diff options
Diffstat (limited to 'libnetdata/arrayalloc/arrayalloc.c')
| -rw-r--r-- | libnetdata/arrayalloc/arrayalloc.c | 340 |
1 files changed, 247 insertions, 93 deletions
diff --git a/libnetdata/arrayalloc/arrayalloc.c b/libnetdata/arrayalloc/arrayalloc.c index bdf1384d4..f337279ae 100644 --- a/libnetdata/arrayalloc/arrayalloc.c +++ b/libnetdata/arrayalloc/arrayalloc.c @@ -6,7 +6,9 @@ #define ARAL_MAX_PAGE_SIZE_MMAP (1*1024*1024*1024) // max malloc size -#define ARAL_MAX_PAGE_SIZE_MALLOC (10*1024*1024) +// optimal at current versions of libc is up to 256k +// ideal to have the same overhead as libc is 4k +#define ARAL_MAX_PAGE_SIZE_MALLOC (64*1024) typedef struct arrayalloc_free { size_t size; @@ -32,6 +34,33 @@ static inline size_t natural_alignment(size_t size, size_t alignment) { return size; } +static void arrayalloc_delete_leftover_files(const char *path, const char *required_prefix) { + DIR *dir = opendir(path); + if(!dir) return; + + char fullpath[FILENAME_MAX + 1]; + size_t len = strlen(required_prefix); + + struct dirent *de = NULL; + while((de = readdir(dir))) { + if(de->d_type == DT_DIR) + continue; + + if(strncmp(de->d_name, required_prefix, len) != 0) + continue; + + snprintfz(fullpath, FILENAME_MAX, "%s/%s", path, de->d_name); + info("ARRAYALLOC: removing left-over file '%s'", fullpath); + if(unlikely(unlink(fullpath) == -1)) + error("Cannot delete file '%s'", fullpath); + } + + closedir(dir); +} + +// ---------------------------------------------------------------------------- +// arrayalloc_init() + static void arrayalloc_init(ARAL *ar) { static netdata_mutex_t mutex = NETDATA_MUTEX_INITIALIZER; netdata_mutex_lock(&mutex); @@ -47,7 +76,7 @@ static void arrayalloc_init(ARAL *ar) { // we need to add a page pointer after the element // so, first align the element size to the pointer size - ar->internal.element_size = natural_alignment(ar->element_size, sizeof(uintptr_t)); + ar->internal.element_size = natural_alignment(ar->requested_element_size, sizeof(uintptr_t)); // then add the size of a pointer to it ar->internal.element_size += sizeof(uintptr_t); @@ -59,18 +88,18 @@ static void arrayalloc_init(ARAL *ar) { // and finally align it to the natural alignment ar->internal.element_size = natural_alignment(ar->internal.element_size, ARAL_NATURAL_ALIGNMENT); - // this is where we should write the pointer + // we write the page pointer just after each element ar->internal.page_ptr_offset = ar->internal.element_size - sizeof(uintptr_t); - if(ar->element_size + sizeof(uintptr_t) > ar->internal.element_size) + if(ar->requested_element_size + sizeof(uintptr_t) > ar->internal.element_size) fatal("ARRAYALLOC: failed to calculate properly page_ptr_offset: element size %zu, sizeof(uintptr_t) %zu, natural alignment %zu, final element size %zu, page_ptr_offset %zu", - ar->element_size, sizeof(uintptr_t), ARAL_NATURAL_ALIGNMENT, ar->internal.element_size, ar->internal.page_ptr_offset); + ar->requested_element_size, sizeof(uintptr_t), ARAL_NATURAL_ALIGNMENT, ar->internal.element_size, ar->internal.page_ptr_offset); //info("ARRAYALLOC: element size %zu, sizeof(uintptr_t) %zu, natural alignment %zu, final element size %zu, page_ptr_offset %zu", // ar->element_size, sizeof(uintptr_t), ARAL_NATURAL_ALIGNMENT, ar->internal.element_size, ar->internal.page_ptr_offset); - if (ar->elements < 10) - ar->elements = 10; + if (ar->initial_elements < 10) + ar->initial_elements = 10; ar->internal.mmap = (ar->use_mmap && ar->cache_dir && *ar->cache_dir) ? true : false; ar->internal.max_alloc_size = ar->internal.mmap ? ARAL_MAX_PAGE_SIZE_MMAP : ARAL_MAX_PAGE_SIZE_MALLOC; @@ -81,17 +110,20 @@ static void arrayalloc_init(ARAL *ar) { if(ar->internal.max_alloc_size % ar->internal.element_size) ar->internal.max_alloc_size -= ar->internal.max_alloc_size % ar->internal.element_size; - ar->internal.first_page = NULL; - ar->internal.last_page = NULL; + ar->internal.pages = NULL; ar->internal.allocation_multiplier = 1; ar->internal.file_number = 0; if(ar->internal.mmap) { - char filename[FILENAME_MAX + 1]; - snprintfz(filename, FILENAME_MAX, "%s/array_alloc.mmap", *ar->cache_dir); - int r = mkdir(filename, 0775); + char directory_name[FILENAME_MAX + 1]; + snprintfz(directory_name, FILENAME_MAX, "%s/array_alloc.mmap", *ar->cache_dir); + int r = mkdir(directory_name, 0775); if (r != 0 && errno != EEXIST) - fatal("Cannot create directory '%s'", filename); + fatal("Cannot create directory '%s'", directory_name); + + char filename[FILENAME_MAX + 1]; + snprintfz(filename, FILENAME_MAX, "%s.", ar->filename); + arrayalloc_delete_leftover_files(directory_name, filename); } ar->internal.initialized = true; @@ -100,8 +132,11 @@ static void arrayalloc_init(ARAL *ar) { netdata_mutex_unlock(&mutex); } +// ---------------------------------------------------------------------------- +// check a free slot + #ifdef NETDATA_INTERNAL_CHECKS -static inline void arrayalloc_free_checks(ARAL *ar, ARAL_FREE *fr) { +static inline void arrayalloc_free_validate_internal_check(ARAL *ar, ARAL_FREE *fr) { if(fr->size < ar->internal.element_size) fatal("ARRAYALLOC: free item of size %zu, less than the expected element size %zu", fr->size, ar->internal.element_size); @@ -109,65 +144,58 @@ static inline void arrayalloc_free_checks(ARAL *ar, ARAL_FREE *fr) { fatal("ARRAYALLOC: free item of size %zu is not multiple to element size %zu", fr->size, ar->internal.element_size); } #else -#define arrayalloc_free_checks(ar, fr) debug_dummy() +#define arrayalloc_free_validate_internal_check(ar, fr) debug_dummy() #endif -static inline void unlink_page(ARAL *ar, ARAL_PAGE *page) { - if(unlikely(!page)) return; - - if(page->next) - page->next->prev = page->prev; - - if(page->prev) - page->prev->next = page->next; - - if(page == ar->internal.first_page) - ar->internal.first_page = page->next; - - if(page == ar->internal.last_page) - ar->internal.last_page = page->prev; -} +// ---------------------------------------------------------------------------- +// find the page a pointer belongs to -static inline void link_page_first(ARAL *ar, ARAL_PAGE *page) { - page->prev = NULL; - page->next = ar->internal.first_page; - if(page->next) page->next->prev = page; +#ifdef NETDATA_INTERNAL_CHECKS +static inline ARAL_PAGE *find_page_with_allocation_internal_check(ARAL *ar, void *ptr) { + uintptr_t seeking = (uintptr_t)ptr; + ARAL_PAGE *page; - ar->internal.first_page = page; + for(page = ar->internal.pages; page ; page = page->next) { + if(unlikely(seeking >= (uintptr_t)page->data && seeking < (uintptr_t)page->data + page->size)) + break; + } - if(!ar->internal.last_page) - ar->internal.last_page = page; + return page; } +#endif -static inline void link_page_last(ARAL *ar, ARAL_PAGE *page) { - page->next = NULL; - page->prev = ar->internal.last_page; - if(page->prev) page->prev->next = page; - - ar->internal.last_page = page; - - if(!ar->internal.first_page) - ar->internal.first_page = page; -} +// ---------------------------------------------------------------------------- +// find a page with a free slot (there shouldn't be any) -static inline ARAL_PAGE *find_page_with_allocation(ARAL *ar, void *ptr) { - uintptr_t seeking = (uintptr_t)ptr; +#ifdef NETDATA_INTERNAL_CHECKS +static inline ARAL_PAGE *find_page_with_free_slots_internal_check(ARAL *ar) { ARAL_PAGE *page; - for(page = ar->internal.first_page; page ; page = page->next) { - if(unlikely(seeking >= (uintptr_t)page->data && seeking < (uintptr_t)page->data + page->size)) + for(page = ar->internal.pages; page ; page = page->next) { + if(page->free_list) break; + + internal_fatal(page->size - page->used_elements * ar->internal.element_size >= ar->internal.element_size, + "ARRAYALLOC: a page is marked full, but it is not!"); + + internal_fatal(page->size < page->used_elements * ar->internal.element_size, + "ARRAYALLOC: a page has been overflown!"); } return page; } +#endif -static void arrayalloc_increase(ARAL *ar) { +#ifdef NETDATA_TRACE_ALLOCATIONS +static void arrayalloc_add_page(ARAL *ar, const char *file, const char *function, size_t line) { +#else +static void arrayalloc_add_page(ARAL *ar) { +#endif if(unlikely(!ar->internal.initialized)) arrayalloc_init(ar); ARAL_PAGE *page = callocz(1, sizeof(ARAL_PAGE)); - page->size = ar->elements * ar->internal.element_size * ar->internal.allocation_multiplier; + page->size = ar->initial_elements * ar->internal.element_size * ar->internal.allocation_multiplier; if(page->size > ar->internal.max_alloc_size) page->size = ar->internal.max_alloc_size; else @@ -182,8 +210,13 @@ static void arrayalloc_increase(ARAL *ar) { if (unlikely(!page->data)) fatal("Cannot allocate arrayalloc buffer of size %zu on filename '%s'", page->size, page->filename); } - else + else { +#ifdef NETDATA_TRACE_ALLOCATIONS + page->data = mallocz_int(page->size, file, function, line); +#else page->data = mallocz(page->size); +#endif + } // link the free space to its page ARAL_FREE *fr = (ARAL_FREE *)page->data; @@ -193,9 +226,9 @@ static void arrayalloc_increase(ARAL *ar) { page->free_list = fr; // link the new page at the front of the list of pages - link_page_first(ar, page); + DOUBLE_LINKED_LIST_PREPEND_UNSAFE(ar->internal.pages, page, prev, next); - arrayalloc_free_checks(ar, fr); + arrayalloc_free_validate_internal_check(ar, fr); } static void arrayalloc_lock(ARAL *ar) { @@ -208,63 +241,92 @@ static void arrayalloc_unlock(ARAL *ar) { netdata_mutex_unlock(&ar->internal.mutex); } -ARAL *arrayalloc_create(size_t element_size, size_t elements, const char *filename, char **cache_dir) { +ARAL *arrayalloc_create(size_t element_size, size_t elements, const char *filename, char **cache_dir, bool mmap) { ARAL *ar = callocz(1, sizeof(ARAL)); - ar->element_size = element_size; - ar->elements = elements; + ar->requested_element_size = element_size; + ar->initial_elements = elements; ar->filename = filename; ar->cache_dir = cache_dir; + ar->use_mmap = mmap; return ar; } +#ifdef NETDATA_TRACE_ALLOCATIONS +void *arrayalloc_mallocz_int(ARAL *ar, const char *file, const char *function, size_t line) { +#else void *arrayalloc_mallocz(ARAL *ar) { +#endif + if(unlikely(!ar->internal.initialized)) + arrayalloc_init(ar); + arrayalloc_lock(ar); - if(unlikely(!ar->internal.first_page || !ar->internal.first_page->free_list)) - arrayalloc_increase(ar); + if(unlikely(!ar->internal.pages || !ar->internal.pages->free_list)) { + internal_fatal(find_page_with_free_slots_internal_check(ar) != NULL, + "ARRAYALLOC: first page does not have any free slots, but there is another that has!"); - ARAL_PAGE *page = ar->internal.first_page; - ARAL_FREE *fr = page->free_list; +#ifdef NETDATA_TRACE_ALLOCATIONS + arrayalloc_add_page(ar, file, function, line); +#else + arrayalloc_add_page(ar); +#endif + } + + ARAL_PAGE *page = ar->internal.pages; + ARAL_FREE *found_fr = page->free_list; - if(unlikely(!fr)) - fatal("ARRAYALLOC: free item cannot be NULL."); + internal_fatal(!found_fr, + "ARRAYALLOC: free item to use, cannot be NULL."); - if(unlikely(fr->size < ar->internal.element_size)) - fatal("ARRAYALLOC: free item size %zu is smaller than %zu", fr->size, ar->internal.element_size); + internal_fatal(found_fr->size < ar->internal.element_size, + "ARRAYALLOC: free item size %zu, cannot be smaller than %zu", + found_fr->size, ar->internal.element_size); - if(fr->size - ar->internal.element_size <= ar->internal.element_size) { - // we are done with this page - page->free_list = NULL; + if(unlikely(found_fr->size - ar->internal.element_size < ar->internal.element_size)) { + // we can use the entire free space entry - if(page != ar->internal.last_page) { - unlink_page(ar, page); - link_page_last(ar, page); + page->free_list = found_fr->next; + + if(unlikely(!page->free_list)) { + // we are done with this page + // move the full page last + // so that pages with free items remain first in the list + DOUBLE_LINKED_LIST_REMOVE_UNSAFE(ar->internal.pages, page, prev, next); + DOUBLE_LINKED_LIST_APPEND_UNSAFE(ar->internal.pages, page, prev, next); } } else { - uint8_t *data = (uint8_t *)fr; - ARAL_FREE *fr2 = (ARAL_FREE *)&data[ar->internal.element_size]; - fr2->page = fr->page; - fr2->size = fr->size - ar->internal.element_size; - fr2->next = fr->next; - page->free_list = fr2; - - arrayalloc_free_checks(ar, fr2); + // we can split the free space entry + + uint8_t *data = (uint8_t *)found_fr; + ARAL_FREE *fr = (ARAL_FREE *)&data[ar->internal.element_size]; + fr->page = page; + fr->size = found_fr->size - ar->internal.element_size; + + // link the free slot first in the page + fr->next = found_fr->next; + page->free_list = fr; + + arrayalloc_free_validate_internal_check(ar, fr); } - fr->page->used_elements++; + page->used_elements++; // put the page pointer after the element - uint8_t *data = (uint8_t *)fr; + uint8_t *data = (uint8_t *)found_fr; ARAL_PAGE **page_ptr = (ARAL_PAGE **)&data[ar->internal.page_ptr_offset]; *page_ptr = page; arrayalloc_unlock(ar); - return (void *)fr; + return (void *)found_fr; } +#ifdef NETDATA_TRACE_ALLOCATIONS +void arrayalloc_freez_int(ARAL *ar, void *ptr, const char *file, const char *function, size_t line) { +#else void arrayalloc_freez(ARAL *ar, void *ptr) { - if(!ptr) return; +#endif + if(unlikely(!ptr)) return; arrayalloc_lock(ar); // get the page pointer @@ -282,10 +344,10 @@ void arrayalloc_freez(ARAL *ar, void *ptr) { #endif } -#ifdef NETDATA_INTERNAL_CHECKS +#ifdef NETDATA_ARRAYALLOC_INTERNAL_CHECKS { // find the page ptr belongs - ARAL_PAGE *page2 = find_page_with_allocation(ar, ptr); + ARAL_PAGE *page2 = find_page_with_allocation_internal_check(ar, ptr); if(unlikely(page != page2)) fatal("ARRAYALLOC: page pointers do not match!"); @@ -312,24 +374,116 @@ void arrayalloc_freez(ARAL *ar, void *ptr) { // if the page is empty, release it if(!page->used_elements) { - unlink_page(ar, page); + DOUBLE_LINKED_LIST_REMOVE_UNSAFE(ar->internal.pages, page, prev, next); // free it if(ar->internal.mmap) { - munmap(page->data, page->size); + netdata_munmap(page->data, page->size); if (unlikely(unlink(page->filename) == 1)) error("Cannot delete file '%s'", page->filename); freez((void *)page->filename); } - else + else { +#ifdef NETDATA_TRACE_ALLOCATIONS + freez_int(page->data, file, function, line); +#else freez(page->data); +#endif + } freez(page); } - else if(page != ar->internal.first_page) { - unlink_page(ar, page); - link_page_first(ar, page); + else if(page != ar->internal.pages) { + // move the page with free item first + // so that the next allocation will use this page + DOUBLE_LINKED_LIST_REMOVE_UNSAFE(ar->internal.pages, page, prev, next); + DOUBLE_LINKED_LIST_PREPEND_UNSAFE(ar->internal.pages, page, prev, next); } arrayalloc_unlock(ar); } + +int aral_unittest(size_t elements) { + char *cache_dir = "/tmp/"; + ARAL *ar = arrayalloc_create(20, 10, "test-aral", &cache_dir, false); + + void *pointers[elements]; + + for(size_t i = 0; i < elements ;i++) { + pointers[i] = arrayalloc_mallocz(ar); + } + + for(size_t div = 5; div >= 2 ;div--) { + for (size_t i = 0; i < elements / div; i++) { + arrayalloc_freez(ar, pointers[i]); + } + + for (size_t i = 0; i < elements / div; i++) { + pointers[i] = arrayalloc_mallocz(ar); + } + } + + for(size_t step = 50; step >= 10 ;step -= 10) { + for (size_t i = 0; i < elements; i += step) { + arrayalloc_freez(ar, pointers[i]); + } + + for (size_t i = 0; i < elements; i += step) { + pointers[i] = arrayalloc_mallocz(ar); + } + } + + for(size_t i = 0; i < elements ;i++) { + arrayalloc_freez(ar, pointers[i]); + } + + if(ar->internal.pages) { + fprintf(stderr, "ARAL leftovers detected (1)"); + return 1; + } + + size_t ops = 0; + size_t increment = elements / 10; + size_t allocated = 0; + for(size_t all = increment; all <= elements ; all += increment) { + + for(; allocated < all ; allocated++) { + pointers[allocated] = arrayalloc_mallocz(ar); + ops++; + } + + size_t to_free = now_realtime_usec() % all; + size_t free_list[to_free]; + for(size_t i = 0; i < to_free ;i++) { + size_t pos; + do { + pos = now_realtime_usec() % all; + } while(!pointers[pos]); + + arrayalloc_freez(ar, pointers[pos]); + pointers[pos] = NULL; + free_list[i] = pos; + ops++; + } + + for(size_t i = 0; i < to_free ;i++) { + size_t pos = free_list[i]; + pointers[pos] = arrayalloc_mallocz(ar); + ops++; + } + } + + for(size_t i = 0; i < allocated - 1 ;i++) { + arrayalloc_freez(ar, pointers[i]); + ops++; + } + + arrayalloc_freez(ar, pointers[allocated - 1]); + + if(ar->internal.pages) { + fprintf(stderr, "ARAL leftovers detected (2)"); + return 1; + } + + return 0; +} |