#include <asm/uaccess.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/printk.h>
+
/*
* Architectures can override it:
*/
* It is also used in interesting ways to provide interlocking in
* console_unlock();.
*/
-static DEFINE_SPINLOCK(logbuf_lock);
+static DEFINE_RAW_SPINLOCK(logbuf_lock);
#define LOG_BUF_MASK (log_buf_len-1)
#define LOG_BUF(idx) (log_buf[(idx) & LOG_BUF_MASK])
unsigned long mem;
mem = memblock_alloc(new_log_buf_len, PAGE_SIZE);
- if (mem == MEMBLOCK_ERROR)
+ if (!mem)
return;
new_log_buf = __va(mem);
} else {
return;
}
- spin_lock_irqsave(&logbuf_lock, flags);
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
log_buf_len = new_log_buf_len;
log_buf = new_log_buf;
new_log_buf_len = 0;
log_start -= offset;
con_start -= offset;
log_end -= offset;
- spin_unlock_irqrestore(&logbuf_lock, flags);
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
pr_info("log_buf_len: %d\n", log_buf_len);
pr_info("early log buf free: %d(%d%%)\n",
return 0;
/* For historical reasons, accept CAP_SYS_ADMIN too, with a warning */
if (capable(CAP_SYS_ADMIN)) {
- WARN_ONCE(1, "Attempt to access syslog with CAP_SYS_ADMIN "
- "but no CAP_SYSLOG (deprecated).\n");
+ printk_once(KERN_WARNING "%s (%d): "
+ "Attempt to access syslog with CAP_SYS_ADMIN "
+ "but no CAP_SYSLOG (deprecated).\n",
+ current->comm, task_pid_nr(current));
return 0;
}
return -EPERM;
if (error)
goto out;
i = 0;
- spin_lock_irq(&logbuf_lock);
+ raw_spin_lock_irq(&logbuf_lock);
while (!error && (log_start != log_end) && i < len) {
c = LOG_BUF(log_start);
log_start++;
- spin_unlock_irq(&logbuf_lock);
+ raw_spin_unlock_irq(&logbuf_lock);
error = __put_user(c,buf);
buf++;
i++;
cond_resched();
- spin_lock_irq(&logbuf_lock);
+ raw_spin_lock_irq(&logbuf_lock);
}
- spin_unlock_irq(&logbuf_lock);
+ raw_spin_unlock_irq(&logbuf_lock);
if (!error)
error = i;
break;
count = len;
if (count > log_buf_len)
count = log_buf_len;
- spin_lock_irq(&logbuf_lock);
+ raw_spin_lock_irq(&logbuf_lock);
if (count > logged_chars)
count = logged_chars;
if (do_clear)
if (j + log_buf_len < log_end)
break;
c = LOG_BUF(j);
- spin_unlock_irq(&logbuf_lock);
+ raw_spin_unlock_irq(&logbuf_lock);
error = __put_user(c,&buf[count-1-i]);
cond_resched();
- spin_lock_irq(&logbuf_lock);
+ raw_spin_lock_irq(&logbuf_lock);
}
- spin_unlock_irq(&logbuf_lock);
+ raw_spin_unlock_irq(&logbuf_lock);
if (error)
break;
error = i;
}
}
-static int __read_mostly ignore_loglevel;
+static bool __read_mostly ignore_loglevel;
static int __init ignore_loglevel_setup(char *str)
{
}
early_param("ignore_loglevel", ignore_loglevel_setup);
+module_param(ignore_loglevel, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to"
+ "print all kernel messages to the console.");
/*
* Write out chars from start to end - 1 inclusive
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)) {
/* 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;
oops_timestamp = jiffies;
+ debug_locks_off();
/* If a crash is occurring, make sure we can't deadlock */
- spin_lock_init(&logbuf_lock);
+ raw_spin_lock_init(&logbuf_lock);
/* And make sure that we print immediately */
sema_init(&console_sem, 1);
}
#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)
{
}
}
printk_cpu = UINT_MAX;
- spin_unlock(&logbuf_lock);
if (wake)
up(&console_sem);
+ raw_spin_unlock(&logbuf_lock);
return retval;
}
static const char recursion_bug_msg [] =
boot_delay_msec();
printk_delay();
- preempt_disable();
/* This stops the holder of console_sem just where we want him */
- raw_local_irq_save(flags);
+ local_irq_save(flags);
this_cpu = smp_processor_id();
/*
* recursion and return - but flag the recursion so that
* it can be printed at the next appropriate moment:
*/
- if (!oops_in_progress) {
+ if (!oops_in_progress && !lockdep_recursing(current)) {
recursion_bug = 1;
goto out_restore_irqs;
}
}
lockdep_off();
- spin_lock(&logbuf_lock);
+ raw_spin_lock(&logbuf_lock);
printk_cpu = this_cpu;
if (recursion_bug) {
lockdep_on();
out_restore_irqs:
- raw_local_irq_restore(flags);
+ local_irq_restore(flags);
- preempt_enable();
return printed_len;
}
EXPORT_SYMBOL(printk);
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)
return 1;
}
__setup("no_console_suspend", console_suspend_disable);
+module_param_named(console_suspend, console_suspend_enabled,
+ bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(console_suspend, "suspend console during suspend"
+ " and hibernate operations");
/**
* suspend_console - suspend the console subsystem
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);
}
/**
again:
for ( ; ; ) {
- spin_lock_irqsave(&logbuf_lock, flags);
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
wake_klogd |= log_start - log_end;
if (con_start == log_end)
break; /* Nothing to print */
_con_start = con_start;
_log_end = log_end;
con_start = log_end; /* Flush */
- spin_unlock(&logbuf_lock);
+ raw_spin_unlock(&logbuf_lock);
stop_critical_timings(); /* don't trace print latency */
call_console_drivers(_con_start, _log_end);
start_critical_timings();
if (unlikely(exclusive_console))
exclusive_console = NULL;
- spin_unlock(&logbuf_lock);
+ raw_spin_unlock(&logbuf_lock);
up(&console_sem);
* there's a new owner and the console_unlock() from them will do the
* flush, no worries.
*/
- spin_lock(&logbuf_lock);
+ raw_spin_lock(&logbuf_lock);
if (con_start != log_end)
retry = 1;
- spin_unlock_irqrestore(&logbuf_lock, flags);
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+
if (retry && console_trylock())
goto again;
* console_unlock(); will print out the buffered messages
* for us.
*/
- spin_lock_irqsave(&logbuf_lock, flags);
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
con_start = log_start;
- spin_unlock_irqrestore(&logbuf_lock, flags);
+ raw_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
struct console *con;
for_each_console(con) {
- if (con->flags & CON_BOOT) {
+ if (!keep_bootcon && con->flags & CON_BOOT) {
printk(KERN_INFO "turn off boot console %s%d\n",
con->name, con->index);
unregister_console(con);
#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. */
- spin_lock_irqsave(&logbuf_lock, flags);
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
end = log_end & LOG_BUF_MASK;
chars = logged_chars;
- spin_unlock_irqrestore(&logbuf_lock, flags);
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
if (chars > end) {
s1 = log_buf + log_buf_len - chars + end;
projects / linux-flexiantxendom0-3.2.10.git / blobdiff