svn commit: r224114 - head/sys/ia64/ia64

[Marcel Moolenaar]

Author: marcel
Date: Sat Jul 16 20:16:49 2011
New Revision: 224114
URL: http://svn.freebsd.org/changeset/base/224114

Log:
  Don't send EOI to the CPU before we handled the interrupt.  This could
  potentially trigger multiple pending interrupts for level-sensitive
  interrupts.  However, the event timer interrupt does need EOI before
  being handled to avoid missing clock events.
  
  These conflicting requirements are handled by having the XIV handler
  inform the dispatch code whether or not it send EOI to the CPU. If not,
  the dispatch code will do it. This allows handlers to send EOI before
  doing potentially long-running activities, while still have a sensible
  default behaviour.

Modified:
  head/sys/ia64/ia64/clock.c
  head/sys/ia64/ia64/interrupt.c

Modified: head/sys/ia64/ia64/clock.c
==============================================================================
--- head/sys/ia64/ia64/clock.c	Sat Jul 16 20:03:23 2011	(r224113)
+++ head/sys/ia64/ia64/clock.c	Sat Jul 16 20:16:49 2011	(r224114)
@@ -91,12 +91,14 @@ ia64_ih_clock(struct thread *td, u_int x
 		ia64_set_itm(itc + load);
 	} else
 		ia64_set_itv((1 << 16) | xiv);
+
+	ia64_set_eoi(0);
 	ia64_srlz_d();
 
 	et = &ia64_clock_et;
 	if (et->et_active)
 		et->et_event_cb(et, et->et_arg);
-	return (0);
+	return (1);
 }
 
 /*

Modified: head/sys/ia64/ia64/interrupt.c
==============================================================================
--- head/sys/ia64/ia64/interrupt.c	Sat Jul 16 20:03:23 2011	(r224113)
+++ head/sys/ia64/ia64/interrupt.c	Sat Jul 16 20:16:49 2011	(r224114)
@@ -320,11 +320,12 @@ ia64_handle_intr(struct trapframe *tf)
 	td->td_intr_frame = tf;
 
 	do {
-		ia64_set_eoi(0);
-		ia64_srlz_d();
 		CTR2(KTR_INTR, "INTR: ITC=%u, XIV=%u",
 		    (u_int)tf->tf_special.ifa, xiv);
-		(ia64_handler[xiv])(td, xiv, tf);
+		if (!(ia64_handler[xiv])(td, xiv, tf)) {
+			ia64_set_eoi(0);
+			ia64_srlz_d();
+		}
 		xiv = ia64_get_ivr();
 		ia64_srlz_d();
 	} while (xiv != 15);