?zmalloc.c? 文件源代碼：

#include <stdio.h> #include <stdlib.h>/* This function provide us access to the original libc free(). This is useful* for instance to free results obtained by backtrace_symbols(). We need* to define this function before including zmalloc.h that may shadow the* free implementation if we use jemalloc or another non standard allocator. */ void zlibc_free(void *ptr) {free(ptr); }#include <string.h> #include <pthread.h> #include "config.h" #include "zmalloc.h"#ifdef HAVE_MALLOC_SIZE #define PREFIX_SIZE (0) #else #if defined(__sun) || defined(__sparc) || defined(__sparc__) #define PREFIX_SIZE (sizeof(long long)) #else #define PREFIX_SIZE (sizeof(size_t)) #endif #endif/* Explicitly override malloc/free etc when using tcmalloc. */ #if defined(USE_TCMALLOC) #define malloc(size) tc_malloc(size) #define calloc(count,size) tc_calloc(count,size) #define realloc(ptr,size) tc_realloc(ptr,size) #define free(ptr) tc_free(ptr) #elif defined(USE_JEMALLOC) #define malloc(size) je_malloc(size) #define calloc(count,size) je_calloc(count,size) #define realloc(ptr,size) je_realloc(ptr,size) #define free(ptr) je_free(ptr) #endif#if defined(__ATOMIC_RELAXED) #define update_zmalloc_stat_add(__n) __atomic_add_fetch(&used_memory, (__n), __ATOMIC_RELAXED) #define update_zmalloc_stat_sub(__n) __atomic_sub_fetch(&used_memory, (__n), __ATOMIC_RELAXED) #elif defined(HAVE_ATOMIC) #define update_zmalloc_stat_add(__n) __sync_add_and_fetch(&used_memory, (__n)) #define update_zmalloc_stat_sub(__n) __sync_sub_and_fetch(&used_memory, (__n)) #else #define update_zmalloc_stat_add(__n) do { \pthread_mutex_lock(&used_memory_mutex); \used_memory += (__n); \pthread_mutex_unlock(&used_memory_mutex); \ } while(0)#define update_zmalloc_stat_sub(__n) do { \pthread_mutex_lock(&used_memory_mutex); \used_memory -= (__n); \pthread_mutex_unlock(&used_memory_mutex); \ } while(0)#endif#define update_zmalloc_stat_alloc(__n) do { \size_t _n = (__n); \if (_n&(sizeof(long)-1)) _n += sizeof(long)-(_n&(sizeof(long)-1)); \if (zmalloc_thread_safe) { \update_zmalloc_stat_add(_n); \} else { \used_memory += _n; \} \ } while(0)#define update_zmalloc_stat_free(__n) do { \size_t _n = (__n); \if (_n&(sizeof(long)-1)) _n += sizeof(long)-(_n&(sizeof(long)-1)); \if (zmalloc_thread_safe) { \update_zmalloc_stat_sub(_n); \} else { \used_memory -= _n; \} \ } while(0)static size_t used_memory = 0; static int zmalloc_thread_safe = 0; pthread_mutex_t used_memory_mutex = PTHREAD_MUTEX_INITIALIZER;static void zmalloc_default_oom(size_t size) {fprintf(stderr, "zmalloc: Out of memory trying to allocate %zu bytes\n",size);fflush(stderr);abort(); }static void (*zmalloc_oom_handler)(size_t) = zmalloc_default_oom;void *zmalloc(size_t size) {void *ptr = malloc(size+PREFIX_SIZE);if (!ptr) zmalloc_oom_handler(size); #ifdef HAVE_MALLOC_SIZEupdate_zmalloc_stat_alloc(zmalloc_size(ptr));return ptr; #else*((size_t*)ptr) = size;update_zmalloc_stat_alloc(size+PREFIX_SIZE);return (char*)ptr+PREFIX_SIZE; #endif }void *zcalloc(size_t size) {void *ptr = calloc(1, size+PREFIX_SIZE);if (!ptr) zmalloc_oom_handler(size); #ifdef HAVE_MALLOC_SIZEupdate_zmalloc_stat_alloc(zmalloc_size(ptr));return ptr; #else*((size_t*)ptr) = size;update_zmalloc_stat_alloc(size+PREFIX_SIZE);return (char*)ptr+PREFIX_SIZE; #endif }void *zrealloc(void *ptr, size_t size) { #ifndef HAVE_MALLOC_SIZEvoid *realptr; #endifsize_t oldsize;void *newptr;if (ptr == NULL) return zmalloc(size); #ifdef HAVE_MALLOC_SIZEoldsize = zmalloc_size(ptr);newptr = realloc(ptr,size);if (!newptr) zmalloc_oom_handler(size);update_zmalloc_stat_free(oldsize);update_zmalloc_stat_alloc(zmalloc_size(newptr));return newptr; #elserealptr = (char*)ptr-PREFIX_SIZE;oldsize = *((size_t*)realptr);newptr = realloc(realptr,size+PREFIX_SIZE);if (!newptr) zmalloc_oom_handler(size);*((size_t*)newptr) = size;update_zmalloc_stat_free(oldsize);update_zmalloc_stat_alloc(size);return (char*)newptr+PREFIX_SIZE; #endif }/* Provide zmalloc_size() for systems where this function is not provided by* malloc itself, given that in that case we store a header with this* information as the first bytes of every allocation. */ #ifndef HAVE_MALLOC_SIZE size_t zmalloc_size(void *ptr) {void *realptr = (char*)ptr-PREFIX_SIZE;size_t size = *((size_t*)realptr);/* Assume at least that all the allocations are padded at sizeof(long) by* the underlying allocator. */if (size&(sizeof(long)-1)) size += sizeof(long)-(size&(sizeof(long)-1));return size+PREFIX_SIZE; } #endifvoid zfree(void *ptr) { #ifndef HAVE_MALLOC_SIZEvoid *realptr;size_t oldsize; #endifif (ptr == NULL) return; #ifdef HAVE_MALLOC_SIZEupdate_zmalloc_stat_free(zmalloc_size(ptr));free(ptr); #elserealptr = (char*)ptr-PREFIX_SIZE;oldsize = *((size_t*)realptr);update_zmalloc_stat_free(oldsize+PREFIX_SIZE);free(realptr); #endif }char *zstrdup(const char *s) {size_t l = strlen(s)+1;char *p = zmalloc(l);memcpy(p,s,l);return p; }size_t zmalloc_used_memory(void) {size_t um;if (zmalloc_thread_safe) { #if defined(__ATOMIC_RELAXED) || defined(HAVE_ATOMIC)um = update_zmalloc_stat_add(0); #elsepthread_mutex_lock(&used_memory_mutex);um = used_memory;pthread_mutex_unlock(&used_memory_mutex); #endif}else {um = used_memory;}return um; }void zmalloc_enable_thread_safeness(void) {zmalloc_thread_safe = 1; }void zmalloc_set_oom_handler(void (*oom_handler)(size_t)) {zmalloc_oom_handler = oom_handler; }/* Get the RSS information in an OS-specific way.** WARNING: the function zmalloc_get_rss() is not designed to be fast* and may not be called in the busy loops where Redis tries to release* memory expiring or swapping out objects.** For this kind of "fast RSS reporting" usages use instead the* function RedisEstimateRSS() that is a much faster (and less precise)* version of the function. */#if defined(HAVE_PROC_STAT) #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h>size_t zmalloc_get_rss(void) {int page = sysconf(_SC_PAGESIZE);size_t rss;char buf[4096];char filename[256];int fd, count;char *p, *x;snprintf(filename,256,"/proc/%d/stat",getpid());if ((fd = open(filename,O_RDONLY)) == -1) return 0;if (read(fd,buf,4096) <= 0) {close(fd);return 0;}close(fd);p = buf;count = 23; /* RSS is the 24th field in /proc/<pid>/stat */while(p && count--) {p = strchr(p,' ');if (p) p++;}if (!p) return 0;x = strchr(p,' ');if (!x) return 0;*x = '\0';rss = strtoll(p,NULL,10);rss *= page;return rss; } #elif defined(HAVE_TASKINFO) #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <sys/types.h> #include <sys/sysctl.h> #include <mach/task.h> #include <mach/mach_init.h>size_t zmalloc_get_rss(void) {task_t task = MACH_PORT_NULL;struct task_basic_info t_info;mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT;if (task_for_pid(current_task(), getpid(), &task) != KERN_SUCCESS)return 0;task_info(task, TASK_BASIC_INFO, (task_info_t)&t_info, &t_info_count);return t_info.resident_size; } #else size_t zmalloc_get_rss(void) {/* If we can't get the RSS in an OS-specific way for this system just* return the memory usage we estimated in zmalloc()..** Fragmentation will appear to be always 1 (no fragmentation)* of course... */return zmalloc_used_memory(); } #endif/* Fragmentation = RSS / allocated-bytes */ float zmalloc_get_fragmentation_ratio(size_t rss) {return (float)rss/zmalloc_used_memory(); }/* Get the sum of the specified field (converted form kb to bytes) in* /proc/self/smaps. The field must be specified with trailing ":" as it* apperas in the smaps output.** Example: zmalloc_get_smap_bytes_by_field("Rss:");*/ #if defined(HAVE_PROC_SMAPS) size_t zmalloc_get_smap_bytes_by_field(char *field) {char line[1024];size_t bytes = 0;FILE *fp = fopen("/proc/self/smaps","r");int flen = strlen(field);if (!fp) return 0;while(fgets(line,sizeof(line),fp) != NULL) {if (strncmp(line,field,flen) == 0) {char *p = strchr(line,'k');if (p) {*p = '\0';bytes += strtol(line+flen,NULL,10) * 1024;}}}fclose(fp);return bytes; } #else size_t zmalloc_get_smap_bytes_by_field(char *field) {((void) field);return 0; } #endifsize_t zmalloc_get_private_dirty(void) {return zmalloc_get_smap_bytes_by_field("Private_Dirty:"); }

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