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tracing: Remove boot tracer

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The boot tracer is useless. It simply logs the initcalls
but in fact these initcalls are also logged through printk
while using the initcall_debug kernel parameter.

Nobody seem to be using it so far. Then just remove it.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Chase Douglas <chase.douglas@canonical.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <20100526105753.GA5677@cr0.nay.redhat.com>
[ remove the hooks in main.c, and the headers ]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
This commit is contained in:
Américo Wang 2010-05-26 18:57:53 +08:00 • committed by Frederic Weisbecker
commit 30dbb20e68
8 changed files with 10 additions and 318 deletions
Download patch file Download diff file Expand all files Collapse all files

60
include/trace/boot.h
View file

@ -1,60 +0,0 @@
#ifndef _LINUX_TRACE_BOOT_H
#define _LINUX_TRACE_BOOT_H
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/init.h>
/*
* Structure which defines the trace of an initcall
* while it is called.
* You don't have to fill the func field since it is
* only used internally by the tracer.
*/
struct boot_trace_call {
pid_t caller;
char func[KSYM_SYMBOL_LEN];
};
/*
* Structure which defines the trace of an initcall
* while it returns.
*/
struct boot_trace_ret {
char func[KSYM_SYMBOL_LEN];
int result;
unsigned long long duration; /* nsecs */
};
#ifdef CONFIG_BOOT_TRACER
/* Append the traces on the ring-buffer */
extern void trace_boot_call(struct boot_trace_call *bt, initcall_t fn);
extern void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn);
/* Tells the tracer that smp_pre_initcall is finished.
* So we can start the tracing
*/
extern void start_boot_trace(void);
/* Resume the tracing of other necessary events
* such as sched switches
*/
extern void enable_boot_trace(void);
/* Suspend this tracing. Actually, only sched_switches tracing have
* to be suspended. Initcalls doesn't need it.)
*/
extern void disable_boot_trace(void);
#else
static inline
void trace_boot_call(struct boot_trace_call *bt, initcall_t fn) { }
static inline
void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn) { }
static inline void start_boot_trace(void) { }
static inline void enable_boot_trace(void) { }
static inline void disable_boot_trace(void) { }
#endif /* CONFIG_BOOT_TRACER */
#endif /* __LINUX_TRACE_BOOT_H */

27
init/main.c
View file

@ -70,7 +70,6 @@
#include <linux/sfi.h>
#include <linux/shmem_fs.h>
#include <linux/slab.h>
#include <trace/boot.h>
#include <asm/io.h>
#include <asm/bugs.h>
@ -715,38 +714,33 @@ int initcall_debug;
core_param(initcall_debug, initcall_debug, bool, 0644);
static char msgbuf[64];
static struct boot_trace_call call;
static struct boot_trace_ret ret;
int do_one_initcall(initcall_t fn)
{
int count = preempt_count();
ktime_t calltime, delta, rettime;
unsigned long long duration;
int ret;
if (initcall_debug) {
call.caller = task_pid_nr(current);
printk("calling %pF @ %i\n", fn, call.caller);
printk("calling %pF @ %i\n", fn, task_pid_nr(current));
calltime = ktime_get();
trace_boot_call(&call, fn);
enable_boot_trace();
}
ret.result = fn();
ret = fn();
if (initcall_debug) {
disable_boot_trace();
rettime = ktime_get();
delta = ktime_sub(rettime, calltime);
ret.duration = (unsigned long long) ktime_to_ns(delta) >> 10;
trace_boot_ret(&ret, fn);
printk("initcall %pF returned %d after %Ld usecs\n", fn,
ret.result, ret.duration);
duration = (unsigned long long) ktime_to_ns(delta) >> 10;
printk("initcall %pF returned %d after %lld usecs\n", fn,
ret, duration);
}
msgbuf[0] = 0;
if (ret.result && ret.result != -ENODEV && initcall_debug)
sprintf(msgbuf, "error code %d ", ret.result);
if (ret && ret != -ENODEV && initcall_debug)
sprintf(msgbuf, "error code %d ", ret);
if (preempt_count() != count) {
strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
@ -760,7 +754,7 @@ int do_one_initcall(initcall_t fn)
printk("initcall %pF returned with %s\n", fn, msgbuf);
}
return ret.result;
return ret;
}
@ -880,7 +874,6 @@ static int __init kernel_init(void * unused)
smp_prepare_cpus(setup_max_cpus);
do_pre_smp_initcalls();
start_boot_trace();
smp_init();
sched_init_smp();

17
kernel/trace/Kconfig
View file

@ -229,23 +229,6 @@ config FTRACE_SYSCALLS
help
Basic tracer to catch the syscall entry and exit events.
config BOOT_TRACER
bool "Trace boot initcalls"
select GENERIC_TRACER
select CONTEXT_SWITCH_TRACER
help
This tracer helps developers to optimize boot times: it records
the timings of the initcalls and traces key events and the identity
of tasks that can cause boot delays, such as context-switches.
Its aim is to be parsed by the scripts/bootgraph.pl tool to
produce pretty graphics about boot inefficiencies, giving a visual
representation of the delays during initcalls - but the raw
/debug/tracing/trace text output is readable too.
You must pass in initcall_debug and ftrace=initcall to the kernel
command line to enable this on bootup.
config TRACE_BRANCH_PROFILING
bool
select GENERIC_TRACER

1
kernel/trace/Makefile
View file

@ -38,7 +38,6 @@ obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
obj-$(CONFIG_NOP_TRACER) += trace_nop.o
obj-$(CONFIG_STACK_TRACER) += trace_stack.o
obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
obj-$(CONFIG_BOOT_TRACER) += trace_boot.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
obj-$(CONFIG_KMEMTRACE) += kmemtrace.o

3
kernel/trace/trace.c
View file

@ -4603,9 +4603,6 @@ __init static int tracer_alloc_buffers(void)
register_tracer(&nop_trace);
current_trace = &nop_trace;
#ifdef CONFIG_BOOT_TRACER
register_tracer(&boot_tracer);
#endif
/* All seems OK, enable tracing */
tracing_disabled = 0;

8
kernel/trace/trace.h
View file

@ -9,10 +9,8 @@
#include <linux/mmiotrace.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
#include <trace/boot.h>
#include <linux/kmemtrace.h>
#include <linux/hw_breakpoint.h>
#include <linux/trace_seq.h>
#include <linux/ftrace_event.h>
@ -29,8 +27,6 @@ enum trace_type {
TRACE_MMIO_RW,
TRACE_MMIO_MAP,
TRACE_BRANCH,
TRACE_BOOT_CALL,
TRACE_BOOT_RET,
TRACE_GRAPH_RET,
TRACE_GRAPH_ENT,
TRACE_USER_STACK,
@ -48,8 +44,6 @@ enum kmemtrace_type_id {
KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */
};
extern struct tracer boot_tracer;
#undef __field
#define __field(type, item) type item;
@ -209,8 +203,6 @@ extern void __ftrace_bad_type(void);
TRACE_MMIO_RW); \
IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
TRACE_MMIO_MAP); \
IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
TRACE_GRAPH_ENT); \

185
kernel/trace/trace_boot.c
View file

@ -1,185 +0,0 @@
/*
* ring buffer based initcalls tracer
*
* Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
*
*/
#include <linux/init.h>
#include <linux/debugfs.h>
#include <linux/ftrace.h>
#include <linux/kallsyms.h>
#include <linux/time.h>
#include "trace.h"
#include "trace_output.h"
static struct trace_array *boot_trace;
static bool pre_initcalls_finished;
/* Tells the boot tracer that the pre_smp_initcalls are finished.
* So we are ready .
* It doesn't enable sched events tracing however.
* You have to call enable_boot_trace to do so.
*/
void start_boot_trace(void)
{
pre_initcalls_finished = true;
}
void enable_boot_trace(void)
{
if (boot_trace && pre_initcalls_finished)
tracing_start_sched_switch_record();
}
void disable_boot_trace(void)
{
if (boot_trace && pre_initcalls_finished)
tracing_stop_sched_switch_record();
}
static int boot_trace_init(struct trace_array *tr)
{
boot_trace = tr;
if (!tr)
return 0;
tracing_reset_online_cpus(tr);
tracing_sched_switch_assign_trace(tr);
return 0;
}
static enum print_line_t
initcall_call_print_line(struct trace_iterator *iter)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct trace_boot_call *field;
struct boot_trace_call *call;
u64 ts;
unsigned long nsec_rem;
int ret;
trace_assign_type(field, entry);
call = &field->boot_call;
ts = iter->ts;
nsec_rem = do_div(ts, NSEC_PER_SEC);
ret = trace_seq_printf(s, "[%5ld.%09ld] calling %s @ %i\n",
(unsigned long)ts, nsec_rem, call->func, call->caller);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
else
return TRACE_TYPE_HANDLED;
}
static enum print_line_t
initcall_ret_print_line(struct trace_iterator *iter)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct trace_boot_ret *field;
struct boot_trace_ret *init_ret;
u64 ts;
unsigned long nsec_rem;
int ret;
trace_assign_type(field, entry);
init_ret = &field->boot_ret;
ts = iter->ts;
nsec_rem = do_div(ts, NSEC_PER_SEC);
ret = trace_seq_printf(s, "[%5ld.%09ld] initcall %s "
"returned %d after %llu msecs\n",
(unsigned long) ts,
nsec_rem,
init_ret->func, init_ret->result, init_ret->duration);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
else
return TRACE_TYPE_HANDLED;
}
static enum print_line_t initcall_print_line(struct trace_iterator *iter)
{
struct trace_entry *entry = iter->ent;
switch (entry->type) {
case TRACE_BOOT_CALL:
return initcall_call_print_line(iter);
case TRACE_BOOT_RET:
return initcall_ret_print_line(iter);
default:
return TRACE_TYPE_UNHANDLED;
}
}
struct tracer boot_tracer __read_mostly =
{
.name = "initcall",
.init = boot_trace_init,
.reset = tracing_reset_online_cpus,
.print_line = initcall_print_line,
};
void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
{
struct ftrace_event_call *call = &event_boot_call;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct trace_boot_call *entry;
struct trace_array *tr = boot_trace;
if (!tr || !pre_initcalls_finished)
return;
/* Get its name now since this function could
* disappear because it is in the .init section.
*/
sprint_symbol(bt->func, (unsigned long)fn);
preempt_disable();
buffer = tr->buffer;
event = trace_buffer_lock_reserve(buffer, TRACE_BOOT_CALL,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->boot_call = *bt;
if (!filter_check_discard(call, entry, buffer, event))
trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
{
struct ftrace_event_call *call = &event_boot_ret;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct trace_boot_ret *entry;
struct trace_array *tr = boot_trace;
if (!tr || !pre_initcalls_finished)
return;
sprint_symbol(bt->func, (unsigned long)fn);
preempt_disable();
buffer = tr->buffer;
event = trace_buffer_lock_reserve(buffer, TRACE_BOOT_RET,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->boot_ret = *bt;
if (!filter_check_discard(call, entry, buffer, event))
trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}

27
kernel/trace/trace_entries.h
View file

@ -271,33 +271,6 @@ FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map,
__entry->map_id, __entry->opcode)
);
FTRACE_ENTRY(boot_call, trace_boot_call,
TRACE_BOOT_CALL,
F_STRUCT(
__field_struct( struct boot_trace_call, boot_call )
__field_desc( pid_t, boot_call, caller )
__array_desc( char, boot_call, func, KSYM_SYMBOL_LEN)
),
F_printk("%d %s", __entry->caller, __entry->func)
);
FTRACE_ENTRY(boot_ret, trace_boot_ret,
TRACE_BOOT_RET,
F_STRUCT(
__field_struct( struct boot_trace_ret, boot_ret )
__array_desc( char, boot_ret, func, KSYM_SYMBOL_LEN)
__field_desc( int, boot_ret, result )
__field_desc( unsigned long, boot_ret, duration )
),
F_printk("%s %d %lx",
__entry->func, __entry->result, __entry->duration)
);
#define TRACE_FUNC_SIZE 30
#define TRACE_FILE_SIZE 20