alistair23-linux/tools/perf/util/thread-stack.h
Adrian Hunter 256d92bc93 perf thread-stack: Fix thread stack processing for the idle task
perf creates a single 'struct thread' to represent the idle task. That
is because threads are identified by PID and TID, and the idle task
always has PID == TID == 0.

However, there are actually separate idle tasks for each CPU. That
creates a problem for thread stack processing which assumes that each
thread has a single stack, not one stack per CPU.

Fix that by passing through the CPU number, and in the case of the idle
"thread", pick the thread stack from an array based on the CPU number.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181221120620.9659-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-02 11:03:17 -03:00

103 lines
3 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>
struct thread;
struct comm;
struct ip_callchain;
struct symbol;
struct dso;
struct comm;
struct perf_sample;
struct addr_location;
struct call_path;
/*
* 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_return_processor - provides a call-back to consume call-return
* information.
* @cpr: call path root
* @process: call-back that accepts call/return information
* @data: anonymous data for call-back
*/
struct call_return_processor {
struct call_path_root *cpr;
int (*process)(struct call_return *cr, void *data);
void *data;
};
int thread_stack__event(struct thread *thread, int cpu, u32 flags, u64 from_ip,
u64 to_ip, u16 insn_len, u64 trace_nr);
void thread_stack__set_trace_nr(struct thread *thread, int cpu, u64 trace_nr);
void thread_stack__sample(struct thread *thread, int cpu, struct ip_callchain *chain,
size_t sz, u64 ip, u64 kernel_start);
int thread_stack__flush(struct thread *thread);
void thread_stack__free(struct thread *thread);
size_t thread_stack__depth(struct thread *thread, int cpu);
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