Commit 07c65f4d authored by zhangwei(Jovi)'s avatar zhangwei(Jovi) Committed by Linus Torvalds
Browse files

printk/tracing: rework console tracing 



Commit 7ff9554b ("printk: convert byte-buffer to variable-length
record buffer") removed start and end parameters from
call_console_drivers, but those parameters still exist in
include/trace/events/printk.h.

Without start and end parameters handling, printk tracing became more
simple as: trace_console(text, len);

Signed-off-by: default avatarzhangwei(Jovi) <jovi.zhangwei@huawei.com>
Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2fb0815c

include/trace/events/printk.h

+6 −19
Original line number Diff line number Diff line
@@ -6,31 +6,18 @@ 


#include <linux/tracepoint.h>



TRACE_EVENT_CONDITION(console,

	TP_PROTO(const char *log_buf, unsigned start, unsigned end,

		 unsigned log_buf_len),

TRACE_EVENT(console,

	TP_PROTO(const char *text, size_t len),



	TP_ARGS(log_buf, start, end, log_buf_len),



	TP_CONDITION(start != end),

	TP_ARGS(text, len),



	TP_STRUCT__entry(

		__dynamic_array(char, msg, end - start + 1)

		__dynamic_array(char, msg, len + 1)

	),



	TP_fast_assign(

		if ((start & (log_buf_len - 1)) > (end & (log_buf_len - 1))) {

			memcpy(__get_dynamic_array(msg),

			       log_buf + (start & (log_buf_len - 1)),

			       log_buf_len - (start & (log_buf_len - 1)));

			memcpy((char *)__get_dynamic_array(msg) +

			       log_buf_len - (start & (log_buf_len - 1)),

			       log_buf, end & (log_buf_len - 1));

		} else

			memcpy(__get_dynamic_array(msg),

			       log_buf + (start & (log_buf_len - 1)),

			       end - start);

		((char *)__get_dynamic_array(msg))[end - start] = 0;

		memcpy(__get_dynamic_array(msg), text, len);

		((char *)__get_dynamic_array(msg))[len] = 0;

	),



	TP_printk("%s", __get_str(msg))

kernel/printk.c

+1 −1
Original line number Diff line number Diff line
@@ -1265,7 +1265,7 @@ static void call_console_drivers(int level, const char *text, size_t len) 
{

	struct console *con;



	trace_console(text, 0, len, len);

	trace_console(text, len);



	if (level >= console_loglevel && !ignore_loglevel)

		return;

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