This moves the reusable parts of the memory pool logic used by fast-import.c into its own file for use by other components. Signed-off-by: Jameson Miller <jamill@xxxxxxxxxxxxx> --- Makefile | 1 + fast-import.c | 118 +--------------------------------------------------------- mem-pool.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++ mem-pool.h | 34 +++++++++++++++++ 4 files changed, 139 insertions(+), 117 deletions(-) create mode 100644 mem-pool.c create mode 100644 mem-pool.h diff --git a/Makefile b/Makefile index a1d8775adb..1e142b1dd9 100644 --- a/Makefile +++ b/Makefile @@ -832,6 +832,7 @@ LIB_OBJS += lockfile.o LIB_OBJS += log-tree.o LIB_OBJS += mailinfo.o LIB_OBJS += mailmap.o +LIB_OBJS += mem-pool.o LIB_OBJS += match-trees.o LIB_OBJS += merge.o LIB_OBJS += merge-blobs.o diff --git a/fast-import.c b/fast-import.c index 519e1cbd7f..36ac5760d6 100644 --- a/fast-import.c +++ b/fast-import.c @@ -168,6 +168,7 @@ Format of STDIN stream: #include "dir.h" #include "run-command.h" #include "packfile.h" +#include "mem-pool.h" #define PACK_ID_BITS 16 #define MAX_PACK_ID ((1<<PACK_ID_BITS)-1) @@ -209,26 +210,6 @@ struct last_object { unsigned no_swap : 1; }; -struct mp_block { - struct mp_block *next_block; - char *next_free; - char *end; - uintmax_t space[FLEX_ARRAY]; /* more */ -}; - -struct mem_pool { - struct mp_block *mp_block; - - /* - * The amount of available memory to grow the pool by. - * This size does not include the overhead for the mp_block. - */ - size_t block_alloc; - - /* The total amount of memory allocated by the pool. */ - size_t pool_alloc; -}; - struct atom_str { struct atom_str *next_atom; unsigned short str_len; @@ -646,103 +627,6 @@ static unsigned int hc_str(const char *s, size_t len) return r; } -static struct mp_block *mem_pool_alloc_block(struct mem_pool *mem_pool) -{ - struct mp_block *p; - - mem_pool->pool_alloc += sizeof(struct mp_block) + mem_pool->block_alloc; - p = xmalloc(st_add(sizeof(struct mp_block), mem_pool->block_alloc)); - p->next_block = mem_pool->mp_block; - p->next_free = (char *)p->space; - p->end = p->next_free + mem_pool->block_alloc; - mem_pool->mp_block = p; - - return p; -} - -/* - * Allocates a block of memory with a specific size and - * appends it to the memory pool's list of blocks. - * - * This function is used to allocate blocks with sizes - * different than the default "block_alloc" size for the mem_pool. - * - * There are two use cases: - * 1) The initial block allocation for a memory pool. - * - * 2) large" blocks of a specific size, where the entire memory block - * is going to be used. This means the block will not have any - * available memory for future allocations. The block is placed at - * the end of the list so that it will be the last block searched - * for available space. - */ -static struct mp_block *mem_pool_alloc_block_with_size(struct mem_pool *mem_pool, size_t block_alloc) -{ - struct mp_block *p, *block; - - mem_pool->pool_alloc += sizeof(struct mp_block) + block_alloc; - p = xmalloc(st_add(sizeof(struct mp_block), block_alloc)); - - block = mem_pool->mp_block; - if (block) { - while (block->next_block) - block = block->next_block; - - block->next_block = p; - } else { - mem_pool->mp_block = p; - } - - p->next_block = NULL; - p->next_free = (char *)p->space; - p->end = p->next_free + block_alloc; - - return p; -} - -static void *mem_pool_alloc(struct mem_pool *mem_pool, size_t len) -{ - struct mp_block *p; - void *r; - - /* round up to a 'uintmax_t' alignment */ - if (len & (sizeof(uintmax_t) - 1)) - len += sizeof(uintmax_t) - (len & (sizeof(uintmax_t) - 1)); - - p = mem_pool->mp_block; - - /* - * In performance profiling, there was a minor perf benefit to - * check for available memory in the head block via the if - * statement, and only going through the loop when needed. - */ - if (p && - (p->end - p->next_free < len)) { - for (p = p->next_block; p; p = p->next_block) - if (p->end - p->next_free >= len) - break; - } - - if (!p) { - if (len >= (mem_pool->block_alloc / 2)) - p = mem_pool_alloc_block_with_size(mem_pool, len); - else - p = mem_pool_alloc_block(mem_pool); - } - - r = p->next_free; - p->next_free += len; - return r; -} - -static void *mem_pool_calloc(struct mem_pool *mem_pool, size_t count, size_t size) -{ - size_t len = st_mult(count, size); - void *r = mem_pool_alloc(mem_pool, len); - memset(r, 0, len); - return r; -} - static char *pool_strdup(const char *s) { size_t len = strlen(s) + 1; diff --git a/mem-pool.c b/mem-pool.c new file mode 100644 index 0000000000..992e354e12 --- /dev/null +++ b/mem-pool.c @@ -0,0 +1,103 @@ +/* + * Memory Pool implementation logic. + */ + +#include "cache.h" +#include "mem-pool.h" + +static struct mp_block *mem_pool_alloc_block(struct mem_pool *mem_pool) +{ + struct mp_block *p; + + mem_pool->pool_alloc += sizeof(struct mp_block) + mem_pool->block_alloc; + p = xmalloc(st_add(sizeof(struct mp_block), mem_pool->block_alloc)); + p->next_block = mem_pool->mp_block; + p->next_free = (char *)p->space; + p->end = p->next_free + mem_pool->block_alloc; + mem_pool->mp_block = p; + + return p; +} + +/* + * Allocates a block of memory with a specific size and + * appends it to the memory pool's list of blocks. + * + * This function is used to allocate blocks with sizes + * different than the default "block_alloc" size for the mem_pool. + * + * There are two use cases: + * 1) The initial block allocation for a memory pool. + * + * 2) large" blocks of a specific size, where the entire memory block + * is going to be used. This means the block will not have any + * available memory for future allocations. The block is placed at + * the end of the list so that it will be the last block searched + * for available space. + */ +static struct mp_block *mem_pool_alloc_block_with_size(struct mem_pool *mem_pool, size_t block_alloc) +{ + struct mp_block *p, *block; + + mem_pool->pool_alloc += sizeof(struct mp_block) + block_alloc; + p = xmalloc(st_add(sizeof(struct mp_block), block_alloc)); + + block = mem_pool->mp_block; + if (block) { + while (block->next_block) + block = block->next_block; + + block->next_block = p; + } else { + mem_pool->mp_block = p; + } + + p->next_block = NULL; + p->next_free = (char *)p->space; + p->end = p->next_free + block_alloc; + + return p; +} + +void *mem_pool_alloc(struct mem_pool *mem_pool, size_t len) +{ + struct mp_block *p; + void *r; + + /* round up to a 'uintmax_t' alignment */ + if (len & (sizeof(uintmax_t) - 1)) + len += sizeof(uintmax_t) - (len & (sizeof(uintmax_t) - 1)); + + p = mem_pool->mp_block; + + /* + * In performance profiling, there was a minor perf benefit to + * check for available memory in the head block via the if + * statement, and only going through the loop when needed. + */ + if (p && + (p->end - p->next_free < len)) { + for (p = p->next_block; p; p = p->next_block) + if (p->end - p->next_free >= len) + break; + } + + if (!p) { + if (len >= (mem_pool->block_alloc / 2)) + p = mem_pool_alloc_block_with_size(mem_pool, len); + else + p = mem_pool_alloc_block(mem_pool); + } + + r = p->next_free; + p->next_free += len; + return r; +} + +void *mem_pool_calloc(struct mem_pool *mem_pool, size_t count, size_t size) +{ + size_t len = st_mult(count, size); + void *r = mem_pool_alloc(mem_pool, len); + memset(r, 0, len); + return r; +} diff --git a/mem-pool.h b/mem-pool.h new file mode 100644 index 0000000000..829ad58ecf --- /dev/null +++ b/mem-pool.h @@ -0,0 +1,34 @@ +#ifndef MEM_POOL_H +#define MEM_POOL_H + +struct mp_block { + struct mp_block *next_block; + char *next_free; + char *end; + uintmax_t space[FLEX_ARRAY]; /* more */ +}; + +struct mem_pool { + struct mp_block *mp_block; + + /* + * The amount of available memory to grow the pool by. + * This size does not include the overhead for the mp_block. + */ + size_t block_alloc; + + /* The total amount of memory allocated by the pool. */ + size_t pool_alloc; +}; + +/* + * Alloc memory from the mem_pool. + */ +void *mem_pool_alloc(struct mem_pool *pool, size_t len); + +/* + * Allocate and zero memory from the memory pool. + */ +void *mem_pool_calloc(struct mem_pool *pool, size_t count, size_t size); + +#endif -- 2.14.3