Implement chunk hook support for page run commit/decommit.

Cascade from decommit to purge when purging unused dirty pages, so that
it is possible to decommit cleaned memory rather than just purging.  For
non-Windows debug builds, decommit runs rather than purging them, since
this causes access of deallocated runs to segfault.

This resolves #251.
This commit is contained in:
Jason Evans
2015-08-04 10:49:46 -07:00
parent 5716d97f75
commit 8fadb1a8c2
15 changed files with 561 additions and 283 deletions

View File

@@ -22,45 +22,50 @@ static bool did_merge;
void *
chunk_alloc(void *new_addr, size_t size, size_t alignment, bool *zero,
unsigned arena_ind)
bool *commit, unsigned arena_ind)
{
TRACE_HOOK("%s(new_addr=%p, size=%zu, alignment=%zu, *zero=%s, "
"arena_ind=%u)\n", __func__, new_addr, size, alignment, *zero ?
"true" : "false", arena_ind);
"*commit=%s, arena_ind=%u)\n", __func__, new_addr, size, alignment,
*zero ? "true" : "false", *commit ? "true" : "false", arena_ind);
did_alloc = true;
return (old_hooks.alloc(new_addr, size, alignment, zero, arena_ind));
return (old_hooks.alloc(new_addr, size, alignment, zero, commit,
arena_ind));
}
bool
chunk_dalloc(void *chunk, size_t size, unsigned arena_ind)
chunk_dalloc(void *chunk, size_t size, bool committed, unsigned arena_ind)
{
TRACE_HOOK("%s(chunk=%p, size=%zu, arena_ind=%u)\n", __func__, chunk,
size, arena_ind);
TRACE_HOOK("%s(chunk=%p, size=%zu, committed=%s, arena_ind=%u)\n",
__func__, chunk, size, committed ? "true" : "false", arena_ind);
did_dalloc = true;
if (!do_dalloc)
return (true);
return (old_hooks.dalloc(chunk, size, arena_ind));
return (old_hooks.dalloc(chunk, size, committed, arena_ind));
}
bool
chunk_commit(void *chunk, size_t size, unsigned arena_ind)
chunk_commit(void *chunk, size_t size, size_t offset, size_t length,
unsigned arena_ind)
{
TRACE_HOOK("%s(chunk=%p, size=%zu, arena_ind=%u)\n", __func__, chunk,
size, arena_ind);
TRACE_HOOK("%s(chunk=%p, size=%zu, offset=%zu, length=%zu, "
"arena_ind=%u)\n", __func__, chunk, size, offset, length,
arena_ind);
did_commit = true;
memset(chunk, 0, size);
memset((void *)((uintptr_t)chunk + offset), 0, length);
return (false);
}
bool
chunk_decommit(void *chunk, size_t size, unsigned arena_ind)
chunk_decommit(void *chunk, size_t size, size_t offset, size_t length,
unsigned arena_ind)
{
TRACE_HOOK("%s(chunk=%p, size=%zu, arena_ind=%u)\n", __func__, chunk,
size, arena_ind);
TRACE_HOOK("%s(chunk=%p, size=%zu, offset=%zu, length=%zu, "
"arena_ind=%u)\n", __func__, chunk, size, offset, length,
arena_ind);
did_decommit = true;
return (!do_decommit);
}
@@ -106,7 +111,7 @@ chunk_merge(void *chunk_a, size_t size_a, void *chunk_b, size_t size_b,
TEST_BEGIN(test_chunk)
{
void *p;
size_t old_size, new_size, huge0, huge1, huge2, sz;
size_t old_size, new_size, large0, large1, huge0, huge1, huge2, sz;
chunk_hooks_t new_hooks = {
chunk_alloc,
chunk_dalloc,
@@ -134,8 +139,14 @@ TEST_BEGIN(test_chunk)
assert_ptr_ne(old_hooks.split, chunk_split, "Unexpected split error");
assert_ptr_ne(old_hooks.merge, chunk_merge, "Unexpected merge error");
/* Get huge size classes. */
/* Get large size classes. */
sz = sizeof(size_t);
assert_d_eq(mallctl("arenas.lrun.0.size", &large0, &sz, NULL, 0), 0,
"Unexpected arenas.lrun.0.size failure");
assert_d_eq(mallctl("arenas.lrun.1.size", &large1, &sz, NULL, 0), 0,
"Unexpected arenas.lrun.1.size failure");
/* Get huge size classes. */
assert_d_eq(mallctl("arenas.hchunk.0.size", &huge0, &sz, NULL, 0), 0,
"Unexpected arenas.hchunk.0.size failure");
assert_d_eq(mallctl("arenas.hchunk.1.size", &huge1, &sz, NULL, 0), 0,
@@ -196,10 +207,29 @@ TEST_BEGIN(test_chunk)
did_purge = false;
assert_zu_eq(xallocx(p, huge1, 0, 0), huge1,
"Unexpected xallocx() failure");
assert_true(did_purge, "Unexpected purge");
assert_true(did_purge, "Expected purge");
dallocx(p, 0);
}
/* Test decommit for large allocations. */
do_decommit = true;
p = mallocx(large1, 0);
assert_ptr_not_null(p, "Unexpected mallocx() error");
assert_d_eq(mallctl("arena.0.purge", NULL, NULL, NULL, 0), 0,
"Unexpected arena.0.purge error");
did_decommit = false;
assert_zu_eq(xallocx(p, large0, 0, 0), large0,
"Unexpected xallocx() failure");
assert_d_eq(mallctl("arena.0.purge", NULL, NULL, NULL, 0), 0,
"Unexpected arena.0.purge error");
assert_true(did_decommit, "Expected decommit");
did_commit = false;
assert_zu_eq(xallocx(p, large1, 0, 0), large1,
"Unexpected xallocx() failure");
assert_true(did_commit, "Expected commit");
dallocx(p, 0);
do_decommit = false;
/* Make sure non-huge allocation succeeds. */
p = mallocx(42, 0);
assert_ptr_not_null(p, "Unexpected mallocx() error");