Commit Graph

3805 Commits

Author SHA1 Message Date
Ian Lance Taylor 1531192272 runtime: remove VDSO fallback test and benchmarks
These tests assume that it is OK to switch between time implementations,
but the clock_gettime call uses CLOCK_MONOTONIC and the fallback call,
gettimeofday, uses CLOCK_REALTIME. Disabling the clock_gettime call means
that calls to nanotime will start returning very different values.
This breaks the new timer code, which assumes that nanotime will return
a consistently increasing value.

This test is not very useful in any case as it doesn't check the results.

Removing this file also removes BenchmarkTimeNow, which is a duplicate
of BenchmarkNow in the time package.

Updates #27707
Fixes #32109

Change-Id: I6a884af07f75822d724193c5eed94742f524f07d
Reviewed-on: https://go-review.googlesource.com/c/go/+/174679
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-27 17:58:39 +00:00
Cherry Zhang 496b8dbbfc cmd, runtime: remove PC_F & PC_B globals on Wasm
Following the previous CL, this removes more global variables on
Wasm.

PC_B is used mostly for intra-function jumps, and for a function
telling its callee where to start or resume. This usage can be
served by a parameter. The top level loop (wasm_pc_f_loop) uses
PC_B for resuming a function. This value is either set by gogo,
or loaded from the Go stack at function return. Instead of
loading PC_B at each function return, we could make gogo stores
PC_B at the same stack location, and let the top level loop do
the load. This way, we don't need to use global PC_B to
communicate with the top level loop, and we can replace global
PC_B with a parameter.

PC_F is similar. It is even more so in that the only reader is
the top level loop. Let the top level loop read it from the stack,
and we can get rid of PC_F entirely.

PC_F and PC_B are used less entensively as SP, so this CL has
smaller performance gain.

Running on Chrome 74.0.3729.108 on Linux/AMD64,

name                   old time/op    new time/op    delta
BinaryTree17              16.6s ± 0%     16.2s ± 1%   -2.59%  (p=0.016 n=4+5)
Fannkuch11                11.1s ± 1%     10.8s ± 0%   -2.65%  (p=0.008 n=5+5)
FmtFprintfEmpty           231ns ± 1%     217ns ± 0%   -6.06%  (p=0.008 n=5+5)
FmtFprintfString          407ns ± 3%     375ns ± 2%   -7.81%  (p=0.008 n=5+5)
FmtFprintfInt             466ns ± 2%     430ns ± 0%   -7.79%  (p=0.016 n=5+4)
FmtFprintfIntInt          719ns ± 2%     673ns ± 2%   -6.37%  (p=0.008 n=5+5)
FmtFprintfPrefixedInt     706ns ± 1%     676ns ± 3%   -4.31%  (p=0.008 n=5+5)
FmtFprintfFloat          1.01µs ± 1%    0.97µs ± 1%   -4.30%  (p=0.008 n=5+5)
FmtManyArgs              2.67µs ± 1%    2.51µs ± 1%   -5.95%  (p=0.008 n=5+5)
GobDecode                30.7ms ± 9%    31.3ms ±34%     ~     (p=0.222 n=5+5)
GobEncode                24.2ms ±23%    20.2ms ± 0%  -16.36%  (p=0.016 n=5+4)
Gzip                      852ms ± 0%     823ms ± 0%   -3.38%  (p=0.016 n=4+5)
Gunzip                    160ms ± 1%     151ms ± 1%   -5.37%  (p=0.008 n=5+5)
JSONEncode               35.7ms ± 1%    34.3ms ± 1%   -3.81%  (p=0.008 n=5+5)
JSONDecode                247ms ± 8%     254ms ± 7%     ~     (p=0.548 n=5+5)
Mandelbrot200            5.39ms ± 0%    5.41ms ± 0%   +0.42%  (p=0.008 n=5+5)
GoParse                  18.5ms ± 1%    18.3ms ± 2%     ~     (p=0.343 n=4+4)
RegexpMatchEasy0_32       424ns ± 2%     397ns ± 0%   -6.23%  (p=0.008 n=5+5)
RegexpMatchEasy0_1K      2.88µs ± 0%    2.86µs ± 1%     ~     (p=0.079 n=5+5)
RegexpMatchEasy1_32       395ns ± 2%     370ns ± 1%   -6.23%  (p=0.008 n=5+5)
RegexpMatchEasy1_1K      3.26µs ± 0%    3.19µs ± 1%   -2.06%  (p=0.008 n=5+5)
RegexpMatchMedium_32      564ns ± 1%     532ns ± 0%   -5.71%  (p=0.008 n=5+5)
RegexpMatchMedium_1K      146µs ± 2%     140µs ± 1%   -4.62%  (p=0.008 n=5+5)
RegexpMatchHard_32       8.47µs ± 1%    7.91µs ± 1%   -6.65%  (p=0.008 n=5+5)
RegexpMatchHard_1K        253µs ± 1%     236µs ± 2%   -6.66%  (p=0.008 n=5+5)
Revcomp                   1.78s ± 4%     1.76s ± 5%     ~     (p=1.000 n=5+5)
Template                  292ms ±29%     269ms ± 5%     ~     (p=0.690 n=5+5)
TimeParse                1.61µs ± 4%    1.54µs ± 1%   -4.42%  (p=0.008 n=5+5)
TimeFormat               1.66µs ± 3%    1.58µs ± 1%   -5.22%  (p=0.008 n=5+5)
[Geo mean]                232µs          221µs        -4.54%

name                   old speed      new speed      delta
GobDecode              25.0MB/s ± 8%  25.1MB/s ±27%     ~     (p=0.222 n=5+5)
GobEncode              32.8MB/s ±21%  38.0MB/s ± 0%  +15.84%  (p=0.016 n=5+4)
Gzip                   22.8MB/s ± 0%  23.6MB/s ± 0%   +3.49%  (p=0.016 n=4+5)
Gunzip                  121MB/s ± 1%   128MB/s ± 1%   +5.68%  (p=0.008 n=5+5)
JSONEncode             54.4MB/s ± 1%  56.5MB/s ± 1%   +3.97%  (p=0.008 n=5+5)
JSONDecode             7.88MB/s ± 8%  7.65MB/s ± 8%     ~     (p=0.548 n=5+5)
GoParse                3.07MB/s ± 8%  3.00MB/s ±22%     ~     (p=0.579 n=5+5)
RegexpMatchEasy0_32    75.6MB/s ± 2%  80.5MB/s ± 0%   +6.58%  (p=0.008 n=5+5)
RegexpMatchEasy0_1K     356MB/s ± 0%   358MB/s ± 1%     ~     (p=0.095 n=5+5)
RegexpMatchEasy1_32    81.1MB/s ± 2%  86.5MB/s ± 1%   +6.69%  (p=0.008 n=5+5)
RegexpMatchEasy1_1K     314MB/s ± 0%   320MB/s ± 0%   +2.10%  (p=0.008 n=5+5)
RegexpMatchMedium_32   1.77MB/s ± 1%  1.88MB/s ± 0%   +6.09%  (p=0.016 n=5+4)
RegexpMatchMedium_1K   6.99MB/s ± 2%  7.33MB/s ± 1%   +4.83%  (p=0.008 n=5+5)
RegexpMatchHard_32     3.78MB/s ± 1%  4.04MB/s ± 1%   +7.04%  (p=0.008 n=5+5)
RegexpMatchHard_1K     4.04MB/s ± 1%  4.33MB/s ± 2%   +7.17%  (p=0.008 n=5+5)
Revcomp                 143MB/s ± 4%   145MB/s ± 5%     ~     (p=1.000 n=5+5)
Template               6.77MB/s ±24%  7.22MB/s ± 5%     ~     (p=0.690 n=5+5)
[Geo mean]             24.4MB/s       25.4MB/s        +4.18%

Change-Id: Ib80716e62992aec28b2c4a96af280c278f83aa49
Reviewed-on: https://go-review.googlesource.com/c/go/+/173980
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
2019-05-24 17:41:56 +00:00
Michael Anthony Knyszek 7ed7669c0d runtime: ensure mheap lock stack growth invariant is maintained
Currently there's an invariant in the runtime wherein the heap lock
can only be acquired on the system stack, otherwise a self-deadlock
could occur if the stack grows while the lock is held.

This invariant is upheld and documented in a number of situations (e.g.
allocManual, freeManual) but there are other places where the invariant
is either not maintained at all which risks self-deadlock (e.g.
setGCPercent, gcResetMarkState, allocmcache) or is maintained but
undocumented (e.g. gcSweep, readGCStats_m).

This change adds go:systemstack to any function that acquires the heap
lock or adds a systemstack(func() { ... }) around the critical section,
where appropriate. It also documents the invariant on (*mheap).lock
directly and updates repetitive documentation to refer to that comment.

Fixes #32105.

Change-Id: I702b1290709c118b837389c78efde25c51a2cafb
Reviewed-on: https://go-review.googlesource.com/c/go/+/177857
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-24 15:34:57 +00:00
Russ Cox 06b0babf31 all: shorten some tests
Shorten some of the longest tests that run during all.bash.
Removes 7r 50u 21s from all.bash.

After this change, all.bash is under 5 minutes again on my laptop.

For #26473.

Change-Id: Ie0460aa935808d65460408feaed210fbaa1d5d79
Reviewed-on: https://go-review.googlesource.com/c/go/+/177559
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-05-22 12:54:00 +00:00
Keith Randall 6105e8b419 runtime: revert init order changes
First, remove the randomization of initialization order.

Then, revert to source code order instead of sorted package path order.

This restores the behavior that was in 1.12.

A larger change which will implement the suggestion in #31636 will
wait for 1.14. It's too complicated for 1.13 at this point (it has
tricky interactions with plugins).

Fixes #31636

Change-Id: I35b48e8cc21cf9f93c0973edd9193d2eac197628
Reviewed-on: https://go-review.googlesource.com/c/go/+/178297
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-05-22 11:07:00 +00:00
Keith Randall c77a9e0aa5 runtime: In Frames.Next, delay file/line lookup until just before return
That way we will never have to look up the file/line for the frame
that's next to be returned when the user stops calling Next.

For the benchmark from #32093:

name      old time/op  new time/op  delta
Helper-4   948ns ± 1%   836ns ± 3%  -11.89%  (p=0.000 n=9+9)

(#32093 was fixed with a more specific, and better, fix, but this
fix is much more general.)

Change-Id: I89e796f80c9706706d8d8b30eb14be3a8a442846
Reviewed-on: https://go-review.googlesource.com/c/go/+/178077
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-05-20 17:41:49 +00:00
Michael Anthony Knyszek 5a90306344 runtime: overhaul TestPhysicalMemoryUtilization
Currently, this test allocates many objects and relies on heap-growth
scavenging to happen unconditionally on heap-growth. However with the
new pacing system for the scavenging, this is no longer true and the
test is flaky.

So, this change overhauls TestPhysicalMemoryUtilization to check the
same aspect of the runtime, but in a much more robust way.

Firstly, it sets up a much more constrained scenario: only 5 objects are
allocated total with a maximum worst-case (i.e. the test fails) memory
footprint of about 16 MiB. The test is now aware that scavenging will
only happen if the heap growth causes us to push way past our scavenge
goal, which is based on the heap goal. So, it makes the holes in the
test much bigger and the actual retained allocations much smaller to
keep the heap goal at the heap's minimum size. It does this twice to
create exactly two unscavenged holes. Because the ratio between the size
of the "saved" objects and the "condemned" object is so small, two holes
are sufficient to create a consistent test.

Then, the test allocates one enormous object (the size of the 4 other
objects allocated, combined) with the intent that heap-growth scavenging
should kick in and scavenge the holes. The heap goal will rise after
this object is allocated, so it's very important we do all the
scavenging in a single allocation that exceeds the heap goal because
otherwise the rising heap goal could foil our test.

Finally, we check memory use relative to HeapAlloc as before. Since the
runtime should scavenge the entirety of the remaining holes,
theoretically there should be no more free and unscavenged memory.
However due to other allocations that may happen during the test we may
still see unscavenged memory, so we need to have some threshold. We keep
the current 10% threshold which, while arbitrary, is very conservative
and should easily account for any other allocations the test makes.

Before, we also had to ensure the allocations we were making looked
large relative to the size of a heap arena since newly-mapped memory was
considered unscavenged, and so that could significantly skew the test.
However, thanks to the fix for #32012 we were able to reduce memory use
to 16 MiB in the worst case.

Fixes #32010.

Change-Id: Ia38130481e292f581da7fa3289c98c99dc5394ed
Reviewed-on: https://go-review.googlesource.com/c/go/+/177237
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-20 16:26:57 +00:00
Joel Sing ee551846fa runtime: correct netbsd/amd64 assembly for timespec handling
A timespec on netbsd/amd64 is int64/int64, not int64/int32.
This bug appears to have been introduced in 7777bac6e4.

Spotted by Cherry Zhang while reviewing https://go-review.googlesource.com/c/go/+/177120.

Change-Id: I163c55d926965defd981bdbfd2511de7d9d4c542
Reviewed-on: https://go-review.googlesource.com/c/go/+/177637
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
2019-05-17 14:32:34 +00:00
Joel Sing 37133b5d63 runtime: fix netbsd/arm64 assembly
Fix various bugs in the netbsd/arm64 runtime assembly.

Updates #30824.

Change-Id: I5ca10926ab663a8ff4df9973530e645e2469c1aa
Reviewed-on: https://go-review.googlesource.com/c/go/+/177120
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-05-17 14:30:55 +00:00
Joey 29f14f058d runtime: remove redundant "//"
Change-Id: I44af6cd8baa8fcd2a666429467fae4bed5f21fa0
GitHub-Last-Rev: d0c9722f08
GitHub-Pull-Request: golang/go#32052
Reviewed-on: https://go-review.googlesource.com/c/go/+/177277
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
2019-05-17 04:27:18 +00:00
Michael Anthony Knyszek 4e7bef84c1 runtime: mark newly-mapped memory as scavenged
On most platforms newly-mapped memory is untouched, meaning the pages
backing the region haven't been faulted in yet. However, we mark this
memory as unscavenged which means the background scavenger
aggressively "returns" this memory to the OS if the heap is small.

The only platform where newly-mapped memory is actually unscavenged (and
counts toward the application's RSS) is on Windows, since
(*mheap).sysAlloc commits the reservation. Instead of making a special
case for Windows, I change the requirements a bit for a sysReserve'd
region. It must now be both sysMap'd and sysUsed'd, with sysMap being a
no-op on Windows. Comments about memory allocation have been updated to
include a more up-to-date mental model of which states a region of memory
may be in (at a very low level) and how to transition between these
states.

Now this means we can correctly mark newly-mapped heap memory as
scavenged on every platform, reducing the load on the background
scavenger early on in the application for small heaps. As a result,
heap-growth scavenging is no longer necessary, since any actual RSS
growth will be accounted for on the allocation codepath.

Finally, this change also cleans up grow a little bit to avoid
pretending that it's freeing an in-use span and just does the necessary
operations directly.

Fixes #32012.
Fixes #31966.
Updates #26473.

Change-Id: Ie06061eb638162e0560cdeb0b8993d94cfb4d290
Reviewed-on: https://go-review.googlesource.com/c/go/+/177097
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-16 22:00:47 +00:00
Russ Cox 018d9b42a7 runtime: disable some tests in -quick mode
Speeds up the "go test runtime -cpu=1,2,4 -short -quick" phase of all.bash.

For #26473.

Change-Id: I090f5a5aa754462b3253a2156dc31fa67ce7af2a
Reviewed-on: https://go-review.googlesource.com/c/go/+/177399
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-16 03:25:03 +00:00
Russ Cox 639ac76d45 runtime: fix 'go vet -race runtime'
This updates the Go function declarations to match race_amd64.s.

Change-Id: I2b541a6b335ce732f4c31652aa615240ce7bb1c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/177397
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-16 03:24:54 +00:00
Clément Chigot 1956b28ae3 runtime: call atomic.Storeuintptr in noteclear on AIX
The memory might not be synchronized in a thread being woken up after a
semasleep. Using atomic instructions in noteclear function will force
this synchronisation.

Fixes #30189

Change-Id: If7432f29b2a1a56288231822db52f3f8d1d6dbfe
Reviewed-on: https://go-review.googlesource.com/c/go/+/163624
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-05-14 15:01:49 +00:00
Tamir Duberstein 9c86eae384 runtime: resolve latent TODOs
These were added in https://go-review.googlesource.com/1224; according
to austin@google.com these annotations are not valuable - resolving by
removing the TODOs.

Change-Id: Icf3f21bc385cac9673ba29f0154680e970cf91f2
Reviewed-on: https://go-review.googlesource.com/c/go/+/176899
Reviewed-by: Austin Clements <austin@google.com>
2019-05-13 19:33:29 +00:00
Tamir Duberstein 7a43f8a5fb runtime: resolve latent function type TODO
This was left over from the C->Go transition.

Change-Id: I52494af3d49a388dc45b57210ba68292ae01cf84
Reviewed-on: https://go-review.googlesource.com/c/go/+/176897
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-13 18:40:10 +00:00
Russ Cox ef4666ecce runtime: fix windows-amd64-2012 build
I forgot that in Go assembly, x+16(SP) is not the same as 16(SP).
The former is the virtual stack pointer (one word below FP on x86)
while the latter is the actual stack pointer.

Change-Id: Ibb7012bb97261949f5e1a0dc70869d9a6f50aa99
Reviewed-on: https://go-review.googlesource.com/c/go/+/176557
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-05-10 16:16:30 +00:00
Russ Cox 40657c282d runtime: fix s390x build
The new prototypes of duffzero and duffcopy must be
accompanied by functions. Otherwise buildmode=shared
(in particular, misc/cgo/testshared) has missing symbols.

The right fix, of course, is to implement these on s390x.

For #31916.

Change-Id: I3efff5e3011956341e1b26223a4847a8a91a0453
Reviewed-on: https://go-review.googlesource.com/c/go/+/176397
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-09 23:41:02 +00:00
Russ Cox a4f5c9c40d runtime: fix vet complaints for js/wasm
Change-Id: Ifc8a731a2efd94fdc4fc6f26ca6e16f0c0292211
Reviewed-on: https://go-review.googlesource.com/c/go/+/176178
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 21:13:56 +00:00
Russ Cox 56c1cf315d runtime: fix vet complaints for all nacl
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for nacl/*,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I6adb4a7b0c2b03d901fba37f9c05e74e5b7b6691
Reviewed-on: https://go-review.googlesource.com/c/go/+/176107
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-09 21:13:46 +00:00
Russ Cox 13723d44a0 runtime, crypto/x509: fix vet complaints for all windows
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for windows/*,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: If37ab2b3f6fca4696b8a6afb2ef11ba6c4fb42e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/176106
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 21:13:39 +00:00
Russ Cox 924c161de4 runtime: fix vet complaints for all freebsd, netbsd, openbsd
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOSes,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I63c4805bdd44b301072da66c77086940e2a2765e
Reviewed-on: https://go-review.googlesource.com/c/go/+/176105
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-09 21:13:26 +00:00
Russ Cox 60f67631a6 runtime: fix vet complaints for solaris/amd64, illumos/amd64
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOS/GOARCHes,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: Ic64f7f4034695dd4c32c9b7f258960faf3742a83
Reviewed-on: https://go-review.googlesource.com/c/go/+/176103
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-09 21:13:23 +00:00
Russ Cox 49f62af790 runtime: fix vet complaints for linux/arm64, linux/mips*, linux/ppc64*, linux/s390x
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOS/GOARCHes,
except for an unresolved complaint on mips/mipsle that is a bug in vet,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I6ef7e982a2fdbbfbc22cee876ca37ac54d8109e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/176102
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 21:13:22 +00:00
Russ Cox 1ea76443ba runtime: fix vet complaints for linux/arm
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "GOOS=linux GOARCH=arm go vet -unsafeptr=false runtime" happy,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: Ifae75b832320b5356ac8773cf85055bfb2bd7214
Reviewed-on: https://go-review.googlesource.com/c/go/+/176101
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-09 21:13:21 +00:00
Russ Cox fe67ce2efb runtime: fix vet complaints for linux/amd64
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "GOOS=linux GOARCH=amd64 go vet -unsafeptr=false runtime" happy,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I4ca1acb02f4666b102d25fcc55fac96b8f80379a
Reviewed-on: https://go-review.googlesource.com/c/go/+/176100
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 21:13:19 +00:00
Russ Cox 6ed2ec4aa5 runtime: fix vet complaints for linux/386
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "GOOS=linux GOARCH=386 go vet -unsafeptr=false runtime" happy,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I3e5586a7ff6e359357350d0602c2259493280ded
Reviewed-on: https://go-review.googlesource.com/c/go/+/176099
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 21:13:18 +00:00
Michael Anthony Knyszek cd03664f82 runtime: fix js/wasm lock implementation
Trybots started failing on js/wasm after golang.org/cl/175797 landed,
but it seemed completely unrelated. It would fail very consistently on
the heapsampling.go test.

Digging deeper it was very difficult to ascertain what was going wrong,
but clearly m.locks for some m was non-zero when calling into the
scheduler.

The failure comes from the fact that lock calls into gosched, but it's
unclear how exactly we got there in the first place; there should be no
preemption in this single-threaded context.

Furthermore, lock shouldn't be calling gosched_m at all because in a
single-threaded context, the thread shouldn't be preempted until it
actually unlocks.

But, digging further it turns out the implementation in lock_js.go never
incremented or decremented m.locks. This is definitely wrong because
many parts of the runtime depend on that value being set correctly.

So, this change removes the loop which calls into gosched_m (which
should be unnecessary) and increments and decrements m.locks
appropriately. This appears to fix the aforementioned failure.

Change-Id: Id214c0762c3fb2b405ff55543d7e2a78c17443c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/176297
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-05-09 20:22:27 +00:00
Michael Anthony Knyszek ff70494b75 runtime: split spans when scavenging if it's more than we need
This change makes it so that during scavenging we split spans when the
span we have next for scavenging is larger than the amount of work we
have left to do.

The purpose of this change is to improve the worst-case behavior of the
scavenger: currently, if the scavenger only has a little bit of work to
do but sees a very large free span, it will scavenge the whole thing,
spending a lot of time to get way ahead of the scavenge pacing for no
reason.

With this change the scavenger should follow the pacing more closely,
but may still over-scavenge by up to a physical huge page since the
splitting behavior avoids breaking up huge pages in free spans.

This change is also the culmination of the scavenging improvements, so
we also include benchmark results for this series (starting from
"runtime: merge all treaps into one implementation" until this patch).

This patch stack results in average and peak RSS reductions (up to 11%
and 7% respectively) for some benchmarks, with mostly minimal
performance degredation (3-4% for some benchmarks, ~0% geomean). Each of
these benchmarks was executed with GODEBUG=madvdontneed=1 on Linux; the
performance degredation is even smaller when MADV_FREE may be used, but
the impact on RSS is much harder to measure. Applications that generally
maintain a steady heap size for the most part show no change in
application performance.

These benchmarks are taken from an experimental benchmarking suite
representing a variety of open-source Go packages, the raw results may
be found here:

https://perf.golang.org/search?q=upload:20190509.1

For #30333.

Change-Id: I618a48534d2d6ce5f656bb66825e3c383ab1ffba
Reviewed-on: https://go-review.googlesource.com/c/go/+/175797
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 16:23:09 +00:00
Michael Anthony Knyszek fe67ea32bf runtime: add background scavenger
This change adds a background scavenging goroutine whose pacing is
determined when the heap goal changes. The scavenger is paced to use
at most 1% of the mutator's time for most systems. Furthermore, the
scavenger's pacing is computed based on the estimated number of
scavengable huge pages to take advantage of optimizations provided by
the OS.

The purpose of this scavenger is to deal with a shrinking heap: if the
heap goal is falling over time, the scavenger should kick in and start
returning free pages from the heap to the OS.

Also, now that we have a pacing system, the credit system used by
scavengeLocked has become redundant. Replace it with a mechanism which
only scavenges on the allocation path if it makes sense to do so with
respect to the new pacing system.

Fixes #30333.

Change-Id: I6203f8dc84affb26c3ab04528889dd9663530edc
Reviewed-on: https://go-review.googlesource.com/c/go/+/142960
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 16:21:43 +00:00
Michael Anthony Knyszek eaa1c87b00 runtime: remove periodic scavenging
This change removes the periodic scavenger which goes over every span
in the heap and scavenges it if it hasn't been used for 5 minutes. It
should no longer be necessary if we have background scavenging
(follow-up).

For #30333.

Change-Id: Ic3a1a4e85409dc25719ba4593a3b60273a4c71e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/143157
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 16:20:52 +00:00
Russ Cox b6f59cbc80 cmd/vet/all: update whitelist for vet fixes
The vetall builder runs vet straight out of golang.org/x/tools,
so submiting CL 176097 in that repo will break the builder
by making all these whitelist entries stale.
Submiting this CL will fix it, by removing them.

The addition of the gcWriteBarrier declaration in runtime/stubs.go
is necessary because the diagnostic is no longer emitted on arm,
so it must be removed from all.txt. Adding it to runtime is better
than adding it to every-other-goarch.txt.

For #31916.

Change-Id: I432f6049cd3ee5a467add5066c440be8616d9d54
Reviewed-on: https://go-review.googlesource.com/c/go/+/176177
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-09 15:32:36 +00:00
Lorenz Nickel bef15341e1 doc: fixed some links
Change-Id: I8563a20a4ba43cee7d4b73377c405a6ff12636e5
GitHub-Last-Rev: 0dae408845
GitHub-Pull-Request: golang/go#31914
Reviewed-on: https://go-review.googlesource.com/c/go/+/176017
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-08 16:38:55 +00:00
Michael Anthony Knyszek 31c4e09915 runtime: ensure free and unscavenged spans may be backed by huge pages
This change adds a new sysHugePage function to provide the equivalent of
Linux's madvise(MADV_HUGEPAGE) support to the runtime. It then uses
sysHugePage to mark a newly-coalesced free span as backable by huge
pages to make the freeHugePages approximation a bit more accurate.

The problem being solved here is that if a large free span is composed
of many small spans which were coalesced together, then there's a chance
that they have had madvise(MADV_NOHUGEPAGE) called on them at some point,
which makes freeHugePages less accurate.

For #30333.

Change-Id: Idd4b02567619fc8d45647d9abd18da42f96f0522
Reviewed-on: https://go-review.googlesource.com/c/go/+/173338
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-06 21:15:01 +00:00
Michael Anthony Knyszek 5c15ed64de runtime: split spans during allocation without treap removal
Now that the treap is first-fit, we can make a nice optimization.
Mainly, since we know that span splitting doesn't modify the relative
position of a span in a treap, we can actually modify a span in-place
on the treap. The only caveat is that we need to update the relevant
metadata.

To enable this optimization, this change introduces a mutate method on
the iterator which takes a callback that is passed the iterator's span.
The method records some properties of the span before it calls into the
callback and then uses those records to see what changed and update
treap metadata appropriately.

Change-Id: I74f7d2ee172800828434ba0194d3d78d3942acf2
Reviewed-on: https://go-review.googlesource.com/c/go/+/174879
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-06 21:14:52 +00:00
Michael Anthony Knyszek f4a5ae5594 runtime: track the number of free unscavenged huge pages
This change tracks the number of potential free and unscavenged huge
pages which will be used to inform the rate at which scavenging should
occur.

For #30333.

Change-Id: I47663e5ffb64cac44ffa10db158486783f707479
Reviewed-on: https://go-review.googlesource.com/c/go/+/170860
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-06 20:59:20 +00:00
Michael Anthony Knyszek a62b5723be runtime: scavenge huge spans first
This change adds two new treap iteration types: one for large
unscavenged spans (contain at least one huge page) and one for small
unscavenged spans. This allows us to scavenge the huge spans first by
first iterating over the large ones, then the small ones.

Also, since we now depend on physHugePageSize being a power of two,
ensure that that's the case when it's retrieved from the OS.

For #30333.

Change-Id: I51662740205ad5e4905404a0856f5f2b2d2a5680
Reviewed-on: https://go-review.googlesource.com/c/go/+/174399
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-06 20:57:39 +00:00
Michael Anthony Knyszek fa8470a8cd runtime: make treap iteration more efficient
This change introduces a treapIterFilter type which represents the
power set of states described by a treapIterType.

This change then adds a treapIterFilter field to each treap node
indicating the types of spans that live in that subtree. The field is
maintained via the same mechanism used to maintain maxPages. This allows
pred, succ, start, and end to be judicious about which subtrees it will
visit, ensuring that iteration avoids traversing irrelevant territory.

Without this change, repeated scavenging attempts can end up being N^2
as the scavenger walks over what it already scavenged before finding new
spans available for scavenging.

Finally, this change also only scavenges a span once it is removed from
the treap. There was always an invariant that spans owned by the treap
may not be mutated in-place, but with this change violating that
invariant can cause issues with scavenging.

For #30333.

Change-Id: I8040b997e21c94a8d3d9c8c6accfe23cebe0c3d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/174878
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-06 20:50:16 +00:00
Michael Anthony Knyszek 9baa4301cf runtime: merge all treaps into one implementation
This change modifies the treap implementation to support holding all
spans in a single treap, instead of keeping them all in separate treaps.

This improves ergonomics for nearly all treap-related callsites.
With that said, iteration is now more expensive, but it never occurs on
the fast path, only on scavenging-related paths.

This change opens up the opportunity for further optimizations, such as
splitting spans without treap removal (taking treap removal off the span
allocator's critical path) as well as improvements to treap iteration
(building linked lists for each iteration type and managing them on
insert/removal, since those operations should be less frequent).

For #30333.

Change-Id: I3dac97afd3682a37fda09ae8656a770e1369d0a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/174398
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-06 20:19:44 +00:00
Iskander Sharipov 12e63226b9 all: remove commented-out print statements
Those print statements are not a good debug helpers
and only clutter the code.

Change-Id: Ifbf450a04e6fa538af68e6352c016728edb4119a
Reviewed-on: https://go-review.googlesource.com/c/go/+/160537
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2019-05-05 08:09:30 +00:00
Austin Clements 4a4e05b0b1 cmd/compile,runtime/internal/atomic: add Load8
Change-Id: Id52a5730cf9207ee7ccebac4ef12791dc5720e7c
Reviewed-on: https://go-review.googlesource.com/c/go/+/172283
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2019-05-03 19:25:37 +00:00
Michael Anthony Knyszek 7fcba81549 runtime: remove sys.HugePageSize
sys.HugePageSize was superceded in the last commit by physHugePageSize
which is determined dynamically by querying the operating system.

For #30333.

Change-Id: I827bfca8bdb347e989cead31564a8fffe56c66ff
Reviewed-on: https://go-review.googlesource.com/c/go/+/173757
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-03 18:42:04 +00:00
Michael Anthony Knyszek 1033065ee3 runtime: add physHugePageSize
This change adds the global physHugePageSize which is initialized in
osinit(). physHugePageSize contains the system's transparent huge page
(or superpage) size in bytes.

For #30333.

Change-Id: I2f0198c40729dbbe6e6f2676cef1d57dd107562c
Reviewed-on: https://go-review.googlesource.com/c/go/+/170858
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-03 18:41:45 +00:00
David Chase e56c73f17b runtime: look for idle p to run current goroutine when switching to GC or traceReader
This repairs one of the several causes of pauses uncovered
by a GC microbenchmark.  A pause can occur when a goroutine's
quantum expires "at the same time" a GC is needed.  The
current M switches to running a GC worker, which means that
the amount of available work has expanded by one.  The GC
worker, however, does not call ready, and does not itself
conditionally wake a P (a "normal" thread would do this).

This is also true if M switches to a traceReader.

This is problem 4 in this list:
https://github.com/golang/go/issues/27732#issuecomment-423301252

Updates #27732.

Change-Id: I6905365cac8504cde6faab2420f4421536551f0b
Reviewed-on: https://go-review.googlesource.com/c/go/+/146817
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-01 16:10:05 +00:00
Michael Anthony Knyszek 40036a99a0 runtime: change the span allocation policy to first-fit
This change modifies the treap implementation to be address-ordered
instead of size-ordered, and further augments it so it may be used for
allocation. It then modifies the find method to implement a first-fit
allocation policy.

This change to the treap implementation consequently makes it so that
spans are scavenged in highest-address-first order without any
additional changes to the scavenging code. Because the treap itself is
now address ordered, and the scavenging code iterates over it in
reverse, the highest address is now chosen instead of the largest span.

This change also renames the now wrongly-named "scavengeLargest" method
on mheap to just "scavengeLocked" and also fixes up logic in that method
which made assumptions about size.

For #30333.

Change-Id: I94b6f3209211cc1bfdc8cdaea04152a232cfbbb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/164101
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-05-01 14:50:40 +00:00
Josh Bleecher Snyder 73cb9a1cb3 all: refer to map elements as elements instead of values
The spec carefully and consistently uses "key" and "element"
as map terminology. The implementation, not so much.

This change attempts to make the implementation consistently
hew to the spec's terminology. Beyond consistency, this has
the advantage of avoid some confusion and naming collisions,
since v and value are very generic and commonly used terms.

I believe that I found all everything, but there are a lot of
non-obvious places for these to hide, and grepping for them is hard.
Hopefully this change changes enough of them that we will start using
elem going forward. Any remaining hidden cases can be removed ad hoc
as they are discovered.

The only externally-facing part of this change is in package reflect,
where there is a minor doc change and a function parameter name change.

Updates #27167

Change-Id: I2f2d78f16c360dc39007b9966d5c2046a29d3701
Reviewed-on: https://go-review.googlesource.com/c/go/+/174523
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-30 18:18:12 +00:00
Keith Randall 1fd1408203 runtime: fix data sizes for res_search results
The return values are 32 bit, not 64 bit.

I don't think this would be the cause of any problems, but
it can't hurt to fix it.

Change-Id: Icdd50606360ab9d74070271f9d1721d5fe640bc7
Reviewed-on: https://go-review.googlesource.com/c/go/+/174518
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-04-30 17:45:16 +00:00
Joshua M. Clulow f686a2890b all: add new GOOS=illumos, split out of GOOS=solaris
Like GOOS=android which implies the "linux" build tag, GOOS=illumos
implies the "solaris" build tag. This lets the existing ecosystem of
packages still work on illumos, but still permits packages to start
differentiating between solaris and illumos.

Fixes #20603

Change-Id: I8f4eabf1a66060538dca15d7658c1fbc6c826622
Reviewed-on: https://go-review.googlesource.com/c/go/+/174457
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-04-30 16:59:13 +00:00
Elias Naur 9f12e2e04b runtime: implement pthread functions for darwin/arm64
They were not needed when Go only produced binaries with cgo suppport.
Now that Go is about to run self-hosted on iOS we do need these.

Updates #31722

Change-Id: If233aa2b31edc7b1c2dcac68974f9fba0604f9a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/174300
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2019-04-30 16:43:59 +00:00
Richard Musiol c2d9eea1f1 runtime: do not use heap arena hints on wasm
The address space of WebAssembly's linear memory is contiguous, so
requesting specific addresses is not supported. Do not use heap arena
hints so we do not have unused memory ranges.

This fixes go1 benchmarks on wasm which ran out of memory since
https://golang.org/cl/170950.

Change-Id: I70115b18dbe43abe16dd5f57996343d97bf94760
Reviewed-on: https://go-review.googlesource.com/c/go/+/174203
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-04-30 08:25:33 +00:00