# Re: \[PATCH v12 07/11\] perf: Support deferred user callchains for per CPU events

- From: Jens Remus \<hidden\>
- Date: 2025-07-02 12:20:52 
- List: linux-trace-kernel
- Page: https://ratatoskr.run/linux-trace-kernel/2025/07/3117499
- Thread: https://ratatoskr.run/linux-trace-kernel/2025/07/3116251/t.md

```text
Hello Steve!

On 01.07.2025 20:04, Steven Rostedt wrote:

> diff --git a/kernel/events/core.c b/kernel/events/core.c

> @@ -5609,62 +5784,119 @@ static void perf_pending_unwind_sync(struct perf_event *event)
>  
>  struct perf_callchain_deferred_event {
>  	struct perf_event_header	header;
> +	u64				timestamp;
>  	u64				nr;
>  	u64				ips[];
>  };

Nit: Please update the following related comments when making changes to
struct perf_callchain_deferred_event.

diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 184740d1e79d..08ce721e79bc 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -1248,6 +1248,7 @@ enum perf_event_type {
 	 *
 	 * struct {
 	 *	struct perf_event_header	header;
+	 *	u64				timestamp;
 	 *	u64				nr;
 	 *	u64				ips[nr];
 	 *	struct sample_id		sample_id;
diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
index 184740d1e79d..08ce721e79bc 100644
--- a/tools/include/uapi/linux/perf_event.h
+++ b/tools/include/uapi/linux/perf_event.h
@@ -1248,6 +1248,7 @@ enum perf_event_type {
 	 *
 	 * struct {
 	 *	struct perf_event_header	header;
+	 *	u64				timestamp;
 	 *	u64				nr;
 	 *	u64				ips[nr];
 	 *	struct sample_id		sample_id;

Thanks and regards,
Jens
-- 
Jens Remus
Linux on Z Development (D3303)
+49-7031-16-1128 Office
jremus@de.ibm.com

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```