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  1. 03 Aug, 2017 3 commits
  3. 02 Aug, 2017 5 commits
  5. 31 Jul, 2017 2 commits
    • Austin Clements's avatar
      runtime: map bitmap and spans during heap initialization · 623e2c46
      Austin Clements authored 
      We lazily map the bitmap and spans areas as the heap grows. However,
right now we're very slightly too lazy. Specifically, the following
can happen on 32-bit:

1. mallocinit fails to allocate any heap arena, so
   arena_used == arena_alloc == arena_end == bitmap.

2. There's less than 256MB between the end of the bitmap mapping and
   the next mapping.

3. On the first allocation, mheap.sysAlloc sees that there's not
   enough room in [arena_alloc, arena_end) because there's no room at
   all. It gets a 256MB mapping from somewhere *lower* in the address
   space than arena_used and sets arena_alloc and arena_end to this
   hole.

4. Since the new arena_alloc is lower than arena_used, mheap.sysAlloc
   doesn't bother to call mheap.setArenaUsed, so we still don't have a
   bitmap mapping or a spans array mapping.

5. mheap.grow, which called mheap.sysAlloc, attempts to fill in the
   spans array and crashes.

Fix this by mapping the metadata regions for the initial arena_used
when the heap is initialized, rather than trying to wait for an
allocation. This maintains the intended invariant that the structures
are always mapped for [arena_start, arena_used).

Fixes #21044.

Change-Id: I4422375a6e234b9f979d22135fc63ae3395946b0
Reviewed-on: https://go-review.googlesource.com/51714
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      623e2c46
    • Austin Clements's avatar
      runtime: fall back to small mmaps if we fail to grow reservation · 780249ee
      Austin Clements authored 
      Right now, if it's possible to grow the arena reservation but
mheap.sysAlloc fails to get 256MB more of memory, it simply fails.
However, on 32-bit we have a fallback path that uses much smaller
mmaps that could take in this situation, but fail to.

This commit fixes mheap.sysAlloc to use a common failure path in case
it can't grow the reservation. On 32-bit, this path includes the
fallback.

Ideally, mheap.sysAlloc would attempt smaller reservation growths
first, but taking the fallback path is a simple change for Go 1.9.

Updates #21044 (fixes one of two issues).

Change-Id: I1e0035ffba986c3551479d5742809e43da5e7c73
Reviewed-on: https://go-review.googlesource.com/51713
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      780249ee
  7. 30 Jul, 2017 1 commit
  9. 28 Jul, 2017 1 commit
  11. 27 Jul, 2017 1 commit
  13. 26 Jul, 2017 2 commits
  15. 25 Jul, 2017 3 commits
  17. 24 Jul, 2017 4 commits
  19. 22 Jul, 2017 1 commit
    • Joe Tsai's avatar
      encoding/json: ignore embedded fields of pointers to unexported non-structs · b8173592
      Joe Tsai authored 
      https://golang.org/cl/33773 fixes the JSON marshaler to avoid serializing
embedded fields on unexported types of non-struct types. However, Go allows
embedding pointer to types, so the check for whether the field is a non-struct
type must first dereference the pointer to get at the underlying type.

Furthermore, due to a edge-case in the behavior of StructField.PkgPath not
being a reliable indicator of whether the field is unexported (see #21122),
we use our own logic to determine whether the field is exported or not.

The logic in this CL may be simplified depending on what happens in #21122.

Fixes #21121
Updates #21122

Change-Id: I8dfd1cdfac8a87950df294a566fb96dfd04fd749
Reviewed-on: https://go-review.googlesource.com/50711Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      b8173592
  21. 21 Jul, 2017 5 commits
  23. 20 Jul, 2017 8 commits
  25. 19 Jul, 2017 4 commits