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(union perf_event *event,
  34                                       struct perf_sample *sample,
  35                                       struct perf_evsel *evsel __used,
  36                                       struct perf_session *session)
  37 {
  38         struct addr_location al;
  39
  40         if (perf_event__preprocess_sample(event, session, &al, sample, NULL) < 0) {
  41                 pr_warning("problem processing %d event, skipping it.\n",
  42                            event->header.type);
  43                 return -1;
  44         }
  45
  46         if (al.filtered || al.sym == NULL)
  47                 return 0;
  48
  49         if (hists__add_entry(&session->hists, &al, sample->period)) {
  50                 pr_warning("problem incrementing symbol period, skipping event\n");
  51                 return -1;
  52         }
  53
  54         session->hists.stats.total_period += sample->period;
  55         return 0;
  56 }
  57
  58 static struct perf_event_ops event_ops = {
  59         .sample = diff__process_sample_event,
  60         .mmap   = perf_event__process_mmap,
  61         .comm   = perf_event__process_comm,
  62         .exit   = perf_event__process_task,
  63         .fork   = perf_event__process_task,
  64         .lost   = perf_event__process_lost,
  65         .ordered_samples = true,
  66         .ordering_requires_timestamps = true,
  67 };
  68
  69 static void perf_session__insert_hist_entry_by_name(struct rb_root *root,
  70                                                     struct hist_entry *he)
  71 {
  72         struct rb_node **p = &root->rb_node;
  73         struct rb_node *parent = NULL;
  74         struct hist_entry *iter;
  75
  76         while (*p != NULL) {
  77                 parent = *p;
  78                 iter = rb_entry(parent, struct hist_entry, rb_node);
  79                 if (hist_entry__cmp(he, iter) < 0)
  80                         p = &(*p)->rb_left;
  81                 else
  82                         p = &(*p)->rb_right;
  83         }
  84
  85         rb_link_node(&he->rb_node, parent, p);
  86         rb_insert_color(&he->rb_node, root);
  87 }
  88
  89 static void hists__resort_entries(struct hists *self)
  90 {
  91         unsigned long position = 1;
  92         struct rb_root tmp = RB_ROOT;
  93         struct rb_node *next = rb_first(&self->entries);
  94
  95         while (next != NULL) {
  96                 struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
  97
  98                 next = rb_next(&n->rb_node);
  99                 rb_erase(&n->rb_node, &self->entries);
 100                 n->position = position++;
 101                 perf_session__insert_hist_entry_by_name(&tmp, n);
 102         }
 103
 104         self->entries = tmp;
 105 }
 106
 107 static void hists__set_positions(struct hists *self)
 108 {
 109         hists__output_resort(self);
 110         hists__resort_entries(self);
 111 }
 112
 113 static struct hist_entry *hists__find_entry(struct hists *self,
 114                                             struct hist_entry *he)
 115 {
 116         struct rb_node *n = self->entries.rb_node;
 117
 118         while (n) {
 119                 struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
 120                 int64_t cmp = hist_entry__cmp(he, iter);
 121
 122                 if (cmp < 0)
 123                         n = n->rb_left;
 124                 else if (cmp > 0)
 125                         n = n->rb_right;
 126                 else
 127                         return iter;
 128         }
 129
 130         return NULL;
 131 }
 132
 133 static void hists__match(struct hists *older, struct hists *newer)
 134 {
 135         struct rb_node *nd;
 136
 137         for (nd = rb_first(&newer->entries); nd; nd = rb_next(nd)) {
 138                 struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
 139                 pos->pair = hists__find_entry(older, pos);
 140         }
 141 }
 142
 143 static int __cmd_diff(void)
 144 {
 145         int ret, i;
 146         struct perf_session *session[2];
 147
 148         session[0] = perf_session__new(input_old, O_RDONLY, force, false, &event_ops);
 149         session[1] = perf_session__new(input_new, O_RDONLY, force, false, &event_ops);
 150         if (session[0] == NULL || session[1] == NULL)
 151                 return -ENOMEM;
 152
 153         for (i = 0; i < 2; ++i) {
 154                 ret = perf_session__process_events(session[i], &event_ops);
 155                 if (ret)
 156                         goto out_delete;
 157         }
 158
 159         hists__output_resort(&session[1]->hists);
 160         if (show_displacement)
 161                 hists__set_positions(&session[0]->hists);
 162
 163         hists__match(&session[0]->hists, &session[1]->hists);
 164         hists__fprintf(&session[1]->hists, &session[0]->hists,
 165                        show_displacement, stdout);
 166 out_delete:
 167         for (i = 0; i < 2; ++i)
 168                 perf_session__delete(session[i]);
 169         return ret;
 170 }
 171
 172 static const char * const diff_usage[] = {
 173         "perf diff [<options>] [old_file] [new_file]",
 174         NULL,
 175 };
 176
 177 static const struct option options[] = {
 178         OPT_INCR('v', "verbose", &verbose,
 179                     "be more verbose (show symbol address, etc)"),
 180         OPT_BOOLEAN('M', "displacement", &show_displacement,
 181                     "Show position displacement relative to baseline"),
 182         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 183                     "dump raw trace in ASCII"),
 184         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 185         OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 186                     "load module symbols - WARNING: use only with -k and LIVE kernel"),
 187         OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 188                    "only consider symbols in these dsos"),
 189         OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 190                    "only consider symbols in these comms"),
 191         OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 192                    "only consider these symbols"),
 193         OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 194                    "sort by key(s): pid, comm, dso, symbol, parent"),
 195         OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 196                    "separator for columns, no spaces will be added between "
 197                    "columns '.' is reserved."),
 198         OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 199                     "Look for files with symbols relative to this directory"),
 200         OPT_END()
 201 };
 202
 203 int cmd_diff(int argc, const char **argv, const char *prefix __used)
 204 {
 205         sort_order = diff__default_sort_order;
 206         argc = parse_options(argc, argv, options, diff_usage, 0);
 207         if (argc) {
 208                 if (argc > 2)
 209                         usage_with_options(diff_usage, options);
 210                 if (argc == 2) {
 211                         input_old = argv[0];
 212                         input_new = argv[1];
 213                 } else
 214                         input_new = argv[0];
 215         } else if (symbol_conf.default_guest_vmlinux_name ||
 216                    symbol_conf.default_guest_kallsyms) {
 217                 input_old = "perf.data.host";
 218                 input_new = "perf.data.guest";
 219         }
 220
 221         symbol_conf.exclude_other = false;
 222         if (symbol__init() < 0)
 223                 return -1;
 224
 225         setup_sorting(diff_usage, options);
 226         setup_pager();
 227
 228         sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
 229         sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
 230         sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
 231
 232         return __cmd_diff();
 233 }