Commit 07c17732 authored by Tetsuo Handa's avatar Tetsuo Handa Committed by Petr Mladek
Browse files

printk: Remove print_prefix() calls with NULL buffer. 

We can save lines/size by removing print_prefix() with buf == NULL.
This patch makes no functional change.

Link: http://lkml.kernel.org/r/1544521745-11925-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp


To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
parent e80c1a9d

kernel/printk/printk.c

+14 −25
Original line number Original line Diff line number Diff line
@@ -1228,13 +1228,15 @@ static inline void boot_delay_msec(int level) 
static bool printk_time = IS_ENABLED(CONFIG_PRINTK_TIME);

static bool printk_time = IS_ENABLED(CONFIG_PRINTK_TIME);

module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);

module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);





static size_t print_syslog(unsigned int level, char *buf)

{

	return sprintf(buf, "<%u>", level);

}



static size_t print_time(u64 ts, char *buf)

static size_t print_time(u64 ts, char *buf)

{

{

	unsigned long rem_nsec = do_div(ts, 1000000000);

	unsigned long rem_nsec = do_div(ts, 1000000000);





	if (!buf)

		return snprintf(NULL, 0, "[%5lu.000000] ", (unsigned long)ts);



	return sprintf(buf, "[%5lu.%06lu] ",

	return sprintf(buf, "[%5lu.%06lu] ",

		       (unsigned long)ts, rem_nsec / 1000);

		       (unsigned long)ts, rem_nsec / 1000);

}

}
@@ -1243,24 +1245,11 @@ static size_t print_prefix(const struct printk_log *msg, bool syslog, 
			   bool time, char *buf)

			   bool time, char *buf)

{

{

	size_t len = 0;

	size_t len = 0;

	unsigned int prefix = (msg->facility << 3) | msg->level;



	if (syslog) {

		if (buf) {

			len += sprintf(buf, "<%u>", prefix);

		} else {

			len += 3;

			if (prefix > 999)

				len += 3;

			else if (prefix > 99)

				len += 2;

			else if (prefix > 9)

				len++;

		}

	}





	if (syslog)

		len = print_syslog((msg->facility << 3) | msg->level, buf);

	if (time)

	if (time)

		len += print_time(msg->ts_nsec, buf ? buf + len : NULL);

		len += print_time(msg->ts_nsec, buf + len);

	return len;

	return len;

}

}
@@ -1270,6 +1259,8 @@ static size_t msg_print_text(const struct printk_log *msg, bool syslog, 
	const char *text = log_text(msg);

	const char *text = log_text(msg);

	size_t text_size = msg->text_len;

	size_t text_size = msg->text_len;

	size_t len = 0;

	size_t len = 0;

	char prefix[PREFIX_MAX];

	const size_t prefix_len = print_prefix(msg, syslog, time, prefix);





	do {

	do {

		const char *next = memchr(text, '\n', text_size);

		const char *next = memchr(text, '\n', text_size);
@@ -1284,19 +1275,17 @@ static size_t msg_print_text(const struct printk_log *msg, bool syslog, 
		}

		}





		if (buf) {

		if (buf) {

			if (print_prefix(msg, syslog, time, NULL) +

			if (prefix_len + text_len + 1 >= size - len)

			    text_len + 1 >= size - len)

				break;

				break;





			len += print_prefix(msg, syslog, time, buf + len);

			memcpy(buf + len, prefix, prefix_len);

			len += prefix_len;

			memcpy(buf + len, text, text_len);

			memcpy(buf + len, text, text_len);

			len += text_len;

			len += text_len;

			buf[len++] = '\n';

			buf[len++] = '\n';

		} else {

		} else {

			/* SYSLOG_ACTION_* buffer size only calculation */

			/* SYSLOG_ACTION_* buffer size only calculation */

			len += print_prefix(msg, syslog, time, NULL);

			len += prefix_len + text_len + 1;

			len += text_len;

			len++;

		}

		}





		text = next;

		text = next;

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