Commit Graph

451 Commits

Author SHA1 Message Date
Elliot Ronaghan
5acef864f2 Don't use compact red-black trees with the pgi compiler
Some bug (either in the red-black tree code, or in the pgi compiler) seems to
cause red-black trees to become unbalanced. This issue seems to go away if we
don't use compact red-black trees. Since red-black trees don't seem to be used
much anymore, I opted for what seems to be an easy fix here instead of digging
in and trying to find the root cause of the bug.

Some context in case it's helpful:

I experienced a ton of segfaults while using pgi as Chapel's target compiler
with jemalloc 4.0.4. The little bit of debugging I did pointed me somewhere
deep in red-black tree manipulation, but I didn't get a chance to investigate
further. It looks like 4.2.0 replaced most uses of red-black trees with
pairing-heaps, which seems to avoid whatever bug I was hitting.

However, `make check_unit` was still failing on the rb test, so I figured the
core issue was just being masked. Here's the `make check_unit` failure:

```sh
=== test/unit/rb ===
test_rb_empty: pass
tree_recurse:test/unit/rb.c:90: Failed assertion: (((_Bool) (((uintptr_t) (left_node)->link.rbn_right_red) & ((size_t)1)))) == (false) --> true != false: Node should be black
test_rb_random:test/unit/rb.c:274: Failed assertion: (imbalances) == (0) --> 1 != 0: Tree is unbalanced
tree_recurse:test/unit/rb.c:90: Failed assertion: (((_Bool) (((uintptr_t) (left_node)->link.rbn_right_red) & ((size_t)1)))) == (false) --> true != false: Node should be black
test_rb_random:test/unit/rb.c:274: Failed assertion: (imbalances) == (0) --> 1 != 0: Tree is unbalanced
node_remove:test/unit/rb.c:190: Failed assertion: (imbalances) == (0) --> 2 != 0: Tree is unbalanced
<jemalloc>: test/unit/rb.c:43: Failed assertion: "pathp[-1].cmp < 0"
test/test.sh: line 22: 12926 Aborted
Test harness error
```

While starting to debug I saw the RB_COMPACT option and decided to check if
turning that off resolved the bug. It seems to have fixed it (`make check_unit`
passes and the segfaults under Chapel are gone) so it seems like on okay
work-around. I'd imagine this has performance implications for red-black trees
under pgi, but if they're not going to be used much anymore it's probably not a
big deal.
2016-09-26 11:08:45 -07:00
Elliot Ronaghan
d1207f0d37 Check for __builtin_unreachable at configure time
Add a configure check for __builtin_unreachable instead of basing its
availability on the __GNUC__ version. On OS X using gcc (a real gcc, not the
bundled version that's just a gcc front-end) leads to a linker assertion:

    https://github.com/jemalloc/jemalloc/issues/266

It turns out that this is caused by a gcc bug resulting from the use of
__builtin_unreachable():

    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57438

To work around this bug, check that __builtin_unreachable() actually works at
configure time, and if it doesn't use abort() instead. The check is based on
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57438#c21.

With this `make check` passes with a homebrew installed gcc-5 and gcc-6.
2016-09-26 10:44:37 -07:00
Jason Evans
20cd2de5ef Add a missing prof_alloc_rollback() call.
In the case where prof_alloc_prep() is called with an over-estimate of
allocation size, and sampling doesn't end up being triggered, the tctx
must be discarded.
2016-06-08 10:12:38 -07:00
Jason Evans
05a9e4ac65 Fix potential VM map fragmentation regression.
Revert 245ae6036c (Support --with-lg-page
values larger than actual page size.), because it could cause VM map
fragmentation if the kernel grows mmap()ed memory downward.

This resolves #391.
2016-06-07 14:21:21 -07:00
Jason Evans
73d3d58dc2 Optimize witness fast path.
Short-circuit commonly called witness functions so that they only
execute in debug builds, and remove equivalent guards from mutex
functions.  This avoids pointless code execution in
witness_assert_lockless(), which is typically called twice per
allocation/deallocation function invocation.

Inline commonly called witness functions so that optimized builds can
completely remove calls as dead code.
2016-05-11 15:38:06 -07:00
Jason Evans
c1e00ef2a6 Resolve bootstrapping issues when embedded in FreeBSD libc.
b2c0d6322d (Add witness, a simple online
locking validator.) caused a broad propagation of tsd throughout the
internal API, but tsd_fetch() was designed to fail prior to tsd
bootstrapping.  Fix this by splitting tsd_t into non-nullable tsd_t and
nullable tsdn_t, and modifying all internal APIs that do not critically
rely on tsd to take nullable pointers.  Furthermore, add the
tsd_booted_get() function so that tsdn_fetch() can probe whether tsd
bootstrapping is complete and return NULL if not.  All dangerous
conversions of nullable pointers are tsdn_tsd() calls that assert-fail
on invalid conversion.
2016-05-10 22:51:33 -07:00
Jason Evans
919e4a0ea9 Add LG_QUANTUM definition for the RISC-V architecture. 2016-05-06 17:15:32 -07:00
Jason Evans
1326010cf4 Update private_symbols.txt. 2016-05-06 14:50:58 -07:00
Jason Evans
3ef51d7f73 Optimize the fast paths of calloc() and [m,d,sd]allocx().
This is a broader application of optimizations to malloc() and free() in
f4a0f32d34 (Fast-path improvement:
reduce # of branches and unnecessary operations.).

This resolves #321.
2016-05-06 14:37:39 -07:00
Jason Evans
c2f970c32b Modify pages_map() to support mapping uncommitted virtual memory.
If the OS overcommits:
- Commit all mappings in pages_map() regardless of whether the caller
  requested committed memory.
- Linux-specific: Specify MAP_NORESERVE to avoid
  unfortunate interactions with heuristic overcommit mode during
  fork(2).

This resolves #193.
2016-05-05 18:56:17 -07:00
Jason Evans
04c3c0f9a0 Add the stats.retained and stats.arenas.<i>.retained statistics.
This resolves #367.
2016-05-03 22:11:35 -07:00
Jason Evans
90827a3f3e Fix huge_palloc() regression.
Split arena_choose() into arena_[i]choose() and use arena_ichoose() for
arena lookup during internal allocation.  This fixes huge_palloc() so
that it always succeeds during extent node allocation.

This regression was introduced by
66cd953514 (Do not allocate metadata via
non-auto arenas, nor tcaches.).
2016-05-03 17:19:15 -07:00
Jason Evans
108c4a11e9 Fix witness/fork() interactions.
Fix witness to clear its list of owned mutexes in the child if
platform-specific malloc_mutex code re-initializes mutexes rather than
unlocking them.
2016-04-26 10:47:22 -07:00
Jason Evans
174c0c3a9c Fix fork()-related lock rank ordering reversals. 2016-04-25 23:16:20 -07:00
Jason Evans
71d94828a2 Fix degenerate mb_write() compilation error.
This resolves #375.
2016-04-22 21:27:17 -07:00
Jason Evans
19ff2cefba Implement the arena.<i>.reset mallctl.
This makes it possible to discard all of an arena's allocations in a
single operation.

This resolves #146.
2016-04-22 15:20:06 -07:00
Jason Evans
66cd953514 Do not allocate metadata via non-auto arenas, nor tcaches.
This assures that all internally allocated metadata come from the
first opt_narenas arenas, i.e. the automatically multiplexed arenas.
2016-04-22 15:19:59 -07:00
Jason Evans
b6e07d2389 Fix malloc_mutex_assert_[not_]owner() for --enable-lazy-lock case. 2016-04-18 15:42:09 -07:00
Jason Evans
ab0cfe01fa Update private_symbols.txt.
Change test-related mangling to simplify symbol filtering.

The following commands can be used to detect missing/obsolete symbol
mangling, with the caveat that the full set of symbols is based on the
union of symbols generated by all configurations, some of which are
platform-specific:

./autogen.sh --enable-debug --enable-prof --enable-lazy-lock
make all tests
nm -a lib/libjemalloc.a src/*.jet.o \
  |grep " [TDBCR] " \
  |awk '{print $3}' \
  |sed -e 's/^\(je_\|jet_\(n_\)\?\)\([a-zA-Z0-9_]*\)/\3/g' \
  |LC_COLLATE=C sort -u \
  |grep -v \
   -e '^\(malloc\|calloc\|posix_memalign\|aligned_alloc\|realloc\|free\)$' \
   -e '^\(m\|r\|x\|s\|d\|sd\|n\)allocx$' \
   -e '^mallctl\(\|nametomib\|bymib\)$' \
   -e '^malloc_\(stats_print\|usable_size\|message\)$' \
   -e '^\(memalign\|valloc\)$' \
   -e '^__\(malloc\|memalign\|realloc\|free\)_hook$' \
   -e '^pthread_create$' \
  > /tmp/private_symbols.txt
2016-04-18 15:23:35 -07:00
Rajat Goel
a0c632c9d5 Update private_symbols.txt
Add 4 missing symbols
2016-04-18 11:54:09 -07:00
Jason Evans
1423ee9016 Fix style nits. 2016-04-17 13:44:59 -07:00
Jason Evans
1b5830178f Fix malloc_mutex_[un]lock() to conditionally check witness.
Also remove tautological cassert(config_debug) calls.
2016-04-17 13:44:59 -07:00
Jason Evans
2288424325 s/MALLOC_MUTEX_RANK_OMIT/WITNESS_RANK_OMIT/
This fixes a compilation error caused by
b2c0d6322d (Add witness, a simple online
locking validator.).

This resolves #375.
2016-04-14 12:18:55 -07:00
Jason Evans
a15841cc7d Fix a compilation error.
Fix a compilation error that occurs if Valgrind is not enabled.  This
regression was caused by b2c0d6322d (Add
witness, a simple online locking validator.).
2016-04-14 02:12:33 -07:00
Jason Evans
b2c0d6322d Add witness, a simple online locking validator.
This resolves #358.
2016-04-14 02:09:28 -07:00
Jason Evans
8413463f3a Fix a style nit. 2016-04-12 23:18:25 -07:00
Jason Evans
667eca2ac2 Simplify RTREE_HEIGHT_MAX definition.
Use 1U rather than ZU(1) in macro definitions, so that the preprocessor
can evaluate the resulting expressions.
2016-04-11 02:35:00 -07:00
Jason Evans
245ae6036c Support --with-lg-page values larger than actual page size.
During over-allocation in preparation for creating aligned mappings,
allocate one more page than necessary if PAGE is the actual page size,
so that trimming still succeeds even if the system returns a mapping
that has less than PAGE alignment.  This allows compiling with e.g. 64
KiB "pages" on systems that actually use 4 KiB pages.

Note that for e.g. --with-lg-page=21, it is also necessary to increase
the chunk size (e.g. --with-malloc-conf=lg_chunk:22) so that there are
at least two "pages" per chunk.  In practice this isn't a particularly
compelling configuration because so much (unusable) virtual memory is
dedicated to chunk headers.
2016-04-11 02:35:00 -07:00
Jason Evans
96aa67aca8 Clean up char vs. uint8_t in junk filling code.
Consistently use uint8_t rather than char for junk filling code.
2016-04-11 02:26:35 -07:00
Jason Evans
c6a2c39404 Refactor/fix ph.
Refactor ph to support configurable comparison functions.  Use a cpp
macro code generation form equivalent to the rb macros so that pairing
heaps can be used for both run heaps and chunk heaps.

Remove per node parent pointers, and instead use leftmost siblings' prev
pointers to track parents.

Fix multi-pass sibling merging to iterate over intermediate results
using a FIFO, rather than a LIFO.  Use this fixed sibling merging
implementation for both merge phases of the auxiliary twopass algorithm
(first merging the aux list, then replacing the root with its merged
children).  This fixes both degenerate merge behavior and the potential
for deep recursion.

This regression was introduced by
6bafa6678f (Pairing heap).

This resolves #371.
2016-04-11 02:15:42 -07:00
Jason Evans
2ee2f1ec57 Reduce differences between alternative bitmap implementations. 2016-04-06 10:38:47 -07:00
Jason Evans
4a8abbb400 Fix bitmap_sfu() regression.
Fix bitmap_sfu() to shift by LG_BITMAP_GROUP_NBITS rather than
hard-coded 6 when using linear (non-USE_TREE) bitmap search.  In
practice this affects only 64-bit systems for which sizeof(long) is not
8 (i.e. Windows), since USE_TREE is defined for 32-bit systems.

This regression was caused by b8823ab026
(Use linear scan for small bitmaps).

This resolves #368.
2016-04-06 10:32:06 -07:00
Chris Peterson
a82070ef5f Add JEMALLOC_ALLOC_JUNK and JEMALLOC_FREE_JUNK macros
Replace hardcoded 0xa5 and 0x5a junk values with JEMALLOC_ALLOC_JUNK and
JEMALLOC_FREE_JUNK macros, respectively.
2016-03-31 11:23:29 -07:00
Jason Evans
ce7c0f999b Fix potential chunk leaks.
Move chunk_dalloc_arena()'s implementation into chunk_dalloc_wrapper(),
so that if the dalloc hook fails, proper decommit/purge/retain cascading
occurs.  This fixes three potential chunk leaks on OOM paths, one during
dss-based chunk allocation, one during chunk header commit (currently
relevant only on Windows), and one during rtree write (e.g. if rtree
node allocation fails).

Merge chunk_purge_arena() into chunk_purge_default() (refactor, no
change to functionality).
2016-03-30 18:36:04 -07:00
Chris Peterson
f3060284c5 Remove unused arenas_extend() function declaration.
The arenas_extend() function was renamed to arenas_init() in commit
8bb3198f72, but its function declaration
was not removed from jemalloc_internal.h.in.
2016-03-26 01:03:24 -07:00
Jason Evans
af3184cac0 Use abort() for fallback implementations of unreachable(). 2016-03-24 01:42:08 -07:00
Jason Evans
61a6dfcd5f Constify various internal arena APIs. 2016-03-23 16:15:42 -07:00
Jason Evans
6a885198c2 Always inline performance-critical rtree operations. 2016-03-23 16:15:42 -07:00
Jason Evans
6c460ad91b Optimize rtree_get().
Specialize fast path to avoid code that cannot execute for dependent
loads.

Manually unroll.
2016-03-22 17:54:35 -07:00
Jason Evans
22af74e106 Refactor out signed/unsigned comparisons. 2016-03-15 09:40:02 -07:00
Jason Evans
824b947be0 Add (size_t) casts to MALLOCX_ALIGN().
Add (size_t) casts to MALLOCX_ALIGN() macros so that passing the integer
constant 0x80000000 does not cause a compiler warning about invalid
shift amount.

This resolves #354.
2016-03-11 10:11:56 -08:00
Rajeev Misra
ca18f2834e typecast address to pointer to byte to avoid unaligned memory access error 2016-03-10 22:49:05 -08:00
Jason Evans
613cdc80f6 Convert arena_bin_t's runs from a tree to a heap. 2016-03-08 13:48:27 -08:00
Dave Watson
4a0dbb5ac8 Use pairing heap for arena->runs_avail
Use pairing heap instead of red black tree in arena runs_avail.  The
extra links are unioned with the bitmap_t, so this change doesn't use
any extra memory.

Canaries show this change to be a 1% cpu win, and 2% latency win.  In
particular, large free()s, and small bin frees are now O(1) (barring
coalescing).

I also tested changing bin->runs to be a pairing heap, but saw a much
smaller win, and it would mean increasing the size of arena_run_s by two
pointers, so I left that as an rb-tree for now.
2016-03-08 13:48:27 -08:00
Jason Evans
f8d80d62a8 Refactor ph_merge_ordered() out of ph_merge(). 2016-03-08 13:48:27 -08:00
Dave Watson
6bafa6678f Pairing heap
Initial implementation of a twopass pairing heap with aux list.
Research papers linked in comments.

Where search/nsearch/last aren't needed, this gives much faster first(),
delete(), and insert().  Insert is O(1), and first/delete don't have to
walk the whole tree.

Also tested rb_old with parent pointers - it was better than the current
rb.h for memory loads, but still much worse than a pairing heap.

An array-based heap would be much faster if everything fits in memory,
but on a cold cache it has many more memory loads for most operations.
2016-03-08 13:46:19 -08:00
Jason Evans
022f6891fa Avoid a potential innocuous compiler warning.
Add a cast to avoid comparing a ssize_t value to a uint64_t value that
is always larger than a 32-bit ssize_t.  This silences an innocuous
compiler warning from e.g. gcc 4.2.1 about the comparison always having
the same result.
2016-03-02 22:45:37 -08:00
Dmitri Smirnov
86478b2998 Remove errno overrides. 2016-02-29 10:45:49 -08:00
Jason Evans
3c07f803aa Fix stats.arenas.<i>.[...] for --disable-stats case.
Add missing stats.arenas.<i>.{dss,lg_dirty_mult,decay_time}
initialization.

Fix stats.arenas.<i>.{pactive,pdirty} to read under the protection of
the arena mutex.
2016-02-27 20:40:13 -08:00
Jason Evans
69acd25a64 Add/alphabetize private symbols. 2016-02-27 15:35:52 -08:00