From b07f01c20f5c01f8a6b5a60e760aad3381e1ff9a Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Fri, 9 Nov 2012 16:37:28 +0100 Subject: erts: Save one word per block for thread preferred allocators by making use of the new block header scheme to find the carrier header and thereby the allocator. --- erts/emulator/beam/erl_alloc_util.c | 178 ++++++++++++------------------------ 1 file changed, 61 insertions(+), 117 deletions(-) (limited to 'erts/emulator/beam/erl_alloc_util.c') diff --git a/erts/emulator/beam/erl_alloc_util.c b/erts/emulator/beam/erl_alloc_util.c index b3c948c3e0..d1335598b0 100644 --- a/erts/emulator/beam/erl_alloc_util.c +++ b/erts/emulator/beam/erl_alloc_util.c @@ -258,6 +258,11 @@ static Uint max_mseg_carriers; /* Carriers ... */ +#define SIZEOF_SBC_HDR (UNIT_CEILING(sizeof(Carrier_t) \ + + FBLK_FTR_SZ \ + + ABLK_HDR_SZ) \ + - ABLK_HDR_SZ) + #define MSEG_CARRIER_HDR_FLAG (((UWord) 1) << 0) #define SBC_CARRIER_HDR_FLAG (((UWord) 1) << 1) @@ -266,11 +271,11 @@ static Uint max_mseg_carriers; #define SCH_MBC 0 #define SCH_SBC SBC_CARRIER_HDR_FLAG -#define SET_CARRIER_HDR(C, Sz, F) \ - (ASSERT(((Sz) & FLG_MASK) == 0), (C)->chdr = ((Sz) | (F))) +#define SET_CARRIER_HDR(C, Sz, F, AP) \ + (ASSERT(((Sz) & FLG_MASK) == 0), (C)->chdr = ((Sz) | (F)), (C)->allctr = (AP)) -#define BLK2SBC(AP, B) \ - ((Carrier_t *) (((char *) (B)) - (AP)->sbc_header_size)) +#define BLK2SBC(B) \ + ((Carrier_t *) (((char *) (B)) - SIZEOF_SBC_HDR)) #define FBLK2MBC(AP, B) \ ((Carrier_t *) (((char *) (B)) - (AP)->mbc_header_size)) @@ -796,13 +801,9 @@ erts_alcu_fix_alloc_shrink(Allctr_t *allctr, erts_aint32_t flgs) #define ERTS_ALCU_DD_FIX_TYPE_OFFS \ ((sizeof(ErtsAllctrDDBlock_t)-1)/sizeof(UWord) + 1) -#define ERTS_AU_PREF_ALLOC_IX_MASK \ - ((((UWord) 1) << ERTS_AU_PREF_ALLOC_BITS) - 1) -#define ERTS_AU_PREF_ALLOC_SIZE_MASK \ - ((((UWord) 1) << (sizeof(UWord)*8 - ERTS_AU_PREF_ALLOC_BITS)) - 1) -static ERTS_INLINE int -get_pref_allctr(void *extra, Allctr_t **allctr) +static ERTS_INLINE Allctr_t* +get_pref_allctr(void *extra) { ErtsAllocatorThrSpec_t *tspec = (ErtsAllocatorThrSpec_t *) extra; int pref_ix; @@ -812,34 +813,26 @@ get_pref_allctr(void *extra, Allctr_t **allctr) ASSERT(sizeof(UWord) == sizeof(Allctr_t *)); ASSERT(0 <= pref_ix && pref_ix < tspec->size); - *allctr = tspec->allctr[pref_ix]; - return pref_ix; + return tspec->allctr[pref_ix]; } -static ERTS_INLINE void * -get_used_allctr(void *extra, void *p, Allctr_t **allctr, UWord *sizep) +/* SMP note: + * get_used_allctr() must be safe WITHOUT locking the allocator while + * concurrent threads may be updating adjacent blocks. + * We rely on getting a consistent result (without atomic op) when reading + * the block header word even if a concurrent thread is updating + * the "PREV_FREE" flag bit. + */ +static ERTS_INLINE Allctr_t* +get_used_allctr(void *extra, void *p, UWord *sizep) { - ErtsAllocatorThrSpec_t *tspec = (ErtsAllocatorThrSpec_t *) extra; - void *ptr = (void *) (((char *) p) - sizeof(UWord)); - UWord ainfo = *((UWord *) ptr); - int aix = (int) (ainfo & ERTS_AU_PREF_ALLOC_IX_MASK); - *allctr = tspec->allctr[aix]; - if (sizep) - *sizep = ((ainfo >> ERTS_AU_PREF_ALLOC_BITS) - & ERTS_AU_PREF_ALLOC_SIZE_MASK); - return ptr; -} + Block_t* blk = UMEM2BLK(p); + Carrier_t* crr = IS_SBC_BLK(blk) ? BLK2SBC(blk) : BLK2MBC(blk); -static ERTS_INLINE void * -put_used_allctr(void *p, int ix, UWord size) -{ - UWord ainfo = (size >= ERTS_AU_PREF_ALLOC_SIZE_MASK - ? ERTS_AU_PREF_ALLOC_SIZE_MASK - : size); - ainfo <<= ERTS_AU_PREF_ALLOC_BITS; - ainfo |= (UWord) ix; - *((UWord *) p) = ainfo; - return (void *) (((char *) p) + sizeof(UWord)); + if (sizep) { + *sizep = BLK_UMEM_SZ(blk); + } + return crr->allctr; } static void @@ -1895,7 +1888,7 @@ create_sbmbc(Allctr_t *allctr, Uint umem_sz) crr = erts_alloc(ERTS_ALC_T_SBMBC, crr_sz); INC_CC(allctr->calls.sbmbc_alloc); - SET_CARRIER_HDR(crr, crr_sz, SCH_SYS_ALLOC|SCH_MBC); + SET_CARRIER_HDR(crr, crr_sz, SCH_SYS_ALLOC|SCH_MBC, allctr); blk = MBC2FBLK(allctr, crr); @@ -2030,12 +2023,12 @@ create_carrier(Allctr_t *allctr, Uint umem_sz, UWord flags) is_mseg = 1; #endif if (flags & CFLG_SBC) { - SET_CARRIER_HDR(crr, crr_sz, SCH_MSEG|SCH_SBC); + SET_CARRIER_HDR(crr, crr_sz, SCH_MSEG|SCH_SBC, allctr); STAT_MSEG_SBC_ALLOC(allctr, crr_sz, blk_sz); goto sbc_final_touch; } else { - SET_CARRIER_HDR(crr, crr_sz, SCH_MSEG|SCH_MBC); + SET_CARRIER_HDR(crr, crr_sz, SCH_MSEG|SCH_MBC, allctr); STAT_MSEG_MBC_ALLOC(allctr, crr_sz); goto mbc_final_touch; } @@ -2075,7 +2068,7 @@ create_carrier(Allctr_t *allctr, Uint umem_sz, UWord flags) } } if (flags & CFLG_SBC) { - SET_CARRIER_HDR(crr, crr_sz, SCH_SYS_ALLOC|SCH_SBC); + SET_CARRIER_HDR(crr, crr_sz, SCH_SYS_ALLOC|SCH_SBC, allctr); STAT_SYS_ALLOC_SBC_ALLOC(allctr, crr_sz, blk_sz); #if HAVE_ERTS_MSEG @@ -2093,7 +2086,7 @@ create_carrier(Allctr_t *allctr, Uint umem_sz, UWord flags) } else { - SET_CARRIER_HDR(crr, crr_sz, SCH_SYS_ALLOC|SCH_MBC); + SET_CARRIER_HDR(crr, crr_sz, SCH_SYS_ALLOC|SCH_MBC, allctr); STAT_SYS_ALLOC_MBC_ALLOC(allctr, crr_sz); #if HAVE_ERTS_MSEG @@ -2144,7 +2137,7 @@ resize_carrier(Allctr_t *allctr, Block_t *old_blk, Uint umem_sz, UWord flags) HARD_CHECK_BLK_CARRIER(allctr, old_blk); old_blk_sz = SBC_BLK_SZ(old_blk); - old_crr = BLK2SBC(allctr, old_blk); + old_crr = BLK2SBC(old_blk); old_crr_sz = CARRIER_SZ(old_crr); ASSERT(IS_SB_CARRIER(old_crr)); ASSERT(IS_SBC_BLK(old_blk)); @@ -2270,7 +2263,7 @@ destroy_carrier(Allctr_t *allctr, Block_t *blk) if (IS_SBC_BLK(blk)) { Uint blk_sz = SBC_BLK_SZ(blk); - crr = BLK2SBC(allctr, blk); + crr = BLK2SBC(blk); crr_sz = CARRIER_SZ(crr); ASSERT(IS_LAST_BLK(blk)); @@ -3506,24 +3499,20 @@ erts_alcu_alloc_thr_spec(ErtsAlcType_t type, void *extra, Uint size) void * erts_alcu_alloc_thr_pref(ErtsAlcType_t type, void *extra, Uint size) { - int pref_ix; Allctr_t *pref_allctr; void *res; - pref_ix = get_pref_allctr(extra, &pref_allctr); + pref_allctr = get_pref_allctr(extra); if (pref_allctr->thread_safe) erts_mtx_lock(&pref_allctr->mutex); ERTS_ALCU_DBG_CHK_THR_ACCESS(pref_allctr); - res = do_erts_alcu_alloc(type, pref_allctr, size + sizeof(UWord)); + res = do_erts_alcu_alloc(type, pref_allctr, size); if (pref_allctr->thread_safe) erts_mtx_unlock(&pref_allctr->mutex); - if (res) - res = put_used_allctr(res, pref_ix, size); - DEBUG_CHECK_ALIGNMENT(res); @@ -3644,21 +3633,20 @@ erts_alcu_free_thr_pref(ErtsAlcType_t type, void *extra, void *p) { if (p) { Allctr_t *pref_allctr, *used_allctr; - void *ptr; - get_pref_allctr(extra, &pref_allctr); - ptr = get_used_allctr(extra, p, &used_allctr, NULL); + pref_allctr = get_pref_allctr(extra); + used_allctr = get_used_allctr(extra, p, NULL); if (pref_allctr != used_allctr) enqueue_dealloc_other_instance(type, used_allctr, - ptr, + p, (used_allctr->dd.ix - pref_allctr->dd.ix)); else { if (used_allctr->thread_safe) erts_mtx_lock(&used_allctr->mutex); ERTS_ALCU_DBG_CHK_THR_ACCESS(used_allctr); - do_erts_alcu_free(type, used_allctr, ptr); + do_erts_alcu_free(type, used_allctr, p); if (used_allctr->thread_safe) erts_mtx_unlock(&used_allctr->mutex); } @@ -3745,7 +3733,7 @@ do_erts_alcu_realloc(ErtsAlcType_t type, Uint crr_sz_val; #if HAVE_ERTS_MSEG - if (IS_SYS_ALLOC_CARRIER(BLK2SBC(allctr, blk))) + if (IS_SYS_ALLOC_CARRIER(BLK2SBC(blk))) #endif crr_sz = SYS_ALLOC_CARRIER_CEILING(used_sz); #if HAVE_ERTS_MSEG @@ -3962,16 +3950,15 @@ static ERTS_INLINE void * realloc_thr_pref(ErtsAlcType_t type, void *extra, void *p, Uint size, int force_move) { - int pref_ix; - void *ptr, *res; + void *res; Allctr_t *pref_allctr, *used_allctr; UWord old_user_size; if (!p) return erts_alcu_alloc_thr_pref(type, extra, size); - pref_ix = get_pref_allctr(extra, &pref_allctr); - ptr = get_used_allctr(extra, p, &used_allctr, &old_user_size); + pref_allctr = get_pref_allctr(extra); + used_allctr = get_used_allctr(extra, p, &old_user_size); ASSERT(used_allctr && pref_allctr); @@ -3981,56 +3968,33 @@ realloc_thr_pref(ErtsAlcType_t type, void *extra, void *p, Uint size, ERTS_ALCU_DBG_CHK_THR_ACCESS(used_allctr); res = do_erts_alcu_realloc(type, used_allctr, - ptr, - size + sizeof(UWord), + p, + size, 0); if (used_allctr->thread_safe) erts_mtx_unlock(&used_allctr->mutex); - if (res) - res = put_used_allctr(res, pref_ix, size); } else { if (pref_allctr->thread_safe) erts_mtx_lock(&pref_allctr->mutex); - res = do_erts_alcu_alloc(type, pref_allctr, size + sizeof(UWord)); - if (pref_allctr->thread_safe && (!force_move - || used_allctr != pref_allctr)) + res = do_erts_alcu_alloc(type, pref_allctr, size); + if (pref_allctr->thread_safe && used_allctr != pref_allctr) { erts_mtx_unlock(&pref_allctr->mutex); + } if (res) { - Block_t *blk; - size_t cpy_size; - - res = put_used_allctr(res, pref_ix, size); - DEBUG_CHECK_ALIGNMENT(res); - blk = UMEM2BLK(ptr); - if (old_user_size != ERTS_AU_PREF_ALLOC_SIZE_MASK) - cpy_size = old_user_size; - else { - if (used_allctr->thread_safe && (!force_move - || used_allctr != pref_allctr)) - erts_mtx_lock(&used_allctr->mutex); - ERTS_SMP_LC_ASSERT(!used_allctr->thread_safe || - erts_lc_mtx_is_locked(&used_allctr->mutex)); - cpy_size = BLK_SZ(blk); - if (used_allctr->thread_safe && (!force_move - || used_allctr != pref_allctr)) - erts_mtx_unlock(&used_allctr->mutex); - cpy_size -= ABLK_HDR_SZ + sizeof(UWord); - } - if (cpy_size > size) - cpy_size = size; - sys_memcpy(res, p, cpy_size); + sys_memcpy(res, p, MIN(size,old_user_size)); - if (!force_move || used_allctr != pref_allctr) + if (used_allctr != pref_allctr) { enqueue_dealloc_other_instance(type, used_allctr, - ptr, + p, (used_allctr->dd.ix - pref_allctr->dd.ix)); + } else { - do_erts_alcu_free(type, used_allctr, ptr); + do_erts_alcu_free(type, used_allctr, p); ASSERT(pref_allctr == used_allctr); if (pref_allctr->thread_safe) erts_mtx_unlock(&pref_allctr->mutex); @@ -4208,35 +4172,16 @@ erts_alcu_start(Allctr_t *allctr, AllctrInit_t *init) #ifdef ERTS_SMP allctr->dd.use = 0; if (init->tpref) { - allctr->mbc_header_size = (UNIT_CEILING(allctr->mbc_header_size - + FBLK_FTR_SZ - + ABLK_HDR_SZ - + sizeof(UWord)) - - ABLK_HDR_SZ - - sizeof(UWord)); - allctr->sbc_header_size = (UNIT_CEILING(sizeof(Carrier_t) - + FBLK_FTR_SZ - + ABLK_HDR_SZ - + sizeof(UWord)) - - ABLK_HDR_SZ - - sizeof(UWord)); - allctr->dd.use = 1; init_dd_queue(&allctr->dd.q); allctr->dd.ix = init->ix; } - else #endif - { - allctr->mbc_header_size = (UNIT_CEILING(allctr->mbc_header_size - + FBLK_FTR_SZ - + ABLK_HDR_SZ) - - ABLK_HDR_SZ); - allctr->sbc_header_size = (UNIT_CEILING(sizeof(Carrier_t) - + FBLK_FTR_SZ - + ABLK_HDR_SZ) - - ABLK_HDR_SZ); - } + allctr->mbc_header_size = (UNIT_CEILING(allctr->mbc_header_size + + FBLK_FTR_SZ + + ABLK_HDR_SZ) + - ABLK_HDR_SZ); + allctr->sbc_header_size = SIZEOF_SBC_HDR; if (allctr->main_carrier_size) { Block_t *blk; @@ -4362,8 +4307,7 @@ erts_alcu_test(unsigned long op, unsigned long a1, unsigned long a2) case 0x00b: return (unsigned long) CARRIER_SZ((Carrier_t *) a1); case 0x00c: return (unsigned long) SBC2BLK((Allctr_t *) a1, (Carrier_t *) a2); - case 0x00d: return (unsigned long) BLK2SBC((Allctr_t *) a1, - (Block_t *) a2); + case 0x00d: return (unsigned long) BLK2SBC((Block_t *) a2); case 0x00e: return (unsigned long) MBC2FBLK((Allctr_t *) a1, (Carrier_t *) a2); case 0x00f: return (unsigned long) FBLK2MBC((Allctr_t *) a1, @@ -4438,7 +4382,7 @@ check_blk_carrier(Allctr_t *allctr, Block_t *iblk) CarrierList_t *cl; if (IS_SBC_BLK(iblk)) { - Carrier_t *sbc = BLK2SBC(allctr, iblk); + Carrier_t *sbc = BLK2SBC(iblk); ASSERT(SBC2BLK(allctr, sbc) == iblk); ASSERT(CARRIER_SZ(sbc) - allctr->sbc_header_size >= SBC_BLK_SZ(iblk)); -- cgit v1.2.3