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