diff options
| -rw-r--r-- | gcc/go/gofrontend/MERGE | 2 | ||||
| -rw-r--r-- | libgo/go/runtime/mcentral.go | 9 | ||||
| -rw-r--r-- | libgo/go/runtime/mgcsweep.go | 26 |
3 files changed, 28 insertions, 9 deletions
diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE index 6650b03..9a789b9 100644 --- a/gcc/go/gofrontend/MERGE +++ b/gcc/go/gofrontend/MERGE @@ -1,4 +1,4 @@ -f2cd046a4e0d681c3d21ee547b437d3eab8af268 +82d7205ba9e5c1fe38fd24f89a45caf2e974975b The first line of this file holds the git revision number of the last merge done from the gofrontend repository. diff --git a/libgo/go/runtime/mcentral.go b/libgo/go/runtime/mcentral.go index eaabcb9..150f4fd 100644 --- a/libgo/go/runtime/mcentral.go +++ b/libgo/go/runtime/mcentral.go @@ -56,6 +56,15 @@ retry: c.empty.insertBack(s) unlock(&c.lock) s.sweep(true) + + // With gccgo's conservative GC, the returned span may + // now be full. See the comments in mspan.sweep. + if uintptr(s.allocCount) == s.nelems { + s.freeindex = s.nelems + lock(&c.lock) + goto retry + } + goto havespan } if s.sweepgen == sg-1 { diff --git a/libgo/go/runtime/mgcsweep.go b/libgo/go/runtime/mgcsweep.go index c60214c..d6be349 100644 --- a/libgo/go/runtime/mgcsweep.go +++ b/libgo/go/runtime/mgcsweep.go @@ -296,7 +296,7 @@ func (s *mspan) sweep(preserve bool) bool { } nfreed := s.allocCount - nalloc - // This test is not reliable with gccgo, because of + // This check is not reliable with gccgo, because of // conservative stack scanning. The test boils down to // checking that no new bits have been set in gcmarkBits since // the span was added to the sweep count. New bits are set by @@ -309,16 +309,23 @@ func (s *mspan) sweep(preserve bool) bool { // check to be inaccurate, and it will keep an object live // unnecessarily, but provided the pointer is not really live // it is not otherwise a problem. So we disable the test for gccgo. - if false && nalloc > s.allocCount { - print("runtime: nelems=", s.nelems, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n") - throw("sweep increased allocation count") + nfreedSigned := int(nfreed) + if nalloc > s.allocCount { + // print("runtime: nelems=", s.nelems, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n") + // throw("sweep increased allocation count") + + // For gccgo, adjust the freed count as a signed number. + nfreedSigned = int(s.allocCount) - int(nalloc) + if uintptr(nalloc) == s.nelems { + s.freeindex = s.nelems + } } s.allocCount = nalloc wasempty := s.nextFreeIndex() == s.nelems s.freeindex = 0 // reset allocation index to start of span. if trace.enabled { - getg().m.p.ptr().traceReclaimed += uintptr(nfreed) * s.elemsize + getg().m.p.ptr().traceReclaimed += uintptr(nfreedSigned) * s.elemsize } // gcmarkBits becomes the allocBits. @@ -334,7 +341,7 @@ func (s *mspan) sweep(preserve bool) bool { // But we need to set it before we make the span available for allocation // (return it to heap or mcentral), because allocation code assumes that a // span is already swept if available for allocation. - if freeToHeap || nfreed == 0 { + if freeToHeap || nfreedSigned <= 0 { // The span must be in our exclusive ownership until we update sweepgen, // check for potential races. if s.state != mSpanInUse || s.sweepgen != sweepgen-1 { @@ -347,8 +354,11 @@ func (s *mspan) sweep(preserve bool) bool { atomic.Store(&s.sweepgen, sweepgen) } - if nfreed > 0 && spc.sizeclass() != 0 { - c.local_nsmallfree[spc.sizeclass()] += uintptr(nfreed) + if spc.sizeclass() != 0 { + c.local_nsmallfree[spc.sizeclass()] += uintptr(nfreedSigned) + } + + if nfreedSigned > 0 && spc.sizeclass() != 0 { res = mheap_.central[spc].mcentral.freeSpan(s, preserve, wasempty) // MCentral_FreeSpan updates sweepgen } else if freeToHeap { |