aboutsummaryrefslogtreecommitdiff
path: root/src/runtime/debuglog.go
AgeCommit message (Collapse)Author
2025-11-18runtime: add dlog.hexdumpAustin Clements
Change-Id: I8149ab9314216bb8f9bf58da55633e2587d75851 Reviewed-on: https://go-review.googlesource.com/c/go/+/681376 Auto-Submit: Austin Clements <austin@google.com> Reviewed-by: Michael Pratt <mpratt@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-07-29internal/abi: move direct/indirect flag from Kind to TFlagKeith Randall
This info makes more sense in the flags instead of as a high bit of the kind. This makes kind access simpler because we now don't need to mask anything. Cleaned up most direct field accesses to use methods instead. (reflect making new types is the only remaining direct accessor.) IfaceIndir -> !IsDirectIface everywhere. gocore has been updated to handle the new location. So has delve. TODO: any other tools need updating? Change-Id: I123f97a4d4bdd0bff1641ee7e276d1cc0bd7e8eb Reviewed-on: https://go-review.googlesource.com/c/go/+/681936 Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: David Chase <drchase@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-04-08runtime: use internal/byteorderapocelipes
To simplify the code. Change-Id: Ib1af5009cc25bb29fd26fdb7b29ff4579f0150aa GitHub-Last-Rev: f698a8a771ac8c6ecb745ea4c27a7c677c1789d1 GitHub-Pull-Request: golang/go#73255 Reviewed-on: https://go-review.googlesource.com/c/go/+/663735 Reviewed-by: Carlos Amedee <carlos@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-03-04runtime: decorate anonymous memory mappingsLénaïc Huard
Leverage the prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, ...) API to name the anonymous memory areas. This API has been introduced in Linux 5.17 to decorate the anonymous memory areas shown in /proc/<pid>/maps. This is already used by glibc. See: * https://sourceware.org/git/?p=glibc.git;a=blob;f=malloc/malloc.c;h=27dfd1eb907f4615b70c70237c42c552bb4f26a8;hb=HEAD#l2434 * https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/setvmaname.c;h=ea93a5ffbebc9e5a7e32a297138f465724b4725f;hb=HEAD#l63 This can be useful when investigating the memory consumption of a multi-language program. On a 100% Go program, pprof profiler can be used to profile the memory consumption of the program. But pprof is only aware of what happens within the Go world. On a multi-language program, there could be a doubt about whether the suspicious extra-memory consumption comes from the Go part or the native part. With this change, the following Go program: package main import ( "fmt" "log" "os" ) /* #include <stdlib.h> void f(void) { (void)malloc(1024*1024*1024); } */ import "C" func main() { C.f() data, err := os.ReadFile("/proc/self/maps") if err != nil { log.Fatal(err) } fmt.Println(string(data)) } produces this output: $ GLIBC_TUNABLES=glibc.mem.decorate_maps=1 ~/doc/devel/open-source/go/bin/go run . 00400000-00402000 r--p 00000000 00:21 28451768 /home/lenaic/.cache/go-build/9f/9f25a17baed5a80d03eb080a2ce2a5ff49c17f9a56e28330f0474a2bb74a30a0-d/test_vma_name 00402000-004a4000 r-xp 00002000 00:21 28451768 /home/lenaic/.cache/go-build/9f/9f25a17baed5a80d03eb080a2ce2a5ff49c17f9a56e28330f0474a2bb74a30a0-d/test_vma_name 004a4000-00574000 r--p 000a4000 00:21 28451768 /home/lenaic/.cache/go-build/9f/9f25a17baed5a80d03eb080a2ce2a5ff49c17f9a56e28330f0474a2bb74a30a0-d/test_vma_name 00574000-00575000 r--p 00173000 00:21 28451768 /home/lenaic/.cache/go-build/9f/9f25a17baed5a80d03eb080a2ce2a5ff49c17f9a56e28330f0474a2bb74a30a0-d/test_vma_name 00575000-00580000 rw-p 00174000 00:21 28451768 /home/lenaic/.cache/go-build/9f/9f25a17baed5a80d03eb080a2ce2a5ff49c17f9a56e28330f0474a2bb74a30a0-d/test_vma_name 00580000-005a4000 rw-p 00000000 00:00 0 2e075000-2e096000 rw-p 00000000 00:00 0 [heap] c000000000-c000400000 rw-p 00000000 00:00 0 [anon: Go: heap] c000400000-c004000000 ---p 00000000 00:00 0 [anon: Go: heap reservation] 777f40000000-777f40021000 rw-p 00000000 00:00 0 [anon: glibc: malloc arena] 777f40021000-777f44000000 ---p 00000000 00:00 0 777f44000000-777f44021000 rw-p 00000000 00:00 0 [anon: glibc: malloc arena] 777f44021000-777f48000000 ---p 00000000 00:00 0 777f48000000-777f48021000 rw-p 00000000 00:00 0 [anon: glibc: malloc arena] 777f48021000-777f4c000000 ---p 00000000 00:00 0 777f4c000000-777f4c021000 rw-p 00000000 00:00 0 [anon: glibc: malloc arena] 777f4c021000-777f50000000 ---p 00000000 00:00 0 777f50000000-777f50021000 rw-p 00000000 00:00 0 [anon: glibc: malloc arena] 777f50021000-777f54000000 ---p 00000000 00:00 0 777f55afb000-777f55afc000 ---p 00000000 00:00 0 777f55afc000-777f562fc000 rw-p 00000000 00:00 0 [anon: glibc: pthread stack: 216378] 777f562fc000-777f562fd000 ---p 00000000 00:00 0 777f562fd000-777f56afd000 rw-p 00000000 00:00 0 [anon: glibc: pthread stack: 216377] 777f56afd000-777f56afe000 ---p 00000000 00:00 0 777f56afe000-777f572fe000 rw-p 00000000 00:00 0 [anon: glibc: pthread stack: 216376] 777f572fe000-777f572ff000 ---p 00000000 00:00 0 777f572ff000-777f57aff000 rw-p 00000000 00:00 0 [anon: glibc: pthread stack: 216375] 777f57aff000-777f57b00000 ---p 00000000 00:00 0 777f57b00000-777f58300000 rw-p 00000000 00:00 0 [anon: glibc: pthread stack: 216374] 777f58300000-777f58400000 rw-p 00000000 00:00 0 [anon: Go: page alloc index] 777f58400000-777f5a400000 rw-p 00000000 00:00 0 [anon: Go: heap index] 777f5a400000-777f6a580000 ---p 00000000 00:00 0 [anon: Go: scavenge index] 777f6a580000-777f6a581000 rw-p 00000000 00:00 0 [anon: Go: scavenge index] 777f6a581000-777f7a400000 ---p 00000000 00:00 0 [anon: Go: scavenge index] 777f7a400000-777f8a580000 ---p 00000000 00:00 0 [anon: Go: page summary] 777f8a580000-777f8a581000 rw-p 00000000 00:00 0 [anon: Go: page alloc] 777f8a581000-777f9c430000 ---p 00000000 00:00 0 [anon: Go: page summary] 777f9c430000-777f9c431000 rw-p 00000000 00:00 0 [anon: Go: page alloc] 777f9c431000-777f9e806000 ---p 00000000 00:00 0 [anon: Go: page summary] 777f9e806000-777f9e807000 rw-p 00000000 00:00 0 [anon: Go: page alloc] 777f9e807000-777f9ec00000 ---p 00000000 00:00 0 [anon: Go: page summary] 777f9ec36000-777f9ecb6000 rw-p 00000000 00:00 0 [anon: Go: immortal metadata] 777f9ecb6000-777f9ecc6000 rw-p 00000000 00:00 0 [anon: Go: gc bits] 777f9ecc6000-777f9ecd6000 rw-p 00000000 00:00 0 [anon: Go: allspans array] 777f9ecd6000-777f9ece7000 rw-p 00000000 00:00 0 [anon: Go: immortal metadata] 777f9ece7000-777f9ed67000 ---p 00000000 00:00 0 [anon: Go: page summary] 777f9ed67000-777f9ed68000 rw-p 00000000 00:00 0 [anon: Go: page alloc] 777f9ed68000-777f9ede7000 ---p 00000000 00:00 0 [anon: Go: page summary] 777f9ede7000-777f9ee07000 rw-p 00000000 00:00 0 [anon: Go: page alloc] 777f9ee07000-777f9ee0a000 rw-p 00000000 00:00 0 [anon: glibc: loader malloc] 777f9ee0a000-777f9ee2e000 r--p 00000000 00:21 48158213 /usr/lib/libc.so.6 777f9ee2e000-777f9ef9f000 r-xp 00024000 00:21 48158213 /usr/lib/libc.so.6 777f9ef9f000-777f9efee000 r--p 00195000 00:21 48158213 /usr/lib/libc.so.6 777f9efee000-777f9eff2000 r--p 001e3000 00:21 48158213 /usr/lib/libc.so.6 777f9eff2000-777f9eff4000 rw-p 001e7000 00:21 48158213 /usr/lib/libc.so.6 777f9eff4000-777f9effc000 rw-p 00000000 00:00 0 777f9effc000-777f9effe000 rw-p 00000000 00:00 0 [anon: glibc: loader malloc] 777f9f00a000-777f9f04a000 rw-p 00000000 00:00 0 [anon: Go: immortal metadata] 777f9f04a000-777f9f04c000 r--p 00000000 00:00 0 [vvar] 777f9f04c000-777f9f04e000 r--p 00000000 00:00 0 [vvar_vclock] 777f9f04e000-777f9f050000 r-xp 00000000 00:00 0 [vdso] 777f9f050000-777f9f051000 r--p 00000000 00:21 48158204 /usr/lib/ld-linux-x86-64.so.2 777f9f051000-777f9f07a000 r-xp 00001000 00:21 48158204 /usr/lib/ld-linux-x86-64.so.2 777f9f07a000-777f9f085000 r--p 0002a000 00:21 48158204 /usr/lib/ld-linux-x86-64.so.2 777f9f085000-777f9f087000 r--p 00034000 00:21 48158204 /usr/lib/ld-linux-x86-64.so.2 777f9f087000-777f9f088000 rw-p 00036000 00:21 48158204 /usr/lib/ld-linux-x86-64.so.2 777f9f088000-777f9f089000 rw-p 00000000 00:00 0 7ffc7bfa7000-7ffc7bfc8000 rw-p 00000000 00:00 0 [stack] ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0 [vsyscall] The anonymous memory areas are now labelled so that we can see which ones have been allocated by the Go runtime versus which ones have been allocated by the glibc. Fixes #71546 Change-Id: I304e8b4dd7f2477a6da794fd44e9a7a5354e4bf4 Reviewed-on: https://go-review.googlesource.com/c/go/+/646095 Auto-Submit: Alan Donovan <adonovan@google.com> Commit-Queue: Alan Donovan <adonovan@google.com> Reviewed-by: Felix Geisendörfer <felix.geisendoerfer@datadoghq.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2024-07-30runtime: run debuglog tests when debuglog tag is *not* setAustin Clements
Currently, the debuglog tests only run when the debuglog build tag is set because, until the last few CLs, all of debuglog was compiled away without that build tag. This causes two annoying problems: 1. The tests basically never run, because we don't regularly test this configuration. 2. If you do turn on the debuglog build tag, it's probably because you're adding debuglogs into the runtime, which are very likely to mess up these tests, so you wind up disabling the tests and they, again, don't get coverage. Now we've set things up so the debuglog implementation is always accessible, if you ask nicely enough. So we can switch these tests to run when the tag is *not* set, and turn off when the tag *is* set (and you're probably adding actual log statements). Change-Id: Ib68d7a5022d4f5db96e9c7c8010cbef21d11fe11 Reviewed-on: https://go-review.googlesource.com/c/go/+/600697 LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Carlos Amedee <carlos@golang.org>
2024-07-30runtime: switch debuglog from const-toggled to type-toggledAustin Clements
Currently, the debuglog build tag controls the dlogEnabled const, and all methods of dlogger first check this const and immediately return if dlog is not enabled. With constant folding and inlining, this makes the whole dlog implementation compile away if it's not enabled. However, we want to be able to test debuglog even when the build tag isn't set. For that to work, we need a different mechanism. This CL changes this mechanism so the debuglog build tag instead controls the type alias for dlogger to be either dloggerImpl or dloggerFake. These two types have the same method set, but one is just stubs. This way, the methods of dloggerImpl don't need to be conditional dlogEnabled, which sets us up to use the now fully-functional dloggerImpl type in the test. I confirmed that this change has no effect on the final size of the cmd/go binary. It does increase the size of the runtime.a file by 0.9% and make the runtime take ever so slightly longer to compile because the compiler can no longer simply eliminate the bodies of the all of dlogger during early deadcode. However, this all gets eliminated by the linker. I consider this worth it to always get build and test coverage of debuglog. Change-Id: I81759e9e1411b7d369a23383a18b022ab7451421 Reviewed-on: https://go-review.googlesource.com/c/go/+/600696 Reviewed-by: Carlos Amedee <carlos@golang.org> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-07-30runtime: rename dlogger to dloggerImplAustin Clements
This is a mechanical change, other than adding the type alias for dlogger. This is a step in preparing us to make debuglog testable without the debuglog build tag. Change-Id: Ief12f0eaf5db98a8b006c759fd325dabcc9a52d4 Reviewed-on: https://go-review.googlesource.com/c/go/+/600695 Reviewed-by: Carlos Amedee <carlos@golang.org> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-07-23runtime,internal: move runtime/internal/sys to internal/runtime/sysDavid Chase
Cleanup and friction reduction For #65355. Change-Id: Ia14c9dc584a529a35b97801dd3e95b9acc99a511 Reviewed-on: https://go-review.googlesource.com/c/go/+/600436 Reviewed-by: Keith Randall <khr@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org>
2024-04-02all: use kind* of abiqiulaidongfeng
For #59670 Change-Id: Id66e102f13e529dd041b68ce869026a56f0a1b9b GitHub-Last-Rev: 43aa9376f72bc02a9d86518cdc99494a6b2f8573 GitHub-Pull-Request: golang/go#65564 Reviewed-on: https://go-review.googlesource.com/c/go/+/562298 LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Austin Clements <austin@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Auto-Submit: Austin Clements <austin@google.com>
2024-03-25runtime: migrate internal/atomic to internal/runtimeAndy Pan
For #65355 Change-Id: I65dd090fb99de9b231af2112c5ccb0eb635db2be Reviewed-on: https://go-review.googlesource.com/c/go/+/560155 Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Michael Pratt <mpratt@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Ibrahim Bazoka <ibrahimbazoka729@gmail.com> Auto-Submit: Emmanuel Odeke <emmanuel@orijtech.com>
2023-05-05internal/abi: refactor (basic) type struct into one definitionDavid Chase
This touches a lot of files, which is bad, but it is also good, since there's N copies of this information commoned into 1. The new files in internal/abi are copied from the end of the stack; ultimately this will all end up being used. Change-Id: Ia252c0055aaa72ca569411ef9f9e96e3d610889e Reviewed-on: https://go-review.googlesource.com/c/go/+/462995 TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Carlos Amedee <carlos@golang.org> Run-TryBot: David Chase <drchase@google.com> Reviewed-by: Keith Randall <khr@golang.org>
2022-10-18runtime: avoid unsafe.{Slice,String} in debuglogMichael Pratt
CL 428157 and CL 428759 switched debuglog to using unsafe.String and unsafe.Slice, which broke the build with -tags=debuglog because this is a no write barrier context, but runtime.unsafeString and unsafeSlice can panic, which includes write barriers. We could add a panicCheck1 path to these functions to reallow write barriers, but it is a big mess to pass around the caller PC, particularly since the compiler generates calls. It is much simpler to just avoid unsafe.String and Slice. Also add a basic test to build the runtime with -tags=debuglog to help avoid future regressions. For #54854. Change-Id: I702418b986fbf189664e9aa4f40bc7de4d9e7781 Reviewed-on: https://go-review.googlesource.com/c/go/+/443380 Run-TryBot: Michael Pratt <mpratt@google.com> Auto-Submit: Michael Pratt <mpratt@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Michael Knyszek <mknyszek@google.com>
2022-09-13runtime: replace stringStruct with unsafe.String where appropriateCuong Manh Le
Simplify the code a bit, no significant performance changes. name old time/op new time/op delta HashStringSpeed-8 9.64ns ±11% 8.91ns ± 9% -7.60% (p=0.007 n=10+10) HashStringArraySpeed-8 19.8ns ± 3% 19.5ns ± 2% ~ (p=0.085 n=10+10) MapStringKeysEight_16-8 10.7ns ± 3% 10.2ns ± 2% -4.48% (p=0.000 n=10+10) MapStringKeysEight_32-8 8.89ns ± 3% 8.71ns ± 3% ~ (p=0.082 n=9+10) MapStringKeysEight_64-8 8.84ns ± 2% 8.60ns ± 3% -2.73% (p=0.004 n=9+10) MapStringKeysEight_1M-8 8.90ns ± 3% 8.62ns ± 3% -3.15% (p=0.000 n=10+10) MapStringConversion/32/simple-8 8.62ns ± 3% 8.61ns ± 2% ~ (p=0.895 n=10+10) MapStringConversion/32/struct-8 8.53ns ± 2% 8.63ns ± 2% ~ (p=0.123 n=10+10) MapStringConversion/32/array-8 8.54ns ± 2% 8.50ns ± 1% ~ (p=0.590 n=9+9) MapStringConversion/64/simple-8 8.44ns ± 2% 8.38ns ± 2% ~ (p=0.353 n=10+10) MapStringConversion/64/struct-8 8.41ns ± 2% 8.48ns ± 2% ~ (p=0.143 n=10+10) MapStringConversion/64/array-8 8.42ns ± 2% 8.44ns ± 2% ~ (p=0.739 n=10+10) MapInterfaceString-8 13.6ns ±26% 13.6ns ±20% ~ (p=0.736 n=10+9) AppendGrowString-8 38.9ms ± 9% 40.2ms ±13% ~ (p=0.481 n=10+10) CompareStringEqual-8 3.03ns ± 2% 2.86ns ± 3% -5.58% (p=0.000 n=10+10) CompareStringIdentical-8 1.20ns ± 3% 1.01ns ± 4% -16.16% (p=0.000 n=10+10) CompareStringSameLength-8 2.11ns ± 3% 1.85ns ± 3% -12.33% (p=0.000 n=10+10) CompareStringDifferentLength-8 0.30ns ± 0% 0.30ns ± 0% ~ (p=0.508 n=10+9) CompareStringBigUnaligned-8 43.0µs ± 1% 42.8µs ± 2% ~ (p=0.165 n=10+10) CompareStringBig-8 43.2µs ± 2% 43.4µs ± 2% ~ (p=0.661 n=9+10) ConcatStringAndBytes-8 15.1ns ± 1% 14.9ns ± 1% -1.57% (p=0.001 n=8+10) SliceByteToString/1-8 2.45ns ± 2% 2.39ns ± 2% -2.64% (p=0.000 n=10+10) SliceByteToString/2-8 10.9ns ± 2% 10.8ns ± 4% ~ (p=0.060 n=10+10) SliceByteToString/4-8 11.9ns ± 0% 11.8ns ± 1% -0.97% (p=0.000 n=8+8) SliceByteToString/8-8 13.9ns ± 1% 13.9ns ± 1% +0.57% (p=0.009 n=9+9) SliceByteToString/16-8 18.0ns ± 3% 18.6ns ± 5% +2.78% (p=0.001 n=9+10) SliceByteToString/32-8 20.1ns ± 3% 20.5ns ± 5% +2.10% (p=0.034 n=10+10) SliceByteToString/64-8 24.3ns ± 3% 24.9ns ± 3% +2.28% (p=0.001 n=9+10) SliceByteToString/128-8 33.8ns ± 1% 34.5ns ± 4% ~ (p=0.264 n=8+10) Updates #54854 Change-Id: I7ce57a92c5f590fa8cb31a48969d281147eb05f1 Reviewed-on: https://go-review.googlesource.com/c/go/+/428759 Reviewed-by: hopehook <hopehook@golangcn.org> Reviewed-by: Keith Randall <khr@google.com> Run-TryBot: Ian Lance Taylor <iant@google.com> Auto-Submit: Ian Lance Taylor <iant@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: Ian Lance Taylor <iant@google.com>
2022-09-07runtime: simplify code using unsafe.{Slice,String}cuiweixie
Updates #54854 Change-Id: Ie18665e93e477b6f220acf4c6c070b2af4343064 Reviewed-on: https://go-review.googlesource.com/c/go/+/428157 Run-TryBot: Ian Lance Taylor <iant@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@google.com> Reviewed-by: Bryan Mills <bcmills@google.com> Auto-Submit: Ian Lance Taylor <iant@google.com>
2022-08-26runtime: convert dlogger.owned to atomic typehopehook
Note that this changes a non-atomic operation to atomic operation. For #53821 Change-Id: I798914f505c8d7f85f9d7629fdc6493363a20aa1 Reviewed-on: https://go-review.googlesource.com/c/go/+/425782 Run-TryBot: Michael Pratt <mpratt@google.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> Run-TryBot: hopehook <hopehook@qq.com> TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com>
2022-08-19runtime: add and use runtime/internal/sys.NotInHeapCuong Manh Le
Updates #46731 Change-Id: Ic2208c8bb639aa1e390be0d62e2bd799ecf20654 Reviewed-on: https://go-review.googlesource.com/c/go/+/421878 Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2022-06-03runtime: avoid string allocation in printDebuglogMichael Anthony Knyszek
Either due to a new nowritebarrierrec annotation or a change in escape analysis, printDebuglog can't be called from sighandler anymore. Fix this by avoiding a string allocation that's the primary culprit. Change-Id: Ic84873a453f45852b0443a46597ed3ab8c9443fd Reviewed-on: https://go-review.googlesource.com/c/go/+/410121 Run-TryBot: Michael Knyszek <mknyszek@google.com> Reviewed-by: Michael Pratt <mpratt@google.com> TryBot-Result: Gopher Robot <gobot@golang.org>
2022-05-03runtime: track how much memory is mapped in the Ready stateMichael Anthony Knyszek
This change adds a field to memstats called mappedReady that tracks how much memory is in the Ready state at any given time. In essence, it's the total memory usage by the Go runtime (with one exception which is documented). Essentially, all memory mapped read/write that has either been paged in or will soon. To make tracking this not involve the many different stats that track mapped memory, we track this statistic at a very low level. The downside of tracking this statistic at such a low level is that it managed to catch lots of situations where the runtime wasn't fully accounting for memory. This change rectifies these situations by always accounting for memory that's mapped in some way (i.e. always passing a sysMemStat to a mem.go function), with *two* exceptions. Rectifying these situations means also having the memory mapped during testing being accounted for, so that tests (i.e. ReadMemStats) that ultimately check mappedReady continue to work correctly without special exceptions. We choose to simply account for this memory in other_sys. Let's talk about the exceptions. The first is the arenas array for finding heap arena metadata from an address is mapped as read/write in one large chunk. It's tens of MiB in size. On systems with demand paging, we assume that the whole thing isn't paged in at once (after all, it maps to the whole address space, and it's exceedingly difficult with today's technology to even broach having as much physical memory as the total address space). On systems where we have to commit memory manually, we use a two-level structure. Now, the reason why this is an exception is because we have no mechanism to track what memory is paged in, and we can't just account for the entire thing, because that would *look* like an enormous overhead. Furthermore, this structure is on a few really, really critical paths in the runtime, so doing more explicit tracking isn't really an option. So, we explicitly don't and call sysAllocOS to map this memory. The second exception is that we call sysFree with no accounting to clean up address space reservations, or otherwise to throw out mappings we don't care about. In this case, also drop down to a lower level and call sysFreeOS to explicitly avoid accounting. The third exception is debuglog allocations. That is purely a debugging facility and ideally we want it to have as small an impact on the runtime as possible. If we include it in mappedReady calculations, it could cause GC pacing shifts in future CLs, especailly if one increases the debuglog buffer sizes as a one-off. As of this CL, these are the only three places in the runtime that would pass nil for a stat to any of the functions in mem.go. As a result, this CL makes sysMemStats mandatory to facilitate better accounting in the future. It's now much easier to grep and find out where accounting is explicitly elided, because one doesn't have to follow the trail of sysMemStat nil pointer values, and can just look at the function name. For #48409. Change-Id: I274eb467fc2603881717482214fddc47c9eaf218 Reviewed-on: https://go-review.googlesource.com/c/go/+/393402 Reviewed-by: Michael Pratt <mpratt@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> Run-TryBot: Michael Knyszek <mknyszek@google.com>
2021-12-13all: gofmt -w -r 'interface{} -> any' srcRuss Cox
And then revert the bootstrap cmd directories and certain testdata. And adjust tests as needed. Not reverting the changes in std that are bootstrapped, because some of those changes would appear in API docs, and we want to use any consistently. Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories when preparing the bootstrap copy. A few files changed as a result of running gofmt -w not because of interface{} -> any but because they hadn't been updated for the new //go:build lines. Fixes #49884. Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09 Reviewed-on: https://go-review.googlesource.com/c/go/+/368254 Trust: Russ Cox <rsc@golang.org> Run-TryBot: Russ Cox <rsc@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org> TryBot-Result: Gopher Robot <gobot@golang.org>
2021-09-27runtime: convert _func.entry to a methodJosh Bleecher Snyder
A subsequent change will alter the semantics of _func.entry. To make that change obvious and clear, change _func.entry to a method, and rename the field to _func.entryPC. Change-Id: I05d66b54d06c5956d4537b0729ddf4290c3e2635 Reviewed-on: https://go-review.googlesource.com/c/go/+/351460 Trust: Josh Bleecher Snyder <josharian@gmail.com> Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com>
2020-04-29runtime: fix debuglog traceback printing off-by-oneAustin Clements
The debuglog traceback printer wasn't adjusting for call/return PCs. Change-Id: I98dda1c0f22cd78651d88124ea51dc166dc91c7a Reviewed-on: https://go-review.googlesource.com/c/go/+/227646 Run-TryBot: Austin Clements <austin@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Michael Knyszek <mknyszek@google.com>
2019-04-05runtime: fix typo in debuglog commentAustin Clements
Change-Id: I8a40461b93eab034ed930e0c5e32391f84cdbc5a Reviewed-on: https://go-review.googlesource.com/c/go/+/170799 Reviewed-by: Ian Lance Taylor <iant@golang.org> Reviewed-by: Sebastien Binet <seb.binet@gmail.com>
2019-04-04runtime: ring buffer for binary debug loggingAustin Clements
This adds an internal runtime debug log. It uses per-M time-stamped ring buffers of binary log records. On panic, these buffers are collected, interleaved, and printed. The entry-point to the debug log is a new "dlog" function. dlog is designed so it can be used even from very constrained corners of the runtime such as signal handlers or inside the write barrier. The facility is only enabled if the debuglog build tag is set. Otherwise, it compiles away to a no-op implementation. The debug log format is also designed so it would be reasonable to decode from a core dump, though this hasn't been implemented. Change-Id: I6e2737c286358e97a0d8091826498070b95b66a3 Reviewed-on: https://go-review.googlesource.com/c/go/+/157997 Run-TryBot: Austin Clements <austin@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Michael Knyszek <mknyszek@google.com>