code review 6643046: runtime: sizeclass in MSpan should be int32. (issue 6643046)

[dio...@gmail.com]

Reviewers: golang-dev_googlegroups.com,

Message:
Hello golan...@googlegroups.com (cc: golan...@googlegroups.com,
r...@golang.org),

I'd like you to review this change to
https://code.google.com/p/go/


Description:
runtime: sizeclass in MSpan should be int32.

Please review this at http://codereview.appspot.com/6643046/

Affected files:
M src/pkg/runtime/malloc.h


Index: src/pkg/runtime/malloc.h
===================================================================
--- a/src/pkg/runtime/malloc.h
+++ b/src/pkg/runtime/malloc.h
@@ -358,7 +358,7 @@
uintptr npages; // number of pages in span
MLink *freelist; // list of free objects
uint32 ref; // number of allocated objects in this span
- uint32 sizeclass; // size class
+ int32 sizeclass; // size class
uintptr elemsize; // computed from sizeclass or from npages
uint32 state; // MSpanInUse etc
int64 unusedsince; // First time spotted by GC in MSpanFree state

[minux]

any explanations?

[Jingcheng Zhang]

All sizeclass in runrime are int32. I suspect this uint32 sizeclass is a neglect.

在 2012-10-11 PM1:21，"minux" <minu...@gmail.com>写道：

any explanations?

[Dave Cheney]

On the contrary, I think this is the only one that is correct. How can you have something that is -5 bytes big?

[dio...@gmail.com]

"sizeclass" is different with "size". It is the class of size, not the
size itself. There are currently 61 sizeclasses (through an enum value
NumSizeClasses) defined for allocation.

On 2012/10/11 07:23:47, dfc wrote:
> On the contrary, I think this is the only one that is correct. How can
you have
> something that is -5 bytes big?

> On 11/ can10/2012, at 17:30, Jingcheng Zhang <mailto:dio...@gmail.com>

wrote:

> > All sizeclass in runrime are int32. I suspect this uint32 sizeclass
is a
> neglect.
> >
> > 在 2012-10-11 PM1:21，"minux" <minu...@gmail.com>写道：
> >> any explanations?

http://codereview.appspot.com/6643046/

[minux]

LGTM, will wait for others' opinion before submit.

Have you signed the CLA as described at

http://golang.org/doc/contribute.html#copyright?

[dio...@gmail.com]

Just signed it, the page said it would process my submission shortly,
not sure whether it is completed now.

http://codereview.appspot.com/6643046/

[r...@golang.org]

It's hard to get excited about this but okay.


https://codereview.appspot.com/6643046/