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* [PATCH] tracing: simplify print_graph_cpu()
@ 2009-07-28 12:26 Lai Jiangshan
  2009-07-28 15:53 ` Frederic Weisbecker
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Lai Jiangshan @ 2009-07-28 12:26 UTC (permalink / raw)
  To: Frederic Weisbecker, Steven Rostedt, Ingo Molnar, LKML


print_graph_cpu() is little over-designed.

And "log10_all" may be wrong when there are holes in cpu_online_mask:
the max online cpu id > cpumask_weight(cpu_online_mask)

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index abf7c4a..e30472d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -183,43 +183,19 @@ static void graph_trace_reset(struct trace_array *tr)
 	unregister_ftrace_graph();
 }
 
-static inline int log10_cpu(int nb)
-{
-	if (nb / 100)
-		return 3;
-	if (nb / 10)
-		return 2;
-	return 1;
-}
+static int max_bytes_for_cpu;
 
 static enum print_line_t
 print_graph_cpu(struct trace_seq *s, int cpu)
 {
-	int i;
 	int ret;
-	int log10_this = log10_cpu(cpu);
-	int log10_all = log10_cpu(cpumask_weight(cpu_online_mask));
-
 
 	/*
 	 * Start with a space character - to make it stand out
 	 * to the right a bit when trace output is pasted into
 	 * email:
 	 */
-	ret = trace_seq_printf(s, " ");
-
-	/*
-	 * Tricky - we space the CPU field according to the max
-	 * number of online CPUs. On a 2-cpu system it would take
-	 * a maximum of 1 digit - on a 128 cpu system it would
-	 * take up to 3 digits:
-	 */
-	for (i = 0; i < log10_all - log10_this; i++) {
-		ret = trace_seq_printf(s, " ");
-		if (!ret)
-			return TRACE_TYPE_PARTIAL_LINE;
-	}
-	ret = trace_seq_printf(s, "%d) ", cpu);
+	ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
 	if (!ret)
 		return TRACE_TYPE_PARTIAL_LINE;
 
@@ -919,6 +895,8 @@ static struct tracer graph_trace __read_mostly = {
 
 static __init int init_graph_trace(void)
 {
+	max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+
 	return register_tracer(&graph_trace);
 }
 





^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH] tracing: simplify print_graph_cpu()
  2009-07-28 12:26 [PATCH] tracing: simplify print_graph_cpu() Lai Jiangshan
@ 2009-07-28 15:53 ` Frederic Weisbecker
  2009-08-02 19:39 ` [tip:tracing/core] tracing: Simplify print_graph_cpu() tip-bot for Lai Jiangshan
  2009-08-06 12:42 ` tip-bot for Lai Jiangshan
  2 siblings, 0 replies; 4+ messages in thread
From: Frederic Weisbecker @ 2009-07-28 15:53 UTC (permalink / raw)
  To: Lai Jiangshan; +Cc: Steven Rostedt, Ingo Molnar, LKML

On Tue, Jul 28, 2009 at 08:26:06PM +0800, Lai Jiangshan wrote:
> 
> print_graph_cpu() is little over-designed.
> 
> And "log10_all" may be wrong when there are holes in cpu_online_mask:
> the max online cpu id > cpumask_weight(cpu_online_mask)
>
> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
> ---
> diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
> index abf7c4a..e30472d 100644
> --- a/kernel/trace/trace_functions_graph.c
> +++ b/kernel/trace/trace_functions_graph.c
> @@ -183,43 +183,19 @@ static void graph_trace_reset(struct trace_array *tr)
>  	unregister_ftrace_graph();
>  }
>  
> -static inline int log10_cpu(int nb)
> -{
> -	if (nb / 100)
> -		return 3;
> -	if (nb / 10)
> -		return 2;
> -	return 1;
> -}
> +static int max_bytes_for_cpu;
>  
>  static enum print_line_t
>  print_graph_cpu(struct trace_seq *s, int cpu)
>  {
> -	int i;
>  	int ret;
> -	int log10_this = log10_cpu(cpu);
> -	int log10_all = log10_cpu(cpumask_weight(cpu_online_mask));
> -
>  
>  	/*
>  	 * Start with a space character - to make it stand out
>  	 * to the right a bit when trace output is pasted into
>  	 * email:
>  	 */
> -	ret = trace_seq_printf(s, " ");
> -
> -	/*
> -	 * Tricky - we space the CPU field according to the max
> -	 * number of online CPUs. On a 2-cpu system it would take
> -	 * a maximum of 1 digit - on a 128 cpu system it would
> -	 * take up to 3 digits:
> -	 */
> -	for (i = 0; i < log10_all - log10_this; i++) {
> -		ret = trace_seq_printf(s, " ");
> -		if (!ret)
> -			return TRACE_TYPE_PARTIAL_LINE;
> -	}
> -	ret = trace_seq_printf(s, "%d) ", cpu);
> +	ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
>  	if (!ret)
>  		return TRACE_TYPE_PARTIAL_LINE;
>  
> @@ -919,6 +895,8 @@ static struct tracer graph_trace __read_mostly = {
>  
>  static __init int init_graph_trace(void)
>  {
> +	max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);


Nice trick :-)

Queued for .32, thanks!



> +
>  	return register_tracer(&graph_trace);
>  }
>  
> 
> 
> 
> 


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [tip:tracing/core] tracing: Simplify print_graph_cpu()
  2009-07-28 12:26 [PATCH] tracing: simplify print_graph_cpu() Lai Jiangshan
  2009-07-28 15:53 ` Frederic Weisbecker
@ 2009-08-02 19:39 ` tip-bot for Lai Jiangshan
  2009-08-06 12:42 ` tip-bot for Lai Jiangshan
  2 siblings, 0 replies; 4+ messages in thread
From: tip-bot for Lai Jiangshan @ 2009-08-02 19:39 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, fweisbec, rostedt, tglx, laijs

Commit-ID:  40699ef64a3203a79d0873da678d0423aa10ae3a
Gitweb:     http://git.kernel.org/tip/40699ef64a3203a79d0873da678d0423aa10ae3a
Author:     Lai Jiangshan <laijs@cn.fujitsu.com>
AuthorDate: Tue, 28 Jul 2009 20:26:06 +0800
Committer:  Frederic Weisbecker <fweisbec@gmail.com>
CommitDate: Wed, 29 Jul 2009 01:04:32 +0200

tracing: Simplify print_graph_cpu()

print_graph_cpu() is little over-designed.

And "log10_all" may be wrong when there are holes in cpu_online_mask:
the max online cpu id > cpumask_weight(cpu_online_mask)

So change it by using a static column length for the cpu matching
nr_cpu_ids number of decimal characters.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4A6EEE5E.2000001@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>


---
 kernel/trace/trace_functions_graph.c |   30 ++++--------------------------
 1 files changed, 4 insertions(+), 26 deletions(-)

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index abf7c4a..e30472d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -183,43 +183,19 @@ static void graph_trace_reset(struct trace_array *tr)
 	unregister_ftrace_graph();
 }
 
-static inline int log10_cpu(int nb)
-{
-	if (nb / 100)
-		return 3;
-	if (nb / 10)
-		return 2;
-	return 1;
-}
+static int max_bytes_for_cpu;
 
 static enum print_line_t
 print_graph_cpu(struct trace_seq *s, int cpu)
 {
-	int i;
 	int ret;
-	int log10_this = log10_cpu(cpu);
-	int log10_all = log10_cpu(cpumask_weight(cpu_online_mask));
-
 
 	/*
 	 * Start with a space character - to make it stand out
 	 * to the right a bit when trace output is pasted into
 	 * email:
 	 */
-	ret = trace_seq_printf(s, " ");
-
-	/*
-	 * Tricky - we space the CPU field according to the max
-	 * number of online CPUs. On a 2-cpu system it would take
-	 * a maximum of 1 digit - on a 128 cpu system it would
-	 * take up to 3 digits:
-	 */
-	for (i = 0; i < log10_all - log10_this; i++) {
-		ret = trace_seq_printf(s, " ");
-		if (!ret)
-			return TRACE_TYPE_PARTIAL_LINE;
-	}
-	ret = trace_seq_printf(s, "%d) ", cpu);
+	ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
 	if (!ret)
 		return TRACE_TYPE_PARTIAL_LINE;
 
@@ -919,6 +895,8 @@ static struct tracer graph_trace __read_mostly = {
 
 static __init int init_graph_trace(void)
 {
+	max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+
 	return register_tracer(&graph_trace);
 }
 

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [tip:tracing/core] tracing: Simplify print_graph_cpu()
  2009-07-28 12:26 [PATCH] tracing: simplify print_graph_cpu() Lai Jiangshan
  2009-07-28 15:53 ` Frederic Weisbecker
  2009-08-02 19:39 ` [tip:tracing/core] tracing: Simplify print_graph_cpu() tip-bot for Lai Jiangshan
@ 2009-08-06 12:42 ` tip-bot for Lai Jiangshan
  2 siblings, 0 replies; 4+ messages in thread
From: tip-bot for Lai Jiangshan @ 2009-08-06 12:42 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, fweisbec, rostedt, tglx, laijs

Commit-ID:  0c9e6f639aed490202bbc79214f4495cf4bfde58
Gitweb:     http://git.kernel.org/tip/0c9e6f639aed490202bbc79214f4495cf4bfde58
Author:     Lai Jiangshan <laijs@cn.fujitsu.com>
AuthorDate: Tue, 28 Jul 2009 20:26:06 +0800
Committer:  Frederic Weisbecker <fweisbec@gmail.com>
CommitDate: Thu, 6 Aug 2009 07:28:04 +0200

tracing: Simplify print_graph_cpu()

print_graph_cpu() is little over-designed.

And "log10_all" may be wrong when there are holes in cpu_online_mask:
the max online cpu id > cpumask_weight(cpu_online_mask)

So change it by using a static column length for the cpu matching
nr_cpu_ids number of decimal characters.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4A6EEE5E.2000001@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>


---
 kernel/trace/trace_functions_graph.c |   30 ++++--------------------------
 1 files changed, 4 insertions(+), 26 deletions(-)

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index abf7c4a..e30472d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -183,43 +183,19 @@ static void graph_trace_reset(struct trace_array *tr)
 	unregister_ftrace_graph();
 }
 
-static inline int log10_cpu(int nb)
-{
-	if (nb / 100)
-		return 3;
-	if (nb / 10)
-		return 2;
-	return 1;
-}
+static int max_bytes_for_cpu;
 
 static enum print_line_t
 print_graph_cpu(struct trace_seq *s, int cpu)
 {
-	int i;
 	int ret;
-	int log10_this = log10_cpu(cpu);
-	int log10_all = log10_cpu(cpumask_weight(cpu_online_mask));
-
 
 	/*
 	 * Start with a space character - to make it stand out
 	 * to the right a bit when trace output is pasted into
 	 * email:
 	 */
-	ret = trace_seq_printf(s, " ");
-
-	/*
-	 * Tricky - we space the CPU field according to the max
-	 * number of online CPUs. On a 2-cpu system it would take
-	 * a maximum of 1 digit - on a 128 cpu system it would
-	 * take up to 3 digits:
-	 */
-	for (i = 0; i < log10_all - log10_this; i++) {
-		ret = trace_seq_printf(s, " ");
-		if (!ret)
-			return TRACE_TYPE_PARTIAL_LINE;
-	}
-	ret = trace_seq_printf(s, "%d) ", cpu);
+	ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
 	if (!ret)
 		return TRACE_TYPE_PARTIAL_LINE;
 
@@ -919,6 +895,8 @@ static struct tracer graph_trace __read_mostly = {
 
 static __init int init_graph_trace(void)
 {
+	max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+
 	return register_tracer(&graph_trace);
 }
 

^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2009-08-06 12:43 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-07-28 12:26 [PATCH] tracing: simplify print_graph_cpu() Lai Jiangshan
2009-07-28 15:53 ` Frederic Weisbecker
2009-08-02 19:39 ` [tip:tracing/core] tracing: Simplify print_graph_cpu() tip-bot for Lai Jiangshan
2009-08-06 12:42 ` tip-bot for Lai Jiangshan

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