diff options
Diffstat (limited to 'deps/jemalloc/include/jemalloc/internal/bitmap.h')
| -rw-r--r-- | deps/jemalloc/include/jemalloc/internal/bitmap.h | 76 |
1 files changed, 60 insertions, 16 deletions
diff --git a/deps/jemalloc/include/jemalloc/internal/bitmap.h b/deps/jemalloc/include/jemalloc/internal/bitmap.h index fcc6005c7..36f38b59c 100644 --- a/deps/jemalloc/include/jemalloc/internal/bitmap.h +++ b/deps/jemalloc/include/jemalloc/internal/bitmap.h @@ -15,6 +15,15 @@ typedef unsigned long bitmap_t; #define BITMAP_GROUP_NBITS (ZU(1) << LG_BITMAP_GROUP_NBITS) #define BITMAP_GROUP_NBITS_MASK (BITMAP_GROUP_NBITS-1) +/* + * Do some analysis on how big the bitmap is before we use a tree. For a brute + * force linear search, if we would have to call ffs_lu() more than 2^3 times, + * use a tree instead. + */ +#if LG_BITMAP_MAXBITS - LG_BITMAP_GROUP_NBITS > 3 +# define USE_TREE +#endif + /* Number of groups required to store a given number of bits. */ #define BITMAP_BITS2GROUPS(nbits) \ ((nbits + BITMAP_GROUP_NBITS_MASK) >> LG_BITMAP_GROUP_NBITS) @@ -48,6 +57,8 @@ typedef unsigned long bitmap_t; /* * Maximum number of groups required to support LG_BITMAP_MAXBITS. */ +#ifdef USE_TREE + #if LG_BITMAP_MAXBITS <= LG_BITMAP_GROUP_NBITS # define BITMAP_GROUPS_MAX BITMAP_GROUPS_1_LEVEL(BITMAP_MAXBITS) #elif LG_BITMAP_MAXBITS <= LG_BITMAP_GROUP_NBITS * 2 @@ -65,6 +76,12 @@ typedef unsigned long bitmap_t; (LG_BITMAP_MAXBITS / LG_SIZEOF_BITMAP) \ + !!(LG_BITMAP_MAXBITS % LG_SIZEOF_BITMAP) +#else /* USE_TREE */ + +#define BITMAP_GROUPS_MAX BITMAP_BITS2GROUPS(BITMAP_MAXBITS) + +#endif /* USE_TREE */ + #endif /* JEMALLOC_H_TYPES */ /******************************************************************************/ #ifdef JEMALLOC_H_STRUCTS @@ -78,6 +95,7 @@ struct bitmap_info_s { /* Logical number of bits in bitmap (stored at bottom level). */ size_t nbits; +#ifdef USE_TREE /* Number of levels necessary for nbits. */ unsigned nlevels; @@ -86,6 +104,10 @@ struct bitmap_info_s { * bottom to top (e.g. the bottom level is stored in levels[0]). */ bitmap_level_t levels[BITMAP_MAX_LEVELS+1]; +#else /* USE_TREE */ + /* Number of groups necessary for nbits. */ + size_t ngroups; +#endif /* USE_TREE */ }; #endif /* JEMALLOC_H_STRUCTS */ @@ -93,9 +115,8 @@ struct bitmap_info_s { #ifdef JEMALLOC_H_EXTERNS void bitmap_info_init(bitmap_info_t *binfo, size_t nbits); -size_t bitmap_info_ngroups(const bitmap_info_t *binfo); -size_t bitmap_size(size_t nbits); void bitmap_init(bitmap_t *bitmap, const bitmap_info_t *binfo); +size_t bitmap_size(const bitmap_info_t *binfo); #endif /* JEMALLOC_H_EXTERNS */ /******************************************************************************/ @@ -113,10 +134,20 @@ void bitmap_unset(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit); JEMALLOC_INLINE bool bitmap_full(bitmap_t *bitmap, const bitmap_info_t *binfo) { - unsigned rgoff = binfo->levels[binfo->nlevels].group_offset - 1; +#ifdef USE_TREE + size_t rgoff = binfo->levels[binfo->nlevels].group_offset - 1; bitmap_t rg = bitmap[rgoff]; /* The bitmap is full iff the root group is 0. */ return (rg == 0); +#else + size_t i; + + for (i = 0; i < binfo->ngroups; i++) { + if (bitmap[i] != 0) + return (false); + } + return (true); +#endif } JEMALLOC_INLINE bool @@ -128,7 +159,7 @@ bitmap_get(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) assert(bit < binfo->nbits); goff = bit >> LG_BITMAP_GROUP_NBITS; g = bitmap[goff]; - return (!(g & (1LU << (bit & BITMAP_GROUP_NBITS_MASK)))); + return (!(g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK)))); } JEMALLOC_INLINE void @@ -143,10 +174,11 @@ bitmap_set(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) goff = bit >> LG_BITMAP_GROUP_NBITS; gp = &bitmap[goff]; g = *gp; - assert(g & (1LU << (bit & BITMAP_GROUP_NBITS_MASK))); - g ^= 1LU << (bit & BITMAP_GROUP_NBITS_MASK); + assert(g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK))); + g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK); *gp = g; assert(bitmap_get(bitmap, binfo, bit)); +#ifdef USE_TREE /* Propagate group state transitions up the tree. */ if (g == 0) { unsigned i; @@ -155,13 +187,14 @@ bitmap_set(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) goff = bit >> LG_BITMAP_GROUP_NBITS; gp = &bitmap[binfo->levels[i].group_offset + goff]; g = *gp; - assert(g & (1LU << (bit & BITMAP_GROUP_NBITS_MASK))); - g ^= 1LU << (bit & BITMAP_GROUP_NBITS_MASK); + assert(g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK))); + g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK); *gp = g; if (g != 0) break; } } +#endif } /* sfu: set first unset. */ @@ -174,15 +207,24 @@ bitmap_sfu(bitmap_t *bitmap, const bitmap_info_t *binfo) assert(!bitmap_full(bitmap, binfo)); +#ifdef USE_TREE i = binfo->nlevels - 1; g = bitmap[binfo->levels[i].group_offset]; - bit = jemalloc_ffsl(g) - 1; + bit = ffs_lu(g) - 1; while (i > 0) { i--; g = bitmap[binfo->levels[i].group_offset + bit]; - bit = (bit << LG_BITMAP_GROUP_NBITS) + (jemalloc_ffsl(g) - 1); + bit = (bit << LG_BITMAP_GROUP_NBITS) + (ffs_lu(g) - 1); } - +#else + i = 0; + g = bitmap[0]; + while ((bit = ffs_lu(g)) == 0) { + i++; + g = bitmap[i]; + } + bit = (i << LG_BITMAP_GROUP_NBITS) + (bit - 1); +#endif bitmap_set(bitmap, binfo, bit); return (bit); } @@ -193,7 +235,7 @@ bitmap_unset(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) size_t goff; bitmap_t *gp; bitmap_t g; - bool propagate; + UNUSED bool propagate; assert(bit < binfo->nbits); assert(bitmap_get(bitmap, binfo, bit)); @@ -201,10 +243,11 @@ bitmap_unset(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) gp = &bitmap[goff]; g = *gp; propagate = (g == 0); - assert((g & (1LU << (bit & BITMAP_GROUP_NBITS_MASK))) == 0); - g ^= 1LU << (bit & BITMAP_GROUP_NBITS_MASK); + assert((g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK))) == 0); + g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK); *gp = g; assert(!bitmap_get(bitmap, binfo, bit)); +#ifdef USE_TREE /* Propagate group state transitions up the tree. */ if (propagate) { unsigned i; @@ -214,14 +257,15 @@ bitmap_unset(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) gp = &bitmap[binfo->levels[i].group_offset + goff]; g = *gp; propagate = (g == 0); - assert((g & (1LU << (bit & BITMAP_GROUP_NBITS_MASK))) + assert((g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK))) == 0); - g ^= 1LU << (bit & BITMAP_GROUP_NBITS_MASK); + g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK); *gp = g; if (!propagate) break; } } +#endif /* USE_TREE */ } #endif |