#include <asm/uaccess.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/printk.h>
+
/*
* Architectures can override it:
*/
#define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)
+#ifdef CONFIG_DEBUG_LL
+extern void printascii(char *);
+#endif
+
/* printk's without a loglevel use this.. */
#define DEFAULT_MESSAGE_LOGLEVEL CONFIG_DEFAULT_MESSAGE_LOGLEVEL
}
#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) {
+ 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)
+ spin_unlock_irq(&logbuf_lock);
+
+ return ret;
+}
+
#ifdef CONFIG_SECURITY_DMESG_RESTRICT
int dmesg_restrict = 1;
#else
}
}
-static int __read_mostly ignore_loglevel;
+static bool __read_mostly ignore_loglevel;
static int __init ignore_loglevel_setup(char *str)
{
static void _call_console_drivers(unsigned start,
unsigned end, int msg_log_level)
{
+ trace_console(&LOG_BUF(0), start, end, log_buf_len);
+
if ((msg_log_level < console_loglevel || ignore_loglevel) &&
console_drivers && start != end) {
if ((start & LOG_BUF_MASK) > (end & LOG_BUF_MASK)) {
}
#if defined(CONFIG_PRINTK_TIME)
-static int printk_time = 1;
+static bool printk_time = 1;
#else
-static int printk_time = 0;
+static bool printk_time = 0;
#endif
module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);
+static bool always_kmsg_dump;
+module_param_named(always_kmsg_dump, always_kmsg_dump, bool, S_IRUGO | S_IWUSR);
+
/* Check if we have any console registered that can be called early in boot. */
static int have_callable_console(void)
{
printed_len += vscnprintf(printk_buf + printed_len,
sizeof(printk_buf) - printed_len, fmt, args);
+#ifdef CONFIG_DEBUG_LL
+ printascii(printk_buf);
+#endif
+
p = printk_buf;
/* Read log level and handle special printk prefix */
* Try to acquire and then immediately release the
* console semaphore. The release will do all the
* actual magic (print out buffers, wake up klogd,
- * etc).
+ * etc).
*
* The console_trylock_for_printk() function
* will release 'logbuf_lock' regardless of whether it
return -1;
}
-int console_suspend_enabled = 1;
+bool console_suspend_enabled = 1;
EXPORT_SYMBOL(console_suspend_enabled);
static int __init console_suspend_disable(char *str)
switch (action) {
case CPU_ONLINE:
case CPU_DEAD:
- case CPU_DYING:
case CPU_DOWN_FAILED:
case CPU_UP_CANCELED:
console_lock();
return console_locked;
}
+/*
+ * Delayed printk facility, for scheduler-internal messages:
+ */
+#define PRINTK_BUF_SIZE 512
+
+#define PRINTK_PENDING_WAKEUP 0x01
+#define PRINTK_PENDING_SCHED 0x02
+
static DEFINE_PER_CPU(int, printk_pending);
+static DEFINE_PER_CPU(char [PRINTK_BUF_SIZE], printk_sched_buf);
void printk_tick(void)
{
if (__this_cpu_read(printk_pending)) {
- __this_cpu_write(printk_pending, 0);
- wake_up_interruptible(&log_wait);
+ int pending = __this_cpu_xchg(printk_pending, 0);
+ if (pending & PRINTK_PENDING_SCHED) {
+ char *buf = __get_cpu_var(printk_sched_buf);
+ printk(KERN_WARNING "[sched_delayed] %s", buf);
+ }
+ if (pending & PRINTK_PENDING_WAKEUP)
+ wake_up_interruptible(&log_wait);
}
}
void wake_up_klogd(void)
{
if (waitqueue_active(&log_wait))
- this_cpu_write(printk_pending, 1);
+ this_cpu_or(printk_pending, PRINTK_PENDING_WAKEUP);
}
/**
#if defined CONFIG_PRINTK
+int printk_sched(const char *fmt, ...)
+{
+ unsigned long flags;
+ va_list args;
+ char *buf;
+ int r;
+
+ local_irq_save(flags);
+ buf = __get_cpu_var(printk_sched_buf);
+
+ va_start(args, fmt);
+ r = vsnprintf(buf, PRINTK_BUF_SIZE, fmt, args);
+ va_end(args);
+
+ __this_cpu_or(printk_pending, PRINTK_PENDING_SCHED);
+ local_irq_restore(flags);
+
+ return r;
+}
+
/*
* printk rate limiting, lifted from the networking subsystem.
*
unsigned long l1, l2;
unsigned long flags;
+ if ((reason > KMSG_DUMP_OOPS) && !always_kmsg_dump)
+ return;
+
/* Theoretically, the log could move on after we do this, but
there's not a lot we can do about that. The new messages
will overwrite the start of what we dump. */