Fix interrupt handling by extending the critical region so that

preemption doesn't happen until after all pending interrupt have
been services.
While here again, simplify the EOI handling by doing it after we
call the XIV-specific handlers, rather than in each of them. The
original thought was that we may want to do an EOI first and the
actual IPI handling next, but that's mostly a micro-optimization.

4 files changed, 19 insertions, 34 deletions

diff --git a/sys/ia64/ia64/clock.c b/sys/ia64/ia64/clock.c
index 0afbc87..2e7f2d8 100644
--- a/sys/ia64/ia64/clock.c
+++ b/sys/ia64/ia64/clock.c
@@ -90,13 +90,9 @@ ia64_ih_clock(struct thread *td, u_int xiv, struct trapframe *tf)
 	int64_t delta;
 	int count;
 
-	ia64_set_eoi(0);
-
 	PCPU_INC(md.stats.pcs_nclks);
 	intrcnt[INTRCNT_CLOCK]++;
 
-	ia64_srlz_d();
-
 	itc = ia64_get_itc();
 
 	adj = PCPU_GET(md.clockadj);
@@ -120,6 +116,7 @@ ia64_ih_clock(struct thread *td, u_int xiv, struct trapframe *tf)
 		count++;
 	}
 	ia64_set_itm(ia64_get_itc() + ia64_clock_reload - adj);
+	ia64_srlz_d();
 	if (count > 0) {
 		adjust_lost += count - 1;
 		if (delta > (ia64_clock_reload >> 3)) {
@@ -134,7 +131,6 @@ ia64_ih_clock(struct thread *td, u_int xiv, struct trapframe *tf)
 	}
 	PCPU_SET(md.clock, clk);
 	PCPU_SET(md.clockadj, adj);
-	ia64_srlz_d();
 	return (0);
 }
 
@@ -150,7 +146,7 @@ pcpu_initclock(void)
 }
 
 /*
- * Start the real-time and statistics clocks. We use cr.itc and cr.itm
+ * Start the real-time and statistics clocks. We use ar.itc and cr.itm
  * to implement a 1000hz clock.
  */
 void
diff --git a/sys/ia64/ia64/exception.S b/sys/ia64/ia64/exception.S
index 5e186f9..4464a88 100644
--- a/sys/ia64/ia64/exception.S
+++ b/sys/ia64/ia64/exception.S
@@ -1303,7 +1303,7 @@ IVT_END(Break_Instruction)
 
 IVT_ENTRY(External_Interrupt, 0x3000)
 {	.mib
-	mov		r17=cr.ivr	// Put the XIV in the trapframe.
+	mov		r17=ar.itc	// Put the ITC in the trapframe.
 	mov		r16=ip
 	br.sptk		exception_save
 	;;
diff --git a/sys/ia64/ia64/interrupt.c b/sys/ia64/ia64/interrupt.c
index ad8a4e3..3376111 100644
--- a/sys/ia64/ia64/interrupt.c
+++ b/sys/ia64/ia64/interrupt.c
@@ -288,30 +288,32 @@ void
 ia64_handle_intr(struct trapframe *tf)
 {
 	struct thread *td;
-	u_int rfi, xiv;
+	u_int xiv;
 
 	td = curthread;
 	ia64_set_fpsr(IA64_FPSR_DEFAULT);
 	PCPU_INC(cnt.v_intr);
 
-	xiv = tf->tf_special.ifa;
+	xiv = ia64_get_ivr();
+	ia64_srlz_d();
 	if (xiv == 15) {
 		PCPU_INC(md.stats.pcs_nstrays);
 		goto out;
 	}
 
-	while (xiv != 15) {
-		CTR1(KTR_INTR, "INTR: XIV=%u", xiv);
-		critical_enter();
-		rfi = (ia64_handler[xiv])(td, xiv, tf);
-		if (rfi) {
-			critical_exit();
-			return;
-		}
+	critical_enter();
+
+	do {
+		CTR2(KTR_INTR, "INTR: ITC=%u, XIV=%u",
+		    (u_int)tf->tf_special.ifa, xiv);
+		(ia64_handler[xiv])(td, xiv, tf);
+		ia64_set_eoi(0);
+		ia64_srlz_d();
 		xiv = ia64_get_ivr();
-		critical_exit();
 		ia64_srlz_d();
-	}
+	} while (xiv != 15);
+
+	critical_exit();
 
  out:
 	if (TRAPF_USERMODE(tf)) {
@@ -327,10 +329,8 @@ static u_int
 ia64_ih_invalid(struct thread *td, u_int xiv, struct trapframe *tf)
 {
 
-	ia64_set_eoi(0);
-	ia64_srlz_d();
 	panic("invalid XIV: %u", xiv);
-	return (1);
+	return (0);
 }
 
 static u_int
@@ -354,8 +354,7 @@ ia64_ih_irq(struct thread *td, u_int xiv, struct trapframe *tf)
 		ia64_intr_mask((void *)(uintptr_t)xiv);
 		log(LOG_ERR, "stray irq%u\n", i->irq);
 	}
-	ia64_set_eoi(0);
-	ia64_srlz_d();
+
 	return (0);
 }
 
diff --git a/sys/ia64/ia64/mp_machdep.c b/sys/ia64/ia64/mp_machdep.c
index b1d32f7..05a655d 100644
--- a/sys/ia64/ia64/mp_machdep.c
+++ b/sys/ia64/ia64/mp_machdep.c
@@ -90,10 +90,8 @@ static u_int
 ia64_ih_ast(struct thread *td, u_int xiv, struct trapframe *tf)
 {
 
-	ia64_set_eoi(0);
 	PCPU_INC(md.stats.pcs_nasts);
 	CTR1(KTR_SMP, "IPI_AST, cpuid=%d", PCPU_GET(cpuid));
-	ia64_srlz_d();
 	return (0);
 }
 
@@ -101,10 +99,8 @@ static u_int
 ia64_ih_highfp(struct thread *td, u_int xiv, struct trapframe *tf)
 {
 
-	ia64_set_eoi(0);
 	PCPU_INC(md.stats.pcs_nhighfps);
 	ia64_highfp_save_ipi();
-	ia64_srlz_d();
 	return (0);
 }
 
@@ -112,11 +108,9 @@ static u_int
 ia64_ih_preempt(struct thread *td, u_int xiv, struct trapframe *tf)
 {
 
-	ia64_set_eoi(0);
 	PCPU_INC(md.stats.pcs_npreempts);
 	CTR1(KTR_SMP, "IPI_PREEMPT, cpuid=%d", PCPU_GET(cpuid));
 	sched_preempt(curthread);
-	ia64_srlz_d();
 	return (0);
 }
 
@@ -124,11 +118,9 @@ static u_int
 ia64_ih_rndzvs(struct thread *td, u_int xiv, struct trapframe *tf)
 {
 
-	ia64_set_eoi(0);
 	PCPU_INC(md.stats.pcs_nrdvs);
 	CTR1(KTR_SMP, "IPI_RENDEZVOUS, cpuid=%d", PCPU_GET(cpuid));
 	smp_rendezvous_action();
-	ia64_srlz_d();
 	return (0);
 }
 
@@ -137,10 +129,8 @@ ia64_ih_stop(struct thread *td, u_int xiv, struct trapframe *tf)
 {
 	cpumask_t mybit;
 
-	ia64_set_eoi(0);
 	PCPU_INC(md.stats.pcs_nstops);
 	mybit = PCPU_GET(cpumask);
-	ia64_srlz_d();
 
 	savectx(PCPU_PTR(md.pcb));