[PATCH 1/2] printk: Refactor processing of line severity tokens

From: Nick Andrew
Date: Sun Apr 13 2008 - 07:53:33 EST


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.

Signed-off-by: Nick Andrew <nick@xxxxxxxxxxxxxxx>
---

kernel/printk.c | 63 +++++++++++++++++++++++++------------------------------
1 files changed, 29 insertions(+), 34 deletions(-)


diff --git a/kernel/printk.c b/kernel/printk.c
index c46a20a..bca9359 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -656,11 +656,12 @@ static int printk_recursion_bug;

asmlinkage int vprintk(const char *fmt, va_list args)
{
- static int log_level_unknown = 1;
+ static int new_text_line = 1;
static char printk_buf[1024];

- unsigned long flags;
int printed_len = 0;
+ int current_log_level = default_message_loglevel;
+ unsigned long flags;
int this_cpu;
char *p;

@@ -702,61 +703,55 @@ 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) {
+ /* 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;
+ } else {
+ current_log_level = default_message_loglevel;
+ }
+
+ /* 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,
- (unsigned long)t,
- nanosec_rem/1000);
+ 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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