On (21/03/17 00:33), John Ogness wrote:
[..]
> void printk_nmi_direct_enter(void)
> {
> @@ -324,27 +44,8 @@ void printk_nmi_direct_exit(void)
> this_cpu_and(printk_context, ~PRINTK_NMI_DIRECT_CONTEXT_MASK);
> }
>
> -#else
> -
> -static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
> -{
> - return 0;
> -}
> -
> #endif /* CONFIG_PRINTK_NMI */
>
> -/*
> - * Lock-less printk(), to avoid deadlocks should the printk() recurse
> - * into itself. It uses a per-CPU buffer to store the message, just like
> - * NMI.
> - */
> -static __printf(1, 0) int vprintk_safe(const char *fmt, va_list args)
> -{
> - struct printk_safe_seq_buf *s = this_cpu_ptr(&safe_print_seq);
> -
> - return printk_safe_log_store(s, fmt, args);
> -}
> -
> /* Can be preempted by NMI. */
> void __printk_safe_enter(void)
> {
> @@ -369,7 +70,10 @@ __printf(1, 0) int vprintk_func(const char *fmt, va_list
> args)
> * Use the main logbuf even in NMI. But avoid calling console
> * drivers that might have their own locks.
> */
> - if ((this_cpu_read(printk_context) & PRINTK_NMI_DIRECT_CONTEXT_MASK)) {
> + if (this_cpu_read(printk_context) &
> + (PRINTK_NMI_DIRECT_CONTEXT_MASK |
> + PRINTK_NMI_CONTEXT_MASK |
> + PRINTK_SAFE_CONTEXT_MASK)) {
Do we need printk_nmi_direct_enter/exit() and PRINTK_NMI_DIRECT_CONTEXT_MASK?
Seems like all printk_safe() paths are now DIRECT - we store messages to the
prb, but don't call console drivers.
-ss
