perf report: Add support for callchain graph output

Currently, the printing of callchains is done in a single
vertical level, this is the "flat" mode:

8.25%  [k] copy_user_generic_string
             4.19%
                copy_user_generic_string
                generic_file_aio_read
                do_sync_read
                vfs_read
                sys_pread64
                system_call_fastpath
                pread64

This patch introduces a new "graph" mode which provides a
hierarchical output of factorized paths recursively sorted:

 8.25%  [k] copy_user_generic_string
                |
                |--4.31%-- generic_file_aio_read
                |          do_sync_read
                |          vfs_read
                |          |
                |          |--4.19%-- sys_pread64
                |          |          system_call_fastpath
                |          |          pread64
                |          |
                |           --0.12%-- sys_read
                |                     system_call_fastpath
                |                     __read
                |
                |--3.24%-- generic_file_buffered_write
                |          __generic_file_aio_write_nolock
                |          generic_file_aio_write
                |          do_sync_write
                |          reiserfs_file_write
                |          vfs_write
                |          |
                |          |--3.14%-- sys_pwrite64
                |          |          system_call_fastpath
                |          |          __pwrite64
                |          |
                |           --0.10%-- sys_write
[...]

The command line has then changed.

By providing the -c option, the callchain will output in the
flat mode by default.

But you can override it:

    perf report -c graph

or

    perf report -c flat

You can also pass the abreviated mode:

    perf report -c g

or

    perf report -c gra

will both make use of the graph mode.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246550301-8954-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index b44476c..0ca4638 100644 (file)
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -59,6 +59,7 @@ static regex_t                parent_regex;
 
 static int             exclude_other = 1;
 static int             callchain;
+static enum chain_mode callchain_mode;
 
 static u64             sample_type;
 
@@ -787,8 +788,103 @@ hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
        return cmp;
 }
 
+static size_t ipchain__fprintf_graph_line(FILE *fp, int depth, int depth_mask)
+{
+       int i;
+       size_t ret = 0;
+
+       ret += fprintf(fp, "%s", "                ");
+
+       for (i = 0; i < depth; i++)
+               if (depth_mask & (1 << i))
+                       ret += fprintf(fp, "|          ");
+               else
+                       ret += fprintf(fp, "           ");
+
+       ret += fprintf(fp, "\n");
+
+       return ret;
+}
 static size_t
-callchain__fprintf(FILE *fp, struct callchain_node *self, u64 total_samples)
+ipchain__fprintf_graph(FILE *fp, struct callchain_list *chain, int depth,
+                      int depth_mask, int count, u64 total_samples,
+                      int hits)
+{
+       int i;
+       size_t ret = 0;
+
+       ret += fprintf(fp, "%s", "                ");
+       for (i = 0; i < depth; i++) {
+               if (depth_mask & (1 << i))
+                       ret += fprintf(fp, "|");
+               else
+                       ret += fprintf(fp, " ");
+               if (!count && i == depth - 1) {
+                       double percent;
+
+                       percent = hits * 100.0 / total_samples;
+                       ret += fprintf(fp, "--%2.2f%%-- ", percent);
+               } else
+                       ret += fprintf(fp, "%s", "          ");
+       }
+       if (chain->sym)
+               ret += fprintf(fp, "%s\n", chain->sym->name);
+       else
+               ret += fprintf(fp, "%p\n", (void *)(long)chain->ip);
+
+       return ret;
+}
+
+static size_t
+callchain__fprintf_graph(FILE *fp, struct callchain_node *self,
+                       u64 total_samples, int depth, int depth_mask)
+{
+       struct rb_node *node, *next;
+       struct callchain_node *child;
+       struct callchain_list *chain;
+       int new_depth_mask = depth_mask;
+       size_t ret = 0;
+       int i;
+
+       node = rb_first(&self->rb_root);
+       while (node) {
+               child = rb_entry(node, struct callchain_node, rb_node);
+
+               /*
+                * The depth mask manages the output of pipes that show
+                * the depth. We don't want to keep the pipes of the current
+                * level for the last child of this depth
+                */
+               next = rb_next(node);
+               if (!next)
+                       new_depth_mask &= ~(1 << (depth - 1));
+
+               /*
+                * But we keep the older depth mask for the line seperator
+                * to keep the level link until we reach the last child
+                */
+               ret += ipchain__fprintf_graph_line(fp, depth, depth_mask);
+               i = 0;
+               list_for_each_entry(chain, &child->val, list) {
+                       if (chain->ip >= PERF_CONTEXT_MAX)
+                               continue;
+                       ret += ipchain__fprintf_graph(fp, chain, depth,
+                                                     new_depth_mask, i++,
+                                                     total_samples,
+                                                     child->cumul_hit);
+               }
+               ret += callchain__fprintf_graph(fp, child, total_samples,
+                                               depth + 1,
+                                               new_depth_mask | (1 << depth));
+               node = next;
+       }
+
+       return ret;
+}
+
+static size_t
+callchain__fprintf_flat(FILE *fp, struct callchain_node *self,
+                       u64 total_samples)
 {
        struct callchain_list *chain;
        size_t ret = 0;
@@ -796,7 +892,7 @@ callchain__fprintf(FILE *fp, struct callchain_node *self, u64 total_samples)
        if (!self)
                return 0;
 
-       ret += callchain__fprintf(fp, self->parent, total_samples);
+       ret += callchain__fprintf_flat(fp, self->parent, total_samples);
 
 
        list_for_each_entry(chain, &self->val, list) {
@@ -826,8 +922,13 @@ hist_entry_callchain__fprintf(FILE *fp, struct hist_entry *self,
 
                chain = rb_entry(rb_node, struct callchain_node, rb_node);
                percent = chain->hit * 100.0 / total_samples;
-               ret += fprintf(fp, "           %6.2f%%\n", percent);
-               ret += callchain__fprintf(fp, chain, total_samples);
+               if (callchain_mode == FLAT) {
+                       ret += fprintf(fp, "           %6.2f%%\n", percent);
+                       ret += callchain__fprintf_flat(fp, chain, total_samples);
+               } else if (callchain_mode == GRAPH) {
+                       ret += callchain__fprintf_graph(fp, chain,
+                                                       total_samples, 1, 1);
+               }
                ret += fprintf(fp, "\n");
                rb_node = rb_next(rb_node);
        }
@@ -1129,8 +1230,12 @@ static void output__insert_entry(struct hist_entry *he)
        struct rb_node *parent = NULL;
        struct hist_entry *iter;
 
-       if (callchain)
-               sort_chain_to_rbtree(&he->sorted_chain, &he->callchain);
+       if (callchain) {
+               if (callchain_mode == FLAT)
+                       sort_chain_flat(&he->sorted_chain, &he->callchain);
+               else if (callchain_mode == GRAPH)
+                       sort_chain_graph(&he->sorted_chain, &he->callchain);
+       }
 
        while (*p != NULL) {
                parent = *p;
@@ -1702,6 +1807,26 @@ done:
        return rc;
 }
 
+static int
+parse_callchain_opt(const struct option *opt __used, const char *arg,
+                   int unset __used)
+{
+       callchain = 1;
+
+       if (!arg)
+               return 0;
+
+       if (!strncmp(arg, "graph", strlen(arg)))
+               callchain_mode = GRAPH;
+
+       else if (!strncmp(arg, "flat", strlen(arg)))
+               callchain_mode = FLAT;
+       else
+               return -1;
+
+       return 0;
+}
+
 static const char * const report_usage[] = {
        "perf report [<options>] <command>",
        NULL
@@ -1725,7 +1850,9 @@ static const struct option options[] = {
                   "regex filter to identify parent, see: '--sort parent'"),
        OPT_BOOLEAN('x', "exclude-other", &exclude_other,
                    "Only display entries with parent-match"),
-       OPT_BOOLEAN('c', "callchain", &callchain, "Display callchains"),
+       OPT_CALLBACK_DEFAULT('c', "callchain", NULL, "output_type",
+                    "Display callchains with output_type: flat, graph. "
+                    "Default to flat", &parse_callchain_opt, "flat"),
        OPT_STRING('d', "dsos", &dso_list_str, "dso[,dso...]",
                   "only consider symbols in these dsos"),
        OPT_STRING('C', "comms", &comm_list_str, "comm[,comm...]",

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 3c4a91f..a9873aa 100644 (file)
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -19,9 +19,9 @@
 #define chain_for_each_child(child, parent)    \
        list_for_each_entry(child, &parent->children, brothers)
 
-
 static void
-rb_insert_callchain(struct rb_root *root, struct callchain_node *chain)
+rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
+                   enum chain_mode mode)
 {
        struct rb_node **p = &root->rb_node;
        struct rb_node *parent = NULL;
@@ -31,10 +31,22 @@ rb_insert_callchain(struct rb_root *root, struct callchain_node *chain)
                parent = *p;
                rnode = rb_entry(parent, struct callchain_node, rb_node);
 
-               if (rnode->hit < chain->hit)
-                       p = &(*p)->rb_left;
-               else
-                       p = &(*p)->rb_right;
+               switch (mode) {
+               case FLAT:
+                       if (rnode->hit < chain->hit)
+                               p = &(*p)->rb_left;
+                       else
+                               p = &(*p)->rb_right;
+                       break;
+               case GRAPH:
+                       if (rnode->cumul_hit < chain->cumul_hit)
+                               p = &(*p)->rb_left;
+                       else
+                               p = &(*p)->rb_right;
+                       break;
+               default:
+                       break;
+               }
        }
 
        rb_link_node(&chain->rb_node, parent, p);
@@ -45,15 +57,36 @@ rb_insert_callchain(struct rb_root *root, struct callchain_node *chain)
  * Once we get every callchains from the stream, we can now
  * sort them by hit
  */
-void sort_chain_to_rbtree(struct rb_root *rb_root, struct callchain_node *node)
+void sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node)
 {
        struct callchain_node *child;
 
        chain_for_each_child(child, node)
-               sort_chain_to_rbtree(rb_root, child);
+               sort_chain_flat(rb_root, child);
 
        if (node->hit)
-               rb_insert_callchain(rb_root, node);
+               rb_insert_callchain(rb_root, node, FLAT);
+}
+
+static void __sort_chain_graph(struct callchain_node *node)
+{
+       struct callchain_node *child;
+
+       node->rb_root = RB_ROOT;
+       node->cumul_hit = node->hit;
+
+       chain_for_each_child(child, node) {
+               __sort_chain_graph(child);
+               rb_insert_callchain(&node->rb_root, child, GRAPH);
+               node->cumul_hit += child->cumul_hit;
+       }
+}
+
+void
+sort_chain_graph(struct rb_root *rb_root, struct callchain_node *chain_root)
+{
+       __sort_chain_graph(chain_root);
+       rb_root->rb_node = chain_root->rb_root.rb_node;
 }
 
 /*

diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index e9bd5e8..dfa5600 100644 (file)
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -6,15 +6,21 @@
 #include <linux/rbtree.h>
 #include "symbol.h"
 
+enum chain_mode {
+       FLAT,
+       GRAPH
+};
 
 struct callchain_node {
        struct callchain_node   *parent;
        struct list_head        brothers;
        struct list_head        children;
        struct list_head        val;
-       struct rb_node          rb_node;
+       struct rb_node          rb_node; /* to sort nodes in an rbtree */
+       struct rb_root          rb_root; /* sorted tree of children */
        unsigned int            val_nr;
        u64                     hit;
+       u64                     cumul_hit; /* hit + hits of children */
 };
 
 struct callchain_list {
@@ -32,5 +38,6 @@ static inline void callchain_init(struct callchain_node *node)
 
 void append_chain(struct callchain_node *root, struct ip_callchain *chain,
                  struct symbol **syms);
-void sort_chain_to_rbtree(struct rb_root *rb_root, struct callchain_node *node);
+void sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node);
+void sort_chain_graph(struct rb_root *rb_root, struct callchain_node *node);
 #endif