signal: correctly deliver signal to current_process.

It may happen that a process needs to send a signal to itself to
synchronize on an asynchronous event, e.g., an event triggered by an
interrupt.

In such case we must correctly clear the proc->sig_wait mask.

This fix also improves the signal delivery's performance, because we
don't need to check anymore if we need to skip the delivery to
current_process.

NOTE: we can replace this check with an ASSERT(), if proc->sig_wait is
set the current process can't actively deliver a signal to itself
(it's in sleep state waiting for a signal and can't run by definition).

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@3890 38d2e660-2303-0410-9eaa-f027e97ec537

diff --git a/bertos/kern/signal.c b/bertos/kern/signal.c
index 71ccf67ada7dd6090ecc5a1420a7580567dda67d..139e69da0274d4d0c1f3f2331a779a8fe36c9732 100644 (file)
--- a/bertos/kern/signal.c
+++ b/bertos/kern/signal.c
@@ -251,9 +251,6 @@ INLINE void __sig_signal(Process *proc, sigmask_t sigs, bool wakeup)
 {
        cpu_flags_t flags;
 
-       if (UNLIKELY(proc == current_process))
-               return;
-
        IRQ_SAVE_DISABLE(flags);
 
        /* Set the signals */
@@ -262,6 +259,8 @@ INLINE void __sig_signal(Process *proc, sigmask_t sigs, bool wakeup)
        /* Check if process needs to be awoken */
        if (proc->sig_recv & proc->sig_wait)
        {
+               ASSERT(proc != current_process);
+
                proc->sig_wait = 0;
                if (wakeup)
                        proc_wakeup(proc);