X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fgencgc.c;h=18687975ce20bc096c1f60ce14c38d372a3f76ff;hb=beddcfe1ea23d2cfdddde2fa7cde6436799715a2;hp=0e787c30c3ac7d4f36bf2072c294a27e40481819;hpb=87cce4bfe714163f5ab7d211f439db567c7278d1;p=sbcl.git diff --git a/src/runtime/gencgc.c b/src/runtime/gencgc.c index 0e787c3..1868797 100644 --- a/src/runtime/gencgc.c +++ b/src/runtime/gencgc.c @@ -81,7 +81,13 @@ enum { boolean enable_page_protection = 1; /* the minimum size (in bytes) for a large object*/ +#if (GENCGC_ALLOC_GRANULARITY >= PAGE_BYTES) && (GENCGC_ALLOC_GRANULARITY >= GENCGC_CARD_BYTES) long large_object_size = 4 * GENCGC_ALLOC_GRANULARITY; +#elif (GENCGC_CARD_BYTES >= PAGE_BYTES) && (GENCGC_CARD_BYTES >= GENCGC_ALLOC_GRANULARITY) +long large_object_size = 4 * GENCGC_CARD_BYTES; +#else +long large_object_size = 4 * PAGE_BYTES; +#endif /* @@ -358,6 +364,9 @@ static pthread_mutex_t allocation_lock = PTHREAD_MUTEX_INITIALIZER; extern unsigned long gencgc_release_granularity; unsigned long gencgc_release_granularity = GENCGC_RELEASE_GRANULARITY; +extern unsigned long gencgc_alloc_granularity; +unsigned long gencgc_alloc_granularity = GENCGC_ALLOC_GRANULARITY; + /* * miscellaneous heap functions @@ -627,6 +636,15 @@ zero_pages(page_index_t start, page_index_t end) { } +static void +zero_and_mark_pages(page_index_t start, page_index_t end) { + page_index_t i; + + zero_pages(start, end); + for (i = start; i <= end; i++) + page_table[i].need_to_zero = 0; +} + /* Zero the pages from START to END (inclusive), except for those * pages that are known to already zeroed. Mark all pages in the * ranges as non-zeroed. @@ -1263,84 +1281,87 @@ gc_find_freeish_pages(page_index_t *restart_page_ptr, long nbytes, { page_index_t first_page, last_page; page_index_t restart_page = *restart_page_ptr; + long nbytes_goal = nbytes; long bytes_found = 0; long most_bytes_found = 0; + page_index_t most_bytes_found_from, most_bytes_found_to; + int small_object = nbytes < GENCGC_CARD_BYTES; /* FIXME: assert(free_pages_lock is held); */ + if (nbytes_goal < gencgc_alloc_granularity) + nbytes_goal = gencgc_alloc_granularity; + /* Toggled by gc_and_save for heap compaction, normally -1. */ if (gencgc_alloc_start_page != -1) { restart_page = gencgc_alloc_start_page; } gc_assert(nbytes>=0); - if (((unsigned long)nbytes)>=GENCGC_CARD_BYTES) { - /* Search for a contiguous free space of at least nbytes, - * aligned on a page boundary. The page-alignment is strictly - * speaking needed only for objects at least large_object_size - * bytes in size. */ - do { - first_page = restart_page; - while ((first_page < page_table_pages) && - page_allocated_p(first_page)) + /* Search for a page with at least nbytes of space. We prefer + * not to split small objects on multiple pages, to reduce the + * number of contiguous allocation regions spaning multiple + * pages: this helps avoid excessive conservativism. + * + * For other objects, we guarantee that they start on their own + * page boundary. + */ + first_page = restart_page; + while (first_page < page_table_pages) { + bytes_found = 0; + if (page_free_p(first_page)) { + gc_assert(0 == page_table[first_page].bytes_used); + bytes_found = GENCGC_CARD_BYTES; + } else if (small_object && + (page_table[first_page].allocated == page_type_flag) && + (page_table[first_page].large_object == 0) && + (page_table[first_page].gen == gc_alloc_generation) && + (page_table[first_page].write_protected == 0) && + (page_table[first_page].dont_move == 0)) { + bytes_found = GENCGC_CARD_BYTES - page_table[first_page].bytes_used; + if (bytes_found < nbytes) { + if (bytes_found > most_bytes_found) + most_bytes_found = bytes_found; first_page++; - - last_page = first_page; - bytes_found = GENCGC_CARD_BYTES; - while ((bytes_found < nbytes) && - (last_page < (page_table_pages-1)) && - page_free_p(last_page+1)) { - last_page++; - bytes_found += GENCGC_CARD_BYTES; - gc_assert(0 == page_table[last_page].bytes_used); - gc_assert(0 == page_table[last_page].write_protected); + continue; } - if (bytes_found > most_bytes_found) - most_bytes_found = bytes_found; - restart_page = last_page + 1; - } while ((restart_page < page_table_pages) && (bytes_found < nbytes)); - - } else { - /* Search for a page with at least nbytes of space. We prefer - * not to split small objects on multiple pages, to reduce the - * number of contiguous allocation regions spaning multiple - * pages: this helps avoid excessive conservativism. */ - first_page = restart_page; - while (first_page < page_table_pages) { - if (page_free_p(first_page)) - { - gc_assert(0 == page_table[first_page].bytes_used); - bytes_found = GENCGC_CARD_BYTES; - break; - } - else if ((page_table[first_page].allocated == page_type_flag) && - (page_table[first_page].large_object == 0) && - (page_table[first_page].gen == gc_alloc_generation) && - (page_table[first_page].write_protected == 0) && - (page_table[first_page].dont_move == 0)) - { - bytes_found = GENCGC_CARD_BYTES - - page_table[first_page].bytes_used; - if (bytes_found > most_bytes_found) - most_bytes_found = bytes_found; - if (bytes_found >= nbytes) - break; - } + } else { first_page++; + continue; } - last_page = first_page; - restart_page = first_page + 1; + + gc_assert(page_table[first_page].write_protected == 0); + for (last_page = first_page+1; + ((last_page < page_table_pages) && + page_free_p(last_page) && + (bytes_found < nbytes_goal)); + last_page++) { + bytes_found += GENCGC_CARD_BYTES; + gc_assert(0 == page_table[last_page].bytes_used); + gc_assert(0 == page_table[last_page].write_protected); + } + + if (bytes_found > most_bytes_found) { + most_bytes_found = bytes_found; + most_bytes_found_from = first_page; + most_bytes_found_to = last_page; + } + if (bytes_found >= nbytes_goal) + break; + + first_page = last_page; } + bytes_found = most_bytes_found; + restart_page = first_page + 1; + /* Check for a failure */ if (bytes_found < nbytes) { gc_assert(restart_page >= page_table_pages); gc_heap_exhausted_error_or_lose(most_bytes_found, nbytes); } - gc_assert(page_table[first_page].write_protected == 0); - - *restart_page_ptr = first_page; - return last_page; + *restart_page_ptr = most_bytes_found_from; + return most_bytes_found_to-1; } /* Allocate bytes. All the rest of the special-purpose allocation @@ -4262,22 +4283,16 @@ update_dynamic_space_free_pointer(void) } static void -remap_page_range (page_index_t from, page_index_t to, int forcibly) +remap_page_range (page_index_t from, page_index_t to) { /* There's a mysterious Solaris/x86 problem with using mmap * tricks for memory zeroing. See sbcl-devel thread * "Re: patch: standalone executable redux". - * - * Since pages don't have to be zeroed ahead of time, only do - * so when called from purify. */ #if defined(LISP_FEATURE_SUNOS) - if (forcibly) - zero_pages(from, to); + zero_and_mark_pages(from, to); #else - page_index_t aligned_from, aligned_end, end = to+1; - - const page_index_t + const page_index_t release_granularity = gencgc_release_granularity/GENCGC_CARD_BYTES, release_mask = release_granularity-1, end = to+1, @@ -4286,29 +4301,24 @@ remap_page_range (page_index_t from, page_index_t to, int forcibly) if (aligned_from < aligned_end) { zero_pages_with_mmap(aligned_from, aligned_end-1); - if (forcibly) { - if (aligned_from != from) - zero_pages(from, aligned_from-1); - if (aligned_end != end) - zero_pages(aligned_end, end-1); - } - } else if (forcibly) - zero_pages(from, to); + if (aligned_from != from) + zero_and_mark_pages(from, aligned_from-1); + if (aligned_end != end) + zero_and_mark_pages(aligned_end, end-1); + } else { + zero_and_mark_pages(from, to); + } #endif } static void remap_free_pages (page_index_t from, page_index_t to, int forcibly) { - page_index_t first_page, last_page, - first_aligned_page, last_aligned_page; + page_index_t first_page, last_page; if (forcibly) - return remap_page_range(from, to, 1); + return remap_page_range(from, to); - /* See comment above about mysterious failures on Solaris/x86. - */ -#if !defined(LISP_FEATURE_SUNOS) for (first_page = from; first_page <= to; first_page++) { if (page_allocated_p(first_page) || (page_table[first_page].need_to_zero == 0)) @@ -4320,11 +4330,10 @@ remap_free_pages (page_index_t from, page_index_t to, int forcibly) (page_table[last_page].need_to_zero == 1)) last_page++; - remap_page_range(first_page, last_page-1, 0); + remap_page_range(first_page, last_page-1); first_page = last_page; } -#endif } generation_index_t small_generation_limit = 1;