#define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)
/* printk's without a loglevel use this.. */
-#define DEFAULT_MESSAGE_LOGLEVEL 4 /* KERN_WARNING */
+#define DEFAULT_MESSAGE_LOGLEVEL CONFIG_DEFAULT_MESSAGE_LOGLEVEL
/* We show everything that is MORE important than this.. */
#define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */
static unsigned con_start; /* Index into log_buf: next char to be sent to consoles */
static unsigned log_end; /* Index into log_buf: most-recently-written-char + 1 */
+/*
+ * If exclusive_console is non-NULL then only this console is to be printed to.
+ */
+static struct console *exclusive_console;
+
/*
* Array of consoles built from command line options (console=)
*/
struct console *con;
for_each_console(con) {
+ if (exclusive_console && con != exclusive_console)
+ continue;
if ((con->flags & CON_ENABLED) && con->write &&
(cpu_online(smp_processor_id()) ||
(con->flags & CON_ANYTIME)))
}
}
+/*
+ * Parse the syslog header <[0-9]*>. The decimal value represents 32bit, the
+ * lower 3 bit are the log level, the rest are the log facility. In case
+ * userspace passes usual userspace syslog messages to /dev/kmsg or
+ * /dev/ttyprintk, the log prefix might contain the facility. Printk needs
+ * to extract the correct log level for in-kernel processing, and not mangle
+ * the original value.
+ *
+ * If a prefix is found, the length of the prefix is returned. If 'level' is
+ * passed, it will be filled in with the log level without a possible facility
+ * value. If 'special' is passed, the special printk prefix chars are accepted
+ * and returned. If no valid header is found, 0 is returned and the passed
+ * variables are not touched.
+ */
+static size_t log_prefix(const char *p, unsigned int *level, char *special)
+{
+ unsigned int lev = 0;
+ char sp = '\0';
+ size_t len;
+
+ if (p[0] != '<' || !p[1])
+ return 0;
+ if (p[2] == '>') {
+ /* usual single digit level number or special char */
+ switch (p[1]) {
+ case '0' ... '7':
+ lev = p[1] - '0';
+ break;
+ case 'c': /* KERN_CONT */
+ case 'd': /* KERN_DEFAULT */
+ sp = p[1];
+ break;
+ default:
+ return 0;
+ }
+ len = 3;
+ } else {
+ /* multi digit including the level and facility number */
+ char *endp = NULL;
+
+ if (p[1] < '0' && p[1] > '9')
+ return 0;
+
+ lev = (simple_strtoul(&p[1], &endp, 10) & 7);
+ if (endp == NULL || endp[0] != '>')
+ return 0;
+ len = (endp + 1) - p;
+ }
+
+ /* do not accept special char if not asked for */
+ if (sp && !special)
+ return 0;
+
+ if (special) {
+ *special = sp;
+ /* return special char, do not touch level */
+ if (sp)
+ return len;
+ }
+
+ if (level)
+ *level = lev;
+ return len;
+}
+
/*
* Call the console drivers, asking them to write out
* log_buf[start] to log_buf[end - 1].
cur_index = start;
start_print = start;
while (cur_index != end) {
- if (msg_level < 0 && ((end - cur_index) > 2) &&
- LOG_BUF(cur_index + 0) == '<' &&
- LOG_BUF(cur_index + 1) >= '0' &&
- LOG_BUF(cur_index + 1) <= '7' &&
- LOG_BUF(cur_index + 2) == '>') {
- msg_level = LOG_BUF(cur_index + 1) - '0';
- cur_index += 3;
+ if (msg_level < 0 && ((end - cur_index) > 2)) {
+ /* strip log prefix */
+ cur_index += log_prefix(&LOG_BUF(cur_index), &msg_level, NULL);
start_print = cur_index;
}
while (cur_index != end) {
unsigned long flags;
int this_cpu;
char *p;
+ size_t plen;
+ char special;
boot_delay_msec();
printk_delay();
printed_len += vscnprintf(printk_buf + printed_len,
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';
- /* Fallthrough - make sure we're on a new line */
- case 'd': /* KERN_DEFAULT */
- if (!new_text_line) {
- emit_log_char('\n');
- new_text_line = 1;
- }
- /* Fallthrough - skip the loglevel */
- case 'c': /* KERN_CONT */
- p += 3;
- break;
+ /* Read log level and handle special printk prefix */
+ plen = log_prefix(p, ¤t_log_level, &special);
+ if (plen) {
+ p += plen;
+
+ switch (special) {
+ case 'c': /* Strip <c> KERN_CONT, continue line */
+ plen = 0;
+ break;
+ case 'd': /* Strip <d> KERN_DEFAULT, start new line */
+ plen = 0;
+ default:
+ if (!new_text_line) {
+ emit_log_char('\n');
+ new_text_line = 1;
}
}
}
/*
- * Copy the output into log_buf. If the caller didn't provide
- * appropriate log level tags, we insert them here
+ * Copy the output into log_buf. If the caller didn't provide
+ * the appropriate log prefix, we insert them here
*/
- for ( ; *p; p++) {
+ for (; *p; p++) {
if (new_text_line) {
- /* 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 (plen) {
+ /* Copy original log prefix */
+ int i;
+
+ for (i = 0; i < plen; i++)
+ emit_log_char(printk_buf[i]);
+ printed_len += plen;
+ } else {
+ /* Add log prefix */
+ emit_log_char('<');
+ emit_log_char(current_log_level + '0');
+ emit_log_char('>');
+ printed_len += 3;
+ }
+
if (printk_time) {
- /* Follow the token with the time */
+ /* Add the current time stamp */
char tbuf[50], *tp;
unsigned tlen;
unsigned long long t;
local_irq_restore(flags);
}
console_locked = 0;
+
+ /* Release the exclusive_console once it is used */
+ if (unlikely(exclusive_console))
+ exclusive_console = NULL;
+
up(&console_sem);
spin_unlock_irqrestore(&logbuf_lock, flags);
if (wake_klogd)
}
EXPORT_SYMBOL(console_start);
+static int __read_mostly keep_bootcon;
+
+static int __init keep_bootcon_setup(char *str)
+{
+ keep_bootcon = 1;
+ printk(KERN_INFO "debug: skip boot console de-registration.\n");
+
+ return 0;
+}
+
+early_param("keep_bootcon", keep_bootcon_setup);
+
/*
* The console driver calls this routine during kernel initialization
* to register the console printing procedure with printk() and to
spin_lock_irqsave(&logbuf_lock, flags);
con_start = log_start;
spin_unlock_irqrestore(&logbuf_lock, flags);
+ /*
+ * We're about to replay the log buffer. Only do this to the
+ * just-registered console to avoid excessive message spam to
+ * the already-registered consoles.
+ */
+ exclusive_console = newcon;
}
console_unlock();
console_sysfs_notify();
* users know there might be something in the kernel's log buffer that
* went to the bootconsole (that they do not see on the real console)
*/
- if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) {
+ if (bcon &&
+ ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV) &&
+ !keep_bootcon) {
/* we need to iterate through twice, to make sure we print
* everything out, before we unregister the console(s)
*/
projects / linux-2.6-microblaze.git / blobdiff