[PATCH 2/6] perf tools: refractor code to move call path handling out of thread-stack

[Chris Phlipot]

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@xxxxxxxxx>
---
 tools/perf/util/Build                              |   1 +
 tools/perf/util/call-path.c                        | 122 ++++++++++++++++++++
 tools/perf/util/call-path.h                        |  77 +++++++++++++
 tools/perf/util/db-export.c                        |   1 +
 .../util/scripting-engines/trace-event-python.c    |   1 +
 tools/perf/util/thread-stack.c                     | 126 +--------------------
 tools/perf/util/thread-stack.h                     |  25 +---
 7 files changed, 204 insertions(+), 149 deletions(-)
 create mode 100644 tools/perf/util/call-path.c
 create mode 100644 tools/perf/util/call-path.h

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index 90229a8..027bb2b 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -74,6 +74,7 @@ libperf-y += srcline.o
 libperf-y += data.o
 libperf-y += tsc.o
 libperf-y += cloexec.o
+libperf-y += call-path.o
 libperf-y += thread-stack.o
 libperf-$(CONFIG_AUXTRACE) += auxtrace.o
 libperf-$(CONFIG_AUXTRACE) += intel-pt-decoder/
diff --git a/tools/perf/util/call-path.c b/tools/perf/util/call-path.c
new file mode 100644
index 0000000..904a170
--- /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;
+}
diff --git a/tools/perf/util/call-path.h b/tools/perf/util/call-path.h
new file mode 100644
index 0000000..477f6d0
--- /dev/null
+++ b/tools/perf/util/call-path.h
@@ -0,0 +1,77 @@
+/*
+ * 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.
+ *
+ */
+
+#ifndef __PERF_CALL_PATH_H
+#define __PERF_CALL_PATH_H
+
+#include <sys/types.h>
+
+#include <linux/types.h>
+#include <linux/rbtree.h>
+
+/**
+ * struct call_path - node in list of calls leading to a function call.
+ * @parent: call path to the parent function call
+ * @sym: symbol of function called
+ * @ip: only if sym is null, the ip of the function
+ * @db_id: id used for db-export
+ * @in_kernel: whether function is a in the kernel
+ * @rb_node: node in parent's tree of called functions
+ * @children: tree of call paths of functions called
+ *
+ * In combination with the call_return structure, the call_path structure
+ * defines a context-sensitve call-graph.
+ */
+struct call_path {
+	struct call_path *parent;
+	struct symbol *sym;
+	u64 ip;
+	u64 db_id;
+	bool in_kernel;
+	struct rb_node rb_node;
+	struct rb_root children;
+};
+
+#define CALL_PATH_BLOCK_SHIFT 8
+#define CALL_PATH_BLOCK_SIZE (1 << CALL_PATH_BLOCK_SHIFT)
+#define CALL_PATH_BLOCK_MASK (CALL_PATH_BLOCK_SIZE - 1)
+
+struct call_path_block {
+	struct call_path cp[CALL_PATH_BLOCK_SIZE];
+	struct list_head node;
+};
+
+/**
+ * struct call_path_root - root of all call paths.
+ * @call_path: root call path
+ * @blocks: list of blocks to store call paths
+ * @next: next free space
+ * @sz: number of spaces
+ */
+struct call_path_root {
+	struct call_path call_path;
+	struct list_head blocks;
+	size_t next;
+	size_t sz;
+};
+
+struct call_path_root *call_path_root__new(void);
+void call_path_root__free(struct call_path_root *cpr);
+
+struct call_path *call_path__findnew(struct call_path_root *cpr,
+				     struct call_path *parent,
+				     struct symbol *sym, u64 ip, u64 ks);
+
+#endif
diff --git a/tools/perf/util/db-export.c b/tools/perf/util/db-export.c
index 049438d..4fc607c 100644
--- a/tools/perf/util/db-export.c
+++ b/tools/perf/util/db-export.c
@@ -23,6 +23,7 @@
 #include "event.h"
 #include "util.h"
 #include "thread-stack.h"
+#include "call-path.h"
 #include "db-export.h"
 
 struct deferred_export {
diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index 525eb49..7bb8592 100644
--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c
@@ -41,6 +41,7 @@
 #include "../thread-stack.h"
 #include "../trace-event.h"
 #include "../machine.h"
+#include "../call-path.h"
 #include "thread_map.h"
 #include "cpumap.h"
 #include "stat.h"
diff --git a/tools/perf/util/thread-stack.c b/tools/perf/util/thread-stack.c
index 679688e..fc419a5 100644
--- a/tools/perf/util/thread-stack.c
+++ b/tools/perf/util/thread-stack.c
@@ -22,31 +22,9 @@
 #include "debug.h"
 #include "symbol.h"
 #include "comm.h"
+#include "call-path.h"
 #include "thread-stack.h"
 
-#define CALL_PATH_BLOCK_SHIFT 8
-#define CALL_PATH_BLOCK_SIZE (1 << CALL_PATH_BLOCK_SHIFT)
-#define CALL_PATH_BLOCK_MASK (CALL_PATH_BLOCK_SIZE - 1)
-
-struct call_path_block {
-	struct call_path cp[CALL_PATH_BLOCK_SIZE];
-	struct list_head node;
-};
-
-/**
- * struct call_path_root - root of all call paths.
- * @call_path: root call path
- * @blocks: list of blocks to store call paths
- * @next: next free space
- * @sz: number of spaces
- */
-struct call_path_root {
-	struct call_path call_path;
-	struct list_head blocks;
-	size_t next;
-	size_t sz;
-};
-
 /**
  * struct call_return_processor - provides a call-back to consume call-return
  *                                information.
@@ -335,108 +313,6 @@ void thread_stack__sample(struct thread *thread, struct ip_callchain *chain,
 		chain->ips[i] = thread->ts->stack[thread->ts->cnt - i].ret_addr;
 }
 
-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;
-}
-
-static 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;
-}
-
-static 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;
-}
-
-static 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;
-}
-
 struct call_return_processor *
 call_return_processor__new(int (*process)(struct call_return *cr, void *data),
 			   void *data)
diff --git a/tools/perf/util/thread-stack.h b/tools/perf/util/thread-stack.h
index e1528f1..ec9bedd 100644
--- a/tools/perf/util/thread-stack.h
+++ b/tools/perf/util/thread-stack.h
@@ -19,7 +19,6 @@
 #include <sys/types.h>
 
 #include <linux/types.h>
-#include <linux/rbtree.h>
 
 struct thread;
 struct comm;
@@ -30,6 +29,7 @@ struct call_return_processor;
 struct comm;
 struct perf_sample;
 struct addr_location;
+struct call_path;
 
 /*
  * Call/Return flags.
@@ -68,29 +68,6 @@ struct call_return {
 	u32 flags;
 };
 
-/**
- * struct call_path - node in list of calls leading to a function call.
- * @parent: call path to the parent function call
- * @sym: symbol of function called
- * @ip: only if sym is null, the ip of the function
- * @db_id: id used for db-export
- * @in_kernel: whether function is a in the kernel
- * @rb_node: node in parent's tree of called functions
- * @children: tree of call paths of functions called
- *
- * In combination with the call_return structure, the call_path structure
- * defines a context-sensitve call-graph.
- */
-struct call_path {
-	struct call_path *parent;
-	struct symbol *sym;
-	u64 ip;
-	u64 db_id;
-	bool in_kernel;
-	struct rb_node rb_node;
-	struct rb_root children;
-};
-
 int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip,
 			u64 to_ip, u16 insn_len, u64 trace_nr);
 void thread_stack__set_trace_nr(struct thread *thread, u64 trace_nr);
-- 
2.7.4