From 7e789df8dd9c7d86e9cc354521a37aa598aa5ec8 Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Wed, 31 Oct 2012 23:31:50 +0100 Subject: Improve configuration of process and port tables --- erts/emulator/beam/erl_ptab.c | 103 +++++++++++++++++++++++++----------------- 1 file changed, 62 insertions(+), 41 deletions(-) (limited to 'erts/emulator/beam/erl_ptab.c') diff --git a/erts/emulator/beam/erl_ptab.c b/erts/emulator/beam/erl_ptab.c index eba0c286cc..7ab756ae8d 100644 --- a/erts/emulator/beam/erl_ptab.c +++ b/erts/emulator/beam/erl_ptab.c @@ -429,7 +429,7 @@ erts_ptab_init_table(ErtsPTab *ptab, char *name) { size_t tab_sz; - int max_data_bits; + int bits; char *tab_end; erts_smp_atomic_t *tab_entry; erts_smp_rwmtx_opt_t rwmtx_opts = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER; @@ -440,8 +440,13 @@ erts_ptab_init_table(ErtsPTab *ptab, erts_smp_atomic32_init_nob(&ptab->vola.tile.count, 0); last_data_init_nob(ptab, ~((Uint64) 0)); - if (size > (1 << ERTS_PROC_BITS)) - size = 1 << ERTS_PROC_BITS; + /* A size that is a power of 2 is to prefer performance wise */ + bits = erts_fit_in_bits_int32(size-1); + size = 1 << bits; + if (size > ERTS_PTAB_MAX_SIZE) { + size = ERTS_PTAB_MAX_SIZE; + bits = erts_fit_in_bits_int32((Sint32) size - 1); + } ptab->r.o.max = size; @@ -454,34 +459,31 @@ erts_ptab_init_table(ErtsPTab *ptab, tab_entry++; } - max_data_bits = erts_fit_in_bits_int32((Sint32) ptab->r.o.max - 1); - ptab->r.o.tab_cache_lines = tab_sz/ERTS_CACHE_LINE_SIZE; ptab->r.o.pix_per_cache_line = (ERTS_CACHE_LINE_SIZE / sizeof(erts_smp_atomic_t)); - if ((ptab->r.o.max & (ptab->r.o.max - 1)) - | (ptab->r.o.pix_per_cache_line & (ptab->r.o.pix_per_cache_line - 1))) { - /* ptab->r.o.max or ptab->r.o.pix_per_cache_line not a power of 2 :-( */ - ptab->r.o.pix_cl_mask = 0; - ptab->r.o.pix_cl_shift = 0; - ptab->r.o.pix_cli_mask = 0; - ptab->r.o.pix_cli_shift = 0; - } - else { - ASSERT((ptab->r.o.tab_cache_lines - & (ptab->r.o.tab_cache_lines - 1)) == 0); - ptab->r.o.pix_cl_mask - = ptab->r.o.tab_cache_lines-1; - ptab->r.o.pix_cl_shift - = erts_fit_in_bits_int32(ptab->r.o.pix_per_cache_line-1); - ptab->r.o.pix_cli_shift - = erts_fit_in_bits_int32(ptab->r.o.pix_cl_mask); - ptab->r.o.pix_cli_mask - = (1 << (max_data_bits - ptab->r.o.pix_cli_shift)) - 1; - } + ASSERT((ptab->r.o.max & (ptab->r.o.max - 1)) == 0); /* power of 2 */ + ASSERT((ptab->r.o.pix_per_cache_line + & (ptab->r.o.pix_per_cache_line - 1)) == 0); /* power of 2 */ + ASSERT((ptab->r.o.tab_cache_lines + & (ptab->r.o.tab_cache_lines - 1)) == 0); /* power of 2 */ + + ptab->r.o.pix_mask + = (1 << bits) - 1; + ptab->r.o.pix_cl_mask + = ptab->r.o.tab_cache_lines-1; + ptab->r.o.pix_cl_shift + = erts_fit_in_bits_int32(ptab->r.o.pix_per_cache_line-1); + ptab->r.o.pix_cli_shift + = erts_fit_in_bits_int32(ptab->r.o.pix_cl_mask); + ptab->r.o.pix_cli_mask + = (1 << (bits - ptab->r.o.pix_cli_shift)) - 1; + + ASSERT(ptab->r.o.pix_cl_shift + ptab->r.o.pix_cli_shift == bits); ptab->r.o.invalid_element = invalid_element; - ptab->r.o.invalid_data = ERTS_PTAB_ID2DATA(invalid_element->id); + ptab->r.o.invalid_data = erts_ptab_id2data(ptab, invalid_element->id); + ptab->r.o.release_element = release_element; if (release_element) ptab->r.o.release_element = release_element; else @@ -493,6 +495,26 @@ erts_ptab_init_table(ErtsPTab *ptab, ptab->list.data.chunks = (((ptab->r.o.max - 1) / ERTS_PTAB_LIST_BIF_TAB_CHUNK_SIZE) + 1); + + if (size == ERTS_PTAB_MAX_SIZE) { + int pix; + /* + * We want a table size of a power of 2 which ERTS_PTAB_MAX_SIZE + * is. We only have ERTS_PTAB_MAX_SIZE-1 unique identifiers and + * we don't want to shrink the size to ERTS_PTAB_MAX_SIZE/2. + * + * In order to fix this, we insert a pointer from the table + * to the invalid_element, wich will be interpreted as a + * slot currently being modified. This way we will be able to + * have ERTS_PTAB_MAX_SIZE-1 valid elements in the table while + * still having a table size of the power of 2. + */ + erts_smp_atomic32_inc_nob(&ptab->vola.tile.count); + pix = erts_ptab_data2pix(ptab, ptab->r.o.invalid_data); + erts_smp_atomic_set_relb(&ptab->r.o.tab[pix], + (erts_aint_t) ptab->r.o.invalid_element); + } + } int @@ -541,7 +563,7 @@ erts_ptab_new_element(ErtsPTab *ptab, /* Reserve slot */ while (1) { ld++; - pix = erts_ptab_data2ix(ptab, ERTS_PTAB_LastData2EtermData(ld)); + pix = erts_ptab_data2pix(ptab, ERTS_PTAB_LastData2EtermData(ld)); if (erts_smp_atomic_read_nob(&ptab->r.o.tab[pix]) == ERTS_AINT_NULL) { erts_aint_t val; val = erts_smp_atomic_cmpxchg_relb(&ptab->r.o.tab[pix], @@ -558,8 +580,8 @@ erts_ptab_new_element(ErtsPTab *ptab, if (data == ptab->r.o.invalid_data) { /* Do not use invalid data; fix it... */ ld += ptab->r.o.max; - ASSERT(pix == erts_ptab_data2ix(ptab, - ERTS_PTAB_LastData2EtermData(ld))); + ASSERT(pix == erts_ptab_data2pix(ptab, + ERTS_PTAB_LastData2EtermData(ld))); data = ERTS_PTAB_LastData2EtermData(ld); ASSERT(data != ptab->r.o.invalid_data); } @@ -609,7 +631,7 @@ save_deleted_element(ErtsPTab *ptab, ErtsPTabElementCommon *ptab_el) ptdep->prev = ptab->list.data.deleted.end; ptdep->next = NULL; - ptdep->ix = erts_ptab_data2ix(ptab, ERTS_PTAB_ID2DATA(ptab_el->id)); + ptdep->ix = erts_ptab_id2pix(ptab, ptab_el->id); ptdep->u.element.id = ptab_el->id; ptdep->u.element.inserted = ptab_el->u.alive.started_interval; ptdep->u.element.deleted = @@ -632,7 +654,7 @@ erts_ptab_delete_element(ErtsPTab *ptab, ErtsPTabElementCommon *ptab_el) { int maybe_save; - int pix = erts_ptab_data2ix(ptab, ERTS_PTAB_ID2DATA(ptab_el->id)); + int pix = erts_ptab_id2pix(ptab, ptab_el->id); ASSERT(erts_get_scheduler_id()); /* *Need* to be a scheduler */ @@ -1274,9 +1296,9 @@ erts_ptab_test_next_id(ErtsPTab *ptab, int set, Uint next) data = ERTS_PTAB_LastData2EtermData(ld); if (ptab->r.o.invalid_data == data) { ld += ptab->r.o.max; - ASSERT(erts_ptab_data2ix(ptab, data) - == erts_ptab_data2ix(ptab, - ERTS_PTAB_LastData2EtermData(ld))); + ASSERT(erts_ptab_data2pix(ptab, data) + == erts_ptab_data2pix(ptab, + ERTS_PTAB_LastData2EtermData(ld))); } last_data_set_relb(ptab, ld); } @@ -1295,9 +1317,9 @@ erts_ptab_test_next_id(ErtsPTab *ptab, int set, Uint next) data = ERTS_PTAB_LastData2EtermData(ld); if (ptab->r.o.invalid_data == data) { ld += ptab->r.o.max; - ASSERT(erts_ptab_data2ix(ptab, data) - == erts_ptab_data2ix(ptab, - ERTS_PTAB_LastData2EtermData(ld))); + ASSERT(erts_ptab_data2pix(ptab, data) + == erts_ptab_data2pix(ptab, + ERTS_PTAB_LastData2EtermData(ld))); data = ERTS_PTAB_LastData2EtermData(ld); } res = data; @@ -1510,10 +1532,9 @@ debug_ptab_list_check_del_list(ErtsPTab *ptab) prev_x_interval_p = &ptdep->u.element.deleted; ERTS_PTAB_LIST_ASSERT( erts_ptab_is_valid_id(ptdep->u.element.id)); - ERTS_PTAB_LIST_ASSERT( - erts_ptab_data2ix(ptab, - ERTS_PTAB_ID2DATA(ptdep->u.element.id)) - == ptdep->ix); + ERTS_PTAB_LIST_ASSERT(erts_ptab_id2pix(ptab, + ptdep->u.element.id) + == ptdep->ix); } } -- cgit v1.2.3