tools/perf/builtin-diff.c

   1 /*
   2  * builtin-diff.c
   3  *
   4  * Builtin diff command: Analyze two perf.data input files, look up and read
   5  * DSOs and symbol information, sort them and produce a diff.
   6  */
   7 #include "builtin.h"
   8
   9 #include "util/debug.h"
  10 #include "util/event.h"
  11 #include "util/hist.h"
  12 #include "util/session.h"
  13 #include "util/sort.h"
  14 #include "util/symbol.h"
  15 #include "util/util.h"
  16
  17 #include <stdlib.h>
  18
  19 static char const *input_old = "perf.data.old",
  20                   *input_new = "perf.data";
  21 static char       diff__default_sort_order[] = "dso,symbol";
  22 static bool  force;
  23 static bool show_displacement;
  24
  25 static int hists__add_entry(struct hists *self,
  26                             struct addr_location *al, u64 period)
  27 {
  28         if (__hists__add_entry(self, al, NULL, period) != NULL)
  29                 return 0;
  30         return -ENOMEM;
  31 }
  32
  33 static int diff__process_sample_event(event_t *event,
  34                                       struct sample_data *sample,
  35                                       struct perf_session *session)
  36 {
  37         struct addr_location al;
  38
  39         if (event__preprocess_sample(event, session, &al, sample, NULL) < 0) {
  40                 pr_warning("problem processing %d event, skipping it.\n",
  41                            event->header.type);
  42                 return -1;
  43         }
  44
  45         if (al.filtered || al.sym == NULL)
  46                 return 0;
  47
  48         if (hists__add_entry(&session->hists, &al, sample->period)) {
  49                 pr_warning("problem incrementing symbol period, skipping event\n");
  50                 return -1;
  51         }
  52
  53         session->hists.stats.total_period += sample->period;
  54         return 0;
  55 }
  56
  57 static struct perf_event_ops event_ops = {
  58         .sample = diff__process_sample_event,
  59         .mmap   = event__process_mmap,
  60         .comm   = event__process_comm,
  61         .exit   = event__process_task,
  62         .fork   = event__process_task,
  63         .lost   = event__process_lost,
  64 };
  65
  66 static void perf_session__insert_hist_entry_by_name(struct rb_root *root,
  67                                                     struct hist_entry *he)
  68 {
  69         struct rb_node **p = &root->rb_node;
  70         struct rb_node *parent = NULL;
  71         struct hist_entry *iter;
  72
  73         while (*p != NULL) {
  74                 parent = *p;
  75                 iter = rb_entry(parent, struct hist_entry, rb_node);
  76                 if (hist_entry__cmp(he, iter) < 0)
  77                         p = &(*p)->rb_left;
  78                 else
  79                         p = &(*p)->rb_right;
  80         }
  81
  82         rb_link_node(&he->rb_node, parent, p);
  83         rb_insert_color(&he->rb_node, root);
  84 }
  85
  86 static void hists__resort_entries(struct hists *self)
  87 {
  88         unsigned long position = 1;
  89         struct rb_root tmp = RB_ROOT;
  90         struct rb_node *next = rb_first(&self->entries);
  91
  92         while (next != NULL) {
  93                 struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
  94
  95                 next = rb_next(&n->rb_node);
  96                 rb_erase(&n->rb_node, &self->entries);
  97                 n->position = position++;
  98                 perf_session__insert_hist_entry_by_name(&tmp, n);
  99         }
 100
 101         self->entries = tmp;
 102 }
 103
 104 static void hists__set_positions(struct hists *self)
 105 {
 106         hists__output_resort(self);
 107         hists__resort_entries(self);
 108 }
 109
 110 static struct hist_entry *hists__find_entry(struct hists *self,
 111                                             struct hist_entry *he)
 112 {
 113         struct rb_node *n = self->entries.rb_node;
 114
 115         while (n) {
 116                 struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
 117                 int64_t cmp = hist_entry__cmp(he, iter);
 118
 119                 if (cmp < 0)
 120                         n = n->rb_left;
 121                 else if (cmp > 0)
 122                         n = n->rb_right;
 123                 else
 124                         return iter;
 125         }
 126
 127         return NULL;
 128 }
 129
 130 static void hists__match(struct hists *older, struct hists *newer)
 131 {
 132         struct rb_node *nd;
 133
 134         for (nd = rb_first(&newer->entries); nd; nd = rb_next(nd)) {
 135                 struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
 136                 pos->pair = hists__find_entry(older, pos);
 137         }
 138 }
 139
 140 static int __cmd_diff(void)
 141 {
 142         int ret, i;
 143         struct perf_session *session[2];
 144
 145         session[0] = perf_session__new(input_old, O_RDONLY, force, false);
 146         session[1] = perf_session__new(input_new, O_RDONLY, force, false);
 147         if (session[0] == NULL || session[1] == NULL)
 148                 return -ENOMEM;
 149
 150         for (i = 0; i < 2; ++i) {
 151                 ret = perf_session__process_events(session[i], &event_ops);
 152                 if (ret)
 153                         goto out_delete;
 154         }
 155
 156         hists__output_resort(&session[1]->hists);
 157         if (show_displacement)
 158                 hists__set_positions(&session[0]->hists);
 159
 160         hists__match(&session[0]->hists, &session[1]->hists);
 161         hists__fprintf(&session[1]->hists, &session[0]->hists,
 162                        show_displacement, stdout);
 163 out_delete:
 164         for (i = 0; i < 2; ++i)
 165                 perf_session__delete(session[i]);
 166         return ret;
 167 }
 168
 169 static const char * const diff_usage[] = {
 170         "perf diff [<options>] [old_file] [new_file]",
 171         NULL,
 172 };
 173
 174 static const struct option options[] = {
 175         OPT_INCR('v', "verbose", &verbose,
 176                     "be more verbose (show symbol address, etc)"),
 177         OPT_BOOLEAN('M', "displacement", &show_displacement,
 178                     "Show position displacement relative to baseline"),
 179         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 180                     "dump raw trace in ASCII"),
 181         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 182         OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 183                     "load module symbols - WARNING: use only with -k and LIVE kernel"),
 184         OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 185                    "only consider symbols in these dsos"),
 186         OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 187                    "only consider symbols in these comms"),
 188         OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 189                    "only consider these symbols"),
 190         OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 191                    "sort by key(s): pid, comm, dso, symbol, parent"),
 192         OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 193                    "separator for columns, no spaces will be added between "
 194                    "columns '.' is reserved."),
 195         OPT_END()
 196 };
 197
 198 int cmd_diff(int argc, const char **argv, const char *prefix __used)
 199 {
 200         sort_order = diff__default_sort_order;
 201         argc = parse_options(argc, argv, options, diff_usage, 0);
 202         if (argc) {
 203                 if (argc > 2)
 204                         usage_with_options(diff_usage, options);
 205                 if (argc == 2) {
 206                         input_old = argv[0];
 207                         input_new = argv[1];
 208                 } else
 209                         input_new = argv[0];
 210         } else if (symbol_conf.default_guest_vmlinux_name ||
 211                    symbol_conf.default_guest_kallsyms) {
 212                 input_old = "perf.data.host";
 213                 input_new = "perf.data.guest";
 214         }
 215
 216         symbol_conf.exclude_other = false;
 217         if (symbol__init() < 0)
 218                 return -1;
 219
 220         setup_sorting(diff_usage, options);
 221         setup_pager();
 222
 223         sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
 224         sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
 225         sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
 226
 227         return __cmd_diff();
 228 }