From 5fd29d6ccbc98884569d6f3105aeca70858b3e0f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 16 Jun 2009 10:57:02 -0700 Subject: [PATCH] printk: clean up handling of log-levels and newlines It used to be that we would only look at the log-level in a printk() after explicit newlines, which can cause annoying problems when the previous printk() did not end with a '\n'. In that case, the log-level marker would be just printed out in the middle of the line, and be seen as just noise rather than change the logging level. This changes things to always look at the log-level in the first bytes of the printout. If a log level marker is found, it is always used as the log-level. Additionally, if no newline existed, one is added (unless the log-level is the explicit KERN_CONT marker, to explicitly show that it's a continuation of a previous line). Acked-by: Arjan van de Ven Signed-off-by: Linus Torvalds --- include/linux/kernel.h | 2 +- kernel/printk.c | 31 ++++++++++++++++++++++--------- 2 files changed, 23 insertions(+), 10 deletions(-) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 883cd44..066bb1e 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -102,7 +102,7 @@ extern const char linux_proc_banner[]; * line that had no enclosing \n). Only to be used by core/arch code * during early bootup (a continued line is not SMP-safe otherwise). */ -#define KERN_CONT "" +#define KERN_CONT "" extern int console_printk[]; diff --git a/kernel/printk.c b/kernel/printk.c index 5052b54..a87770c 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -687,20 +687,33 @@ asmlinkage int vprintk(const char *fmt, va_list args) sizeof(printk_buf) - printed_len, fmt, args); + p = printk_buf; + + /* Do we have a loglevel in the string? */ + if (p[0] == '<') { + unsigned char c = p[1]; + if (c && p[2] == '>') { + switch (c) { + case '0' ... '7': /* loglevel */ + current_log_level = c - '0'; + if (!new_text_line) { + emit_log_char('\n'); + new_text_line = 1; + } + /* Fallthrough - skip the loglevel */ + case 'c': /* KERN_CONT */ + p += 3; + break; + } + } + } + /* * 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++) { + for ( ; *p; p++) { 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; - } - /* Always output the token */ emit_log_char('<'); emit_log_char(current_log_level + '0'); -- 2.7.4