007, Google Inc. # All rights reserved. -# +# # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: -# +# # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above @@ -23,7 +23,7 @@ # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. -# +# # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR @@ -1234,6 +1234,13 @@ sub Disassemble { my $cmd = sprintf("$objdump -C -d -l --no-show-raw-insn " . "--start-address=0x$start_addr " . "--stop-address=0x$end_addr $prog"); + + if (system("$objdump --help >/dev/null 2>&1") != 0) { + # objdump must not exist. Fall back to go tool objdump. + $objdump = "go tool objdump"; + $cmd = "$objdump $prog 0x$start_addr 0x$end_addr"; + } + open(OBJDUMP, "$cmd |") || error("$objdump: $!\n"); my @result = (); my $filename = ""; @@ -1305,10 +1312,10 @@ sub PrintListing { my $cumulative = shift; my $list_opts = shift; my $html = shift; - + my $output = \*STDOUT; my $fname = ""; - + if ($html) { # Arrange to write the output to a temporary file @@ -1323,7 +1330,7 @@ sub PrintListing { printf $output ("
%s
Total: %s %s
\n", $main::prog, Unparse($total), Units()); } - + my $listed = 0; foreach my $lib (@{$libs}) { my $symbol_table = GetProcedureBoundaries($lib->[0], $list_opts); @@ -2221,7 +2228,7 @@ function handleMouseWheel(evt) { z = 0.1; if(z > 10.0) z = 10.0; - + var g = svgDoc.getElementById("viewport"); var p = getEventPoint(evt); @@ -4391,6 +4398,12 @@ sub MapToSymbols { $cmd = "$addr2line --demangle -f -C -e $image"; } + if (system("$addr2line --help >/dev/null 2>&1") != 0) { + # addr2line must not exist. Fall back to go tool addr2line. + $addr2line = "go tool addr2line"; + $cmd = "$addr2line $image"; + } + # If "addr2line" isn't installed on the system at all, just use # nm to get what info we can (function names, but not line numbers). if (system("$addr2line --help >/dev/null 2>&1") != 0) { @@ -4434,7 +4447,7 @@ sub MapToSymbols { if ($debug) { print("----\n"); system("cat $main::tmpfile_sym"); - print("----\n"); + print("---- $cmd\n"); system("$cmd <$main::tmpfile_sym"); print("----\n"); } @@ -4544,7 +4557,7 @@ sub ShortFunctionName { # Trim overly long symbols found in disassembler output sub CleanDisassembly { my $d = shift; - while ($d =~ s/(?]*>/$1/g) { } # Remove template arguments return $d; } @@ -4625,7 +4638,7 @@ sub ConfigureTool { my $dirname = $`; # this is everything up to and including the last slash if (-x "$dirname$tool") { $path = "$dirname$tool"; - } else { + } else { $path = $tool; } } diff --git a/src/cmd/addr2line/main.c b/src/cmd/addr2line/main.c new file mode 100644 index 0000000000..6b2fe5dfe1 --- /dev/null +++ b/src/cmd/addr2line/main.c @@ -0,0 +1,68 @@ +// 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. + +/* + * addr2line simulation - only enough to make pprof work on Macs + */ + +#include +#include +#include +#include + +void +usage(void) +{ + fprint(2, "usage: addr2line binary\n"); + fprint(2, "reads addresses from standard input and writes two lines for each:\n"); + fprint(2, "\tfunction name\n"); + fprint(2, "\tfile:line\n"); + exits("usage"); +} + +void +main(int argc, char **argv) +{ + int fd; + char *p; + uvlong pc; + Symbol s; + Fhdr fhdr; + Biobuf bin, bout; + char file[1024]; + + ARGBEGIN{ + default: + usage(); + }ARGEND + + if(argc != 1) + usage(); + + fd = open(argv[0], OREAD); + if(fd < 0) + sysfatal("open %s: %r", argv[0]); + if(crackhdr(fd, &fhdr) <= 0) + sysfatal("crackhdr: %r"); + machbytype(fhdr.type); + if(syminit(fd, &fhdr) <= 0) + sysfatal("syminit: %r"); + + Binit(&bin, 0, OREAD); + Binit(&bout, 1, OWRITE); + for(;;) { + p = Brdline(&bin, '\n'); + if(p == nil) + break; + p[Blinelen(&bin)-1] = '\0'; + pc = strtoull(p, 0, 16); + if(!findsym(pc, CTEXT, &s)) + s.name = "??"; + if(!fileline(file, sizeof file, pc)) + strcpy(file, "??:0"); + Bprint(&bout, "%s\n%s\n", s.name, file); + } + Bflush(&bout); + exits(0); +} diff --git a/src/cmd/dist/build.c b/src/cmd/dist/build.c index 5664c1890a..66b5c1f183 100644 --- a/src/cmd/dist/build.c +++ b/src/cmd/dist/build.c @@ -59,7 +59,7 @@ int find(char *p, char **l, int n) { int i; - + for(i=0; i 0) bwriteb(&b, &bmore); @@ -249,14 +249,14 @@ findgoversion(void) done: p = btake(&b); - - + + bfree(&b); bfree(&path); bfree(&bmore); bfree(&branch); vfree(&tags); - + return p; } @@ -325,7 +325,7 @@ setup(void) xremoveall(p); xmkdirall(p); } - + // Create object directory. // We keep it in pkg/ so that all the generated binaries // are in one tree. If pkg/obj/libgc.a exists, it is a dreg from @@ -393,7 +393,7 @@ static char *proto_gccargs[] = { static Vec gccargs; // deptab lists changes to the default dependencies for a given prefix. -// deps ending in /* read the whole directory; deps beginning with - +// deps ending in /* read the whole directory; deps beginning with - // exclude files with that prefix. static struct { char *prefix; // prefix of target @@ -559,7 +559,7 @@ install(char *dir) vinit(&clean); vinit(&lib); vinit(&extra); - + // path = full path to dir. bpathf(&path, "%s/src/%s", goroot, dir); name = lastelem(dir); @@ -599,7 +599,7 @@ install(char *dir) exe = ""; if(streq(gohostos, "windows")) exe = ".exe"; - + // Start final link command line. // Note: code below knows that link.p[targ] is the target. if(islib) { @@ -696,13 +696,13 @@ install(char *dir) } files.len = n; continue; - } + } vadd(&files, p); } } } vuniq(&files); - + // Convert to absolute paths. for(i=0; i ttarg) stale = 1; - + if(!stale) goto out; @@ -792,9 +792,9 @@ install(char *dir) copy(bpathf(&b, "%s/zasm_GOOS_GOARCH.h", workdir), bpathf(&b1, "%s/zasm_%s_%s.h", bstr(&path), goos, goarch), 0); } - + // Generate .c files from .goc files. - if(streq(dir, "pkg/runtime")) { + if(streq(dir, "pkg/runtime")) { for(i=0; i 1) @@ -833,13 +833,13 @@ install(char *dir) vadd(&compile, "-m32"); if(streq(dir, "lib9")) vadd(&compile, "-DPLAN9PORT"); - + vadd(&compile, "-I"); vadd(&compile, bpathf(&b, "%s/include", goroot)); - + vadd(&compile, "-I"); vadd(&compile, bstr(&path)); - + // lib9/goos.c gets the default constants hard-coded. if(streq(name, "goos.c")) { vadd(&compile, bprintf(&b, "-DGOOS=\"%s\"", goos)); @@ -849,7 +849,7 @@ install(char *dir) vadd(&compile, bprintf(&b, "-DGOROOT=\"%s\"", bstr(&b1))); vadd(&compile, bprintf(&b, "-DGOVERSION=\"%s\"", goversion)); } - + // gc/lex.c records the GOEXPERIMENT setting used during the build. if(streq(name, "lex.c")) { xgetenv(&b, "GOEXPERIMENT"); @@ -867,7 +867,7 @@ install(char *dir) vadd(&compile, workdir); vadd(&compile, bprintf(&b, "-DGOOS_%s", goos)); vadd(&compile, bprintf(&b, "-DGOARCH_%s", goarch)); - } + } bpathf(&b, "%s/%s", workdir, lastelem(files.p[i])); doclean = 1; @@ -893,7 +893,7 @@ install(char *dir) vadd(&clean, bstr(&b)); } bgwait(); - + if(isgo) { // The last loop was compiling individual files. // Hand the Go files to the compiler en masse. @@ -905,16 +905,16 @@ install(char *dir) vadd(&compile, bstr(&b)); vadd(&clean, bstr(&b)); vadd(&link, bstr(&b)); - + vadd(&compile, "-p"); if(hasprefix(dir, "pkg/")) vadd(&compile, dir+4); else vadd(&compile, "main"); - + if(streq(dir, "pkg/runtime")) vadd(&compile, "-+"); - + vcopy(&compile, go.p, go.len); runv(nil, bstr(&path), CheckExit, &compile); @@ -980,7 +980,7 @@ shouldbuild(char *file, char *dir) int i, j, ret; Buf b; Vec lines, fields; - + // Check file name for GOOS or GOARCH. name = lastelem(file); for(i=0; i 1) xprintf("cp %s %s\n", src, dst); @@ -1070,11 +1070,13 @@ static char *buildorder[] = { "lib9", "libbio", "libmach", - + "misc/pprof", + "cmd/addr2line", "cmd/cov", "cmd/nm", + "cmd/objdump", "cmd/pack", "cmd/prof", @@ -1122,12 +1124,12 @@ static char *buildorder[] = { "pkg/go/scanner", "pkg/go/ast", "pkg/go/parser", - "pkg/go/build", "pkg/os/exec", "pkg/net/url", "pkg/text/template/parse", "pkg/text/template", "pkg/go/doc", + "pkg/go/build", "cmd/go", }; @@ -1147,11 +1149,13 @@ static char *cleantab[] = { "cmd/8c", "cmd/8g", "cmd/8l", + "cmd/addr2line", "cmd/cc", "cmd/cov", "cmd/gc", "cmd/go", "cmd/nm", + "cmd/objdump", "cmd/pack", "cmd/prof", "lib9", @@ -1204,11 +1208,11 @@ clean(void) int i, j, k; Buf b, path; Vec dir; - + binit(&b); binit(&path); vinit(&dir); - + for(i=0; i 0) usage(); - + xprintf(format, "GOROOT", goroot); xprintf(format, "GOBIN", gobin); xprintf(format, "GOARCH", goarch); @@ -1346,7 +1350,7 @@ cmdbootstrap(int argc, char **argv) clean(); goversion = findgoversion(); setup(); - + // For the main bootstrap, building for host os/arch. oldgoos = goos; oldgoarch = goarch; @@ -1356,7 +1360,7 @@ cmdbootstrap(int argc, char **argv) gochar = gohostchar; xsetenv("GOARCH", goarch); xsetenv("GOOS", goos); - + for(i=0; i +#include +#include +#include + +void +usage(void) +{ + fprint(2, "usage: objdump binary start stop\n"); + fprint(2, "Disassembles binary from PC start up to stop.\n"); + exits("usage"); +} + +void +main(int argc, char **argv) +{ + int fd, n; + uvlong pc, start, stop; + Fhdr fhdr; + Biobuf bout; + char buf[1024]; + Map *text; + + ARGBEGIN{ + default: + usage(); + }ARGEND + + if(argc != 3) + usage(); + start = strtoull(argv[1], 0, 16); + stop = strtoull(argv[2], 0, 16); + + fd = open(argv[0], OREAD); + if(fd < 0) + sysfatal("open %s: %r", argv[0]); + if(crackhdr(fd, &fhdr) <= 0) + sysfatal("crackhdr: %r"); + machbytype(fhdr.type); + if(syminit(fd, &fhdr) <= 0) + sysfatal("syminit: %r"); + text = loadmap(nil, fd, &fhdr); + if(text == nil) + sysfatal("loadmap: %r"); + + Binit(&bout, 1, OWRITE); + for(pc=start; pcdas(text, pc, 0, buf, sizeof buf); + Bprint(&bout, " %llx: %s\n", pc, buf); + n = machdata->instsize(text, pc); + if(n <= 0) + break; + pc += n; + } + Bflush(&bout); + exits(0); +} diff --git a/src/libmach/8db.c b/src/libmach/8db.c index 3101e13730..ce1b4ddd76 100644 --- a/src/libmach/8db.c +++ b/src/libmach/8db.c @@ -1,11 +1,11 @@ // Inferno libmach/8db.c // http://code.google.com/p/inferno-os/source/browse/utils/libmach/8db.c // -// Copyright © 1994-1999 Lucent Technologies Inc. -// Power PC support Copyright © 1995-2004 C H Forsyth (forsyth@terzarima.net). -// Portions Copyright © 1997-1999 Vita Nuova Limited. -// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com). -// Revisions Copyright © 2000-2004 Lucent Technologies Inc. and others. +// Copyright © 1994-1999 Lucent Technologies Inc. +// Power PC support Copyright © 1995-2004 C H Forsyth (forsyth@terzarima.net). +// Portions Copyright © 1997-1999 Vita Nuova Limited. +// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com). +// Revisions Copyright © 2000-2004 Lucent Technologies Inc. and others. // Portions Copyright © 2009 The Go Authors. All rights reserved. // // Permission is hereby granted, free of charge, to any person obtaining a copy @@ -2088,18 +2088,23 @@ immediate(Instr *ip, vlong val) static void pea(Instr *ip) { + int base; + + base = ip->base; + if(base >= 0 && (ip->rex & REXB)) + base += 8; + if (ip->mod == 3) { if (ip->osize == 'B') bprint(ip, (ip->rex & REXB? breg64: breg)[(uchar)ip->base]); - else if(ip->rex & REXB) - bprint(ip, "%s%s", ANAME(ip), reg[ip->base+8]); else - bprint(ip, "%s%s", ANAME(ip), reg[(uchar)ip->base]); + bprint(ip, "%s%s", ANAME(ip), reg[base]); return; } + if (ip->segment) bprint(ip, ip->segment); - if (ip->asize == 'E' && ip->base == SP) + if (ip->asize == 'E' && base == SP) plocal(ip); else { if (ip->base < 0) diff --git a/src/pkg/runtime/lock_futex.c b/src/pkg/runtime/lock_futex.c index 6ec4aee7bf..b4465bff18 100644 --- a/src/pkg/runtime/lock_futex.c +++ b/src/pkg/runtime/lock_futex.c @@ -118,8 +118,12 @@ runtime·notewakeup(Note *n) void runtime·notesleep(Note *n) { + if(m->profilehz > 0) + runtime·setprof(false); while(runtime·atomicload(&n->key) == 0) runtime·futexsleep(&n->key, 0, -1); + if(m->profilehz > 0) + runtime·setprof(true); } void @@ -135,14 +139,18 @@ runtime·notetsleep(Note *n, int64 ns) if(runtime·atomicload(&n->key) != 0) return; + if(m->profilehz > 0) + runtime·setprof(false); deadline = runtime·nanotime() + ns; for(;;) { runtime·futexsleep(&n->key, 0, ns); if(runtime·atomicload(&n->key) != 0) - return; + break; now = runtime·nanotime(); if(now >= deadline) - return; + break; ns = deadline - now; } + if(m->profilehz > 0) + runtime·setprof(true); } diff --git a/src/pkg/runtime/lock_sema.c b/src/pkg/runtime/lock_sema.c index 28d2c3281e..1d9c37fdb6 100644 --- a/src/pkg/runtime/lock_sema.c +++ b/src/pkg/runtime/lock_sema.c @@ -154,7 +154,11 @@ runtime·notesleep(Note *n) return; } // Queued. Sleep. + if(m->profilehz > 0) + runtime·setprof(false); runtime·semasleep(-1); + if(m->profilehz > 0) + runtime·setprof(true); } void @@ -178,12 +182,16 @@ runtime·notetsleep(Note *n, int64 ns) return; } + if(m->profilehz > 0) + runtime·setprof(false); deadline = runtime·nanotime() + ns; for(;;) { // Registered. Sleep. if(runtime·semasleep(ns) >= 0) { // Acquired semaphore, semawakeup unregistered us. // Done. + if(m->profilehz > 0) + runtime·setprof(true); return; } @@ -196,6 +204,9 @@ runtime·notetsleep(Note *n, int64 ns) ns = deadline - now; } + if(m->profilehz > 0) + runtime·setprof(true); + // Deadline arrived. Still registered. Semaphore not acquired. // Want to give up and return, but have to unregister first, // so that any notewakeup racing with the return does not diff --git a/src/pkg/runtime/os_darwin.h b/src/pkg/runtime/os_darwin.h index 071a547177..eb5d2daa38 100644 --- a/src/pkg/runtime/os_darwin.h +++ b/src/pkg/runtime/os_darwin.h @@ -38,4 +38,7 @@ void runtime·raisesigpipe(void); #define NSIG 32 #define SI_USER 0 /* empirically true, but not what headers say */ +#define SIG_BLOCK 1 +#define SIG_UNBLOCK 2 #define SIG_SETMASK 3 + diff --git a/src/pkg/runtime/os_freebsd.h b/src/pkg/runtime/os_freebsd.h index da1d8de2eb..5e8de5434a 100644 --- a/src/pkg/runtime/os_freebsd.h +++ b/src/pkg/runtime/os_freebsd.h @@ -9,7 +9,6 @@ struct sigaction; void runtime·sigaction(int32, struct sigaction*, struct sigaction*); void runtime·sigprocmask(Sigset *, Sigset *); void runtime·setsig(int32, void(*)(int32, Siginfo*, void*, G*), bool); -void runtiem·setitimerval(int32, Itimerval*, Itimerval*); void runtime·setitimer(int32, Itimerval*, Itimerval*); int32 runtime·sysctl(uint32*, uint32, byte*, uintptr*, byte*, uintptr); diff --git a/src/pkg/runtime/os_netbsd.h b/src/pkg/runtime/os_netbsd.h index 67c58ecb2a..4ecf78d882 100644 --- a/src/pkg/runtime/os_netbsd.h +++ b/src/pkg/runtime/os_netbsd.h @@ -12,7 +12,6 @@ void runtime·sigaltstack(Sigaltstack*, Sigaltstack*); void runtime·sigaction(int32, struct sigaction*, struct sigaction*); void runtime·setsig(int32, void(*)(int32, Siginfo*, void*, G*), bool); void runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp); -void runtime·setitimerval(int32, Itimerval*, Itimerval*); void runtime·setitimer(int32, Itimerval*, Itimerval*); int32 runtime·sysctl(uint32*, uint32, byte*, uintptr*, byte*, uintptr); diff --git a/src/pkg/runtime/os_openbsd.h b/src/pkg/runtime/os_openbsd.h index 67c58ecb2a..4ecf78d882 100644 --- a/src/pkg/runtime/os_openbsd.h +++ b/src/pkg/runtime/os_openbsd.h @@ -12,7 +12,6 @@ void runtime·sigaltstack(Sigaltstack*, Sigaltstack*); void runtime·sigaction(int32, struct sigaction*, struct sigaction*); void runtime·setsig(int32, void(*)(int32, Siginfo*, void*, G*), bool); void runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp); -void runtime·setitimerval(int32, Itimerval*, Itimerval*); void runtime·setitimer(int32, Itimerval*, Itimerval*); int32 runtime·sysctl(uint32*, uint32, byte*, uintptr*, byte*, uintptr); diff --git a/src/pkg/runtime/pprof/pprof.go b/src/pkg/runtime/pprof/pprof.go index 099bb6a92f..f67e8a8f9a 100644 --- a/src/pkg/runtime/pprof/pprof.go +++ b/src/pkg/runtime/pprof/pprof.go @@ -20,8 +20,8 @@ import ( "text/tabwriter" ) -// BUG(rsc): CPU profiling is broken on OS X, due to an Apple kernel bug. -// For details, see http://code.google.com/p/go/source/detail?r=35b716c94225. +// BUG(rsc): A bug in the OS X Snow Leopard 64-bit kernel prevents +// CPU profiling from giving accurate results on that system. // A Profile is a collection of stack traces showing the call sequences // that led to instances of a particular event, such as allocation. @@ -156,7 +156,7 @@ func (p *Profile) Count() int { } // Add adds the current execution stack to the profile, associated with value. -// Add stores value in an internal map, so value must be suitable for use as +// Add stores value in an internal map, so value must be suitable for use as // a map key and will not be garbage collected until the corresponding // call to Remove. Add panics if the profile already contains a stack for value. // diff --git a/src/pkg/runtime/pprof/pprof_test.go b/src/pkg/runtime/pprof/pprof_test.go index 5f128c01cf..994ec9dde4 100644 --- a/src/pkg/runtime/pprof/pprof_test.go +++ b/src/pkg/runtime/pprof/pprof_test.go @@ -7,6 +7,7 @@ package pprof_test import ( "bytes" "hash/crc32" + "os/exec" "runtime" . "runtime/pprof" "strings" @@ -17,8 +18,15 @@ import ( func TestCPUProfile(t *testing.T) { switch runtime.GOOS { case "darwin": - // see Apple Bug Report #9177434 (copied into change description) - return + out, err := exec.Command("uname", "-a").CombinedOutput() + if err != nil { + t.Fatal(err) + } + vers := string(out) + t.Logf("uname -a: %v", vers) + if strings.Contains(vers, "Darwin Kernel Version 10.8.0") && strings.Contains(vers, "root:xnu-1504.15.3~1/RELEASE_X86_64") { + t.Logf("skipping test on known-broken kernel (64-bit Snow Leopard)") + } case "plan9": // unimplemented return diff --git a/src/pkg/runtime/proc.c b/src/pkg/runtime/proc.c index d94bec8855..ddac048a00 100644 --- a/src/pkg/runtime/proc.c +++ b/src/pkg/runtime/proc.c @@ -338,7 +338,7 @@ mcommoninit(M *m) m->mcache = runtime·allocmcache(); runtime·callers(1, m->createstack, nelem(m->createstack)); - + // Add to runtime·allm so garbage collector doesn't free m // when it is just in a register or thread-local storage. m->alllink = runtime·allm; @@ -728,7 +728,6 @@ runtime·mstart(void) // so other calls can reuse this stack space. runtime·gosave(&m->g0->sched); m->g0->sched.pc = (void*)-1; // make sure it is never used - runtime·asminit(); runtime·minit(); schedule(nil); @@ -916,6 +915,9 @@ runtime·entersyscall(void) { uint32 v; + if(m->profilehz > 0) + runtime·setprof(false); + // Leave SP around for gc and traceback. runtime·gosave(&g->sched); g->gcsp = g->sched.sp; @@ -979,6 +981,9 @@ runtime·exitsyscall(void) // Garbage collector isn't running (since we are), // so okay to clear gcstack. g->gcstack = nil; + + if(m->profilehz > 0) + runtime·setprof(true); return; } diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h index 3b0f505e72..f2669fdb7e 100644 --- a/src/pkg/runtime/runtime.h +++ b/src/pkg/runtime/runtime.h @@ -730,3 +730,13 @@ bool runtime·showframe(Func*); void runtime·ifaceE2I(struct InterfaceType*, Eface, Iface*); uintptr runtime·memlimit(void); + +// If appropriate, ask the operating system to control whether this +// thread should receive profiling signals. This is only necessary on OS X. +// An operating system should not deliver a profiling signal to a +// thread that is not actually executing (what good is that?), but that's +// what OS X prefers to do. When profiling is turned on, we mask +// away the profiling signal when threads go to sleep, so that OS X +// is forced to deliver the signal to a thread that's actually running. +// This is a no-op on other systems. +void runtime·setprof(bool); diff --git a/src/pkg/runtime/signal_darwin_386.c b/src/pkg/runtime/signal_darwin_386.c index 1844f68a63..9e986352b4 100644 --- a/src/pkg/runtime/signal_darwin_386.c +++ b/src/pkg/runtime/signal_darwin_386.c @@ -40,7 +40,8 @@ runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp) r = &mc->ss; if(sig == SIGPROF) { - runtime·sigprof((uint8*)r->eip, (uint8*)r->esp, nil, gp); + if(gp != m->g0 && gp != m->gsignal) + runtime·sigprof((uint8*)r->eip, (uint8*)r->esp, nil, gp); return; } @@ -58,7 +59,7 @@ runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp) if(pc[0] == 0xF6 || pc[0] == 0xF7) info->si_code = FPE_INTDIV; } - + // Make it look like a call to the signal func. // Have to pass arguments out of band since // augmenting the stack frame would break diff --git a/src/pkg/runtime/signal_darwin_amd64.c b/src/pkg/runtime/signal_darwin_amd64.c index 32c73081c1..d9c5f48e7c 100644 --- a/src/pkg/runtime/signal_darwin_amd64.c +++ b/src/pkg/runtime/signal_darwin_amd64.c @@ -48,7 +48,8 @@ runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp) r = &mc->ss; if(sig == SIGPROF) { - runtime·sigprof((uint8*)r->rip, (uint8*)r->rsp, nil, gp); + if(gp != m->g0 && gp != m->gsignal) + runtime·sigprof((uint8*)r->rip, (uint8*)r->rsp, nil, gp); return; } @@ -68,7 +69,7 @@ runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp) if(pc[0] == 0xF6 || pc[0] == 0xF7) info->si_code = FPE_INTDIV; } - + // Make it look like a call to the signal func. // Have to pass arguments out of band since // augmenting the stack frame would break @@ -77,7 +78,7 @@ runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp) gp->sigcode0 = info->si_code; gp->sigcode1 = (uintptr)info->si_addr; gp->sigpc = r->rip; - + // Only push runtime·sigpanic if r->rip != 0. // If r->rip == 0, probably panicked because of a // call to a nil func. Not pushing that onto sp will @@ -92,7 +93,7 @@ runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp) r->rip = (uintptr)runtime·sigpanic; return; } - + if(info->si_code == SI_USER || (t->flags & SigNotify)) if(runtime·sigsend(sig)) return; diff --git a/src/pkg/runtime/signal_unix.c b/src/pkg/runtime/signal_unix.c index 13708415b9..0b9d2a55a1 100644 --- a/src/pkg/runtime/signal_unix.c +++ b/src/pkg/runtime/signal_unix.c @@ -55,17 +55,17 @@ void runtime·resetcpuprofiler(int32 hz) { Itimerval it; - + runtime·memclr((byte*)&it, sizeof it); if(hz == 0) { runtime·setitimer(ITIMER_PROF, &it, nil); - runtime·setsig(SIGPROF, SIG_IGN, true); + runtime·setprof(false); } else { - runtime·setsig(SIGPROF, runtime·sighandler, true); it.it_interval.tv_sec = 0; it.it_interval.tv_usec = 1000000 / hz; it.it_value = it.it_interval; runtime·setitimer(ITIMER_PROF, &it, nil); + runtime·setprof(true); } m->profilehz = hz; } diff --git a/src/pkg/runtime/sys_darwin_386.s b/src/pkg/runtime/sys_darwin_386.s index e235a8473d..c2dab8931c 100644 --- a/src/pkg/runtime/sys_darwin_386.s +++ b/src/pkg/runtime/sys_darwin_386.s @@ -100,14 +100,14 @@ TEXT runtime·nanotime(SB), 7, $32 IMULL $1000, BX ADDL BX, AX ADCL $0, DX - + MOVL ret+0(FP), DI MOVL AX, 0(DI) MOVL DX, 4(DI) RET TEXT runtime·sigprocmask(SB),7,$0 - MOVL $48, AX + MOVL $329, AX // pthread_sigmask (on OS X, sigprocmask==entire process) INT $0x80 JAE 2(PC) CALL runtime·notok(SB) diff --git a/src/pkg/runtime/sys_darwin_amd64.s b/src/pkg/runtime/sys_darwin_amd64.s index 13882c8524..4b215d04d4 100644 --- a/src/pkg/runtime/sys_darwin_amd64.s +++ b/src/pkg/runtime/sys_darwin_amd64.s @@ -96,7 +96,7 @@ TEXT runtime·sigprocmask(SB),7,$0 MOVL 8(SP), DI MOVQ 16(SP), SI MOVQ 24(SP), DX - MOVL $(0x2000000+48), AX // syscall entry + MOVL $(0x2000000+329), AX // pthread_sigmask (on OS X, sigprocmask==entire process) SYSCALL JCC 2(PC) CALL runtime·notok(SB) diff --git a/src/pkg/runtime/thread_darwin.c b/src/pkg/runtime/thread_darwin.c index d170dfb3d3..556fb67e84 100644 --- a/src/pkg/runtime/thread_darwin.c +++ b/src/pkg/runtime/thread_darwin.c @@ -11,6 +11,7 @@ extern SigTab runtime·sigtab[]; static Sigset sigset_all = ~(Sigset)0; static Sigset sigset_none; +static Sigset sigset_prof = 1<<(SIGPROF-1); static void unimplemented(int8 *name) @@ -23,7 +24,14 @@ unimplemented(int8 *name) int32 runtime·semasleep(int64 ns) { - return runtime·mach_semacquire(m->waitsema, ns); + int32 v; + + if(m->profilehz > 0) + runtime·setprof(false); + v = runtime·mach_semacquire(m->waitsema, ns); + if(m->profilehz > 0) + runtime·setprof(true); + return v; } void @@ -84,7 +92,7 @@ runtime·newosproc(M *m, G *g, void *stk, void (*fn)(void)) runtime·sigprocmask(SIG_SETMASK, &sigset_all, &oset); errno = runtime·bsdthread_create(stk, m, g, fn); runtime·sigprocmask(SIG_SETMASK, &oset, nil); - + if(errno < 0) { runtime·printf("runtime: failed to create new OS thread (have %d already; errno=%d)\n", runtime·mcount(), -errno); runtime·throw("runtime.newosproc"); @@ -98,7 +106,11 @@ runtime·minit(void) // Initialize signal handling. m->gsignal = runtime·malg(32*1024); // OS X wants >=8K, Linux >=2K runtime·signalstack(m->gsignal->stackguard - StackGuard, 32*1024); - runtime·sigprocmask(SIG_SETMASK, &sigset_none, nil); + + if(m->profilehz > 0) + runtime·sigprocmask(SIG_SETMASK, &sigset_none, nil); + else + runtime·sigprocmask(SIG_SETMASK, &sigset_prof, nil); } // Mach IPC, to get at semaphores @@ -434,3 +446,34 @@ runtime·memlimit(void) // the limit. return 0; } + +// NOTE(rsc): On OS X, when the CPU profiling timer expires, the SIGPROF +// signal is not guaranteed to be sent to the thread that was executing to +// cause it to expire. It can and often does go to a sleeping thread, which is +// not interesting for our profile. This is filed Apple Bug Report #9177434, +// copied to http://code.google.com/p/go/source/detail?r=35b716c94225. +// To work around this bug, we disable receipt of the profiling signal on +// a thread while in blocking system calls. This forces the kernel to deliver +// the profiling signal to an executing thread. +// +// The workaround fails on OS X machines using a 64-bit Snow Leopard kernel. +// In that configuration, the kernel appears to want to deliver SIGPROF to the +// sleeping threads regardless of signal mask and, worse, does not deliver +// the signal until the thread wakes up on its own. +// +// If necessary, we can switch to using ITIMER_REAL for OS X and handle +// the kernel-generated SIGALRM by generating our own SIGALRMs to deliver +// to all the running threads. SIGALRM does not appear to be affected by +// the 64-bit Snow Leopard bug. However, as of this writing Mountain Lion +// is in preview, making Snow Leopard two versions old, so it is unclear how +// much effort we need to spend on one buggy kernel. + +// Control whether profiling signal can be delivered to this thread. +void +runtime·setprof(bool on) +{ + if(on) + runtime·sigprocmask(SIG_UNBLOCK, &sigset_prof, nil); + else + runtime·sigprocmask(SIG_BLOCK, &sigset_prof, nil); +} diff --git a/src/pkg/runtime/thread_freebsd.c b/src/pkg/runtime/thread_freebsd.c index 7871827a97..77e8bb3dac 100644 --- a/src/pkg/runtime/thread_freebsd.c +++ b/src/pkg/runtime/thread_freebsd.c @@ -189,3 +189,9 @@ runtime·memlimit(void) return rl.rlim_cur - used; } + +void +runtime·setprof(bool on) +{ + USED(on); +} diff --git a/src/pkg/runtime/thread_linux.c b/src/pkg/runtime/thread_linux.c index d406a71240..6b428440e0 100644 --- a/src/pkg/runtime/thread_linux.c +++ b/src/pkg/runtime/thread_linux.c @@ -228,7 +228,7 @@ runtime·memlimit(void) Rlimit rl; extern byte text[], end[]; uintptr used; - + if(runtime·getrlimit(RLIMIT_AS, &rl) != 0) return 0; if(rl.rlim_cur >= 0x7fffffff) @@ -249,3 +249,9 @@ runtime·memlimit(void) return rl.rlim_cur - used; } + +void +runtime·setprof(bool on) +{ + USED(on); +} diff --git a/src/pkg/runtime/thread_netbsd.c b/src/pkg/runtime/thread_netbsd.c index 7d14e5c68b..62e133c449 100644 --- a/src/pkg/runtime/thread_netbsd.c +++ b/src/pkg/runtime/thread_netbsd.c @@ -207,3 +207,9 @@ runtime·memlimit(void) { return 0; } + +void +runtime·setprof(bool on) +{ + USED(on); +} diff --git a/src/pkg/runtime/thread_openbsd.c b/src/pkg/runtime/thread_openbsd.c index 704d95a3c6..bee0c5755f 100644 --- a/src/pkg/runtime/thread_openbsd.c +++ b/src/pkg/runtime/thread_openbsd.c @@ -207,3 +207,9 @@ runtime·memlimit(void) { return 0; } + +void +runtime·setprof(bool on) +{ + USED(on); +} diff --git a/src/pkg/runtime/thread_plan9.c b/src/pkg/runtime/thread_plan9.c index 7d5c38fc9a..aaed5050bb 100644 --- a/src/pkg/runtime/thread_plan9.c +++ b/src/pkg/runtime/thread_plan9.c @@ -87,7 +87,7 @@ runtime·nanotime(void) // The naïve implementation (without the cached // file descriptor) is roughly four times slower // in 9vx on a 2.16 GHz Intel Core 2 Duo. - + if(fd < 0 && (fd = runtime·open((byte*)"/dev/bintime", OREAD|OCEXEC)) < 0) return 0; if(runtime·pread(fd, b, sizeof b, 0) != sizeof b) @@ -241,3 +241,9 @@ runtime·memlimit(void) { return 0; } + +void +runtime·setprof(bool on) +{ + USED(on); +} diff --git a/src/pkg/runtime/thread_windows.c b/src/pkg/runtime/thread_windows.c index 8feac9711d..8a448bc37c 100644 --- a/src/pkg/runtime/thread_windows.c +++ b/src/pkg/runtime/thread_windows.c @@ -226,7 +226,7 @@ void time·now(int64 sec, int32 usec) { int64 ns; - + ns = runtime·nanotime(); sec = ns / 1000000000LL; usec = ns - sec * 1000000000LL; @@ -431,3 +431,9 @@ runtime·memlimit(void) { return 0; } + +void +runtime·setprof(bool on) +{ + USED(on); +}