| Message ID | mcrha5i8222.fsf@iant-glaptop.roam.corp.google.com |
|---|---|
| State | New |
| Headers | show |
"'Ian Lance Taylor <iant@google.com>' via gofrontend-dev" <gofrontend-dev@googlegroups.com> writes: > This patch from Anton Blanchard fixes libgo to adjust to the system page > size when calling madvise. Bootstrapped and ran Go testsuite on > x86_64-unknown-linux-gnu. Committed to mainline and 4.9 branch. Hi, I think this patch will make my Canonical colleagues very happy (and me when I get around to building a 64k page arm64 kernel...). It looks to me like this is also a problem in the gc runtime library though -- should the patch be sent there too? (Apologies if it already has and I missed it, I did look though). Cheers, mwh > Ian > > -- > You received this message because you are subscribed to the Google Groups "gofrontend-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to gofrontend-dev+unsubscribe@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > diff -r 3a53301d24d7 libgo/runtime/mheap.c > --- a/libgo/runtime/mheap.c Tue Apr 22 16:43:35 2014 -0700 > +++ b/libgo/runtime/mheap.c Thu Apr 24 21:18:35 2014 -0700 > @@ -387,7 +387,7 @@ > static uintptr > scavengelist(MSpan *list, uint64 now, uint64 limit) > { > - uintptr released, sumreleased; > + uintptr released, sumreleased, start, end, pagesize; > MSpan *s; > > if(runtime_MSpanList_IsEmpty(list)) > @@ -400,7 +400,17 @@ > mstats.heap_released += released; > sumreleased += released; > s->npreleased = s->npages; > - runtime_SysUnused((void*)(s->start << PageShift), s->npages << PageShift); > + > + start = s->start << PageShift; > + end = start + (s->npages << PageShift); > + > + // Round start up and end down to ensure we > + // are acting on entire pages. > + pagesize = getpagesize(); > + start = ROUND(start, pagesize); > + end &= ~(pagesize - 1); > + if(end > start) > + runtime_SysUnused((void*)start, end - start); > } > } > return sumreleased;
On Sun, Apr 27, 2014 at 2:45 PM, Michael Hudson-Doyle <michael.hudson@linaro.org> wrote: > "'Ian Lance Taylor <iant@google.com>' via gofrontend-dev" > <gofrontend-dev@googlegroups.com> writes: > >> This patch from Anton Blanchard fixes libgo to adjust to the system page >> size when calling madvise. Bootstrapped and ran Go testsuite on >> x86_64-unknown-linux-gnu. Committed to mainline and 4.9 branch. > > Hi, I think this patch will make my Canonical colleagues very happy (and > me when I get around to building a 64k page arm64 kernel...). It looks > to me like this is also a problem in the gc runtime library though -- > should the patch be sent there too? (Apologies if it already has and I > missed it, I did look though). It's a potential problem in the gc runtime library, but I think it's not a real problem at this point, since gc only runs on systems with 4k pages anyhow. Ian
diff -r 3a53301d24d7 libgo/runtime/mheap.c --- a/libgo/runtime/mheap.c Tue Apr 22 16:43:35 2014 -0700 +++ b/libgo/runtime/mheap.c Thu Apr 24 21:18:35 2014 -0700 @@ -387,7 +387,7 @@ static uintptr scavengelist(MSpan *list, uint64 now, uint64 limit) { - uintptr released, sumreleased; + uintptr released, sumreleased, start, end, pagesize; MSpan *s; if(runtime_MSpanList_IsEmpty(list)) @@ -400,7 +400,17 @@ mstats.heap_released += released; sumreleased += released; s->npreleased = s->npages; - runtime_SysUnused((void*)(s->start << PageShift), s->npages << PageShift); + + start = s->start << PageShift; + end = start + (s->npages << PageShift); + + // Round start up and end down to ensure we + // are acting on entire pages. + pagesize = getpagesize(); + start = ROUND(start, pagesize); + end &= ~(pagesize - 1); + if(end > start) + runtime_SysUnused((void*)start, end - start); } } return sumreleased;