tracing: Remove boot tracer

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 <[email protected]> Cc: Chase Douglas <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Li Zefan <[email protected]> LKML-Reference: <[email protected]> [ remove the hooks in main.c, and the headers ] Signed-off-by: Frederic Weisbecker <[email protected]>
josf · Jun 8, 2010 · 30dbb20 · 30dbb20
1 parent b0f82b8
commit 30dbb20
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Showing 8 changed files with 10 additions and 318 deletions.
diff --git a/include/trace/boot.h b/include/trace/boot.h
diff --git a/init/main.c b/init/main.c
@@ -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();

diff --git 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
@@ -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
@@ -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;
 

diff --git 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