64ca752dcb
There is no need to always call blocking console_lock() in console_cpu_notify(), it's quite possible that console_sem can be locked by other CPU on the system, either already printing or soon to begin printing the messages. console_lock() in this case can simply block CPU hotplug for unknown period of time (console_unlock() is time unbound). Not that hotplug is very fast, but still, with other CPUs being online and doing printk() console_cpu_notify() can stuck. Use console_trylock() instead and opt-out if console_sem is already acquired from another CPU, since that CPU will do the printing for us. Link: http://lkml.kernel.org/r/20170121104729.8585-1-sergey.senozhatsky@gmail.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> |
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| .. | ||
| braille.c | ||
| braille.h | ||
| console_cmdline.h | ||
| internal.h | ||
| Makefile | ||
| printk_safe.c | ||
| printk.c | ||