Commit Graph

28 Commits

Author SHA1 Message Date
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
b2c0d6322d Add witness, a simple online locking validator.
This resolves #358.
2016-04-14 02:09:28 -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
Dmitry-Me
78ae1ac486 Reduce variable scope.
This resolves #274.
2015-09-15 11:19:20 -07:00
Jason Evans
03bf5b67be Try to decommit new chunks.
Always leave decommit disabled on non-Windows systems.
2015-08-12 10:26:54 -07:00
Jason Evans
8fadb1a8c2 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.
2015-08-07 00:50:58 -07:00
Jason Evans
b49a334a64 Generalize chunk management hooks.
Add the "arena.<i>.chunk_hooks" mallctl, which replaces and expands on
the "arena.<i>.chunk.{alloc,dalloc,purge}" mallctls.  The chunk hooks
allow control over chunk allocation/deallocation, decommit/commit,
purging, and splitting/merging, such that the application can rely on
jemalloc's internal chunk caching and retaining functionality, yet
implement a variety of chunk management mechanisms and policies.

Merge the chunks_[sz]ad_{mmap,dss} red-black trees into
chunks_[sz]ad_retained.  This slightly reduces how hard jemalloc tries
to honor the dss precedence setting; prior to this change the precedence
setting was also consulted when recycling chunks.

Fix chunk purging.  Don't purge chunks in arena_purge_stashed(); instead
deallocate them in arena_unstash_purged(), so that the dirty memory
linkage remains valid until after the last time it is used.

This resolves #176 and #201.
2015-08-03 21:49:02 -07:00
Jason Evans
738e089a2e Rename "dirty chunks" to "cached chunks".
Rename "dirty chunks" to "cached chunks", in order to avoid overloading
the term "dirty".

Fix the regression caused by 339c2b23b2
(Fix chunk_unmap() to propagate dirty state.), and actually address what
that change attempted, which is to only purge chunks once, and propagate
whether zeroed pages resulted into chunk_record().
2015-02-18 01:15:50 -08:00
Jason Evans
ee41ad409a Integrate whole chunks into unused dirty page purging machinery.
Extend per arena unused dirty page purging to manage unused dirty chunks
in aaddtion to unused dirty runs.  Rather than immediately unmapping
deallocated chunks (or purging them in the --disable-munmap case), store
them in a separate set of trees, chunks_[sz]ad_dirty.  Preferrentially
allocate dirty chunks.  When excessive unused dirty pages accumulate,
purge runs and chunks in ingegrated LRU order (and unmap chunks in the
--enable-munmap case).

Refactor extent_node_t to provide accessor functions.
2015-02-16 21:02:17 -08:00
Jason Evans
cbf3a6d703 Move centralized chunk management into arenas.
Migrate all centralized data structures related to huge allocations and
recyclable chunks into arena_t, so that each arena can manage huge
allocations and recyclable virtual memory completely independently of
other arenas.

Add chunk node caching to arenas, in order to avoid contention on the
base allocator.

Use chunks_rtree to look up huge allocations rather than a red-black
tree.  Maintain a per arena unsorted list of huge allocations (which
will be needed to enumerate huge allocations during arena reset).

Remove the --enable-ivsalloc option, make ivsalloc() always available,
and use it for size queries if --enable-debug is enabled.  The only
practical implications to this removal are that 1) ivsalloc() is now
always available during live debugging (and the underlying radix tree is
available during core-based debugging), and 2) size query validation can
no longer be enabled independent of --enable-debug.

Remove the stats.chunks.{current,total,high} mallctls, and replace their
underlying statistics with simpler atomically updated counters used
exclusively for gdump triggering.  These statistics are no longer very
useful because each arena manages chunks independently, and per arena
statistics provide similar information.

Simplify chunk synchronization code, now that base chunk allocation
cannot cause recursive lock acquisition.
2015-02-12 00:15:56 -08:00
Daniel Micay
879e76a9e5 teach the dss chunk allocator to handle new_addr
This provides in-place expansion of huge allocations when the end of the
allocation is at the end of the sbrk heap. There's already the ability
to extend in-place via recycled chunks but this handles the initial
growth of the heap via repeated vector / string reallocations.

A possible future extension could allow realloc to go from the following:

    | huge allocation | recycled chunks |
                                        ^ dss_end

To a larger allocation built from recycled *and* new chunks:

    |                      huge allocation                      |
                                                                ^ dss_end

Doing that would involve teaching the chunk recycling code to request
new chunks to satisfy the request. The chunk_dss code wouldn't require
any further changes.

    #include <stdlib.h>

    int main(void) {
        size_t chunk = 4 * 1024 * 1024;
        void *ptr = NULL;
        for (size_t size = chunk; size < chunk * 128; size *= 2) {
            ptr = realloc(ptr, size);
            if (!ptr) return 1;
        }
    }

dss:secondary: 0.083s
dss:primary: 0.083s

After:

dss:secondary: 0.083s
dss:primary: 0.003s

The dss heap grows in the upwards direction, so the oldest chunks are at
the low addresses and they are used first. Linux prefers to grow the
mmap heap downwards, so the trick will not work in the *current* mmap
chunk allocator as a huge allocation will only be at the top of the heap
in a contrived case.
2014-11-28 16:11:19 -08:00
Jason Evans
551ebc4364 Convert to uniform style: cond == false --> !cond 2014-10-03 10:16:09 -07:00
Jason Evans
bd87b01999 Optimize Valgrind integration.
Forcefully disable tcache if running inside Valgrind, and remove
Valgrind calls in tcache-specific code.

Restructure Valgrind-related code to move most Valgrind calls out of the
fast path functions.

Take advantage of static knowledge to elide some branches in
JEMALLOC_VALGRIND_REALLOC().
2014-04-15 16:49:57 -07:00
Jason Evans
4d434adb14 Make dss non-optional, and fix an "arena.<i>.dss" mallctl bug.
Make dss non-optional on all platforms which support sbrk(2).

Fix the "arena.<i>.dss" mallctl to return an error if "primary" or
"secondary" precedence is specified, but sbrk(2) is not supported.
2014-04-15 12:09:48 -07:00
Jason Evans
6668853596 Avoid deprecated sbrk(2) on OS X.
Avoid referencing sbrk(2) on OS X, because it is deprecated as of OS X
10.9 (Mavericks), and the compiler warns against using it.
2013-12-03 21:49:36 -08:00
Jason Evans
06912756cc Fix Valgrind integration.
Fix Valgrind integration to annotate all internally allocated memory in
a way that keeps Valgrind happy about internal data structure access.
2013-01-31 17:02:53 -08:00
Jason Evans
38067483c5 Tighten valgrind integration.
Tighten valgrind integration such that immediately after memory is
validated or zeroed, valgrind is told to forget the memory's 'defined'
state.  The only place newly allocated memory should be left marked as
'defined' is in the public functions (e.g. calloc() and realloc()).
2013-01-21 20:04:42 -08:00
Jason Evans
609ae595f0 Add arena-specific and selective dss allocation.
Add the "arenas.extend" mallctl, so that it is possible to create new
arenas that are outside the set that jemalloc automatically multiplexes
threads onto.

Add the ALLOCM_ARENA() flag for {,r,d}allocm(), so that it is possible
to explicitly allocate from a particular arena.

Add the "opt.dss" mallctl, which controls the default precedence of dss
allocation relative to mmap allocation.

Add the "arena.<i>.dss" mallctl, which makes it possible to set the
default dss precedence on a per arena or global basis.

Add the "arena.<i>.purge" mallctl, which obsoletes "arenas.purge".

Add the "stats.arenas.<i>.dss" mallctl.
2012-10-12 18:26:16 -07:00
Jason Evans
7ad54c1c30 Fix chunk allocation/deallocation bugs.
Fix chunk_alloc_dss() to zero memory when requested.

Fix chunk_dealloc() to avoid chunk_dealloc_mmap() for dss-allocated
memory.

Fix huge_palloc() to always junk fill when requested.

Improve chunk_recycle() to report that memory is zeroed as a side effect
of pages_purge().
2012-04-21 16:04:51 -07:00
Jason Evans
8f0e0eb1c0 Fix a memory corruption bug in chunk_alloc_dss().
Fix a memory corruption bug in chunk_alloc_dss() that was due to
claiming newly allocated memory is zeroed.

Reverse order of preference between mmap() and sbrk() to prefer mmap().

Clean up management of 'zero' parameter in chunk_alloc*().
2012-04-21 13:33:48 -07:00
Jason Evans
7ca0fdfb85 Disable munmap() if it causes VM map holes.
Add a configure test to determine whether common mmap()/munmap()
patterns cause VM map holes, and only use munmap() to discard unused
chunks if the problem does not exist.

Unify the chunk caching for mmap and dss.

Fix options processing to limit lg_chunk to be large enough that
redzones will always fit.
2012-04-12 20:20:58 -07:00
Mike Hommey
83c324acd8 Use a stub replacement and disable dss when sbrk is not supported 2012-04-12 08:43:08 -07:00
Jason Evans
5ff709c264 Normalize aligned allocation algorithms.
Normalize arena_palloc(), chunk_alloc_mmap_slow(), and
chunk_recycle_dss() to use the same algorithm for trimming
over-allocation.

Add the ALIGNMENT_ADDR2BASE(), ALIGNMENT_ADDR2OFFSET(), and
ALIGNMENT_CEILING() macros, and use them where appropriate.

Remove the run_size_p parameter from sa2u().

Fix a potential deadlock in chunk_recycle_dss() that was introduced by
eae269036c (Add alignment support to
chunk_alloc()).
2012-04-11 18:13:45 -07:00
Jason Evans
a1ee7838e1 Rename labels.
Rename labels from FOO to label_foo in order to avoid system macro
definitions, in particular OUT and ERROR on mingw.

Reported by Mike Hommey.
2012-04-10 15:07:44 -07:00
Mike Hommey
eae269036c Add alignment support to chunk_alloc(). 2012-04-10 14:51:39 -07:00
Jason Evans
4e2e3dd9cf Fix fork-related bugs.
Acquire/release arena bin locks as part of the prefork/postfork.  This
bug made deadlock in the child between fork and exec a possibility.

Split jemalloc_postfork() into jemalloc_postfork_{parent,child}() so
that the child can reinitialize mutexes rather than unlocking them.  In
practice, this bug tended not to cause problems.
2012-03-13 16:31:41 -07:00
Jason Evans
7372b15a31 Reduce cpp conditional logic complexity.
Convert configuration-related cpp conditional logic to use static
constant variables, e.g.:

  #ifdef JEMALLOC_DEBUG
    [...]
  #endif

becomes:

  if (config_debug) {
    [...]
  }

The advantage is clearer, more concise code.  The main disadvantage is
that data structures no longer have conditionally defined fields, so
they pay the cost of all fields regardless of whether they are used.  In
practice, this is only a minor concern; config_stats will go away in an
upcoming change, and config_prof is the only other major feature that
depends on more than a few special-purpose fields.
2012-02-10 20:22:09 -08:00
Jason Evans
7427525c28 Move repo contents in jemalloc/ to top level. 2011-03-31 20:36:17 -07:00