Merge branch 'fixes-wakeupgen' into fixes
[platform/adaptation/renesas_rcar/renesas_kernel.git] / tools / perf / builtin-kmem.c
1 #include "builtin.h"
2 #include "perf.h"
3
4 #include "util/util.h"
5 #include "util/cache.h"
6 #include "util/symbol.h"
7 #include "util/thread.h"
8 #include "util/header.h"
9 #include "util/session.h"
10 #include "util/tool.h"
11
12 #include "util/parse-options.h"
13 #include "util/trace-event.h"
14
15 #include "util/debug.h"
16
17 #include <linux/rbtree.h>
18
19 struct alloc_stat;
20 typedef int (*sort_fn_t)(struct alloc_stat *, struct alloc_stat *);
21
22 static const char               *input_name;
23
24 static int                      alloc_flag;
25 static int                      caller_flag;
26
27 static int                      alloc_lines = -1;
28 static int                      caller_lines = -1;
29
30 static bool                     raw_ip;
31
32 static char                     default_sort_order[] = "frag,hit,bytes";
33
34 static int                      *cpunode_map;
35 static int                      max_cpu_num;
36
37 struct alloc_stat {
38         u64     call_site;
39         u64     ptr;
40         u64     bytes_req;
41         u64     bytes_alloc;
42         u32     hit;
43         u32     pingpong;
44
45         short   alloc_cpu;
46
47         struct rb_node node;
48 };
49
50 static struct rb_root root_alloc_stat;
51 static struct rb_root root_alloc_sorted;
52 static struct rb_root root_caller_stat;
53 static struct rb_root root_caller_sorted;
54
55 static unsigned long total_requested, total_allocated;
56 static unsigned long nr_allocs, nr_cross_allocs;
57
58 #define PATH_SYS_NODE   "/sys/devices/system/node"
59
60 struct perf_kmem {
61         struct perf_tool    tool;
62         struct perf_session *session;
63 };
64
65 static void init_cpunode_map(void)
66 {
67         FILE *fp;
68         int i;
69
70         fp = fopen("/sys/devices/system/cpu/kernel_max", "r");
71         if (!fp) {
72                 max_cpu_num = 4096;
73                 return;
74         }
75
76         if (fscanf(fp, "%d", &max_cpu_num) < 1)
77                 die("Failed to read 'kernel_max' from sysfs");
78         max_cpu_num++;
79
80         cpunode_map = calloc(max_cpu_num, sizeof(int));
81         if (!cpunode_map)
82                 die("calloc");
83         for (i = 0; i < max_cpu_num; i++)
84                 cpunode_map[i] = -1;
85         fclose(fp);
86 }
87
88 static void setup_cpunode_map(void)
89 {
90         struct dirent *dent1, *dent2;
91         DIR *dir1, *dir2;
92         unsigned int cpu, mem;
93         char buf[PATH_MAX];
94
95         init_cpunode_map();
96
97         dir1 = opendir(PATH_SYS_NODE);
98         if (!dir1)
99                 return;
100
101         while ((dent1 = readdir(dir1)) != NULL) {
102                 if (dent1->d_type != DT_DIR ||
103                     sscanf(dent1->d_name, "node%u", &mem) < 1)
104                         continue;
105
106                 snprintf(buf, PATH_MAX, "%s/%s", PATH_SYS_NODE, dent1->d_name);
107                 dir2 = opendir(buf);
108                 if (!dir2)
109                         continue;
110                 while ((dent2 = readdir(dir2)) != NULL) {
111                         if (dent2->d_type != DT_LNK ||
112                             sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
113                                 continue;
114                         cpunode_map[cpu] = mem;
115                 }
116                 closedir(dir2);
117         }
118         closedir(dir1);
119 }
120
121 static void insert_alloc_stat(unsigned long call_site, unsigned long ptr,
122                               int bytes_req, int bytes_alloc, int cpu)
123 {
124         struct rb_node **node = &root_alloc_stat.rb_node;
125         struct rb_node *parent = NULL;
126         struct alloc_stat *data = NULL;
127
128         while (*node) {
129                 parent = *node;
130                 data = rb_entry(*node, struct alloc_stat, node);
131
132                 if (ptr > data->ptr)
133                         node = &(*node)->rb_right;
134                 else if (ptr < data->ptr)
135                         node = &(*node)->rb_left;
136                 else
137                         break;
138         }
139
140         if (data && data->ptr == ptr) {
141                 data->hit++;
142                 data->bytes_req += bytes_req;
143                 data->bytes_alloc += bytes_alloc;
144         } else {
145                 data = malloc(sizeof(*data));
146                 if (!data)
147                         die("malloc");
148                 data->ptr = ptr;
149                 data->pingpong = 0;
150                 data->hit = 1;
151                 data->bytes_req = bytes_req;
152                 data->bytes_alloc = bytes_alloc;
153
154                 rb_link_node(&data->node, parent, node);
155                 rb_insert_color(&data->node, &root_alloc_stat);
156         }
157         data->call_site = call_site;
158         data->alloc_cpu = cpu;
159 }
160
161 static void insert_caller_stat(unsigned long call_site,
162                               int bytes_req, int bytes_alloc)
163 {
164         struct rb_node **node = &root_caller_stat.rb_node;
165         struct rb_node *parent = NULL;
166         struct alloc_stat *data = NULL;
167
168         while (*node) {
169                 parent = *node;
170                 data = rb_entry(*node, struct alloc_stat, node);
171
172                 if (call_site > data->call_site)
173                         node = &(*node)->rb_right;
174                 else if (call_site < data->call_site)
175                         node = &(*node)->rb_left;
176                 else
177                         break;
178         }
179
180         if (data && data->call_site == call_site) {
181                 data->hit++;
182                 data->bytes_req += bytes_req;
183                 data->bytes_alloc += bytes_alloc;
184         } else {
185                 data = malloc(sizeof(*data));
186                 if (!data)
187                         die("malloc");
188                 data->call_site = call_site;
189                 data->pingpong = 0;
190                 data->hit = 1;
191                 data->bytes_req = bytes_req;
192                 data->bytes_alloc = bytes_alloc;
193
194                 rb_link_node(&data->node, parent, node);
195                 rb_insert_color(&data->node, &root_caller_stat);
196         }
197 }
198
199 static void process_alloc_event(void *data,
200                                 struct event_format *event,
201                                 int cpu,
202                                 u64 timestamp __used,
203                                 struct thread *thread __used,
204                                 int node)
205 {
206         unsigned long call_site;
207         unsigned long ptr;
208         int bytes_req;
209         int bytes_alloc;
210         int node1, node2;
211
212         ptr = raw_field_value(event, "ptr", data);
213         call_site = raw_field_value(event, "call_site", data);
214         bytes_req = raw_field_value(event, "bytes_req", data);
215         bytes_alloc = raw_field_value(event, "bytes_alloc", data);
216
217         insert_alloc_stat(call_site, ptr, bytes_req, bytes_alloc, cpu);
218         insert_caller_stat(call_site, bytes_req, bytes_alloc);
219
220         total_requested += bytes_req;
221         total_allocated += bytes_alloc;
222
223         if (node) {
224                 node1 = cpunode_map[cpu];
225                 node2 = raw_field_value(event, "node", data);
226                 if (node1 != node2)
227                         nr_cross_allocs++;
228         }
229         nr_allocs++;
230 }
231
232 static int ptr_cmp(struct alloc_stat *, struct alloc_stat *);
233 static int callsite_cmp(struct alloc_stat *, struct alloc_stat *);
234
235 static struct alloc_stat *search_alloc_stat(unsigned long ptr,
236                                             unsigned long call_site,
237                                             struct rb_root *root,
238                                             sort_fn_t sort_fn)
239 {
240         struct rb_node *node = root->rb_node;
241         struct alloc_stat key = { .ptr = ptr, .call_site = call_site };
242
243         while (node) {
244                 struct alloc_stat *data;
245                 int cmp;
246
247                 data = rb_entry(node, struct alloc_stat, node);
248
249                 cmp = sort_fn(&key, data);
250                 if (cmp < 0)
251                         node = node->rb_left;
252                 else if (cmp > 0)
253                         node = node->rb_right;
254                 else
255                         return data;
256         }
257         return NULL;
258 }
259
260 static void process_free_event(void *data,
261                                struct event_format *event,
262                                int cpu,
263                                u64 timestamp __used,
264                                struct thread *thread __used)
265 {
266         unsigned long ptr;
267         struct alloc_stat *s_alloc, *s_caller;
268
269         ptr = raw_field_value(event, "ptr", data);
270
271         s_alloc = search_alloc_stat(ptr, 0, &root_alloc_stat, ptr_cmp);
272         if (!s_alloc)
273                 return;
274
275         if (cpu != s_alloc->alloc_cpu) {
276                 s_alloc->pingpong++;
277
278                 s_caller = search_alloc_stat(0, s_alloc->call_site,
279                                              &root_caller_stat, callsite_cmp);
280                 assert(s_caller);
281                 s_caller->pingpong++;
282         }
283         s_alloc->alloc_cpu = -1;
284 }
285
286 static void process_raw_event(struct perf_tool *tool,
287                               union perf_event *raw_event __used, void *data,
288                               int cpu, u64 timestamp, struct thread *thread)
289 {
290         struct perf_kmem *kmem = container_of(tool, struct perf_kmem, tool);
291         struct event_format *event;
292         int type;
293
294         type = trace_parse_common_type(kmem->session->pevent, data);
295         event = pevent_find_event(kmem->session->pevent, type);
296
297         if (!strcmp(event->name, "kmalloc") ||
298             !strcmp(event->name, "kmem_cache_alloc")) {
299                 process_alloc_event(data, event, cpu, timestamp, thread, 0);
300                 return;
301         }
302
303         if (!strcmp(event->name, "kmalloc_node") ||
304             !strcmp(event->name, "kmem_cache_alloc_node")) {
305                 process_alloc_event(data, event, cpu, timestamp, thread, 1);
306                 return;
307         }
308
309         if (!strcmp(event->name, "kfree") ||
310             !strcmp(event->name, "kmem_cache_free")) {
311                 process_free_event(data, event, cpu, timestamp, thread);
312                 return;
313         }
314 }
315
316 static int process_sample_event(struct perf_tool *tool,
317                                 union perf_event *event,
318                                 struct perf_sample *sample,
319                                 struct perf_evsel *evsel __used,
320                                 struct machine *machine)
321 {
322         struct thread *thread = machine__findnew_thread(machine, event->ip.pid);
323
324         if (thread == NULL) {
325                 pr_debug("problem processing %d event, skipping it.\n",
326                          event->header.type);
327                 return -1;
328         }
329
330         dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
331
332         process_raw_event(tool, event, sample->raw_data, sample->cpu,
333                           sample->time, thread);
334
335         return 0;
336 }
337
338 static struct perf_kmem perf_kmem = {
339         .tool = {
340                 .sample                 = process_sample_event,
341                 .comm                   = perf_event__process_comm,
342                 .ordered_samples        = true,
343         },
344 };
345
346 static double fragmentation(unsigned long n_req, unsigned long n_alloc)
347 {
348         if (n_alloc == 0)
349                 return 0.0;
350         else
351                 return 100.0 - (100.0 * n_req / n_alloc);
352 }
353
354 static void __print_result(struct rb_root *root, struct perf_session *session,
355                            int n_lines, int is_caller)
356 {
357         struct rb_node *next;
358         struct machine *machine;
359
360         printf("%.102s\n", graph_dotted_line);
361         printf(" %-34s |",  is_caller ? "Callsite": "Alloc Ptr");
362         printf(" Total_alloc/Per | Total_req/Per   | Hit      | Ping-pong | Frag\n");
363         printf("%.102s\n", graph_dotted_line);
364
365         next = rb_first(root);
366
367         machine = perf_session__find_host_machine(session);
368         if (!machine) {
369                 pr_err("__print_result: couldn't find kernel information\n");
370                 return;
371         }
372         while (next && n_lines--) {
373                 struct alloc_stat *data = rb_entry(next, struct alloc_stat,
374                                                    node);
375                 struct symbol *sym = NULL;
376                 struct map *map;
377                 char buf[BUFSIZ];
378                 u64 addr;
379
380                 if (is_caller) {
381                         addr = data->call_site;
382                         if (!raw_ip)
383                                 sym = machine__find_kernel_function(machine, addr, &map, NULL);
384                 } else
385                         addr = data->ptr;
386
387                 if (sym != NULL)
388                         snprintf(buf, sizeof(buf), "%s+%" PRIx64 "", sym->name,
389                                  addr - map->unmap_ip(map, sym->start));
390                 else
391                         snprintf(buf, sizeof(buf), "%#" PRIx64 "", addr);
392                 printf(" %-34s |", buf);
393
394                 printf(" %9llu/%-5lu | %9llu/%-5lu | %8lu | %8lu | %6.3f%%\n",
395                        (unsigned long long)data->bytes_alloc,
396                        (unsigned long)data->bytes_alloc / data->hit,
397                        (unsigned long long)data->bytes_req,
398                        (unsigned long)data->bytes_req / data->hit,
399                        (unsigned long)data->hit,
400                        (unsigned long)data->pingpong,
401                        fragmentation(data->bytes_req, data->bytes_alloc));
402
403                 next = rb_next(next);
404         }
405
406         if (n_lines == -1)
407                 printf(" ...                                | ...             | ...             | ...    | ...      | ...   \n");
408
409         printf("%.102s\n", graph_dotted_line);
410 }
411
412 static void print_summary(void)
413 {
414         printf("\nSUMMARY\n=======\n");
415         printf("Total bytes requested: %lu\n", total_requested);
416         printf("Total bytes allocated: %lu\n", total_allocated);
417         printf("Total bytes wasted on internal fragmentation: %lu\n",
418                total_allocated - total_requested);
419         printf("Internal fragmentation: %f%%\n",
420                fragmentation(total_requested, total_allocated));
421         printf("Cross CPU allocations: %lu/%lu\n", nr_cross_allocs, nr_allocs);
422 }
423
424 static void print_result(struct perf_session *session)
425 {
426         if (caller_flag)
427                 __print_result(&root_caller_sorted, session, caller_lines, 1);
428         if (alloc_flag)
429                 __print_result(&root_alloc_sorted, session, alloc_lines, 0);
430         print_summary();
431 }
432
433 struct sort_dimension {
434         const char              name[20];
435         sort_fn_t               cmp;
436         struct list_head        list;
437 };
438
439 static LIST_HEAD(caller_sort);
440 static LIST_HEAD(alloc_sort);
441
442 static void sort_insert(struct rb_root *root, struct alloc_stat *data,
443                         struct list_head *sort_list)
444 {
445         struct rb_node **new = &(root->rb_node);
446         struct rb_node *parent = NULL;
447         struct sort_dimension *sort;
448
449         while (*new) {
450                 struct alloc_stat *this;
451                 int cmp = 0;
452
453                 this = rb_entry(*new, struct alloc_stat, node);
454                 parent = *new;
455
456                 list_for_each_entry(sort, sort_list, list) {
457                         cmp = sort->cmp(data, this);
458                         if (cmp)
459                                 break;
460                 }
461
462                 if (cmp > 0)
463                         new = &((*new)->rb_left);
464                 else
465                         new = &((*new)->rb_right);
466         }
467
468         rb_link_node(&data->node, parent, new);
469         rb_insert_color(&data->node, root);
470 }
471
472 static void __sort_result(struct rb_root *root, struct rb_root *root_sorted,
473                           struct list_head *sort_list)
474 {
475         struct rb_node *node;
476         struct alloc_stat *data;
477
478         for (;;) {
479                 node = rb_first(root);
480                 if (!node)
481                         break;
482
483                 rb_erase(node, root);
484                 data = rb_entry(node, struct alloc_stat, node);
485                 sort_insert(root_sorted, data, sort_list);
486         }
487 }
488
489 static void sort_result(void)
490 {
491         __sort_result(&root_alloc_stat, &root_alloc_sorted, &alloc_sort);
492         __sort_result(&root_caller_stat, &root_caller_sorted, &caller_sort);
493 }
494
495 static int __cmd_kmem(void)
496 {
497         int err = -EINVAL;
498         struct perf_session *session;
499
500         session = perf_session__new(input_name, O_RDONLY, 0, false,
501                                     &perf_kmem.tool);
502         if (session == NULL)
503                 return -ENOMEM;
504
505         perf_kmem.session = session;
506
507         if (perf_session__create_kernel_maps(session) < 0)
508                 goto out_delete;
509
510         if (!perf_session__has_traces(session, "kmem record"))
511                 goto out_delete;
512
513         setup_pager();
514         err = perf_session__process_events(session, &perf_kmem.tool);
515         if (err != 0)
516                 goto out_delete;
517         sort_result();
518         print_result(session);
519 out_delete:
520         perf_session__delete(session);
521         return err;
522 }
523
524 static const char * const kmem_usage[] = {
525         "perf kmem [<options>] {record|stat}",
526         NULL
527 };
528
529 static int ptr_cmp(struct alloc_stat *l, struct alloc_stat *r)
530 {
531         if (l->ptr < r->ptr)
532                 return -1;
533         else if (l->ptr > r->ptr)
534                 return 1;
535         return 0;
536 }
537
538 static struct sort_dimension ptr_sort_dimension = {
539         .name   = "ptr",
540         .cmp    = ptr_cmp,
541 };
542
543 static int callsite_cmp(struct alloc_stat *l, struct alloc_stat *r)
544 {
545         if (l->call_site < r->call_site)
546                 return -1;
547         else if (l->call_site > r->call_site)
548                 return 1;
549         return 0;
550 }
551
552 static struct sort_dimension callsite_sort_dimension = {
553         .name   = "callsite",
554         .cmp    = callsite_cmp,
555 };
556
557 static int hit_cmp(struct alloc_stat *l, struct alloc_stat *r)
558 {
559         if (l->hit < r->hit)
560                 return -1;
561         else if (l->hit > r->hit)
562                 return 1;
563         return 0;
564 }
565
566 static struct sort_dimension hit_sort_dimension = {
567         .name   = "hit",
568         .cmp    = hit_cmp,
569 };
570
571 static int bytes_cmp(struct alloc_stat *l, struct alloc_stat *r)
572 {
573         if (l->bytes_alloc < r->bytes_alloc)
574                 return -1;
575         else if (l->bytes_alloc > r->bytes_alloc)
576                 return 1;
577         return 0;
578 }
579
580 static struct sort_dimension bytes_sort_dimension = {
581         .name   = "bytes",
582         .cmp    = bytes_cmp,
583 };
584
585 static int frag_cmp(struct alloc_stat *l, struct alloc_stat *r)
586 {
587         double x, y;
588
589         x = fragmentation(l->bytes_req, l->bytes_alloc);
590         y = fragmentation(r->bytes_req, r->bytes_alloc);
591
592         if (x < y)
593                 return -1;
594         else if (x > y)
595                 return 1;
596         return 0;
597 }
598
599 static struct sort_dimension frag_sort_dimension = {
600         .name   = "frag",
601         .cmp    = frag_cmp,
602 };
603
604 static int pingpong_cmp(struct alloc_stat *l, struct alloc_stat *r)
605 {
606         if (l->pingpong < r->pingpong)
607                 return -1;
608         else if (l->pingpong > r->pingpong)
609                 return 1;
610         return 0;
611 }
612
613 static struct sort_dimension pingpong_sort_dimension = {
614         .name   = "pingpong",
615         .cmp    = pingpong_cmp,
616 };
617
618 static struct sort_dimension *avail_sorts[] = {
619         &ptr_sort_dimension,
620         &callsite_sort_dimension,
621         &hit_sort_dimension,
622         &bytes_sort_dimension,
623         &frag_sort_dimension,
624         &pingpong_sort_dimension,
625 };
626
627 #define NUM_AVAIL_SORTS \
628         (int)(sizeof(avail_sorts) / sizeof(struct sort_dimension *))
629
630 static int sort_dimension__add(const char *tok, struct list_head *list)
631 {
632         struct sort_dimension *sort;
633         int i;
634
635         for (i = 0; i < NUM_AVAIL_SORTS; i++) {
636                 if (!strcmp(avail_sorts[i]->name, tok)) {
637                         sort = malloc(sizeof(*sort));
638                         if (!sort)
639                                 die("malloc");
640                         memcpy(sort, avail_sorts[i], sizeof(*sort));
641                         list_add_tail(&sort->list, list);
642                         return 0;
643                 }
644         }
645
646         return -1;
647 }
648
649 static int setup_sorting(struct list_head *sort_list, const char *arg)
650 {
651         char *tok;
652         char *str = strdup(arg);
653
654         if (!str)
655                 die("strdup");
656
657         while (true) {
658                 tok = strsep(&str, ",");
659                 if (!tok)
660                         break;
661                 if (sort_dimension__add(tok, sort_list) < 0) {
662                         error("Unknown --sort key: '%s'", tok);
663                         free(str);
664                         return -1;
665                 }
666         }
667
668         free(str);
669         return 0;
670 }
671
672 static int parse_sort_opt(const struct option *opt __used,
673                           const char *arg, int unset __used)
674 {
675         if (!arg)
676                 return -1;
677
678         if (caller_flag > alloc_flag)
679                 return setup_sorting(&caller_sort, arg);
680         else
681                 return setup_sorting(&alloc_sort, arg);
682
683         return 0;
684 }
685
686 static int parse_caller_opt(const struct option *opt __used,
687                           const char *arg __used, int unset __used)
688 {
689         caller_flag = (alloc_flag + 1);
690         return 0;
691 }
692
693 static int parse_alloc_opt(const struct option *opt __used,
694                           const char *arg __used, int unset __used)
695 {
696         alloc_flag = (caller_flag + 1);
697         return 0;
698 }
699
700 static int parse_line_opt(const struct option *opt __used,
701                           const char *arg, int unset __used)
702 {
703         int lines;
704
705         if (!arg)
706                 return -1;
707
708         lines = strtoul(arg, NULL, 10);
709
710         if (caller_flag > alloc_flag)
711                 caller_lines = lines;
712         else
713                 alloc_lines = lines;
714
715         return 0;
716 }
717
718 static const struct option kmem_options[] = {
719         OPT_STRING('i', "input", &input_name, "file",
720                    "input file name"),
721         OPT_CALLBACK_NOOPT(0, "caller", NULL, NULL,
722                            "show per-callsite statistics",
723                            parse_caller_opt),
724         OPT_CALLBACK_NOOPT(0, "alloc", NULL, NULL,
725                            "show per-allocation statistics",
726                            parse_alloc_opt),
727         OPT_CALLBACK('s', "sort", NULL, "key[,key2...]",
728                      "sort by keys: ptr, call_site, bytes, hit, pingpong, frag",
729                      parse_sort_opt),
730         OPT_CALLBACK('l', "line", NULL, "num",
731                      "show n lines",
732                      parse_line_opt),
733         OPT_BOOLEAN(0, "raw-ip", &raw_ip, "show raw ip instead of symbol"),
734         OPT_END()
735 };
736
737 static const char *record_args[] = {
738         "record",
739         "-a",
740         "-R",
741         "-f",
742         "-c", "1",
743         "-e", "kmem:kmalloc",
744         "-e", "kmem:kmalloc_node",
745         "-e", "kmem:kfree",
746         "-e", "kmem:kmem_cache_alloc",
747         "-e", "kmem:kmem_cache_alloc_node",
748         "-e", "kmem:kmem_cache_free",
749 };
750
751 static int __cmd_record(int argc, const char **argv)
752 {
753         unsigned int rec_argc, i, j;
754         const char **rec_argv;
755
756         rec_argc = ARRAY_SIZE(record_args) + argc - 1;
757         rec_argv = calloc(rec_argc + 1, sizeof(char *));
758
759         if (rec_argv == NULL)
760                 return -ENOMEM;
761
762         for (i = 0; i < ARRAY_SIZE(record_args); i++)
763                 rec_argv[i] = strdup(record_args[i]);
764
765         for (j = 1; j < (unsigned int)argc; j++, i++)
766                 rec_argv[i] = argv[j];
767
768         return cmd_record(i, rec_argv, NULL);
769 }
770
771 int cmd_kmem(int argc, const char **argv, const char *prefix __used)
772 {
773         argc = parse_options(argc, argv, kmem_options, kmem_usage, 0);
774
775         if (!argc)
776                 usage_with_options(kmem_usage, kmem_options);
777
778         symbol__init();
779
780         if (!strncmp(argv[0], "rec", 3)) {
781                 return __cmd_record(argc, argv);
782         } else if (!strcmp(argv[0], "stat")) {
783                 setup_cpunode_map();
784
785                 if (list_empty(&caller_sort))
786                         setup_sorting(&caller_sort, default_sort_order);
787                 if (list_empty(&alloc_sort))
788                         setup_sorting(&alloc_sort, default_sort_order);
789
790                 return __cmd_kmem();
791         } else
792                 usage_with_options(kmem_usage, kmem_options);
793
794         return 0;
795 }
796