Commit the support for removing cpumask_t and replacing it directly with

cpuset_t objects.
That is going to offer the underlying support for a simple bump of
MAXCPU and then support for number of cpus > 32 (as it is today).

Right now, cpumask_t is an int, 32 bits on all our supported architecture.
cpumask_t on the other side is implemented as an array of longs, and
easilly extendible by definition.

The architectures touched by this commit are the following:
- amd64
- i386
- pc98
- arm
- ia64
- XEN

while the others are still missing.
Userland is believed to be fully converted with the changes contained
here.

Some technical notes:
- This commit may be considered an ABI nop for all the architectures
  different from amd64 and ia64 (and sparc64 in the future)
- per-cpu members, which are now converted to cpuset_t, needs to be
  accessed avoiding migration, because the size of cpuset_t should be
  considered unknown
- size of cpuset_t objects is different from kernel and userland (this is
  primirally done in order to leave some more space in userland to cope
  with KBI extensions). If you need to access kernel cpuset_t from the
  userland please refer to example in this patch on how to do that
  correctly (kgdb may be a good source, for example).
- Support for other architectures is going to be added soon
- Only MAXCPU for amd64 is bumped now

The patch has been tested by sbruno and Nicholas Esborn on opteron
4 x 12 pack CPUs. More testing on big SMP is expected to came soon.
pluknet tested the patch with his 8-ways on both amd64 and i386.

Tested by:	pluknet, sbruno, gianni, Nicholas Esborn
Reviewed by:	jeff, jhb, sbruno

1 files changed, 8 insertions, 7 deletions

diff --git a/sys/kern/kern_rmlock.c b/sys/kern/kern_rmlock.c
index 7f2b4e7367be..3214e1b55e2f 100644
--- a/sys/kern/kern_rmlock.c
+++ b/sys/kern/kern_rmlock.c
@@ -263,7 +263,7 @@ _rm_rlock_hard(struct rmlock *rm, struct rm_priotracker *tracker, int trylock)
 	pc = pcpu_find(curcpu);
 
 	/* Check if we just need to do a proper critical_exit. */
-	if (!(pc->pc_cpumask & rm->rm_writecpus)) {
+	if (!CPU_OVERLAP(&pc->pc_cpumask, &rm->rm_writecpus)) {
 		critical_exit();
 		return (1);
 	}
@@ -325,7 +325,7 @@ _rm_rlock_hard(struct rmlock *rm, struct rm_priotracker *tracker, int trylock)
 
 	critical_enter();
 	pc = pcpu_find(curcpu);
-	rm->rm_writecpus &= ~pc->pc_cpumask;
+	CPU_NAND(&rm->rm_writecpus, &pc->pc_cpumask);
 	rm_tracker_add(pc, tracker);
 	sched_pin();
 	critical_exit();
@@ -366,7 +366,8 @@ _rm_rlock(struct rmlock *rm, struct rm_priotracker *tracker, int trylock)
 	 * Fast path to combine two common conditions into a single
 	 * conditional jump.
 	 */
-	if (0 == (td->td_owepreempt | (rm->rm_writecpus & pc->pc_cpumask)))
+	if (0 == (td->td_owepreempt |
+	    CPU_OVERLAP(&rm->rm_writecpus,  &pc->pc_cpumask)))
 		return (1);
 
 	/* We do not have a read token and need to acquire one. */
@@ -429,17 +430,17 @@ _rm_wlock(struct rmlock *rm)
 {
 	struct rm_priotracker *prio;
 	struct turnstile *ts;
-	cpumask_t readcpus;
+	cpuset_t readcpus;
 
 	if (rm->lock_object.lo_flags & RM_SLEEPABLE)
 		sx_xlock(&rm->rm_lock_sx);
 	else
 		mtx_lock(&rm->rm_lock_mtx);
 
-	if (rm->rm_writecpus != all_cpus) {
+	if (CPU_CMP(&rm->rm_writecpus, &all_cpus)) {
 		/* Get all read tokens back */
-
-		readcpus = all_cpus & (all_cpus & ~rm->rm_writecpus);
+		readcpus = all_cpus;
+		CPU_NAND(&readcpus, &rm->rm_writecpus);
 		rm->rm_writecpus = all_cpus;
 
 		/*