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server-skynet-source-3rd-je.../src/bitmap.c

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Normalize #define whitespace. Consistently use a tab rather than a space following #define.
2013-12-09 14:28:27 +08:00
#define JEMALLOC_BITMAP_C_
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
#include "jemalloc/internal/jemalloc_internal.h"
/******************************************************************************/
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
#ifdef USE_TREE
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
void
bitmap_info_init(bitmap_info_t *binfo, size_t nbits)
{
unsigned i;
size_t group_count;
assert(nbits > 0);
assert(nbits <= (ZU(1) << LG_BITMAP_MAXBITS));
/*
* Compute the number of groups necessary to store nbits bits, and
* progressively work upward through the levels until reaching a level
* that requires only one group.
*/
binfo->levels[0].group_offset = 0;
Implement compile-time bitmap size computation.
2014-09-29 05:43:11 +08:00
group_count = BITMAP_BITS2GROUPS(nbits);
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
for (i = 1; group_count > 1; i++) {
assert(i < BITMAP_MAX_LEVELS);
binfo->levels[i].group_offset = binfo->levels[i-1].group_offset
+ group_count;
Implement compile-time bitmap size computation.
2014-09-29 05:43:11 +08:00
group_count = BITMAP_BITS2GROUPS(group_count);
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
}
binfo->levels[i].group_offset = binfo->levels[i-1].group_offset
+ group_count;
Implement compile-time bitmap size computation.
2014-09-29 05:43:11 +08:00
assert(binfo->levels[i].group_offset <= BITMAP_GROUPS_MAX);
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
binfo->nlevels = i;
binfo->nbits = nbits;
}
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
static size_t
bitmap_info_ngroups(const bitmap_info_t *binfo)
{
return (binfo->levels[binfo->nlevels].group_offset);
}
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
void
bitmap_init(bitmap_t *bitmap, const bitmap_info_t *binfo)
{
size_t extra;
unsigned i;
/*
* Bits are actually inverted with regard to the external bitmap
* interface, so the bitmap starts out with all 1 bits, except for
* trailing unused bits (if any). Note that each group uses bit 0 to
* correspond to the first logical bit in the group, so extra bits
* are the most significant bits of the last group.
*/
Miscellaneous bitmap refactoring.
2016-02-27 05:59:41 +08:00
memset(bitmap, 0xffU, bitmap_size(binfo));
Use bitmaps to track small regions. The previous free list implementation, which embedded singly linked lists in available regions, had the unfortunate side effect of causing many cache misses during thread cache fills. Fix this in two places: - arena_run_t: Use a new bitmap implementation to track which regions are available. Furthermore, revert to preferring the lowest available region (as jemalloc did with its old bitmap-based approach). - tcache_t: Move read-only tcache_bin_t metadata into tcache_bin_info_t, and add a contiguous array of pointers to tcache_t in order to track cached objects. This substantially increases the size of tcache_t, but results in much higher data locality for common tcache operations. As a side benefit, it is again possible to efficiently flush the least recently used cached objects, so this change changes flushing from MRU to LRU. The new bitmap implementation uses a multi-level summary approach to make finding the lowest available region very fast. In practice, bitmaps only have one or two levels, though the implementation is general enough to handle extremely large bitmaps, mainly so that large page sizes can still be entertained. Fix tcache_bin_flush_large() to always flush statistics, in the same way that tcache_bin_flush_small() was recently fixed. Use JEMALLOC_DEBUG rather than NDEBUG. Add dassert(), and use it for debug-only asserts.
2011-03-17 01:30:13 +08:00
extra = (BITMAP_GROUP_NBITS - (binfo->nbits & BITMAP_GROUP_NBITS_MASK))
& BITMAP_GROUP_NBITS_MASK;
if (extra != 0)
bitmap[binfo->levels[1].group_offset - 1] >>= extra;
for (i = 1; i < binfo->nlevels; i++) {
size_t group_count = binfo->levels[i].group_offset -
binfo->levels[i-1].group_offset;
extra = (BITMAP_GROUP_NBITS - (group_count &
BITMAP_GROUP_NBITS_MASK)) & BITMAP_GROUP_NBITS_MASK;
if (extra != 0)
bitmap[binfo->levels[i+1].group_offset - 1] >>= extra;
}
}
Miscellaneous bitmap refactoring.
2016-02-27 05:59:41 +08:00
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
#else /* USE_TREE */
void
bitmap_info_init(bitmap_info_t *binfo, size_t nbits)
{
assert(nbits > 0);
assert(nbits <= (ZU(1) << LG_BITMAP_MAXBITS));
Reduce differences between alternative bitmap implementations.
2016-04-07 01:38:47 +08:00
binfo->ngroups = BITMAP_BITS2GROUPS(nbits);
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
binfo->nbits = nbits;
}
Miscellaneous bitmap refactoring.
2016-02-27 05:59:41 +08:00
static size_t
bitmap_info_ngroups(const bitmap_info_t *binfo)
{
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
return (binfo->ngroups);
Miscellaneous bitmap refactoring.
2016-02-27 05:59:41 +08:00
}
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
void
bitmap_init(bitmap_t *bitmap, const bitmap_info_t *binfo)
{
size_t extra;
memset(bitmap, 0xffU, bitmap_size(binfo));
Reduce differences between alternative bitmap implementations.
2016-04-07 01:38:47 +08:00
extra = (BITMAP_GROUP_NBITS - (binfo->nbits & BITMAP_GROUP_NBITS_MASK))
& BITMAP_GROUP_NBITS_MASK;
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
if (extra != 0)
Reduce differences between alternative bitmap implementations.
2016-04-07 01:38:47 +08:00
bitmap[binfo->ngroups - 1] >>= extra;
Use linear scan for small bitmaps For small bitmaps, a linear scan of the bitmap is slightly faster than a tree search - bitmap_t is more compact, and there are fewer writes since we don't have to propogate state transitions up the tree. On x86_64 with the current settings, I'm seeing ~.5%-1% CPU improvement in production canaries with this change. The old tree code is left since 32bit sizes are much larger (and ffsl smaller), and maybe the run sizes will change in the future. This resolves #339.
2016-02-25 00:04:43 +08:00
}
#endif /* USE_TREE */
Miscellaneous bitmap refactoring.
2016-02-27 05:59:41 +08:00
size_t
bitmap_size(const bitmap_info_t *binfo)
{
return (bitmap_info_ngroups(binfo) << LG_SIZEOF_BITMAP);
}
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