Re: [Xenomai-core] [PATCH] avoid deadlock-prone sighand_lock in do_schedule_event

[Philippe Gerum <rpm@xenomai.org>]

Jan Kiszka wrote:
> This has been posted earlier already: Fix deadlocks when debugging
> Xenomai applications via gdb by removing any attempt to acquire
> sighand_lock (while holding rq_lock). This patch also cleans up the now
> unused lock wrapper.
> 
> Unless someone complains, I'm going to merge this later today into trunk
> and 2.4.x.
>

It's already in.

> Jan
> 
> ---
>  include/asm-generic/wrappers.h |    1 -
>  ksrc/nucleus/shadow.c          |    2 --
>  2 files changed, 3 deletions(-)
> 
> Index: b/include/asm-generic/wrappers.h
> ===================================================================
> --- a/include/asm-generic/wrappers.h
> +++ b/include/asm-generic/wrappers.h
> @@ -95,7 +95,6 @@ unsigned long __va_to_kva(unsigned long 
>  #define PF_NOFREEZE 0
>  
>  /* Signals */
> -#define wrap_sighand_lock(p)     ((p)->sigmask_lock)
>  #define wrap_get_sigpending(m,p) sigandsets(m, \
>  					    &(p)->pending.signal, \
>  					    &(p)->pending.signal)
> Index: b/ksrc/nucleus/shadow.c
> ===================================================================
> --- a/ksrc/nucleus/shadow.c
> +++ b/ksrc/nucleus/shadow.c
> @@ -2194,9 +2194,7 @@ static inline void do_schedule_event(str
>  			if (signal_pending(next)) {
>  				sigset_t pending;
>  
> -				spin_lock(&wrap_sighand_lock(next));	/* Already interrupt-safe. */
>  				wrap_get_sigpending(&pending, next);
> -				spin_unlock(&wrap_sighand_lock(next));
>  
>  				if (sigismember(&pending, SIGSTOP) ||
>  				    sigismember(&pending, SIGINT))
> 


-- 
Philippe.