#include <linux/console.h>
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/moduleparam.h>
#include <linux/interrupt.h> /* For in_interrupt() */
-#include <linux/config.h>
#include <linux/delay.h>
#include <linux/smp.h>
#include <linux/security.h>
#include <linux/bootmem.h>
#include <linux/syscalls.h>
+#include <linux/jiffies.h>
#include <asm/uaccess.h>
DEFAULT_CONSOLE_LOGLEVEL, /* default_console_loglevel */
};
-EXPORT_SYMBOL(console_printk);
-
/*
* Low lever drivers may need that to know if they can schedule in
* their unblank() callback or not. So let's export it.
struct console *con;
for (con = console_drivers; con; con = con->next) {
- if ((con->flags & CON_ENABLED) && con->write)
+ if ((con->flags & CON_ENABLED) && con->write &&
+ (cpu_online(smp_processor_id()) ||
+ (con->flags & CON_ANYTIME)))
con->write(con, &LOG_BUF(start), end - start);
}
}
+static int __read_mostly ignore_loglevel;
+
+static int __init ignore_loglevel_setup(char *str)
+{
+ ignore_loglevel = 1;
+ printk(KERN_INFO "debug: ignoring loglevel setting.\n");
+
+ return 1;
+}
+
+__setup("ignore_loglevel", ignore_loglevel_setup);
+
/*
* Write out chars from start to end - 1 inclusive
*/
static void _call_console_drivers(unsigned long start,
unsigned long end, int msg_log_level)
{
- if (msg_log_level < console_loglevel &&
+ if ((msg_log_level < console_loglevel || ignore_loglevel) &&
console_drivers && start != end) {
if ((start & LOG_BUF_MASK) > (end & LOG_BUF_MASK)) {
/* wrapped write */
#else
static int printk_time = 0;
#endif
+module_param(printk_time, int, S_IRUGO | S_IWUSR);
static int __init printk_time_setup(char *str)
{
return sched_clock();
}
+/* Check if we have any console registered that can be called early in boot. */
+static int have_callable_console(void)
+{
+ struct console *con;
+
+ for (con = console_drivers; con; con = con->next)
+ if (con->flags & CON_ANYTIME)
+ return 1;
+
+ return 0;
+}
+
/**
* printk - print a kernel message
* @fmt: format string
zap_locks();
/* This stops the holder of console_sem just where we want him */
- spin_lock_irqsave(&logbuf_lock, flags);
+ local_irq_save(flags);
+ lockdep_off();
+ spin_lock(&logbuf_lock);
printk_cpu = smp_processor_id();
/* Emit the output into the temporary buffer */
log_level_unknown = 1;
}
- if (!cpu_online(smp_processor_id())) {
+ if (!down_trylock(&console_sem)) {
/*
- * Some console drivers may assume that per-cpu resources have
- * been allocated. So don't allow them to be called by this
- * CPU until it is officially up. We shouldn't be calling into
- * random console drivers on a CPU which doesn't exist yet..
+ * We own the drivers. We can drop the spinlock and
+ * let release_console_sem() print the text, maybe ...
*/
- printk_cpu = UINT_MAX;
- spin_unlock_irqrestore(&logbuf_lock, flags);
- goto out;
- }
- if (!down_trylock(&console_sem)) {
console_locked = 1;
+ printk_cpu = UINT_MAX;
+ spin_unlock(&logbuf_lock);
+
/*
- * We own the drivers. We can drop the spinlock and let
- * release_console_sem() print the text
+ * Console drivers may assume that per-cpu resources have
+ * been allocated. So unless they're explicitly marked as
+ * being able to cope (CON_ANYTIME) don't call them until
+ * this CPU is officially up.
*/
- printk_cpu = UINT_MAX;
- spin_unlock_irqrestore(&logbuf_lock, flags);
- console_may_schedule = 0;
- release_console_sem();
+ if (cpu_online(smp_processor_id()) || have_callable_console()) {
+ console_may_schedule = 0;
+ release_console_sem();
+ } else {
+ /* Release by hand to avoid flushing the buffer. */
+ console_locked = 0;
+ up(&console_sem);
+ }
+ lockdep_on();
+ local_irq_restore(flags);
} else {
/*
* Someone else owns the drivers. We drop the spinlock, which
* console drivers with the output which we just produced.
*/
printk_cpu = UINT_MAX;
- spin_unlock_irqrestore(&logbuf_lock, flags);
+ spin_unlock(&logbuf_lock);
+ lockdep_on();
+ local_irq_restore(flags);
}
-out:
+
preempt_enable();
return printed_len;
}
asmlinkage long sys_syslog(int type, char __user *buf, int len)
{
- return 0;
-}
-
-int do_syslog(int type, char __user *buf, int len)
-{
- return 0;
+ return -ENOSYS;
}
static void call_console_drivers(unsigned long start, unsigned long end)
return 0;
}
+#ifndef CONFIG_DISABLE_CONSOLE_SUSPEND
/**
* suspend_console - suspend the console subsystem
*
*/
void suspend_console(void)
{
+ printk("Suspending console(s)\n");
acquire_console_sem();
console_suspended = 1;
}
console_suspended = 0;
release_console_sem();
}
+#endif /* CONFIG_DISABLE_CONSOLE_SUSPEND */
/**
* acquire_console_sem - lock the console system for exclusive use.
{
return console_locked;
}
-EXPORT_SYMBOL(is_console_locked);
/**
* release_console_sem - unlock the console system
up(&secondary_console_sem);
return;
}
+
+ console_may_schedule = 0;
+
for ( ; ; ) {
spin_lock_irqsave(&logbuf_lock, flags);
wake_klogd |= log_start - log_end;
local_irq_restore(flags);
}
console_locked = 0;
- console_may_schedule = 0;
up(&console_sem);
spin_unlock_irqrestore(&logbuf_lock, flags);
if (wake_klogd && !oops_in_progress && waitqueue_active(&log_wait))
printk_ratelimit_burst);
}
EXPORT_SYMBOL(printk_ratelimit);
+
+/**
+ * printk_timed_ratelimit - caller-controlled printk ratelimiting
+ * @caller_jiffies: pointer to caller's state
+ * @interval_msecs: minimum interval between prints
+ *
+ * printk_timed_ratelimit() returns true if more than @interval_msecs
+ * milliseconds have elapsed since the last time printk_timed_ratelimit()
+ * returned true.
+ */
+bool printk_timed_ratelimit(unsigned long *caller_jiffies,
+ unsigned int interval_msecs)
+{
+ if (*caller_jiffies == 0 || time_after(jiffies, *caller_jiffies)) {
+ *caller_jiffies = jiffies + msecs_to_jiffies(interval_msecs);
+ return true;
+ }
+ return false;
+}
+EXPORT_SYMBOL(printk_timed_ratelimit);
projects / powerpc.git / blobdiff