Commit bf2ba0f8 authored by Vincent Donnefort's avatar Vincent Donnefort Committed by Steven Rostedt (Google)
Browse files

tracing: Add init callback to trace remotes 

Add a .init call back so the trace remote callers can add entries to the
tracefs directory.

Link: https://patch.msgid.link/20260309162516.2623589-9-vdonnefort@google.com


Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: default avatarVincent Donnefort <vdonnefort@google.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 330b0cce

include/linux/trace_remote.h

+4 −0
Original line number Diff line number Diff line
@@ -3,10 +3,13 @@ 
#ifndef _LINUX_TRACE_REMOTE_H

#define _LINUX_TRACE_REMOTE_H



#include <linux/dcache.h>

#include <linux/ring_buffer.h>



/**

 * struct trace_remote_callbacks - Callbacks used by Tracefs to control the remote

 * @init:		Called once the remote has been registered. Allows the

 *			caller to extend the Tracefs remote directory

 * @load_trace_buffer:  Called before Tracefs accesses the trace buffer for the first

 *			time. Must return a &trace_buffer_desc

 *			(most likely filled with trace_remote_alloc_buffer())
@@ -22,6 +25,7 @@ 
 *			new reader-page from the @cpu ring-buffer.

 */

struct trace_remote_callbacks {

	int	(*init)(struct dentry *d, void *priv);

	struct trace_buffer_desc *(*load_trace_buffer)(unsigned long size, void *priv);

	void	(*unload_trace_buffer)(struct trace_buffer_desc *desc, void *priv);

	int	(*enable_tracing)(bool enable, void *priv);

kernel/trace/trace_remote.c

+6 −1
Original line number Diff line number Diff line
@@ -863,6 +863,7 @@ static int trace_remote_init_tracefs(const char *name, struct trace_remote *remo 
int trace_remote_register(const char *name, struct trace_remote_callbacks *cbs, void *priv)

{

	struct trace_remote *remote;

	int ret;



	remote = kzalloc_obj(*remote);

	if (!remote)
@@ -880,7 +881,11 @@ int trace_remote_register(const char *name, struct trace_remote_callbacks *cbs, 
		return -ENOMEM;

	}



	return 0;

	ret = cbs->init ? cbs->init(remote->dentry, priv) : 0;

	if (ret)

		pr_err("Init failed for trace remote '%s' (%d)\n", name, ret);



	return ret;

}

EXPORT_SYMBOL_GPL(trace_remote_register);