heap_live is updated atomically without locking, so we should also use
atomic loads to read it. Fix the reads of heap_live that happen
outside of STW to be atomic.
Change-Id: Idca9451c348168c2a792a9499af349833a3c333f
Reviewed-on: https://go-review.googlesource.com/41371
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
On 32-bit architectures (or if we fail to map a 64-bit-style arena),
we try to map the heap arena just above the end of the process image.
While we can accept any address, using lower addresses is preferable
because lower addresses cause us to map less of the heap bitmap.
However, if a program is linked against C code that has global
constructors, those constructors may call brk/sbrk to allocate memory
(e.g., many C malloc implementations do this for small allocations).
The brk also starts just above the process image, so this may adjust
the brk past the beginning of where we want to put the heap arena. In
this case, the kernel will pick a different address for the arena and
it will usually be very high (at least, as these things go in a 32-bit
address space).
Fix this by consulting the current value of the brk and using this in
addition to the end of the process image to compute the initial arena
placement.
This is implemented only on Linux currently, since we have no evidence
that it's an issue on any other OSes.
Fixes#19831.
Change-Id: Id64b45d08d8c91e4f50d92d0339146250b04f2f8
Reviewed-on: https://go-review.googlesource.com/39810
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TestBreakpoint expects to see "runtime.Breakpoint()" in the stack trace.
If runtime.Breakpoint() is inlined, then the stack trace prints
"runtime.Breakpoint(...)" since the runtime does not have information
about arguments (or lack thereof) to inlined functions. This change
makes the test independent of inlining by looking for the string
"runtime.Breakpoint(". Now TestBreakpoint passes with -l=4.
Change-Id: Ia044a8e8a4de2337cb2b393d6fa78c73a2f25926
Reviewed-on: https://go-review.googlesource.com/40997
Run-TryBot: David Lazar <lazard@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TestBlockProfile matches samples against a regexp that accepts "," in
profile PCs. I suspect this was just a syntax mistake. Remove "," from
the character class.
Change-Id: Idcfc20ed6900075abae08597ba71db559e89b37b
Reviewed-on: https://go-review.googlesource.com/41111
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Peter Weinberger <pjw@google.com>
TestBlockProfile currently requires exactly five PCs in each sample.
With more aggressive inlining there may be fewer, so change this test
to use the same pattern as TestMutexProfile, which accepts one or more
PCs. With this change, this test passes when compiled with -l=4.
Change-Id: I1421a6d56c96b77111bdc671d88723a222672fd6
Reviewed-on: https://go-review.googlesource.com/41110
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Lazar <lazard@golang.org>
CL 40876 changed ExampleFrames so that the output
was stable with and without mid-stack inlining.
However, that change lost some of the
pedagogical and copy/paste value of the example.
It was unclear why both more and i were being tracked,
and whether the 5 in i < 5 is related to len(pc),
and if so, why and how.
This CL rewrites the example with lots more comments,
and such that the core structure more closely matches
normal usage, and such that it is obvious
which lines of code should be deleted when copying.
As a bonus, it also now illustrates Frame.File.
Change-Id: Iab73541dd096657ddf79c5795337e8b596d89740
Reviewed-on: https://go-review.googlesource.com/41136
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The period recorded in CPU profiles is in nanoseconds, but was being
computed incorrectly as hz * 1000. As a result, many absolute times
displayed by pprof were incorrect.
Fix this by computing the period correctly.
Change-Id: I6fadd6d8ad3e57f31e8cc7a25a24fcaec510d8d4
Reviewed-on: https://go-review.googlesource.com/40995
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Instead of populating the aux symbol
of CALLudiv during rewrite rules,
populate it during genssa.
This simplifies the rewrite rules.
It also removes all remaining calls
to ctxt.Lookup from any rewrite rules.
This is a first step towards removing
ctxt from ssa.Cache entirely,
and also a first step towards converting
the obj.LSym.Version field into a boolean.
It should also speed up compilation.
Also, move func udiv into package runtime.
That's where it is anyway,
and it lets udiv look and act like the rest of
the runtime support functions.
Change-Id: I41462a632c14fdc41f61b08049ec13cd80a87bfe
Reviewed-on: https://go-review.googlesource.com/41191
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Returns at the end of func bodies where the funcs have no return values
are pointless.
Change-Id: I0da5ea78671503e41a9f56dd770df8c919310ce5
Reviewed-on: https://go-review.googlesource.com/41093
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This extends the GCSweepDone event with counts of swept and reclaimed
bytes. These are useful for understanding the duration and
effectiveness of sweep events.
Change-Id: I3c97a4f0f3aad3adbd188adb264859775f54e2df
Reviewed-on: https://go-review.googlesource.com/40811
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Currently, each individual span sweep emits a span to the trace. But
sweeps are generally done in loops until some condition is satisfied,
so this tracing is lower-level than anyone really wants any hides the
fact that no other work is being accomplished between adjacent sweep
events. This is also high overhead: enabling tracing significantly
impacts sweep latency.
Replace this with instead tracing around the sweep loops used for
allocation. This is slightly tricky because sweep loops don't
generally know if any sweeping will happen in them. Hence, we make the
tracing lazy by recording in the P that we would like to start tracing
the sweep *if* one happens, and then only closing the sweep event if
we started it.
This does mean we don't get tracing on every sweep path, which are
legion. However, we get much more informative tracing on the paths
that block allocation, which are the paths that matter.
Change-Id: I73e14fbb250acb0c9d92e3648bddaa5e7d7e271c
Reviewed-on: https://go-review.googlesource.com/40810
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Changes the text to match GOOS which appends 'and so on' at the
end to avoid restricting the set of possible values.
Change-Id: I54bcde71334202cf701662cdc2582c974ba8bf53
Reviewed-on: https://go-review.googlesource.com/41074
Reviewed-by: Ian Lance Taylor <iant@golang.org>
When allocating a non-small array of buckets for a map,
also preallocate some overflow buckets.
The estimate of the number of overflow buckets
is based on a simulation of putting mid=(low+high)/2 elements
into a map, where low is the minimum number of elements
needed to reach this value of b (according to overLoadFactor),
and high is the maximum number of elements possible
to put in this value of b (according to overLoadFactor).
This estimate is surprisingly reliable and accurate.
The number of overflow buckets needed is quadratic,
for a fixed value of b.
Using this mid estimate means that we will overallocate a few
too many overflow buckets when the actual number of elements is near low,
and underallocate significantly too few overflow buckets
when the actual number of elements is near high.
The mechanism introduced in this CL can be re-used for
other overflow bucket optimizations.
For example, given an initial size hint,
we could estimate quite precisely the number of overflow buckets.
This is #19931.
We could also change from "non-nil means end-of-list"
to "pointer-to-hmap.buckets means end-of-list",
and then create a linked list of reusable overflow buckets
when they are freed by map growth.
That is #19992.
We could also use a similar mechanism to do bulk allocation
of overflow buckets.
All these uses can co-exist with only the one additional pointer
in mapextra, given a little care.
name old time/op new time/op delta
MapPopulate/1-8 60.1ns ± 2% 60.3ns ± 2% ~ (p=0.278 n=19+20)
MapPopulate/10-8 577ns ± 1% 578ns ± 1% ~ (p=0.140 n=20+20)
MapPopulate/100-8 8.06µs ± 1% 8.19µs ± 1% +1.67% (p=0.000 n=20+20)
MapPopulate/1000-8 104µs ± 1% 104µs ± 1% ~ (p=0.317 n=20+20)
MapPopulate/10000-8 891µs ± 1% 888µs ± 1% ~ (p=0.101 n=19+20)
MapPopulate/100000-8 8.61ms ± 1% 8.58ms ± 0% -0.34% (p=0.009 n=20+17)
name old alloc/op new alloc/op delta
MapPopulate/1-8 0.00B 0.00B ~ (all equal)
MapPopulate/10-8 179B ± 0% 179B ± 0% ~ (all equal)
MapPopulate/100-8 3.33kB ± 0% 3.38kB ± 0% +1.48% (p=0.000 n=20+16)
MapPopulate/1000-8 55.5kB ± 0% 53.4kB ± 0% -3.84% (p=0.000 n=19+20)
MapPopulate/10000-8 432kB ± 0% 428kB ± 0% -1.06% (p=0.000 n=19+20)
MapPopulate/100000-8 3.65MB ± 0% 3.62MB ± 0% -0.70% (p=0.000 n=20+20)
name old allocs/op new allocs/op delta
MapPopulate/1-8 0.00 0.00 ~ (all equal)
MapPopulate/10-8 1.00 ± 0% 1.00 ± 0% ~ (all equal)
MapPopulate/100-8 18.0 ± 0% 17.0 ± 0% -5.56% (p=0.000 n=20+20)
MapPopulate/1000-8 96.0 ± 0% 72.6 ± 1% -24.38% (p=0.000 n=20+20)
MapPopulate/10000-8 625 ± 0% 319 ± 0% -48.86% (p=0.000 n=20+20)
MapPopulate/100000-8 6.23k ± 0% 4.00k ± 0% -35.79% (p=0.000 n=20+20)
Change-Id: I01f41cb1374bdb99ccedbc00d04fb9ae43daa204
Reviewed-on: https://go-review.googlesource.com/40979
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Any change to how we allocate overflow buckets
will require some extra hmap storage,
but we don't want hmap to grow,
particular as small maps usually don't need overflow buckets.
This CL converts the existing hmap overflow field,
which is usually used for pointer-free maps,
into a generic extra field.
This extra field can be used to hold data that is optional.
If it is valuable enough to do have special
handling of overflow buckets, which are medium-sized,
it is valuable enough to pay an extra alloc and two extra words for.
Adding fields to extra would entail adding overhead to pointer-free maps;
any mapextra fields added would need to be weighed against that.
This CL is just rearrangement, though.
Updates #19931
Updates #19992
Change-Id: If8537a206905b9d4dc6cd9d886184ece671b3f80
Reviewed-on: https://go-review.googlesource.com/40976
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This simplifies the code, as well as providing
a single place to modify to change the
allocation of new overflow buckets.
Updates #19931
Updates #19992
Change-Id: I77070619f5c8fe449bbc35278278bca5eda780f2
Reviewed-on: https://go-review.googlesource.com/40975
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Only the noinline pragma on testCallerFoo is needed to pass the test,
but the second pragma makes the test robust to future changes to the
inliner.
Change-Id: I80b384380c598f52e0382f53b59bb47ff196363d
Reviewed-on: https://go-review.googlesource.com/40877
Run-TryBot: David Lazar <lazard@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Otherwise, with -l=4, runtime.Callers gets inlined and the example
prints too many frames. Now the example passes with -l=4.
Change-Id: I9e420af9371724ac3ec89efafd76a658cf82bb4a
Reviewed-on: https://go-review.googlesource.com/40876
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This rewrites runtime.Caller in terms of stackExpander, which already
handles inlined frames and partially skipped frames. This also has the
effect of making runtime.Caller understand cgo frames if there is a cgo
symbolizer.
Updates #19348.
Change-Id: Icdf4df921aab5aa394d4d92e3becc4dd169c9a6e
Reviewed-on: https://go-review.googlesource.com/40270
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The Frames API forces the PC slice to escape to the heap because it
stores it in the Frames object. However, we'd like to use this API for
call stack expansion internally in the runtime in places where it
would be very good to avoid heap allocation.
This commit makes this possible by pulling the bulk of the Frames
implementation into an internal frameExpander API. The key difference
between these APIs is that the frameExpander does not hold the PC
slice; instead, the caller is responsible for threading the PC slice
through the frameExpander API calls. This makes it possible to keep
the PC slice on the stack. The Frames API then becomes a thin shim
around the frameExpander that keeps the PC slice in the Frames object.
Change-Id: If6b2d0b9132a2a905a0cf5deced9feddce76fc0e
Reviewed-on: https://go-review.googlesource.com/40610
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Lazar <lazard@golang.org>
While debugging a recent regression it was discovered that
the assembler for ppc64x was not always generating the correct
instruction for DS form loads and stores. When an instruction
is DS form then the offset must be a multiple of 4, and if it
isn't then bits outside the offset field were being incorrectly
set resulting in unexpected and incorrect instructions.
This change adds a check to determine when the opcode is DS form
and then verifies that the offset is a multiple of 4 before
generating the instruction, otherwise logs an error.
This also changes a few asm files that were using unaligned offsets
for DS form loads and stores. In the runtime package these were
instructions intended to cause a crash so using aligned or unaligned
offsets doesn't change that behavior.
Change-Id: Ie3a7e1e65dcc9933b54de7a46a054da8459cb56f
Reviewed-on: https://go-review.googlesource.com/40476
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Now the runtime/trace tests pass with -l=4.
This also gets rid of the frames cache for multiple reasons:
1) The frames cache was used to avoid repeated calls to funcname and
funcline. Now these calls happen inside the CallersFrames iterator.
2) Maintaining a frames cache is harder: map[uintptr]traceFrame
doesn't work since each PC can map to multiple traceFrames.
3) It's not clear that the cache is important.
Change-Id: I2914ac0b3ba08e39b60149d99a98f9f532b35bbb
Reviewed-on: https://go-review.googlesource.com/40591
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This extends the sweeper to free workbufs back to the heap between GC
cycles, allowing this memory to be reused for GC'd allocations or
eventually returned to the OS.
This helps for applications that have high peak heap usage relative to
their regular heap usage (for example, a high-memory initialization
phase). Workbuf memory is roughly proportional to heap size and since
we currently never free workbufs, it's proportional to *peak* heap
size. By freeing workbufs, we can release and reuse this memory for
other purposes when the heap shrinks.
This is somewhat complicated because this costs ~1–2 µs per workbuf
span, so for large heaps it's too expensive to just do synchronously
after mark termination between starting the world and dropping the
worldsema. Hence, we do it asynchronously in the sweeper. This adds a
list of "free" workbuf spans that can be returned to the heap. GC
moves all workbuf spans to this list after mark termination and the
background sweeper drains this list back to the heap. If the sweeper
doesn't finish, that's fine, since getempty can directly reuse any
remaining spans to allocate more workbufs.
Performance impact is negligible. On the x/benchmarks, this reduces
GC-bytes-from-system by 6–11%.
Fixes#19325.
Change-Id: Icb92da2196f0c39ee984faf92d52f29fd9ded7a8
Reviewed-on: https://go-review.googlesource.com/38582
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Currently the runtime allocates workbufs from persistent memory, which
means they can never be freed.
Switch to allocating them from manually-managed heap spans. This
doesn't free them yet, but it puts us in a position to do so.
For #19325.
Change-Id: I94b2512a2f2bbbb456cd9347761b9412e80d2da9
Reviewed-on: https://go-review.googlesource.com/38581
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
This introduces a new type, *gcBits, to use for alloc/mark bitmap
allocations instead of *uint8. This type is marked go:notinheap, so
uses of it correctly eliminate write barriers. Since we now have a
type, this also extracts some common operations to methods both for
convenience and to avoid (*uint8) casts at most use sites.
For #19325.
Change-Id: Id51f734fb2e96b8b7715caa348c8dcd4aef0696a
Reviewed-on: https://go-review.googlesource.com/38580
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
This clarifies that the gcBits type is actually an arena of gcBits and
will let us introduce a new gcBits type representing a single
mark/alloc bitmap allocated from the arena.
For #19325.
Change-Id: Idedf76d202d9174a17c61bcca9d5539e042e2445
Reviewed-on: https://go-review.googlesource.com/38579
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Currently, manually-managed spans are included in memstats.heap_inuse
and memstats.heap_sys, but when we export these stats to the user, we
subtract out how much has been allocated for stack spans from both.
This works for now because stacks are the only manually-managed spans
we have.
However, we're about to use manually-managed spans for more things
that don't necessarily have obvious stats we can use to adjust the
user-presented numbers. Prepare for this by changing the accounting so
manually-managed spans don't count toward heap_inuse or heap_sys. This
makes these fields align with the fields presented to the user and
means we don't have to track more statistics just so we can adjust
these statistics.
For #19325.
Change-Id: I5cb35527fd65587ff23339276ba2c3969e2ad98f
Reviewed-on: https://go-review.googlesource.com/38577
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
We're going to start using manually-managed spans for GC workbufs, so
rename the allocate/free methods and pass in a pointer to the stats to
use instead of using the stack stats directly.
For #19325.
Change-Id: I37df0147ae5a8e1f3cb37d59c8e57a1fcc6f2980
Reviewed-on: https://go-review.googlesource.com/38576
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
We're going to use this free list for other types of manually-managed
memory in the heap.
For #19325.
Change-Id: Ib7e682295133eabfddf3a84f44db43d937bfdd9c
Reviewed-on: https://go-review.googlesource.com/38575
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
We're about to generalize _MSpanStack to be used for other forms of
in-heap manual memory management in the runtime. This is an automated
rename of _MSpanStack to _MSpanManual plus some comment fix-ups.
For #19325.
Change-Id: I1e20a57bb3b87a0d324382f92a3e294ffc767395
Reviewed-on: https://go-review.googlesource.com/38574
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Currently CallersFrames expands each PC to a slice of Frames and then
iteratively returns those Frames. However, this makes it very
difficult to avoid heap allocation: either the Frames slice will be
heap allocated, or, if it uses internal scratch space for small slices
(as it currently does), the Frames object itself has to be heap
allocated.
Fix this, at least in the common case, by expanding each PC
iteratively. We introduce a new pcExpander type that's responsible for
expanding a single PC. This maintains state from one Frame to the next
in the same PC. Frames then becomes a wrapper around this responsible
for feeding it the next PC when the pcExpander runs out of frames for
the current PC.
This makes it possible to stack-allocate a Frames object, which will
make it possible to use this API for PC expansion from within the
runtime itself.
Change-Id: I993463945ab574557cf1d6bedbe79ce7e9cbbdcd
Reviewed-on: https://go-review.googlesource.com/40434
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Lazar <lazard@golang.org>
Prevent a crash if the same type in two plugins had a recursive
definition, either by referring to a pointer to itself or a map existing
with the type as a value type (which creates a recursive definition
through the overflow bucket type).
Fixes#19258
Change-Id: Iac1cbda4c5b6e8edd5e6859a4d5da3bad539a9c6
Reviewed-on: https://go-review.googlesource.com/40292
Run-TryBot: Todd Neal <todd@tneal.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This was unintentionally emptied rather than removed in 9417c022.
Change-Id: Ie6fdcf7ef55e58f12e2a2750ab448aa2d9f94d15
Reviewed-on: https://go-review.googlesource.com/40413
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
OpenBSD 6.0 and later have support for PT_TLS in ld.so(1). Now that OpenBSD
6.1 has been released, OpenBSD 5.9 is no longer officially supported and Go
can start generating PT_TLS for OpenBSD cgo binaries. This also allows us
to remove the workarounds in the OpenBSD cgo runtime.
This change also removes the environ and progname exports - these are now
provided directly by ld.so(1) itself.
Fixes#19932
Change-Id: I42e75ef9feb5dcd4696add5233497e3cbc48ad52
Reviewed-on: https://go-review.googlesource.com/40331
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The hardware divider is an optional component of ARMv7. This patch
detects whether it is available in runtime and use it or not.
1. The hardware divider is detected at startup and a flag is set/clear
according to a perticular bit of runtime.hwcap.
2. Each call of runtime.udiv will check this flag and decide if
use the hardware division instruction.
A rough test shows the performance improves 40-50% for ARMv7. And
the compatibility of ARMv5/v6 is not broken.
fixes#19118
Change-Id: Ic586bc9659ebc169553ca2004d2bdb721df823ac
Reviewed-on: https://go-review.googlesource.com/37496
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Changing mheap_.arena_used requires several steps that are currently
repeated multiple times in mheap_.sysAlloc. Consolidate these into a
single function.
In the future, this will also make it easier to add other auxiliary VM
structures.
Change-Id: Ie68837d2612e1f4ba4904acb1b6b832b15431d56
Reviewed-on: https://go-review.googlesource.com/40151
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The runtime.writeBarrier variable tries to be helpful by telling you
that the compiler also knows about this variable, which you could
probably guess, but doesn't say how the compiler knows about it. In
fact, the compiler has a complete copy in builtin/runtime.go that
needs to be kept in sync. Say so.
Change-Id: Ia7fb0c591cb6f9b8230decce01008b417dfcec89
Reviewed-on: https://go-review.googlesource.com/40150
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
They are dead code already, but the verifier is still not happy.
Don't assemble them at all.
Looks like it has been like that for long. I don't know why it
was ok. Maybe the verifier is now more picky?
Fixes#19884.
Change-Id: Ib806fb73ca469789dec56f52d484cf8baf7a245c
Reviewed-on: https://go-review.googlesource.com/40111
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Dave Cheney <dave@cheney.net>
This code was added recently, and it doesn't seem like the parameter
will be useful in the near future.
Change-Id: I5d64dadb6820c159b588262ab90df2461b5fdf04
Reviewed-on: https://go-review.googlesource.com/39692
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Stack spans don't internally use many of the fields of the mspan,
which means things like the size class and element size get left over
from whatever last used the mspan. This can lead to confusing crashes
and debugging.
Zero these fields or initialize them to something reasonable. This
also lets us simplify some code that currently has to distinguish
between heap and stack spans.
Change-Id: I9bd114e76c147bb32de497045b932f8bf1988bbf
Reviewed-on: https://go-review.googlesource.com/38573
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Commit 44ed88a5a7 moved printing of the "sweep done" gcpacertrace
message so that it is printed when the final sweeper finishes.
However, by this point some other thread has often already observed
that there are no more spans to sweep and zeroed sweepPagesPerByte.
Avoid printing a 0 sweep ratio in the trace when this race happens by
getting the value of the sweep ratio upon entry to sweepone and
printing that.
Change-Id: Iac0c48ae899e12f193267cdfb012c921f8b71c85
Reviewed-on: https://go-review.googlesource.com/39492
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Providing size hint when creating a map allows avoiding re-allocating
underlying data structure if we know how many elements are going to
be inserted. This can be used for example during decoding maps in
gob.
Fixes#19599
Change-Id: I108035fec29391215d2261a73eaed1310b46bab1
Reviewed-on: https://go-review.googlesource.com/38335
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
