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

[Jan Kiszka <jan.kiszka@domain.hid>]

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.

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))

-- 
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