Commit ac60ad74 authored by Nick Andrew's avatar Nick Andrew Committed by Thomas Gleixner
Browse files

printk: refactor processing of line severity tokens 



Restructure the logic of vprintk() so the processing of the leading
3 characters of each input line is in one place, regardless whether
printk_time is enabled. This makes the code smaller and easier to
understand.

size reduction in kernel/printk.o:

   text	   data	    bss	    dec	    hex	filename
   6157	    397	1049804	1056358	 101e66	printk.o.before
   6117	    397	1049804	1056318	 101e3e	printk.o.after

and some style uncleanlinesses removed as well as a side-effect:

 Before:
    total: 19 errors, 22 warnings, 1340 lines checked
 After:
    total: 17 errors, 22 warnings, 1333 lines checked

Signed-off-by: default avatarNick Andrew <nick@nick-andrew.net>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent cd3a1b85

kernel/printk.c

+27 −34
Original line number Diff line number Diff line
@@ -655,13 +655,13 @@ static int acquire_console_semaphore_for_printk(unsigned int cpu) 
static const char recursion_bug_msg [] =

		KERN_CRIT "BUG: recent printk recursion!\n";

static int recursion_bug;

static int log_level_unknown = 1;

	static int new_text_line = 1;

static char printk_buf[1024];



asmlinkage int vprintk(const char *fmt, va_list args)

{

	unsigned long flags;

	int printed_len = 0;

	unsigned long flags;

	int this_cpu;

	char *p;
@@ -703,61 +703,54 @@ asmlinkage int vprintk(const char *fmt, va_list args) 
	printed_len += vscnprintf(printk_buf + printed_len,

				  sizeof(printk_buf) - printed_len, fmt, args);





	/*

	 * Copy the output into log_buf.  If the caller didn't provide

	 * appropriate log level tags, we insert them here

	 */

	for (p = printk_buf; *p; p++) {

		if (log_level_unknown) {

                        /* log_level_unknown signals the start of a new line */

		if (new_text_line) {

			int current_log_level = default_message_loglevel;

			/* If a token, set current_log_level and skip over */

			if (p[0] == '<' && p[1] >= '0' && p[1] <= '7' &&

			    p[2] == '>') {

				current_log_level = p[1] - '0';

				p += 3;

				printed_len -= 3;

			}



			/* Always output the token */

			emit_log_char('<');

			emit_log_char(current_log_level + '0');

			emit_log_char('>');

			printed_len += 3;

			new_text_line = 0;



			if (printk_time) {

				int loglev_char;

				/* Follow the token with the time */

				char tbuf[50], *tp;

				unsigned tlen;

				unsigned long long t;

				unsigned long nanosec_rem;



				/*

				 * force the log level token to be

				 * before the time output.

				 */

				if (p[0] == '<' && p[1] >='0' &&

				   p[1] <= '7' && p[2] == '>') {

					loglev_char = p[1];

					p += 3;

					printed_len -= 3;

				} else {

					loglev_char = default_message_loglevel

						+ '0';

				}

				t = cpu_clock(printk_cpu);

				nanosec_rem = do_div(t, 1000000000);

				tlen = sprintf(tbuf,

						"<%c>[%5lu.%06lu] ",

						loglev_char,

				tlen = sprintf(tbuf, "[%5lu.%06lu] ",

						(unsigned long) t,

						nanosec_rem / 1000);



				for (tp = tbuf; tp < tbuf + tlen; tp++)

					emit_log_char(*tp);

				printed_len += tlen;

			} else {

				if (p[0] != '<' || p[1] < '0' ||

				   p[1] > '7' || p[2] != '>') {

					emit_log_char('<');

					emit_log_char(default_message_loglevel

						+ '0');

					emit_log_char('>');

					printed_len += 3;

			}

			}

			log_level_unknown = 0;



			if (!*p)

				break;

		}



		emit_log_char(*p);

		if (*p == '\n')

			log_level_unknown = 1;

			new_text_line = 1;

	}



	/*

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