mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
* [PATCH v2] tracing: Point constant hist field type to string literal
@ 2026-05-27  2:34 Yu Peng
  2026-05-27  2:41 ` Masami Hiramatsu
  0 siblings, 1 reply; 4+ messages in thread
From: Yu Peng @ 2026-05-27  2:34 UTC (permalink / raw)
  To: rostedt
  Cc: linux-kernel, linux-trace-kernel, mathieu.desnoyers, mhiramat, pengyu

The HIST_FIELD_FL_CONST path uses the fixed "u64" type string.

Point hist_field->type directly to the string literal, matching the
HIST_FIELD_FL_HITCOUNT path. The release path already uses kfree_const(),
so no duplication is needed.

Signed-off-by: Yu Peng <pengyu@kylinos.cn>
---
Changes in v2:
- Point hist_field->type directly to "u64" as suggested.

 kernel/trace/trace_events_hist.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index eb2c2bc8bc3d5..b50f2bd5ff771 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1992,9 +1992,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (flags & HIST_FIELD_FL_CONST) {
 		hist_field->fn_num = HIST_FIELD_FN_CONST;
 		hist_field->size = sizeof(u64);
-		hist_field->type = kstrdup("u64", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "u64";
 		goto out;
 	}
 
-- 
2.43.0

^ permalink raw reply	[flat|nested] 4+ messages in thread
* Re: [PATCH v2] tracing: Point constant hist field type to string literal
  2026-05-27  2:34 [PATCH v2] tracing: Point constant hist field type to string literal Yu Peng
@ 2026-05-27  2:41 ` Masami Hiramatsu
  0 siblings, 0 replies; 4+ messages in thread
From: Masami Hiramatsu @ 2026-05-27  2:41 UTC (permalink / raw)
  To: Yu Peng
  Cc: rostedt, linux-kernel, linux-trace-kernel, mathieu.desnoyers, mhiramat

On Wed, 27 May 2026 10:34:50 +0800
Yu Peng <pengyu@kylinos.cn> wrote:

> The HIST_FIELD_FL_CONST path uses the fixed "u64" type string.
> 
> Point hist_field->type directly to the string literal, matching the
> HIST_FIELD_FL_HITCOUNT path. The release path already uses kfree_const(),
> so no duplication is needed.
> 
> Signed-off-by: Yu Peng <pengyu@kylinos.cn>

This looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thanks,

> ---
> Changes in v2:
> - Point hist_field->type directly to "u64" as suggested.
> 
>  kernel/trace/trace_events_hist.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
> index eb2c2bc8bc3d5..b50f2bd5ff771 100644
> --- a/kernel/trace/trace_events_hist.c
> +++ b/kernel/trace/trace_events_hist.c
> @@ -1992,9 +1992,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
>  	if (flags & HIST_FIELD_FL_CONST) {
>  		hist_field->fn_num = HIST_FIELD_FN_CONST;
>  		hist_field->size = sizeof(u64);
> -		hist_field->type = kstrdup("u64", GFP_KERNEL);
> -		if (!hist_field->type)
> -			goto free;
> +		hist_field->type = "u64";
>  		goto out;
>  	}
>  
> -- 
> 2.43.0


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>

^ permalink raw reply	[flat|nested] 4+ messages in thread
* Re: [PATCH v2] tracing: Point constant hist field type to string literal
  2026-05-27  2:18 ` [PATCH v2] tracing: Point constant hist field type to string literal Yu Peng
@ 2026-05-27  2:26   ` Steven Rostedt
  0 siblings, 0 replies; 4+ messages in thread
From: Steven Rostedt @ 2026-05-27  2:26 UTC (permalink / raw)
  To: Yu Peng; +Cc: linux-kernel, linux-trace-kernel, mathieu.desnoyers, mhiramat

On Wed, 27 May 2026 10:18:27 +0800
Yu Peng <pengyu@kylinos.cn> wrote:

> The HIST_FIELD_FL_CONST path uses the fixed "u64" type string.
> 
> Point hist_field->type directly to the string literal, matching the
> HIST_FIELD_FL_HITCOUNT path. The release path already uses kfree_const(),
> so no duplication is needed.
> 
> Signed-off-by: Yu Peng <pengyu@kylinos.cn>
> ---
> Changes in v2:
> - Point hist_field->type directly to "u64" as suggested

All new versions of a patch need to start a new thread. Please resend
this as a new thread and not a reply.

-- Steve


> 
>  kernel/trace/trace_events_hist.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
> index eb2c2bc8bc3d5..b50f2bd5ff771 100644
> --- a/kernel/trace/trace_events_hist.c
> +++ b/kernel/trace/trace_events_hist.c
> @@ -1992,9 +1992,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
>  	if (flags & HIST_FIELD_FL_CONST) {
>  		hist_field->fn_num = HIST_FIELD_FN_CONST;
>  		hist_field->size = sizeof(u64);
> -		hist_field->type = kstrdup("u64", GFP_KERNEL);
> -		if (!hist_field->type)
> -			goto free;
> +		hist_field->type = "u64";
>  		goto out;
>  	}
>  


^ permalink raw reply	[flat|nested] 4+ messages in thread
* [PATCH v2] tracing: Point constant hist field type to string literal
  2026-05-27  1:50 [PATCH] tracing: Use kstrdup_const() for constant hist field type Steven Rostedt
@ 2026-05-27  2:18 ` Yu Peng
  2026-05-27  2:26   ` Steven Rostedt
  0 siblings, 1 reply; 4+ messages in thread
From: Yu Peng @ 2026-05-27  2:18 UTC (permalink / raw)
  To: rostedt
  Cc: linux-kernel, linux-trace-kernel, mathieu.desnoyers, mhiramat, pengyu

The HIST_FIELD_FL_CONST path uses the fixed "u64" type string.

Point hist_field->type directly to the string literal, matching the
HIST_FIELD_FL_HITCOUNT path. The release path already uses kfree_const(),
so no duplication is needed.

Signed-off-by: Yu Peng <pengyu@kylinos.cn>
---
Changes in v2:
- Point hist_field->type directly to "u64" as suggested.

 kernel/trace/trace_events_hist.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index eb2c2bc8bc3d5..b50f2bd5ff771 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1992,9 +1992,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (flags & HIST_FIELD_FL_CONST) {
 		hist_field->fn_num = HIST_FIELD_FN_CONST;
 		hist_field->size = sizeof(u64);
-		hist_field->type = kstrdup("u64", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "u64";
 		goto out;
 	}
 
-- 
2.43.0

^ permalink raw reply	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2026-05-27  2:41 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2026-05-27  2:34 [PATCH v2] tracing: Point constant hist field type to string literal Yu Peng
2026-05-27  2:41 ` Masami Hiramatsu
  -- strict thread matches above, loose matches on Subject: below --
2026-05-27  1:50 [PATCH] tracing: Use kstrdup_const() for constant hist field type Steven Rostedt
2026-05-27  2:18 ` [PATCH v2] tracing: Point constant hist field type to string literal Yu Peng
2026-05-27  2:26   ` Steven Rostedt

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®