[PATCH 1/2] tracing: Remove boot tracer
From: Frederic Weisbecker
Date: Wed May 26 2010 - 18:30:49 EST
From: AmÃrico Wang <xiyou.wangcong@xxxxxxxxx>
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@xxxxxxxxx>
Cc: Chase Douglas <chase.douglas@xxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Li Zefan <lizf@xxxxxxxxxxxxxx>
LKML-Reference: <20100526105753.GA5677@xxxxxxxxxxxxxxxxxx>
[ remove the hooks in main.c, and the headers ]
Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
---
include/trace/boot.h | 60 --------------
init/main.c | 27 +++----
kernel/trace/Kconfig | 17 ----
kernel/trace/Makefile | 1 -
kernel/trace/trace.c | 3 -
kernel/trace/trace.h | 8 --
kernel/trace/trace_boot.c | 185 ------------------------------------------
kernel/trace/trace_entries.h | 27 ------
8 files changed, 10 insertions(+), 318 deletions(-)
delete mode 100644 include/trace/boot.h
delete mode 100644 kernel/trace/trace_boot.c
diff --git a/include/trace/boot.h b/include/trace/boot.h
deleted file mode 100644
index 088ea08..0000000
--- a/include/trace/boot.h
+++ /dev/null
@@ -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 */
diff --git a/init/main.c b/init/main.c
index 5c85402..22d5f73 100644
--- a/init/main.c
+++ b/init/main.c
@@ -69,7 +69,6 @@
#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>
@@ -713,38 +712,33 @@ 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));
@@ -758,7 +752,7 @@ int do_one_initcall(initcall_t fn)
printk("initcall %pF returned with %s\n", fn, msgbuf);
}
- return ret.result;
+ return ret;
}
@@ -878,7 +872,6 @@ 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();
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 8b1797c..572992a 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -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
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index ffb1a5b..c3aaeba 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -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
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index ba0ec81..302ec46 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4591,9 +4591,6 @@ __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;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 2cd9639..75a5e80 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -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); \
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
deleted file mode 100644
index c21d5f3..0000000
--- a/kernel/trace/trace_boot.c
+++ /dev/null
@@ -1,185 +0,0 @@
-/*
- * ring buffer based initcalls tracer
- *
- * Copyright (C) 2008 Frederic Weisbecker <fweisbec@xxxxxxxxx>
- *
- */
-
-#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();
-}
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index dc008c1..c293364 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -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
--
1.6.2.3
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