1 files changed, 249 insertions, 0 deletions

diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
new file mode 100644
index 000000000000..bd71b8ceafb7
--- /dev/null
+++ b/tools/perf/builtin-diff.c
@@ -0,0 +1,249 @@
+/*
+ * builtin-diff.c
+ *
+ * Builtin diff command: Analyze two perf.data input files, look up and read
+ * DSOs and symbol information, sort them and produce a diff.
+ */
+#include "builtin.h"
+
+#include "util/debug.h"
+#include "util/event.h"
+#include "util/hist.h"
+#include "util/session.h"
+#include "util/sort.h"
+#include "util/symbol.h"
+#include "util/util.h"
+
+#include <stdlib.h>
+
+static char const *input_old = "perf.data.old",
+                  *input_new = "perf.data";
+static char       diff__default_sort_order[] = "dso,symbol";
+static int  force;
+static bool show_displacement;
+
+static int perf_session__add_hist_entry(struct perf_session *self,
+                                        struct addr_location *al, u64 count)
+{
+        bool hit;
+        struct hist_entry *he = __perf_session__add_hist_entry(self, al, NULL,
+                                                               count, &hit);
+        if (he == NULL)
+                return -ENOMEM;
+
+        if (hit)
+                he->count += count;
+
+        return 0;
+}
+
+static int diff__process_sample_event(event_t *event, struct perf_session *session)
+{
+        struct addr_location al;
+        struct sample_data data = { .period = 1, };
+
+        dump_printf("(IP, %d): %d: %p\n", event->header.misc,
+                    event->ip.pid, (void *)(long)event->ip.ip);
+
+        if (event__preprocess_sample(event, session, &al, NULL) < 0) {
+                pr_warning("problem processing %d event, skipping it.\n",
+                           event->header.type);
+                return -1;
+        }
+
+        if (al.filtered)
+                return 0;
+
+        event__parse_sample(event, session->sample_type, &data);
+
+        if (al.sym && perf_session__add_hist_entry(session, &al, data.period)) {
+                pr_warning("problem incrementing symbol count, skipping event\n");
+                return -1;
+        }
+
+        session->events_stats.total += data.period;
+        return 0;
+}
+
+static struct perf_event_ops event_ops = {
+        .process_sample_event = diff__process_sample_event,
+        .process_mmap_event   = event__process_mmap,
+        .process_comm_event   = event__process_comm,
+        .process_exit_event   = event__process_task,
+        .process_fork_event   = event__process_task,
+        .process_lost_event   = event__process_lost,
+};
+
+static void perf_session__insert_hist_entry_by_name(struct rb_root *root,
+                                                    struct hist_entry *he)
+{
+        struct rb_node **p = &root->rb_node;
+        struct rb_node *parent = NULL;
+        struct hist_entry *iter;
+
+        while (*p != NULL) {
+                int cmp;
+                parent = *p;
+                iter = rb_entry(parent, struct hist_entry, rb_node);
+
+                cmp = strcmp(he->map->dso->name, iter->map->dso->name);
+                if (cmp > 0)
+                        p = &(*p)->rb_left;
+                else if (cmp < 0)
+                        p = &(*p)->rb_right;
+                else {
+                        cmp = strcmp(he->sym->name, iter->sym->name);
+                        if (cmp > 0)
+                                p = &(*p)->rb_left;
+                        else
+                                p = &(*p)->rb_right;
+                }
+        }
+
+        rb_link_node(&he->rb_node, parent, p);
+        rb_insert_color(&he->rb_node, root);
+}
+
+static void perf_session__resort_by_name(struct perf_session *self)
+{
+        unsigned long position = 1;
+        struct rb_root tmp = RB_ROOT;
+        struct rb_node *next = rb_first(&self->hists);
+
+        while (next != NULL) {
+                struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
+
+                next = rb_next(&n->rb_node);
+                rb_erase(&n->rb_node, &self->hists);
+                n->position = position++;
+                perf_session__insert_hist_entry_by_name(&tmp, n);
+        }
+
+        self->hists = tmp;
+}
+
+static struct hist_entry *
+perf_session__find_hist_entry_by_name(struct perf_session *self,
+                                      struct hist_entry *he)
+{
+        struct rb_node *n = self->hists.rb_node;
+
+        while (n) {
+                struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
+                int cmp = strcmp(he->map->dso->name, iter->map->dso->name);
+
+                if (cmp > 0)
+                        n = n->rb_left;
+                else if (cmp < 0)
+                        n = n->rb_right;
+                else {
+                        cmp = strcmp(he->sym->name, iter->sym->name);
+                        if (cmp > 0)
+                                n = n->rb_left;
+                        else if (cmp < 0)
+                                n = n->rb_right;
+                        else
+                                return iter;
+                }
+        }
+
+        return NULL;
+}
+
+static void perf_session__match_hists(struct perf_session *old_session,
+                                      struct perf_session *new_session)
+{
+        struct rb_node *nd;
+
+        perf_session__resort_by_name(old_session);
+
+        for (nd = rb_first(&new_session->hists); nd; nd = rb_next(nd)) {
+                struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
+                pos->pair = perf_session__find_hist_entry_by_name(old_session, pos);
+        }
+}
+
+static int __cmd_diff(void)
+{
+        int ret, i;
+        struct perf_session *session[2];
+
+        session[0] = perf_session__new(input_old, O_RDONLY, force);
+        session[1] = perf_session__new(input_new, O_RDONLY, force);
+        if (session[0] == NULL || session[1] == NULL)
+                return -ENOMEM;
+
+        for (i = 0; i < 2; ++i) {
+                ret = perf_session__process_events(session[i], &event_ops);
+                if (ret)
+                        goto out_delete;
+                perf_session__output_resort(session[i], session[i]->events_stats.total);
+        }
+
+        perf_session__match_hists(session[0], session[1]);
+        perf_session__fprintf_hists(session[1], session[0],
+                                    show_displacement, stdout);
+out_delete:
+        for (i = 0; i < 2; ++i)
+                perf_session__delete(session[i]);
+        return ret;
+}
+
+static const char * const diff_usage[] = {
+        "perf diff [<options>] [old_file] [new_file]",
+        NULL,
+};
+
+static const struct option options[] = {
+        OPT_BOOLEAN('v', "verbose", &verbose,
+                    "be more verbose (show symbol address, etc)"),
+        OPT_BOOLEAN('m', "displacement", &show_displacement,
+                    "Show position displacement relative to baseline"),
+        OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
+                    "dump raw trace in ASCII"),
+        OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
+        OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
+                    "load module symbols - WARNING: use only with -k and LIVE kernel"),
+        OPT_BOOLEAN('P', "full-paths", &event_ops.full_paths,
+                    "Don't shorten the pathnames taking into account the cwd"),
+        OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
+                   "only consider symbols in these dsos"),
+        OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
+                   "only consider symbols in these comms"),
+        OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
+                   "only consider these symbols"),
+        OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
+                   "sort by key(s): pid, comm, dso, symbol, parent"),
+        OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
+                   "separator for columns, no spaces will be added between "
+                   "columns '.' is reserved."),
+        OPT_END()
+};
+
+int cmd_diff(int argc, const char **argv, const char *prefix __used)
+{
+        sort_order = diff__default_sort_order;
+        argc = parse_options(argc, argv, options, diff_usage, 0);
+        if (argc) {
+                if (argc > 2)
+                        usage_with_options(diff_usage, options);
+                if (argc == 2) {
+                        input_old = argv[0];
+                        input_new = argv[1];
+                } else
+                        input_new = argv[0];
+        }
+
+        symbol_conf.exclude_other = false;
+        if (symbol__init() < 0)
+                return -1;
+
+        setup_sorting(diff_usage, options);
+        setup_pager();
+
+        sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
+        sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
+        sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
+
+        return __cmd_diff();
+}