xref: /f-stack/app/redis-5.0.5/src/zmalloc.c (revision 572c4311)
1 /* zmalloc - total amount of allocated memory aware version of malloc()
2  *
3  * Copyright (c) 2009-2010, Salvatore Sanfilippo <antirez at gmail dot com>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  *   * Redistributions of source code must retain the above copyright notice,
10  *     this list of conditions and the following disclaimer.
11  *   * Redistributions in binary form must reproduce the above copyright
12  *     notice, this list of conditions and the following disclaimer in the
13  *     documentation and/or other materials provided with the distribution.
14  *   * Neither the name of Redis nor the names of its contributors may be used
15  *     to endorse or promote products derived from this software without
16  *     specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <stdint.h>
34 
35 /* This function provide us access to the original libc free(). This is useful
36  * for instance to free results obtained by backtrace_symbols(). We need
37  * to define this function before including zmalloc.h that may shadow the
38  * free implementation if we use jemalloc or another non standard allocator. */
zlibc_free(void * ptr)39 void zlibc_free(void *ptr) {
40     free(ptr);
41 }
42 
43 #include <string.h>
44 #include <pthread.h>
45 #include "config.h"
46 #include "zmalloc.h"
47 #include "atomicvar.h"
48 
49 #ifdef HAVE_MALLOC_SIZE
50 #define PREFIX_SIZE (0)
51 #else
52 #if defined(__sun) || defined(__sparc) || defined(__sparc__)
53 #define PREFIX_SIZE (sizeof(long long))
54 #else
55 #define PREFIX_SIZE (sizeof(size_t))
56 #endif
57 #endif
58 
59 /* Explicitly override malloc/free etc when using tcmalloc. */
60 #if defined(USE_TCMALLOC)
61 #define malloc(size) tc_malloc(size)
62 #define calloc(count,size) tc_calloc(count,size)
63 #define realloc(ptr,size) tc_realloc(ptr,size)
64 #define free(ptr) tc_free(ptr)
65 #elif defined(USE_JEMALLOC)
66 #define malloc(size) je_malloc(size)
67 #define calloc(count,size) je_calloc(count,size)
68 #define realloc(ptr,size) je_realloc(ptr,size)
69 #define free(ptr) je_free(ptr)
70 #define mallocx(size,flags) je_mallocx(size,flags)
71 #define dallocx(ptr,flags) je_dallocx(ptr,flags)
72 #endif
73 
74 #define update_zmalloc_stat_alloc(__n) do { \
75     size_t _n = (__n); \
76     if (_n&(sizeof(long)-1)) _n += sizeof(long)-(_n&(sizeof(long)-1)); \
77     atomicIncr(used_memory,__n); \
78 } while(0)
79 
80 #define update_zmalloc_stat_free(__n) do { \
81     size_t _n = (__n); \
82     if (_n&(sizeof(long)-1)) _n += sizeof(long)-(_n&(sizeof(long)-1)); \
83     atomicDecr(used_memory,__n); \
84 } while(0)
85 
86 static size_t used_memory = 0;
87 pthread_mutex_t used_memory_mutex = PTHREAD_MUTEX_INITIALIZER;
88 
zmalloc_default_oom(size_t size)89 static void zmalloc_default_oom(size_t size) {
90     fprintf(stderr, "zmalloc: Out of memory trying to allocate %zu bytes\n",
91         size);
92     fflush(stderr);
93     abort();
94 }
95 
96 static void (*zmalloc_oom_handler)(size_t) = zmalloc_default_oom;
97 
zmalloc(size_t size)98 void *zmalloc(size_t size) {
99     void *ptr = malloc(size+PREFIX_SIZE);
100 
101     if (!ptr) zmalloc_oom_handler(size);
102 #ifdef HAVE_MALLOC_SIZE
103     update_zmalloc_stat_alloc(zmalloc_size(ptr));
104     return ptr;
105 #else
106     *((size_t*)ptr) = size;
107     update_zmalloc_stat_alloc(size+PREFIX_SIZE);
108     return (char*)ptr+PREFIX_SIZE;
109 #endif
110 }
111 
112 /* Allocation and free functions that bypass the thread cache
113  * and go straight to the allocator arena bins.
114  * Currently implemented only for jemalloc. Used for online defragmentation. */
115 #ifdef HAVE_DEFRAG
zmalloc_no_tcache(size_t size)116 void *zmalloc_no_tcache(size_t size) {
117     void *ptr = mallocx(size+PREFIX_SIZE, MALLOCX_TCACHE_NONE);
118     if (!ptr) zmalloc_oom_handler(size);
119     update_zmalloc_stat_alloc(zmalloc_size(ptr));
120     return ptr;
121 }
122 
zfree_no_tcache(void * ptr)123 void zfree_no_tcache(void *ptr) {
124     if (ptr == NULL) return;
125     update_zmalloc_stat_free(zmalloc_size(ptr));
126     dallocx(ptr, MALLOCX_TCACHE_NONE);
127 }
128 #endif
129 
zcalloc(size_t size)130 void *zcalloc(size_t size) {
131     void *ptr = calloc(1, size+PREFIX_SIZE);
132 
133     if (!ptr) zmalloc_oom_handler(size);
134 #ifdef HAVE_MALLOC_SIZE
135     update_zmalloc_stat_alloc(zmalloc_size(ptr));
136     return ptr;
137 #else
138     *((size_t*)ptr) = size;
139     update_zmalloc_stat_alloc(size+PREFIX_SIZE);
140     return (char*)ptr+PREFIX_SIZE;
141 #endif
142 }
143 
zrealloc(void * ptr,size_t size)144 void *zrealloc(void *ptr, size_t size) {
145 #ifndef HAVE_MALLOC_SIZE
146     void *realptr;
147 #endif
148     size_t oldsize;
149     void *newptr;
150 
151     if (ptr == NULL) return zmalloc(size);
152 #ifdef HAVE_MALLOC_SIZE
153     oldsize = zmalloc_size(ptr);
154     newptr = realloc(ptr,size);
155     if (!newptr) zmalloc_oom_handler(size);
156 
157     update_zmalloc_stat_free(oldsize);
158     update_zmalloc_stat_alloc(zmalloc_size(newptr));
159     return newptr;
160 #else
161     realptr = (char*)ptr-PREFIX_SIZE;
162     oldsize = *((size_t*)realptr);
163     newptr = realloc(realptr,size+PREFIX_SIZE);
164     if (!newptr) zmalloc_oom_handler(size);
165 
166     *((size_t*)newptr) = size;
167     update_zmalloc_stat_free(oldsize+PREFIX_SIZE);
168     update_zmalloc_stat_alloc(size+PREFIX_SIZE);
169     return (char*)newptr+PREFIX_SIZE;
170 #endif
171 }
172 
173 /* Provide zmalloc_size() for systems where this function is not provided by
174  * malloc itself, given that in that case we store a header with this
175  * information as the first bytes of every allocation. */
176 #ifndef HAVE_MALLOC_SIZE
zmalloc_size(void * ptr)177 size_t zmalloc_size(void *ptr) {
178     void *realptr = (char*)ptr-PREFIX_SIZE;
179     size_t size = *((size_t*)realptr);
180     /* Assume at least that all the allocations are padded at sizeof(long) by
181      * the underlying allocator. */
182     if (size&(sizeof(long)-1)) size += sizeof(long)-(size&(sizeof(long)-1));
183     return size+PREFIX_SIZE;
184 }
zmalloc_usable(void * ptr)185 size_t zmalloc_usable(void *ptr) {
186     return zmalloc_size(ptr)-PREFIX_SIZE;
187 }
188 #endif
189 
zfree(void * ptr)190 void zfree(void *ptr) {
191 #ifndef HAVE_MALLOC_SIZE
192     void *realptr;
193     size_t oldsize;
194 #endif
195 
196     if (ptr == NULL) return;
197 #ifdef HAVE_MALLOC_SIZE
198     update_zmalloc_stat_free(zmalloc_size(ptr));
199     free(ptr);
200 #else
201     realptr = (char*)ptr-PREFIX_SIZE;
202     oldsize = *((size_t*)realptr);
203     update_zmalloc_stat_free(oldsize+PREFIX_SIZE);
204     free(realptr);
205 #endif
206 }
207 
zstrdup(const char * s)208 char *zstrdup(const char *s) {
209     size_t l = strlen(s)+1;
210     char *p = zmalloc(l);
211 
212     memcpy(p,s,l);
213     return p;
214 }
215 
zmalloc_used_memory(void)216 size_t zmalloc_used_memory(void) {
217     size_t um;
218     atomicGet(used_memory,um);
219     return um;
220 }
221 
zmalloc_set_oom_handler(void (* oom_handler)(size_t))222 void zmalloc_set_oom_handler(void (*oom_handler)(size_t)) {
223     zmalloc_oom_handler = oom_handler;
224 }
225 
226 /* Get the RSS information in an OS-specific way.
227  *
228  * WARNING: the function zmalloc_get_rss() is not designed to be fast
229  * and may not be called in the busy loops where Redis tries to release
230  * memory expiring or swapping out objects.
231  *
232  * For this kind of "fast RSS reporting" usages use instead the
233  * function RedisEstimateRSS() that is a much faster (and less precise)
234  * version of the function. */
235 
236 #if defined(HAVE_PROC_STAT)
237 #include <unistd.h>
238 #include <sys/types.h>
239 #include <sys/stat.h>
240 #include <fcntl.h>
241 
zmalloc_get_rss(void)242 size_t zmalloc_get_rss(void) {
243     int page = sysconf(_SC_PAGESIZE);
244     size_t rss;
245     char buf[4096];
246     char filename[256];
247     int fd, count;
248     char *p, *x;
249 
250     snprintf(filename,256,"/proc/%d/stat",getpid());
251     if ((fd = open(filename,O_RDONLY)) == -1) return 0;
252     if (read(fd,buf,4096) <= 0) {
253         close(fd);
254         return 0;
255     }
256     close(fd);
257 
258     p = buf;
259     count = 23; /* RSS is the 24th field in /proc/<pid>/stat */
260     while(p && count--) {
261         p = strchr(p,' ');
262         if (p) p++;
263     }
264     if (!p) return 0;
265     x = strchr(p,' ');
266     if (!x) return 0;
267     *x = '\0';
268 
269     rss = strtoll(p,NULL,10);
270     rss *= page;
271     return rss;
272 }
273 #elif defined(HAVE_TASKINFO)
274 #include <unistd.h>
275 #include <stdio.h>
276 #include <stdlib.h>
277 #include <sys/types.h>
278 #include <sys/sysctl.h>
279 #include <mach/task.h>
280 #include <mach/mach_init.h>
281 
zmalloc_get_rss(void)282 size_t zmalloc_get_rss(void) {
283     task_t task = MACH_PORT_NULL;
284     struct task_basic_info t_info;
285     mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT;
286 
287     if (task_for_pid(current_task(), getpid(), &task) != KERN_SUCCESS)
288         return 0;
289     task_info(task, TASK_BASIC_INFO, (task_info_t)&t_info, &t_info_count);
290 
291     return t_info.resident_size;
292 }
293 #else
zmalloc_get_rss(void)294 size_t zmalloc_get_rss(void) {
295     /* If we can't get the RSS in an OS-specific way for this system just
296      * return the memory usage we estimated in zmalloc()..
297      *
298      * Fragmentation will appear to be always 1 (no fragmentation)
299      * of course... */
300     return zmalloc_used_memory();
301 }
302 #endif
303 
304 #if defined(USE_JEMALLOC)
zmalloc_get_allocator_info(size_t * allocated,size_t * active,size_t * resident)305 int zmalloc_get_allocator_info(size_t *allocated,
306                                size_t *active,
307                                size_t *resident) {
308     uint64_t epoch = 1;
309     size_t sz;
310     *allocated = *resident = *active = 0;
311     /* Update the statistics cached by mallctl. */
312     sz = sizeof(epoch);
313     je_mallctl("epoch", &epoch, &sz, &epoch, sz);
314     sz = sizeof(size_t);
315     /* Unlike RSS, this does not include RSS from shared libraries and other non
316      * heap mappings. */
317     je_mallctl("stats.resident", resident, &sz, NULL, 0);
318     /* Unlike resident, this doesn't not include the pages jemalloc reserves
319      * for re-use (purge will clean that). */
320     je_mallctl("stats.active", active, &sz, NULL, 0);
321     /* Unlike zmalloc_used_memory, this matches the stats.resident by taking
322      * into account all allocations done by this process (not only zmalloc). */
323     je_mallctl("stats.allocated", allocated, &sz, NULL, 0);
324     return 1;
325 }
326 #else
zmalloc_get_allocator_info(size_t * allocated,size_t * active,size_t * resident)327 int zmalloc_get_allocator_info(size_t *allocated,
328                                size_t *active,
329                                size_t *resident) {
330     *allocated = *resident = *active = 0;
331     return 1;
332 }
333 #endif
334 
335 /* Get the sum of the specified field (converted form kb to bytes) in
336  * /proc/self/smaps. The field must be specified with trailing ":" as it
337  * apperas in the smaps output.
338  *
339  * If a pid is specified, the information is extracted for such a pid,
340  * otherwise if pid is -1 the information is reported is about the
341  * current process.
342  *
343  * Example: zmalloc_get_smap_bytes_by_field("Rss:",-1);
344  */
345 #if defined(HAVE_PROC_SMAPS)
zmalloc_get_smap_bytes_by_field(char * field,long pid)346 size_t zmalloc_get_smap_bytes_by_field(char *field, long pid) {
347     char line[1024];
348     size_t bytes = 0;
349     int flen = strlen(field);
350     FILE *fp;
351 
352     if (pid == -1) {
353         fp = fopen("/proc/self/smaps","r");
354     } else {
355         char filename[128];
356         snprintf(filename,sizeof(filename),"/proc/%ld/smaps",pid);
357         fp = fopen(filename,"r");
358     }
359 
360     if (!fp) return 0;
361     while(fgets(line,sizeof(line),fp) != NULL) {
362         if (strncmp(line,field,flen) == 0) {
363             char *p = strchr(line,'k');
364             if (p) {
365                 *p = '\0';
366                 bytes += strtol(line+flen,NULL,10) * 1024;
367             }
368         }
369     }
370     fclose(fp);
371     return bytes;
372 }
373 #else
zmalloc_get_smap_bytes_by_field(char * field,long pid)374 size_t zmalloc_get_smap_bytes_by_field(char *field, long pid) {
375     ((void) field);
376     ((void) pid);
377     return 0;
378 }
379 #endif
380 
zmalloc_get_private_dirty(long pid)381 size_t zmalloc_get_private_dirty(long pid) {
382     return zmalloc_get_smap_bytes_by_field("Private_Dirty:",pid);
383 }
384 
385 /* Returns the size of physical memory (RAM) in bytes.
386  * It looks ugly, but this is the cleanest way to achieve cross platform results.
387  * Cleaned up from:
388  *
389  * http://nadeausoftware.com/articles/2012/09/c_c_tip_how_get_physical_memory_size_system
390  *
391  * Note that this function:
392  * 1) Was released under the following CC attribution license:
393  *    http://creativecommons.org/licenses/by/3.0/deed.en_US.
394  * 2) Was originally implemented by David Robert Nadeau.
395  * 3) Was modified for Redis by Matt Stancliff.
396  * 4) This note exists in order to comply with the original license.
397  */
zmalloc_get_memory_size(void)398 size_t zmalloc_get_memory_size(void) {
399 #if defined(__unix__) || defined(__unix) || defined(unix) || \
400     (defined(__APPLE__) && defined(__MACH__))
401 #if defined(CTL_HW) && (defined(HW_MEMSIZE) || defined(HW_PHYSMEM64))
402     int mib[2];
403     mib[0] = CTL_HW;
404 #if defined(HW_MEMSIZE)
405     mib[1] = HW_MEMSIZE;            /* OSX. --------------------- */
406 #elif defined(HW_PHYSMEM64)
407     mib[1] = HW_PHYSMEM64;          /* NetBSD, OpenBSD. --------- */
408 #endif
409     int64_t size = 0;               /* 64-bit */
410     size_t len = sizeof(size);
411     if (sysctl( mib, 2, &size, &len, NULL, 0) == 0)
412         return (size_t)size;
413     return 0L;          /* Failed? */
414 
415 #elif defined(_SC_PHYS_PAGES) && defined(_SC_PAGESIZE)
416     /* FreeBSD, Linux, OpenBSD, and Solaris. -------------------- */
417     return (size_t)sysconf(_SC_PHYS_PAGES) * (size_t)sysconf(_SC_PAGESIZE);
418 
419 #elif defined(CTL_HW) && (defined(HW_PHYSMEM) || defined(HW_REALMEM))
420     /* DragonFly BSD, FreeBSD, NetBSD, OpenBSD, and OSX. -------- */
421     int mib[2];
422     mib[0] = CTL_HW;
423 #if defined(HW_REALMEM)
424     mib[1] = HW_REALMEM;        /* FreeBSD. ----------------- */
425 #elif defined(HW_PHYSMEM)
426     mib[1] = HW_PHYSMEM;        /* Others. ------------------ */
427 #endif
428     unsigned int size = 0;      /* 32-bit */
429     size_t len = sizeof(size);
430     if (sysctl(mib, 2, &size, &len, NULL, 0) == 0)
431         return (size_t)size;
432     return 0L;          /* Failed? */
433 #else
434     return 0L;          /* Unknown method to get the data. */
435 #endif
436 #else
437     return 0L;          /* Unknown OS. */
438 #endif
439 }
440 
441 #ifdef REDIS_TEST
442 #define UNUSED(x) ((void)(x))
zmalloc_test(int argc,char ** argv)443 int zmalloc_test(int argc, char **argv) {
444     void *ptr;
445 
446     UNUSED(argc);
447     UNUSED(argv);
448     printf("Initial used memory: %zu\n", zmalloc_used_memory());
449     ptr = zmalloc(123);
450     printf("Allocated 123 bytes; used: %zu\n", zmalloc_used_memory());
451     ptr = zrealloc(ptr, 456);
452     printf("Reallocated to 456 bytes; used: %zu\n", zmalloc_used_memory());
453     zfree(ptr);
454     printf("Freed pointer; used: %zu\n", zmalloc_used_memory());
455     return 0;
456 }
457 #endif
458