Support and switch to the ULE scheduler:

o  Implement IPI_PREEMPT,
o  Set td_lock for the thread being switched out,
o  For ULE & SMP, loop while td_lock points to blocked_lock for
   the thread being switched in,
o  Enable ULE by default in GENERIC and SKI,

4 files changed, 18 insertions, 3 deletions

diff --git a/sys/ia64/conf/GENERIC b/sys/ia64/conf/GENERIC
index 8c4a0af..6a4baee 100644
--- a/sys/ia64/conf/GENERIC
+++ b/sys/ia64/conf/GENERIC
@@ -48,7 +48,7 @@ options 	NFSLOCKD	# Network Lock Manager
 options 	NFS_ROOT	# NFS usable as root device
 options 	PROCFS		# Process filesystem (/proc)
 options 	PSEUDOFS	# Pseudo-filesystem framework
-options 	SCHED_4BSD	# 4BSD scheduler
+options 	SCHED_ULE	# ULE scheduler
 options 	SCSI_DELAY=5000	# Delay (in ms) before probing SCSI
 options 	SCTP		# Stream Control Transmission Protocol
 options 	SMP		# Symmetric Multi-Processor support
diff --git a/sys/ia64/conf/SKI b/sys/ia64/conf/SKI
index 6e2a4ba..377ee93 100644
--- a/sys/ia64/conf/SKI
+++ b/sys/ia64/conf/SKI
@@ -35,8 +35,8 @@ options 	KTRACE		# ktrace(1) syscall trace support
 options 	MD_ROOT		# MD usable as root device
 options 	PROCFS		# Process filesystem (/proc)
 options 	PSEUDOFS	# Pseudo-filesystem framework
-options 	SCHED_4BSD	# 4BSD scheduler
-#options 	SCHED_ULE	# ULE scheduler
+#options 	SCHED_4BSD	# 4BSD scheduler
+options 	SCHED_ULE	# ULE scheduler
 options 	SKI		# Include SKI support code
 options 	SOFTUPDATES	# Enable FFS soft updates support
 options 	SYSVMSG		# SYSV-style message queues
diff --git a/sys/ia64/ia64/interrupt.c b/sys/ia64/ia64/interrupt.c
index c3dd83d..15783c9 100644
--- a/sys/ia64/ia64/interrupt.c
+++ b/sys/ia64/ia64/interrupt.c
@@ -47,6 +47,7 @@
 #include <sys/ktr.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
+#include <sys/sched.h>
 #include <sys/smp.h>
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
@@ -241,6 +242,9 @@ interrupt(struct trapframe *tf)
 	} else if (vector == ipi_vector[IPI_TEST]) {
 		CTR1(KTR_SMP, "IPI_TEST, cpuid=%d", PCPU_GET(cpuid));
 		mp_ipi_test++;
+	} else if (vector == ipi_vector[IPI_PREEMPT]) {
+		CTR1(KTR_SMP, "IPI_PREEMPT, cpuid=%d", PCPU_GET(cpuid));
+		sched_preempt(curthread);
 #endif
 	} else {
 		ints[PCPU_GET(cpuid)]++;
diff --git a/sys/ia64/ia64/machdep.c b/sys/ia64/ia64/machdep.c
index 149c704..7ce78b8 100644
--- a/sys/ia64/ia64/machdep.c
+++ b/sys/ia64/ia64/machdep.c
@@ -32,6 +32,7 @@ __FBSDID("$FreeBSD$");
 #include "opt_ddb.h"
 #include "opt_kstack_pages.h"
 #include "opt_msgbuf.h"
+#include "opt_sched.h"
 
 #include <sys/param.h>
 #include <sys/proc.h>
@@ -370,6 +371,12 @@ cpu_switch(struct thread *old, struct thread *new, struct mtx *mtx)
 	if (PCPU_GET(fpcurthread) == old)
 		old->td_frame->tf_special.psr |= IA64_PSR_DFH;
 	if (!savectx(oldpcb)) {
+		old->td_lock = mtx;
+#if defined(SCHED_ULE) && defined(SMP)
+		/* td_lock is volatile */
+		while (new->td_lock == &blocked_lock)
+			;
+#endif
 		newpcb = new->td_pcb;
 		oldpcb->pcb_current_pmap =
 		    pmap_switch(newpcb->pcb_current_pmap);
@@ -890,12 +897,16 @@ DELAY(int n)
 {
 	u_int64_t start, end, now;
 
+	sched_pin();
+
 	start = ia64_get_itc();
 	end = start + (itc_frequency * n) / 1000000;
 	/* printf("DELAY from 0x%lx to 0x%lx\n", start, end); */
 	do {
 		now = ia64_get_itc();
 	} while (now < end || (now > start && end < start));
+
+	sched_unpin();
 }
 
 /*