alistair23-linux/tools/perf/util/thread-stack.h
Adrian Hunter 92a9e4f7db perf tools: Enhance the thread stack to output call/return data
Enhance the thread stack to output detailed information about paired
calls and returns.

The enhanced processing consumes sample information via
thread_stack__process() and outputs information about paired calls /
returns via a call-back.

While the call-back makes it possible for the facility to be used by
arbitrary tools, a subsequent patch will provide the information to
Python scripting via the db-export interface.

An important part of the call/return information is the
call path which provides a structure that defines a context
sensitive call graph.

Note that there are now two ways to use the thread stack.

For simply providing a call stack (like you would get from the perf
record -g option) the interface consists of thread_stack__event() and
thread_stack__sample().

Whereas the enhanced interface consists of call_return_processor__new()
and thread_stack__process().

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1414678188-14946-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-11-03 17:43:56 -03:00

112 lines
3.2 KiB
C

/*
* thread-stack.h: Synthesize a thread's stack using call / return events
* 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_THREAD_STACK_H
#define __PERF_THREAD_STACK_H
#include <sys/types.h>
#include <linux/types.h>
#include <linux/rbtree.h>
struct thread;
struct comm;
struct ip_callchain;
struct symbol;
struct dso;
struct call_return_processor;
struct comm;
struct perf_sample;
struct addr_location;
/*
* Call/Return flags.
*
* CALL_RETURN_NO_CALL: 'return' but no matching 'call'
* CALL_RETURN_NO_RETURN: 'call' but no matching 'return'
*/
enum {
CALL_RETURN_NO_CALL = 1 << 0,
CALL_RETURN_NO_RETURN = 1 << 1,
};
/**
* struct call_return - paired call/return information.
* @thread: thread in which call/return occurred
* @comm: comm in which call/return occurred
* @cp: call path
* @call_time: timestamp of call (if known)
* @return_time: timestamp of return (if known)
* @branch_count: number of branches seen between call and return
* @call_ref: external reference to 'call' sample (e.g. db_id)
* @return_ref: external reference to 'return' sample (e.g. db_id)
* @db_id: id used for db-export
* @flags: Call/Return flags
*/
struct call_return {
struct thread *thread;
struct comm *comm;
struct call_path *cp;
u64 call_time;
u64 return_time;
u64 branch_count;
u64 call_ref;
u64 return_ref;
u64 db_id;
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);
void thread_stack__sample(struct thread *thread, struct ip_callchain *chain,
size_t sz, u64 ip);
void thread_stack__free(struct thread *thread);
struct call_return_processor *
call_return_processor__new(int (*process)(struct call_return *cr, void *data),
void *data);
void call_return_processor__free(struct call_return_processor *crp);
int thread_stack__process(struct thread *thread, struct comm *comm,
struct perf_sample *sample,
struct addr_location *from_al,
struct addr_location *to_al, u64 ref,
struct call_return_processor *crp);
#endif