diff options
Diffstat (limited to 'kernel/printk.c')
-rw-r--r-- | kernel/printk.c | 48 |
1 files changed, 47 insertions, 1 deletions
diff --git a/kernel/printk.c b/kernel/printk.c index 7137480b21f..aa1050a2567 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -295,6 +295,53 @@ static inline void boot_delay_msec(void) } #endif +/* + * Return the number of unread characters in the log buffer. + */ +static int log_buf_get_len(void) +{ + return logged_chars; +} + +/* + * Clears the ring-buffer + */ +void log_buf_clear(void) +{ + logged_chars = 0; +} + +/* + * Copy a range of characters from the log buffer. + */ +int log_buf_copy(char *dest, int idx, int len) +{ + int ret, max; + bool took_lock = false; + + if (!oops_in_progress) { + raw_spin_lock_irq(&logbuf_lock); + took_lock = true; + } + + max = log_buf_get_len(); + if (idx < 0 || idx >= max) { + ret = -1; + } else { + if (len > max - idx) + len = max - idx; + ret = len; + idx += (log_end - max); + while (len-- > 0) + dest[len] = LOG_BUF(idx + len); + } + + if (took_lock) + raw_spin_unlock_irq(&logbuf_lock); + + return ret; +} + #ifdef CONFIG_SECURITY_DMESG_RESTRICT int dmesg_restrict = 1; #else @@ -1168,7 +1215,6 @@ static int __cpuinit console_cpu_notify(struct notifier_block *self, switch (action) { case CPU_ONLINE: case CPU_DEAD: - case CPU_DYING: case CPU_DOWN_FAILED: case CPU_UP_CANCELED: console_lock(); |