Keith Randall e410a527b2 runtime: simplify chan ops, take 2 ... This change is the same as CL #9345 which was reverted, except for a small bug fix. The only change is to the body of sendDirect and its callsite. Also added a test. The problem was during a channel send operation. The target of the send was a sleeping goroutine waiting to receive. We basically do: 1) Read the destination pointer out of the sudog structure 2) Copy the value we're sending to that destination pointer Unfortunately, the previous change had a goroutine suspend point between 1 & 2 (the call to sendDirect). At that point the destination goroutine's stack could be copied (shrunk). The pointer we read in step 1 is no longer valid for step 2. Fixed by not allowing any suspension points between 1 & 2. I suspect the old code worked correctly basically by accident. Fixes #13169 The original 9345: This change removes the retry mechanism we use for buffered channels. Instead, any sender waking up a receiver or vice versa completes the full protocol with its counterpart. This means the counterpart does not need to relock the channel when it wakes up. (Currently buffered channels need to relock on wakeup.) For sends on a channel with waiting receivers, this change replaces two copies (sender->queue, queue->receiver) with one (sender->receiver). For receives on channels with a waiting sender, two copies are still required. This change unifies to a large degree the algorithm for buffered and unbuffered channels, simplifying the overall implementation. Fixes #11506 Change-Id: I57dfa3fc219cffa4d48301ee15fe5479299efa09 Reviewed-on: https://go-review.googlesource.com/16740 Reviewed-by: Ian Lance Taylor <iant@golang.org>		2015-11-08 23:20:25 +00:00
..
bench	test/bench/shootout: fix build	2015-07-31 17:37:58 +00:00
bugs	test: migrate remaining tests to run.go	2014-12-22 22:41:34 +00:00
chan	Fix several out of date references to 4g/5g/6g/8g/9g.	2015-06-26 03:38:21 +00:00
ddd2.dir
dwarf
fixedbugs	runtime: simplify chan ops, take 2	2015-11-08 23:20:25 +00:00
import2.dir
import4.dir	test: adjust gccgo expected import errors	2015-10-07 14:37:44 +00:00
interface	cmd/internal/gc: improve "type *X has no field or method M" message	2015-05-07 16:21:57 +00:00
ken
method4.dir	cmd/gc: do not omit wrapper for expression (interface{...}).F	2014-01-07 13:26:48 +01:00
safe
stress	build: adjustments for move from src/pkg to src	2014-09-08 00:06:45 -04:00
syntax	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
64bit.go
235.go
alias1.go
alias.go
append.go
args.go
assign1.go
assign.go	cmd/gc: prohibit short variable declarations containing duplicate symbols	2014-10-06 17:16:39 -04:00
bigalg.go
bigmap.go
blank1.go
blank.go
bom.go
bombad.go
bounds.go
chancap.go
chanlinear.go	runtime: test for linear enqueue/dequeue behavior	2014-12-08 22:18:17 +00:00
char_lit1.go
char_lit.go
clearfat.go	[dev.power64] 9g: fix under-zeroing in clearfat	2014-10-31 11:08:27 -04:00
closedchan.go
closure1.go	cmd/gc: capture variables by value	2015-01-29 13:07:30 +00:00
closure2.go	cmd/gc: fix capturing by value for range statements	2015-02-03 15:48:48 +00:00
closure.go
cmp6.go	cmd/gc: do not consider length zero arrays as comparable.	2014-01-31 00:30:56 +01:00
cmp.go	Fix several out of date references to 4g/5g/6g/8g/9g.	2015-06-26 03:38:21 +00:00
cmplx.go
cmplxdivide1.go
cmplxdivide.c	test: comment the behavior and use of cmplxdivide*	2015-01-15 00:00:06 +00:00
cmplxdivide.go	test: comment the behavior and use of cmplxdivide*	2015-01-15 00:00:06 +00:00
complit1.go	cmd/internal/gc: accept map literals with omitted key type	2015-06-04 02:31:38 +00:00
complit.go
compos.go
const1.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
const2.go
const3.go
const4.go	all: link to https instead of http	2015-07-11 14:36:33 +00:00
const5.go	all: link to https instead of http	2015-07-11 14:36:33 +00:00
const6.go
const.go	cmd/compile: allow huge rsh in constants arithmetic	2015-08-21 20:27:22 +00:00
convert1.go
convert3.go
convert.go
convlit1.go
convlit.go	cmd/internal/gc: unsafe.Pointer constants may only be converted to uintptr	2015-05-07 23:54:28 +00:00
convT2X.go
copy.go
crlf.go
ddd1.go
ddd2.go
ddd.go
decl.go
declbad.go
defer.go
deferfin.go	runtime: combine small NoScan allocations	2014-01-24 22:35:11 +04:00
deferprint.go
deferprint.out
divide.go
divmod.go	all: fix a few spelling errors in source comments	2013-12-27 08:59:02 -08:00
empty.go
env.go
eof1.go
eof.go
errchk	Fix several out of date references to 4g/5g/6g/8g/9g.	2015-06-26 03:38:21 +00:00
escape2.go	cmd/compile: escape analysis, don't always escape variadic args	2015-10-04 20:45:35 +00:00
escape2n.go	cmd/compile: escape analysis, don't always escape variadic args	2015-10-04 20:45:35 +00:00
escape3.go
escape4.go	cmd/internal/gc: transitive inlining	2015-02-26 17:36:00 +00:00
escape5.go	cmd/internal/gc: move check for large-hence-heap-allocated types into escape analysis	2015-05-22 02:13:54 +00:00
escape_array.go	cmd/internal/gc: move check for large-hence-heap-allocated types into escape analysis	2015-05-22 02:13:54 +00:00
escape_calls.go	cmd/internal/gc: make indirect calls properly escape-y	2015-05-22 01:36:11 +00:00
escape_closure.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_field.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_iface.go	cmd/compile: add case for ODOTTYPE to escwalk	2015-07-30 17:39:44 +00:00
escape_indir.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_level.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_map.go	test: add tests for escape analysis of interface conversions	2015-03-28 16:15:27 +00:00
escape_param.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_slice.go	cmd/internal/gc: extend escape analysis to pointers in slices	2015-05-18 15:34:39 +00:00
escape_struct_param1.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_struct_param2.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_struct_return.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape.go
fibo.go	Fix whitespace (use blanks consistently).	2014-12-08 22:22:58 +00:00
finprofiled.go	runtime: fix finalization and profiling of tiny allocations	2015-11-03 18:57:18 +00:00
float_lit2.go	test: fix two typos in float_lit2.go	2014-05-21 17:19:12 -04:00
float_lit3.go	test/float_lit2.go: rewrite to test values near boundaries	2014-05-21 17:12:06 -04:00
float_lit.go
floatcmp.go
for.go
func1.go
func2.go
func3.go
func4.go
func5.go
func6.go	Fix several out of date references to 4g/5g/6g/8g/9g.	2015-06-26 03:38:21 +00:00
func7.go	Fix several out of date references to 4g/5g/6g/8g/9g.	2015-06-26 03:38:21 +00:00
func8.go	test: use go:noinline consistently	2015-11-03 02:01:34 +00:00
func.go
funcdup2.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
funcdup.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
gc1.go
gc2.go	test: check for build constraints only upto the first blank line	2015-02-06 05:36:26 +00:00
gc.go
gcstring.go	runtime: fix empty string handling in garbage collector	2014-03-11 23:58:39 -04:00
goprint.go
goprint.out
goto.go	Revert "cmd/internal/gc: ignore declarations of types for goto validation"	2015-05-15 16:35:49 +00:00
heapsampling.go	test: disable flaky heapsampling test for now	2015-10-30 20:48:03 +00:00
helloworld.go
helloworld.out
if.go
import1.go	test: match gccgo import error messages	2013-12-12 19:02:11 -08:00
import2.go
import4.go
import5.go
import.go
index0.go
index1.go
index2.go
index.go	Fix several out of date references to 4g/5g/6g/8g/9g.	2015-06-26 03:38:21 +00:00
indirect1.go
indirect.go
init1.go	test: deflake init1.go test, tighten its bounds	2015-02-13 22:13:56 +00:00
init.go
initcomma.go
initialize.go
initializerr.go
initloop.go	cmd/compile: use []*Node instead of NodeList in sinit	2015-09-05 02:25:01 +00:00
inline.go	cmd/compile: add support for a go:noinline directive	2015-10-29 23:16:27 +00:00
int_lit.go
intcvt.go
iota.go
label1.go
label.go
linkx_run.go	cmd/link: detect -X setting non-string variable	2015-06-29 20:28:36 +00:00
linkx.go	cmd/link: detect -X setting non-string variable	2015-06-29 20:28:36 +00:00
literal.go
live1.go	cmd/gc: correct liveness for fat variables	2014-02-15 10:58:55 -05:00
live2.go	cmd/gc: allocate non-escaping maps on stack	2015-02-12 09:53:52 +00:00
live.go	test: add -update_errors flag to run script	2015-04-10 11:33:42 +00:00
mallocfin.go
map1.go
map.go	test/mapnan.go: add regression test for non-empty interfaces.	2014-08-06 17:02:55 -04:00
maplinear.go	test: make maplinear more robust	2014-10-27 18:59:02 -04:00
method1.go
method2.go
method3.go
method4.go
method5.go
method.go
named1.go	cmd/gc: comma-ok assignments produce untyped bool as 2nd result	2014-08-11 16:11:55 -07:00
named.go
nil.go
nilcheck.go	cmd/gc: optimize existence-only map lookups	2015-01-07 22:36:06 +00:00
nilptr2.go
nilptr3.go	cmd/7g: enable peephole optimizer	2015-04-08 08:16:54 +00:00
nilptr4.go	cmd/gc: fix bad checknil with ints on 32 bit compilers	2014-02-26 12:25:13 -08:00
nilptr.go
nosplit.go	cmd/internal/obj/arm64: reject misaligned stack frames, except empty frames	2015-07-29 21:37:12 +00:00
nul1.go
parentype.go
peano.go
print.go	runtime: move built-in print routines to go.	2014-07-31 13:48:48 -07:00
print.out	runtime: move built-in print routines to go.	2014-07-31 13:48:48 -07:00
printbig.go
printbig.out
range.go	cmd/gc: implement 'for range x {'	2014-07-16 19:27:10 -04:00
recover1.go
recover2.go
recover3.go
recover4.go	test: move allocation before munmap in recover4	2015-09-16 08:51:48 +00:00
recover.go	test: add more cases to recover.go	2014-10-22 08:06:15 -07:00
rename1.go
rename.go
reorder2.go	test: use go:noinline consistently	2015-11-03 02:01:34 +00:00
reorder.go
return.go
rotate0.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate1.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate2.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate3.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate.go
run.go	runtime: fix x86 stack trace for call to heap memory	2015-07-13 19:42:35 +00:00
rune.go
runtime.go
shift1.go	test: avoid "declared but not used" errors in shift1.go	2014-07-20 12:25:24 -07:00
shift2.go
sieve.go
sigchld.go	test: skip SIGCHLD test on Plan 9	2014-01-29 09:28:23 +01:00
sigchld.out
simassign.go
sinit_run.go	all: retire architecture letter in file names, public API	2015-05-21 17:32:17 +00:00
sinit.go	cmd/compile: allow static init for unsafe.Pointer(&x) where x is global	2015-07-07 21:51:57 +00:00
sizeof.go
slice3.go	cmd/gc, runtime: treat slices and strings like pointers in garbage collection	2014-08-25 14:38:19 -04:00
slice3err.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
slicecap.go	cmd/gc, runtime: treat slices and strings like pointers in garbage collection	2014-08-25 14:38:19 -04:00
sliceopt.go	cmd/internal/gc: optimize slice + write barrier	2015-05-13 19:20:39 +00:00
solitaire.go
stack.go
string_lit.go	test: add []rune case to string_lit.go	2013-12-12 17:17:02 -08:00
stringrange.go
struct0.go
switch3.go
switch4.go
switch.go
tinyfin.go	runtime: fix finalization and profiling of tiny allocations	2015-11-03 18:57:18 +00:00
torture.go	cmd/8g: don't allocate a register early for cap(CHAN).	2014-07-01 09:20:51 +02:00
turing.go
typecheck.go	cmd/gc: silence assignment errors to undefined symbols	2014-01-03 21:03:20 +01:00
typecheckloop.go	cmd/compile: convert typecheck_stack to []*Node	2015-09-06 23:50:51 +00:00
typeswitch1.go
typeswitch2.go
typeswitch3.go
typeswitch.go
undef.go
utf.go
varerr.go
varinit.go
writebarrier.go	cmd/internal/gc: add missing write barrier in append(x, BigStructWithPointers)	2015-05-19 15:28:29 +00:00
zerodivide.go