perf tools: Refactor code to move call path handling out of thread-stack

Move the call path handling code out of thread-stack.c and
thread-stack.h to allow other components that are not part of
thread-stack to create call paths.

Summary:

- Create call-path.c and call-path.h and add them to the build.

- Move all call path related code out of thread-stack.c and thread-stack.h
  and into call-path.c and call-path.h.

- A small subset of structures and functions are now visible through
  call-path.h, which is required for thread-stack.c to continue to
  compile.

This change is a prerequisite for subsequent patches in this change set
and by itself contains no user-visible changes.

Signed-off-by: Chris Phlipot <cphlipot0@gmail.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461831551-12213-3-git-send-email-cphlipot0@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 122 insertions, 0 deletions

diff --git a/tools/perf/util/call-path.c b/tools/perf/util/call-path.c
new file mode 100644
index 000000000000..904a17052e38
--- /dev/null
+++ b/tools/perf/util/call-path.c
@@ -0,0 +1,122 @@
+/*
+ * call-path.h: Manipulate a tree data structure containing function call paths
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#include <linux/rbtree.h>
+#include <linux/list.h>
+
+#include "util.h"
+#include "call-path.h"
+
+static void call_path__init(struct call_path *cp, struct call_path *parent,
+                            struct symbol *sym, u64 ip, bool in_kernel)
+{
+        cp->parent = parent;
+        cp->sym = sym;
+        cp->ip = sym ? 0 : ip;
+        cp->db_id = 0;
+        cp->in_kernel = in_kernel;
+        RB_CLEAR_NODE(&cp->rb_node);
+        cp->children = RB_ROOT;
+}
+
+struct call_path_root *call_path_root__new(void)
+{
+        struct call_path_root *cpr;
+
+        cpr = zalloc(sizeof(struct call_path_root));
+        if (!cpr)
+                return NULL;
+        call_path__init(&cpr->call_path, NULL, NULL, 0, false);
+        INIT_LIST_HEAD(&cpr->blocks);
+        return cpr;
+}
+
+void call_path_root__free(struct call_path_root *cpr)
+{
+        struct call_path_block *pos, *n;
+
+        list_for_each_entry_safe(pos, n, &cpr->blocks, node) {
+                list_del(&pos->node);
+                free(pos);
+        }
+        free(cpr);
+}
+
+static struct call_path *call_path__new(struct call_path_root *cpr,
+                                        struct call_path *parent,
+                                        struct symbol *sym, u64 ip,
+                                        bool in_kernel)
+{
+        struct call_path_block *cpb;
+        struct call_path *cp;
+        size_t n;
+
+        if (cpr->next < cpr->sz) {
+                cpb = list_last_entry(&cpr->blocks, struct call_path_block,
+                                      node);
+        } else {
+                cpb = zalloc(sizeof(struct call_path_block));
+                if (!cpb)
+                        return NULL;
+                list_add_tail(&cpb->node, &cpr->blocks);
+                cpr->sz += CALL_PATH_BLOCK_SIZE;
+        }
+
+        n = cpr->next++ & CALL_PATH_BLOCK_MASK;
+        cp = &cpb->cp[n];
+
+        call_path__init(cp, parent, sym, ip, in_kernel);
+
+        return cp;
+}
+
+struct call_path *call_path__findnew(struct call_path_root *cpr,
+                                     struct call_path *parent,
+                                     struct symbol *sym, u64 ip, u64 ks)
+{
+        struct rb_node **p;
+        struct rb_node *node_parent = NULL;
+        struct call_path *cp;
+        bool in_kernel = ip >= ks;
+
+        if (sym)
+                ip = 0;
+
+        if (!parent)
+                return call_path__new(cpr, parent, sym, ip, in_kernel);
+
+        p = &parent->children.rb_node;
+        while (*p != NULL) {
+                node_parent = *p;
+                cp = rb_entry(node_parent, struct call_path, rb_node);
+
+                if (cp->sym == sym && cp->ip == ip)
+                        return cp;
+
+                if (sym < cp->sym || (sym == cp->sym && ip < cp->ip))
+                        p = &(*p)->rb_left;
+                else
+                        p = &(*p)->rb_right;
+        }
+
+        cp = call_path__new(cpr, parent, sym, ip, in_kernel);
+        if (!cp)
+                return NULL;
+
+        rb_link_node(&cp->rb_node, node_parent, p);
+        rb_insert_color(&cp->rb_node, &parent->children);
+
+        return cp;
+}