x86, UV: Clean up uv_tlb.c

SGI UV's uv_tlb.c driver has become rather hard to read, with overly large
functions, non-standard coding style and (way) too long variable, constant
and function names and non-obvious code flow sequences.

This patch improves the readability and maintainability of the driver
significantly, by doing the following strict code cleanups with no side
effects:

 - Split long functions into shorter logical functions.

 - Shortened some variable and structure member names.

 - Added special functions for reads and writes of MMR regs with
   very long names.

 - Added the 'tunables' table to shortened tunables_write().

 - Added the 'stat_description' table to shorten uv_ptc_proc_write().

 - Pass fewer 'stat' arguments where it can be derived from the 'bcp'
   argument.

 - Function definitions consistent on one line, and inline in few (short) cases.

 - Moved some small structures and an atomic inline function to the header file.

 - Moved some local variables to the blocks where they are used.

 - Updated the copyright date.

 - Shortened uv_write_global_mmr64() etc. using some aliasing; no
   line breaks. Renamed many uv_.. functions that are not exported.

 - Aligned structure fields.
    [ note that not all structures are aligned the same way though; I'd like
      to keep the extensive commenting in some of them. ]

 - Shortened some long structure names.

 - Standard pass/fail exit from init_per_cpu()

 - Vertical alignment for mass initializations.

 - More separation between blocks of code.

Tested on a 16-processor Altix UV.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: penberg@kernel.org
Link: http://lkml.kernel.org/r/E1QOw12-0004MN-Lp@eag09.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 748 insertions, 696 deletions

diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
index a9856c09c42..68e467f69fe 100644
--- a/arch/x86/platform/uv/tlb_uv.c
+++ b/arch/x86/platform/uv/tlb_uv.c
@@ -1,7 +1,7 @@
 /*
  *	SGI UltraViolet TLB flush routines.
  *
- *	(c) 2008-2010 Cliff Wickman <cpw@sgi.com>, SGI.
+ *	(c) 2008-2011 Cliff Wickman <cpw@sgi.com>, SGI.
  *
  *	This code is released under the GNU General Public License version 2 or
  *	later.
@@ -35,6 +35,7 @@ static int timeout_base_ns[] = {
 		5242880,
 		167772160
 };
+
 static int timeout_us;
 static int nobau;
 static int baudisabled;
@@ -42,20 +43,70 @@ static spinlock_t disable_lock;
 static cycles_t congested_cycles;
 
 /* tunables: */
-static int max_bau_concurrent = MAX_BAU_CONCURRENT;
-static int max_bau_concurrent_constant = MAX_BAU_CONCURRENT;
-static int plugged_delay = PLUGGED_DELAY;
-static int plugsb4reset = PLUGSB4RESET;
-static int timeoutsb4reset = TIMEOUTSB4RESET;
-static int ipi_reset_limit = IPI_RESET_LIMIT;
-static int complete_threshold = COMPLETE_THRESHOLD;
-static int congested_response_us = CONGESTED_RESPONSE_US;
-static int congested_reps = CONGESTED_REPS;
-static int congested_period = CONGESTED_PERIOD;
+static int max_concurr		= MAX_BAU_CONCURRENT;
+static int max_concurr_const	= MAX_BAU_CONCURRENT;
+static int plugged_delay	= PLUGGED_DELAY;
+static int plugsb4reset		= PLUGSB4RESET;
+static int timeoutsb4reset	= TIMEOUTSB4RESET;
+static int ipi_reset_limit	= IPI_RESET_LIMIT;
+static int complete_threshold	= COMPLETE_THRESHOLD;
+static int congested_respns_us	= CONGESTED_RESPONSE_US;
+static int congested_reps	= CONGESTED_REPS;
+static int congested_period	= CONGESTED_PERIOD;
+
+static struct tunables tunables[] = {
+	{&max_concurr, MAX_BAU_CONCURRENT}, /* must be [0] */
+	{&plugged_delay, PLUGGED_DELAY},
+	{&plugsb4reset, PLUGSB4RESET},
+	{&timeoutsb4reset, TIMEOUTSB4RESET},
+	{&ipi_reset_limit, IPI_RESET_LIMIT},
+	{&complete_threshold, COMPLETE_THRESHOLD},
+	{&congested_respns_us, CONGESTED_RESPONSE_US},
+	{&congested_reps, CONGESTED_REPS},
+	{&congested_period, CONGESTED_PERIOD}
+};
+
 static struct dentry *tunables_dir;
 static struct dentry *tunables_file;
 
-static int __init setup_nobau(char *arg)
+/* these correspond to the statistics printed by ptc_seq_show() */
+static char *stat_description[] = {
+	"sent:     number of shootdown messages sent",
+	"stime:    time spent sending messages",
+	"numuvhubs: number of hubs targeted with shootdown",
+	"numuvhubs16: number times 16 or more hubs targeted",
+	"numuvhubs8: number times 8 or more hubs targeted",
+	"numuvhubs4: number times 4 or more hubs targeted",
+	"numuvhubs2: number times 2 or more hubs targeted",
+	"numuvhubs1: number times 1 hub targeted",
+	"numcpus:  number of cpus targeted with shootdown",
+	"dto:      number of destination timeouts",
+	"retries:  destination timeout retries sent",
+	"rok:   :  destination timeouts successfully retried",
+	"resetp:   ipi-style resource resets for plugs",
+	"resett:   ipi-style resource resets for timeouts",
+	"giveup:   fall-backs to ipi-style shootdowns",
+	"sto:      number of source timeouts",
+	"bz:       number of stay-busy's",
+	"throt:    number times spun in throttle",
+	"swack:   image of UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE",
+	"recv:     shootdown messages received",
+	"rtime:    time spent processing messages",
+	"all:      shootdown all-tlb messages",
+	"one:      shootdown one-tlb messages",
+	"mult:     interrupts that found multiple messages",
+	"none:     interrupts that found no messages",
+	"retry:    number of retry messages processed",
+	"canc:     number messages canceled by retries",
+	"nocan:    number retries that found nothing to cancel",
+	"reset:    number of ipi-style reset requests processed",
+	"rcan:     number messages canceled by reset requests",
+	"disable:  number times use of the BAU was disabled",
+	"enable:   number times use of the BAU was re-enabled"
+};
+
+static int __init
+setup_nobau(char *arg)
 {
 	nobau = 1;
 	return 0;
@@ -63,7 +114,7 @@ static int __init setup_nobau(char *arg)
 early_param("nobau", setup_nobau);
 
 /* base pnode in this partition */
-static int uv_partition_base_pnode __read_mostly;
+static int uv_base_pnode __read_mostly;
 /* position of pnode (which is nasid>>1): */
 static int uv_nshift __read_mostly;
 static unsigned long uv_mmask __read_mostly;
@@ -109,60 +160,52 @@ static int __init uvhub_to_first_apicid(int uvhub)
  * clear of the Timeout bit (as well) will free the resource. No reply will
  * be sent (the hardware will only do one reply per message).
  */
-static inline void uv_reply_to_message(struct msg_desc *mdp,
-				       struct bau_control *bcp)
+static void reply_to_message(struct msg_desc *mdp, struct bau_control *bcp)
 {
 	unsigned long dw;
-	struct bau_payload_queue_entry *msg;
+	struct bau_pq_entry *msg;
 
 	msg = mdp->msg;
 	if (!msg->canceled) {
-		dw = (msg->sw_ack_vector << UV_SW_ACK_NPENDING) |
-						msg->sw_ack_vector;
-		uv_write_local_mmr(
-				UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE_ALIAS, dw);
+		dw = (msg->swack_vec << UV_SW_ACK_NPENDING) | msg->swack_vec;
+		write_mmr_sw_ack(dw);
 	}
 	msg->replied_to = 1;
-	msg->sw_ack_vector = 0;
+	msg->swack_vec = 0;
 }
 
 /*
  * Process the receipt of a RETRY message
  */
-static inline void uv_bau_process_retry_msg(struct msg_desc *mdp,
-					    struct bau_control *bcp)
+static void bau_process_retry_msg(struct msg_desc *mdp,
+					struct bau_control *bcp)
 {
 	int i;
 	int cancel_count = 0;
-	int slot2;
 	unsigned long msg_res;
 	unsigned long mmr = 0;
-	struct bau_payload_queue_entry *msg;
-	struct bau_payload_queue_entry *msg2;
-	struct ptc_stats *stat;
+	struct bau_pq_entry *msg = mdp->msg;
+	struct bau_pq_entry *msg2;
+	struct ptc_stats *stat = bcp->statp;
 
-	msg = mdp->msg;
-	stat = bcp->statp;
 	stat->d_retries++;
 	/*
 	 * cancel any message from msg+1 to the retry itself
 	 */
 	for (msg2 = msg+1, i = 0; i < DEST_Q_SIZE; msg2++, i++) {
-		if (msg2 > mdp->va_queue_last)
-			msg2 = mdp->va_queue_first;
+		if (msg2 > mdp->queue_last)
+			msg2 = mdp->queue_first;
 		if (msg2 == msg)
 			break;
 
-		/* same conditions for cancellation as uv_do_reset */
+		/* same conditions for cancellation as do_reset */
 		if ((msg2->replied_to == 0) && (msg2->canceled == 0) &&
-		    (msg2->sw_ack_vector) && ((msg2->sw_ack_vector &
-			msg->sw_ack_vector) == 0) &&
+		    (msg2->swack_vec) && ((msg2->swack_vec &
+			msg->swack_vec) == 0) &&
 		    (msg2->sending_cpu == msg->sending_cpu) &&
 		    (msg2->msg_type != MSG_NOOP)) {
-			slot2 = msg2 - mdp->va_queue_first;
-			mmr = uv_read_local_mmr
-				(UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE);
-			msg_res = msg2->sw_ack_vector;
+			mmr = read_mmr_sw_ack();
+			msg_res = msg2->swack_vec;
 			/*
 			 * This is a message retry; clear the resources held
 			 * by the previous message only if they timed out.
@@ -170,6 +213,7 @@ static inline void uv_bau_process_retry_msg(struct msg_desc *mdp,
 			 * situation to report.
 			 */
 			if (mmr & (msg_res << UV_SW_ACK_NPENDING)) {
+				unsigned long mr;
 				/*
 				 * is the resource timed out?
 				 * make everyone ignore the cancelled message.
@@ -177,10 +221,8 @@ static inline void uv_bau_process_retry_msg(struct msg_desc *mdp,
 				msg2->canceled = 1;
 				stat->d_canceled++;
 				cancel_count++;
-				uv_write_local_mmr(
-				    UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE_ALIAS,
-					(msg_res << UV_SW_ACK_NPENDING) |
-					 msg_res);
+				mr = (msg_res << UV_SW_ACK_NPENDING) | msg_res;
+				write_mmr_sw_ack(mr);
 			}
 		}
 	}
@@ -192,20 +234,19 @@ static inline void uv_bau_process_retry_msg(struct msg_desc *mdp,
  * Do all the things a cpu should do for a TLB shootdown message.
  * Other cpu's may come here at the same time for this message.
  */
-static void uv_bau_process_message(struct msg_desc *mdp,
-				   struct bau_control *bcp)
+static void bau_process_message(struct msg_desc *mdp,
+					struct bau_control *bcp)
 {
-	int msg_ack_count;
 	short socket_ack_count = 0;
-	struct ptc_stats *stat;
-	struct bau_payload_queue_entry *msg;
+	short *sp;
+	struct atomic_short *asp;
+	struct ptc_stats *stat = bcp->statp;
+	struct bau_pq_entry *msg = mdp->msg;
 	struct bau_control *smaster = bcp->socket_master;
 
 	/*
 	 * This must be a normal message, or retry of a normal message
 	 */
-	msg = mdp->msg;
-	stat = bcp->statp;
 	if (msg->address == TLB_FLUSH_ALL) {
 		local_flush_tlb();
 		stat->d_alltlb++;
@@ -222,30 +263,32 @@ static void uv_bau_process_message(struct msg_desc *mdp,
 	 * cpu number.
 	 */
 	if (msg->msg_type == MSG_RETRY && bcp == bcp->uvhub_master)
-		uv_bau_process_retry_msg(mdp, bcp);
+		bau_process_retry_msg(mdp, bcp);
 
 	/*
-	 * This is a sw_ack message, so we have to reply to it.
+	 * This is a swack message, so we have to reply to it.
 	 * Count each responding cpu on the socket. This avoids
 	 * pinging the count's cache line back and forth between
 	 * the sockets.
 	 */
-	socket_ack_count = atomic_add_short_return(1, (struct atomic_short *)
-			&smaster->socket_acknowledge_count[mdp->msg_slot]);
+	sp = &smaster->socket_acknowledge_count[mdp->msg_slot];
+	asp = (struct atomic_short *)sp;
+	socket_ack_count = atom_asr(1, asp);
 	if (socket_ack_count == bcp->cpus_in_socket) {
+		int msg_ack_count;
 		/*
 		 * Both sockets dump their completed count total into
 		 * the message's count.
 		 */
 		smaster->socket_acknowledge_count[mdp->msg_slot] = 0;
-		msg_ack_count = atomic_add_short_return(socket_ack_count,
-				(struct atomic_short *)&msg->acknowledge_count);
+		asp = (struct atomic_short *)&msg->acknowledge_count;
+		msg_ack_count = atom_asr(socket_ack_count, asp);
 
 		if (msg_ack_count == bcp->cpus_in_uvhub) {
 			/*
 			 * All cpus in uvhub saw it; reply
 			 */
-			uv_reply_to_message(mdp, bcp);
+			reply_to_message(mdp, bcp);
 		}
 	}
 
@@ -268,62 +311,51 @@ static int uvhub_to_first_cpu(int uvhub)
  * Last resort when we get a large number of destination timeouts is
  * to clear resources held by a given cpu.
  * Do this with IPI so that all messages in the BAU message queue
- * can be identified by their nonzero sw_ack_vector field.
+ * can be identified by their nonzero swack_vec field.
  *
  * This is entered for a single cpu on the uvhub.
  * The sender want's this uvhub to free a specific message's
- * sw_ack resources.
+ * swack resources.
  */
-static void
-uv_do_reset(void *ptr)
+static void do_reset(void *ptr)
 {
 	int i;
-	int slot;
-	int count = 0;
-	unsigned long mmr;
-	unsigned long msg_res;
-	struct bau_control *bcp;
-	struct reset_args *rap;
-	struct bau_payload_queue_entry *msg;
-	struct ptc_stats *stat;
+	struct bau_control *bcp = &per_cpu(bau_control, smp_processor_id());
+	struct reset_args *rap = (struct reset_args *)ptr;
+	struct bau_pq_entry *msg;
+	struct ptc_stats *stat = bcp->statp;
 
-	bcp = &per_cpu(bau_control, smp_processor_id());
-	rap = (struct reset_args *)ptr;
-	stat = bcp->statp;
 	stat->d_resets++;
-
 	/*
 	 * We're looking for the given sender, and
-	 * will free its sw_ack resource.
+	 * will free its swack resource.
 	 * If all cpu's finally responded after the timeout, its
 	 * message 'replied_to' was set.
 	 */
-	for (msg = bcp->va_queue_first, i = 0; i < DEST_Q_SIZE; msg++, i++) {
-		/* uv_do_reset: same conditions for cancellation as
-		   uv_bau_process_retry_msg() */
+	for (msg = bcp->queue_first, i = 0; i < DEST_Q_SIZE; msg++, i++) {
+		unsigned long msg_res;
+		/* do_reset: same conditions for cancellation as
+		   bau_process_retry_msg() */
 		if ((msg->replied_to == 0) &&
 		    (msg->canceled == 0) &&
 		    (msg->sending_cpu == rap->sender) &&
-		    (msg->sw_ack_vector) &&
+		    (msg->swack_vec) &&
 		    (msg->msg_type != MSG_NOOP)) {
+			unsigned long mmr;
+			unsigned long mr;
 			/*
 			 * make everyone else ignore this message
 			 */
 			msg->canceled = 1;
-			slot = msg - bcp->va_queue_first;
-			count++;
 			/*
 			 * only reset the resource if it is still pending
 			 */
-			mmr = uv_read_local_mmr
-					(UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE);
-			msg_res = msg->sw_ack_vector;
+			mmr = read_mmr_sw_ack();
+			msg_res = msg->swack_vec;
+			mr = (msg_res << UV_SW_ACK_NPENDING) | msg_res;
 			if (mmr & msg_res) {
 				stat->d_rcanceled++;
-				uv_write_local_mmr(
-				    UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE_ALIAS,
-					(msg_res << UV_SW_ACK_NPENDING) |
-					 msg_res);
+				write_mmr_sw_ack(mr);
 			}
 		}
 	}
@@ -334,39 +366,38 @@ uv_do_reset(void *ptr)
  * Use IPI to get all target uvhubs to release resources held by
  * a given sending cpu number.
  */
-static void uv_reset_with_ipi(struct bau_target_uvhubmask *distribution,
-			      int sender)
+static void reset_with_ipi(struct bau_targ_hubmask *distribution, int sender)
 {
 	int uvhub;
-	int cpu;
+	int maskbits;
 	cpumask_t mask;
 	struct reset_args reset_args;
 
 	reset_args.sender = sender;
-
 	cpus_clear(mask);
 	/* find a single cpu for each uvhub in this distribution mask */
-	for (uvhub = 0;
-		    uvhub < sizeof(struct bau_target_uvhubmask) * BITSPERBYTE;
-		    uvhub++) {
+	maskbits = sizeof(struct bau_targ_hubmask) * BITSPERBYTE;
+	for (uvhub = 0; uvhub < maskbits; uvhub++) {
+		int cpu;
 		if (!bau_uvhub_isset(uvhub, distribution))
 			continue;
 		/* find a cpu for this uvhub */
 		cpu = uvhub_to_first_cpu(uvhub);
 		cpu_set(cpu, mask);
 	}
-	/* IPI all cpus; Preemption is already disabled */
-	smp_call_function_many(&mask, uv_do_reset, (void *)&reset_args, 1);
+
+	/* IPI all cpus; preemption is already disabled */
+	smp_call_function_many(&mask, do_reset, (void *)&reset_args, 1);
 	return;
 }
 
-static inline unsigned long
-cycles_2_us(unsigned long long cyc)
+static inline unsigned long cycles_2_us(unsigned long long cyc)
 {
 	unsigned long long ns;
 	unsigned long us;
-	ns =  (cyc * per_cpu(cyc2ns, smp_processor_id()))
-						>> CYC2NS_SCALE_FACTOR;
+	int cpu = smp_processor_id();
+
+	ns =  (cyc * per_cpu(cyc2ns, cpu)) >> CYC2NS_SCALE_FACTOR;
 	us = ns / 1000;
 	return us;
 }
@@ -376,21 +407,27 @@ cycles_2_us(unsigned long long cyc)
  * leaves uvhub_quiesce set so that no new broadcasts are started by
  * bau_flush_send_and_wait()
  */
-static inline void
-quiesce_local_uvhub(struct bau_control *hmaster)
+static inline void quiesce_local_uvhub(struct bau_control *hmaster)
 {
-	atomic_add_short_return(1, (struct atomic_short *)
-		 &hmaster->uvhub_quiesce);
+	atom_asr(1, (struct atomic_short *)&hmaster->uvhub_quiesce);
 }
 
 /*
  * mark this quiet-requestor as done
  */
-static inline void
-end_uvhub_quiesce(struct bau_control *hmaster)
+static inline void end_uvhub_quiesce(struct bau_control *hmaster)
 {
-	atomic_add_short_return(-1, (struct atomic_short *)
-		&hmaster->uvhub_quiesce);
+	atom_asr(-1, (struct atomic_short *)&hmaster->uvhub_quiesce);
+}
+
+static unsigned long uv1_read_status(unsigned long mmr_offset, int right_shift)
+{
+	unsigned long descriptor_status;
+
+	descriptor_status = uv_read_local_mmr(mmr_offset);
+	descriptor_status >>= right_shift;
+	descriptor_status &= UV_ACT_STATUS_MASK;
+	return descriptor_status;
 }
 
 /*
@@ -398,31 +435,28 @@ end_uvhub_quiesce(struct bau_control *hmaster)
  * return COMPLETE, RETRY(PLUGGED or TIMEOUT) or GIVEUP
  */
 static int uv1_wait_completion(struct bau_desc *bau_desc,
-	unsigned long mmr_offset, int right_shift, int this_cpu,
-	struct bau_control *bcp, struct bau_control *smaster, long try)
+				unsigned long mmr_offset, int right_shift,
+				struct bau_control *bcp, long try)
 {
 	unsigned long descriptor_status;
-	cycles_t ttime;
+	cycles_t ttm;
 	struct ptc_stats *stat = bcp->statp;
 
+	descriptor_status = uv1_read_status(mmr_offset, right_shift);
 	/* spin on the status MMR, waiting for it to go idle */
-	while ((descriptor_status = (((unsigned long)
-		uv_read_local_mmr(mmr_offset) >>
-			right_shift) & UV_ACT_STATUS_MASK)) !=
-			DESC_STATUS_IDLE) {
+	while ((descriptor_status != DS_IDLE)) {
 		/*
 		 * Our software ack messages may be blocked because
 		 * there are no swack resources available.  As long
 		 * as none of them has timed out hardware will NACK
 		 * our message and its state will stay IDLE.
 		 */
-		if (descriptor_status == DESC_STATUS_SOURCE_TIMEOUT) {
+		if (descriptor_status == DS_SOURCE_TIMEOUT) {
 			stat->s_stimeout++;
 			return FLUSH_GIVEUP;
-		} else if (descriptor_status ==
-				DESC_STATUS_DESTINATION_TIMEOUT) {
+		} else if (descriptor_status == DS_DESTINATION_TIMEOUT) {
 			stat->s_dtimeout++;
-			ttime = get_cycles();
+			ttm = get_cycles();
 
 			/*
 			 * Our retries may be blocked by all destination
@@ -430,8 +464,7 @@ static int uv1_wait_completion(struct bau_desc *bau_desc,
 			 * pending.  In that case hardware returns the
 			 * ERROR that looks like a destination timeout.
 			 */
-			if (cycles_2_us(ttime - bcp->send_message) <
-							timeout_us) {
+			if (cycles_2_us(ttm - bcp->send_message) < timeout_us) {
 				bcp->conseccompletes = 0;
 				return FLUSH_RETRY_PLUGGED;
 			}
@@ -444,93 +477,106 @@ static int uv1_wait_completion(struct bau_desc *bau_desc,
 			 */
 			cpu_relax();
 		}
+		descriptor_status = uv1_read_status(mmr_offset, right_shift);
 	}
 	bcp->conseccompletes++;
 	return FLUSH_COMPLETE;
 }
 
-static int uv2_wait_completion(struct bau_desc *bau_desc,
-	unsigned long mmr_offset, int right_shift, int this_cpu,
-	struct bau_control *bcp, struct bau_control *smaster, long try)
+/*
+ * UV2 has an extra bit of status in the ACTIVATION_STATUS_2 register.
+ */
+static unsigned long uv2_read_status(unsigned long offset, int rshft, int cpu)
 {
 	unsigned long descriptor_status;
 	unsigned long descriptor_status2;
-	int cpu;
-	cycles_t ttime;
+
+	descriptor_status = ((read_lmmr(offset) >> rshft) & UV_ACT_STATUS_MASK);
+	descriptor_status2 = (read_mmr_uv2_status() >> cpu) & 0x1UL;
+	descriptor_status = (descriptor_status << 1) | descriptor_status2;
+	return descriptor_status;
+}
+
+static int uv2_wait_completion(struct bau_desc *bau_desc,
+				unsigned long mmr_offset, int right_shift,
+				struct bau_control *bcp, long try)
+{
+	unsigned long descriptor_stat;
+	cycles_t ttm;
+	int cpu = bcp->uvhub_cpu;
 	struct ptc_stats *stat = bcp->statp;
 
-	/* UV2 has an extra bit of status */
-	cpu = bcp->uvhub_cpu;
+	descriptor_stat = uv2_read_status(mmr_offset, right_shift, cpu);
+
 	/* spin on the status MMR, waiting for it to go idle */
-	descriptor_status = (((unsigned long)(uv_read_local_mmr
-		(mmr_offset)) >> right_shift) & UV_ACT_STATUS_MASK);
-	descriptor_status2 = (((unsigned long)uv_read_local_mmr
-		(UV2H_LB_BAU_SB_ACTIVATION_STATUS_2) >> cpu) & 0x1UL);
-	descriptor_status = (descriptor_status << 1) |
-		descriptor_status2;
-	while (descriptor_status != UV2H_DESC_IDLE) {
+	while (descriptor_stat != UV2H_DESC_IDLE) {
 		/*
 		 * Our software ack messages may be blocked because
 		 * there are no swack resources available.  As long
 		 * as none of them has timed out hardware will NACK
 		 * our message and its state will stay IDLE.
 		 */
-		if ((descriptor_status == UV2H_DESC_SOURCE_TIMEOUT) ||
-		    (descriptor_status == UV2H_DESC_DEST_STRONG_NACK) ||
-		    (descriptor_status == UV2H_DESC_DEST_PUT_ERR)) {
+		if ((descriptor_stat == UV2H_DESC_SOURCE_TIMEOUT) ||
+		    (descriptor_stat == UV2H_DESC_DEST_STRONG_NACK) ||
+		    (descriptor_stat == UV2H_DESC_DEST_PUT_ERR)) {
 			stat->s_stimeout++;
 			return FLUSH_GIVEUP;
-		} else if (descriptor_status == UV2H_DESC_DEST_TIMEOUT) {
+		} else if (descriptor_stat == UV2H_DESC_DEST_TIMEOUT) {
 			stat->s_dtimeout++;
-			ttime = get_cycles();
-
+			ttm = get_cycles();
 			/*
 			 * Our retries may be blocked by all destination
 			 * swack resources being consumed, and a timeout
 			 * pending.  In that case hardware returns the
 			 * ERROR that looks like a destination timeout.
 			 */
-			if (cycles_2_us(ttime - bcp->send_message) <
-							timeout_us) {
+			if (cycles_2_us(ttm - bcp->send_message) < timeout_us) {
 				bcp->conseccompletes = 0;
 				return FLUSH_RETRY_PLUGGED;
 			}
-
 			bcp->conseccompletes = 0;
 			return FLUSH_RETRY_TIMEOUT;
 		} else {
 			/*
-			 * descriptor_status is still BUSY
+			 * descriptor_stat is still BUSY
 			 */
 			cpu_relax();
 		}
-		descriptor_status = (((unsigned long)(uv_read_local_mmr
-			(mmr_offset)) >> right_shift) &
-			UV_ACT_STATUS_MASK);
-		descriptor_status2 = (((unsigned long)uv_read_local_mmr
-			(UV2H_LB_BAU_SB_ACTIVATION_STATUS_2) >> cpu) &
-			0x1UL);
-		descriptor_status = (descriptor_status << 1) |
-			descriptor_status2;
+		descriptor_stat = uv2_read_status(mmr_offset, right_shift, cpu);
 	}
 	bcp->conseccompletes++;
 	return FLUSH_COMPLETE;
 }
 
-static int uv_wait_completion(struct bau_desc *bau_desc,
-	unsigned long mmr_offset, int right_shift, int this_cpu,
-	struct bau_control *bcp, struct bau_control *smaster, long try)
+/*
+ * There are 2 status registers; each and array[32] of 2 bits. Set up for
+ * which register to read and position in that register based on cpu in
+ * current hub.
+ */
+static int wait_completion(struct bau_desc *bau_desc,
+				struct bau_control *bcp, long try)
 {
+	int right_shift;
+	unsigned long mmr_offset;
+	int cpu = bcp->uvhub_cpu;
+
+	if (cpu < UV_CPUS_PER_AS) {
+		mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_0;
+		right_shift = cpu * UV_ACT_STATUS_SIZE;
+	} else {
+		mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_1;
+		right_shift = ((cpu - UV_CPUS_PER_AS) * UV_ACT_STATUS_SIZE);
+	}
+
 	if (is_uv1_hub())
 		return uv1_wait_completion(bau_desc, mmr_offset, right_shift,
-				   this_cpu, bcp, smaster, try);
+								bcp, try);
 	else
 		return uv2_wait_completion(bau_desc, mmr_offset, right_shift,
-				   this_cpu, bcp, smaster, try);
+								bcp, try);
 }
 
-static inline cycles_t
-sec_2_cycles(unsigned long sec)
+static inline cycles_t sec_2_cycles(unsigned long sec)
 {
 	unsigned long ns;
 	cycles_t cyc;
@@ -541,63 +587,50 @@ sec_2_cycles(unsigned long sec)
 }
 
 /*
- * conditionally add 1 to *v, unless *v is >= u
- * return 0 if we cannot add 1 to *v because it is >= u
- * return 1 if we can add 1 to *v because it is < u
- * the add is atomic
- *
- * This is close to atomic_add_unless(), but this allows the 'u' value
- * to be lowered below the current 'v'.  atomic_add_unless can only stop
- * on equal.
- */
-static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u)
-{
-	spin_lock(lock);
-	if (atomic_read(v) >= u) {
-		spin_unlock(lock);
-		return 0;
-	}
-	atomic_inc(v);
-	spin_unlock(lock);
-	return 1;
-}
-
-/*
- * Our retries are blocked by all destination swack resources being
+ * Our retries are blocked by all destination sw ack resources being
  * in use, and a timeout is pending. In that case hardware immediately
  * returns the ERROR that looks like a destination timeout.
  */
-static void
-destination_plugged(struct bau_desc *bau_desc, struct bau_control *bcp,
+static void destination_plugged(struct bau_desc *bau_desc,
+			struct bau_control *bcp,
 			struct bau_control *hmaster, struct ptc_stats *stat)
 {
 	udelay(bcp->plugged_delay);
 	bcp->plugged_tries++;
+
 	if (bcp->plugged_tries >= bcp->plugsb4reset) {
 		bcp->plugged_tries = 0;
+
 		quiesce_local_uvhub(hmaster);
+
 		spin_lock(&hmaster->queue_lock);
-		uv_reset_with_ipi(&bau_desc->distribution, bcp->cpu);
+		reset_with_ipi(&bau_desc->distribution, bcp->cpu);
 		spin_unlock(&hmaster->queue_lock);
+
 		end_uvhub_quiesce(hmaster);
+
 		bcp->ipi_attempts++;
 		stat->s_resets_plug++;
 	}
 }
 
-static void
-destination_timeout(struct bau_desc *bau_desc, struct bau_control *bcp,
-			struct bau_control *hmaster, struct ptc_stats *stat)
+static void destination_timeout(struct bau_desc *bau_desc,
+			struct bau_control *bcp, struct bau_control *hmaster,
+			struct ptc_stats *stat)
 {
-	hmaster->max_bau_concurrent = 1;
+	hmaster->max_concurr = 1;
 	bcp->timeout_tries++;
 	if (bcp->timeout_tries >= bcp->timeoutsb4reset) {
 		bcp->timeout_tries = 0;
+
 		quiesce_local_uvhub(hmaster);
+
 		spin_lock(&hmaster->queue_lock);
-		uv_reset_with_ipi(&bau_desc->distribution, bcp->cpu);
+		reset_with_ipi(&bau_desc->distribution, bcp->cpu);
 		spin_unlock(&hmaster->queue_lock);
+
 		end_uvhub_quiesce(hmaster);
+
 		bcp->ipi_attempts++;
 		stat->s_resets_timeout++;
 	}
@@ -607,34 +640,104 @@ destination_timeout(struct bau_desc *bau_desc, struct bau_control *bcp,
  * Completions are taking a very long time due to a congested numalink
  * network.
  */
-static void
-disable_for_congestion(struct bau_control *bcp, struct ptc_stats *stat)
+static void disable_for_congestion(struct bau_control *bcp,
+					struct ptc_stats *stat)
 {
-	int tcpu;
-	struct bau_control *tbcp;
-
 	/* let only one cpu do this disabling */
 	spin_lock(&disable_lock);
+
 	if (!baudisabled && bcp->period_requests &&
 	    ((bcp->period_time / bcp->period_requests) > congested_cycles)) {
+		int tcpu;
+		struct bau_control *tbcp;
 		/* it becomes this cpu's job to turn on the use of the
 		   BAU again */
 		baudisabled = 1;
 		bcp->set_bau_off = 1;
-		bcp->set_bau_on_time = get_cycles() +
-			sec_2_cycles(bcp->congested_period);
+		bcp->set_bau_on_time = get_cycles();
+		bcp->set_bau_on_time += sec_2_cycles(bcp->cong_period);
 		stat->s_bau_disabled++;
 		for_each_present_cpu(tcpu) {
 			tbcp = &per_cpu(bau_control, tcpu);
-				tbcp->baudisabled = 1;
+			tbcp->baudisabled = 1;
 		}
 	}
+
 	spin_unlock(&disable_lock);
 }
 
-/**
- * uv_flush_send_and_wait
- *
+static void count_max_concurr(int stat, struct bau_control *bcp,
+				struct bau_control *hmaster)
+{
+	bcp->plugged_tries = 0;
+	bcp->timeout_tries = 0;
+	if (stat != FLUSH_COMPLETE)
+		return;
+	if (bcp->conseccompletes <= bcp->complete_threshold)
+		return;
+	if (hmaster->max_concurr >= hmaster->max_concurr_const)
+		return;
+	hmaster->max_concurr++;
+}
+
+static void record_send_stats(cycles_t time1, cycles_t time2,
+		struct bau_control *bcp, struct ptc_stats *stat,
+		int completion_status, int try)
+{
+	cycles_t elapsed;
+
+	if (time2 > time1) {
+		elapsed = time2 - time1;
+		stat->s_time += elapsed;
+
+		if ((completion_status == FLUSH_COMPLETE) && (try == 1)) {
+			bcp->period_requests++;
+			bcp->period_time += elapsed;
+			if ((elapsed > congested_cycles) &&
+			    (bcp->period_requests > bcp->cong_reps))
+				disable_for_congestion(bcp, stat);
+		}
+	} else
+		stat->s_requestor--;
+
+	if (completion_status == FLUSH_COMPLETE && try > 1)
+		stat->s_retriesok++;
+	else if (completion_status == FLUSH_GIVEUP)
+		stat->s_giveup++;
+}
+
+/*
+ * Because of a uv1 hardware bug only a limited number of concurrent
+ * requests can be made.
+ */
+static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat)
+{
+	spinlock_t *lock = &hmaster->uvhub_lock;
+	atomic_t *v;
+
+	v = &hmaster->active_descriptor_count;
+	if (!atomic_inc_unless_ge(lock, v, hmaster->max_concurr)) {
+		stat->s_throttles++;
+		do {
+			cpu_relax();
+		} while (!atomic_inc_unless_ge(lock, v, hmaster->max_concurr));
+	}
+}
+
+/*
+ * Handle the completion status of a message send.
+ */
+static void handle_cmplt(int completion_status, struct bau_desc *bau_desc,
+			struct bau_control *bcp, struct bau_control *hmaster,
+			struct ptc_stats *stat)
+{
+	if (completion_status == FLUSH_RETRY_PLUGGED)
+		destination_plugged(bau_desc, bcp, hmaster, stat);
+	else if (completion_status == FLUSH_RETRY_TIMEOUT)
+		destination_timeout(bau_desc, bcp, hmaster, stat);
+}
+
+/*
  * Send a broadcast and wait for it to complete.
  *
  * The flush_mask contains the cpus the broadcast is to be sent to including
@@ -645,45 +748,23 @@ disable_for_congestion(struct bau_control *bcp, struct ptc_stats *stat)
  * returned to the kernel.
  */
 int uv_flush_send_and_wait(struct bau_desc *bau_desc,
-			   struct cpumask *flush_mask, struct bau_control *bcp)
+			struct cpumask *flush_mask, struct bau_control *bcp)
 {
-	int right_shift;
-	int completion_status = 0;
 	int seq_number = 0;
+	int completion_stat = 0;
 	long try = 0;
-	int cpu = bcp->uvhub_cpu;
-	int this_cpu = bcp->cpu;
-	unsigned long mmr_offset;
 	unsigned long index;
 	cycles_t time1;
 	cycles_t time2;
-	cycles_t elapsed;
 	struct ptc_stats *stat = bcp->statp;
-	struct bau_control *smaster = bcp->socket_master;
 	struct bau_control *hmaster = bcp->uvhub_master;
 
-	if (is_uv1_hub()  &&
-			!atomic_inc_unless_ge(&hmaster->uvhub_lock,
-			&hmaster->active_descriptor_count,
-			hmaster->max_bau_concurrent)) {
-		stat->s_throttles++;
-		do {
-			cpu_relax();
-		} while (!atomic_inc_unless_ge(&hmaster->uvhub_lock,
-			&hmaster->active_descriptor_count,
-			hmaster->max_bau_concurrent));
-	}
+	if (is_uv1_hub())
+		uv1_throttle(hmaster, stat);
+
 	while (hmaster->uvhub_quiesce)
 		cpu_relax();
 
-	if (cpu < UV_CPUS_PER_ACT_STATUS) {
-		mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_0;
-		right_shift = cpu * UV_ACT_STATUS_SIZE;
-	} else {
-		mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_1;
-		right_shift =
-		    ((cpu - UV_CPUS_PER_ACT_STATUS) * UV_ACT_STATUS_SIZE);
-	}
 	time1 = get_cycles();
 	do {
 		if (try == 0) {
@@ -693,64 +774,134 @@ int uv_flush_send_and_wait(struct bau_desc *bau_desc,
 			bau_desc->header.msg_type = MSG_RETRY;
 			stat->s_retry_messages++;
 		}
+
 		bau_desc->header.sequence = seq_number;
-		index = (1UL << UVH_LB_BAU_SB_ACTIVATION_CONTROL_PUSH_SHFT) |
-			bcp->uvhub_cpu;
+		index = (1UL << AS_PUSH_SHIFT) | bcp->uvhub_cpu;
 		bcp->send_message = get_cycles();
-		uv_write_local_mmr(UVH_LB_BAU_SB_ACTIVATION_CONTROL, index);
+
+		write_mmr_activation(index);
+
 		try++;
-		completion_status = uv_wait_completion(bau_desc, mmr_offset,
-			right_shift, this_cpu, bcp, smaster, try);
+		completion_stat = wait_completion(bau_desc, bcp, try);
+
+		handle_cmplt(completion_stat, bau_desc, bcp, hmaster, stat);
 
-		if (completion_status == FLUSH_RETRY_PLUGGED) {
-			destination_plugged(bau_desc, bcp, hmaster, stat);
-		} else if (completion_status == FLUSH_RETRY_TIMEOUT) {
-			destination_timeout(bau_desc, bcp, hmaster, stat);
-		}
 		if (bcp->ipi_attempts >= bcp->ipi_reset_limit) {
 			bcp->ipi_attempts = 0;
-			completion_status = FLUSH_GIVEUP;
+			completion_stat = FLUSH_GIVEUP;
 			break;
 		}
 		cpu_relax();
-	} while ((completion_status == FLUSH_RETRY_PLUGGED) ||
-		 (completion_status == FLUSH_RETRY_TIMEOUT));
+	} while ((completion_stat == FLUSH_RETRY_PLUGGED) ||
+		 (completion_stat == FLUSH_RETRY_TIMEOUT));
+
 	time2 = get_cycles();
-	bcp->plugged_tries = 0;
-	bcp->timeout_tries = 0;
-	if ((completion_status == FLUSH_COMPLETE) &&
-	    (bcp->conseccompletes > bcp->complete_threshold) &&
-	    (hmaster->max_bau_concurrent <
-					hmaster->max_bau_concurrent_constant))
-			hmaster->max_bau_concurrent++;
+
+	count_max_concurr(completion_stat, bcp, hmaster);
+
 	while (hmaster->uvhub_quiesce)
 		cpu_relax();
+
 	atomic_dec(&hmaster->active_descriptor_count);
-	if (time2 > time1) {
-		elapsed = time2 - time1;
-		stat->s_time += elapsed;
-		if ((completion_status == FLUSH_COMPLETE) && (try == 1)) {
-			bcp->period_requests++;
-			bcp->period_time += elapsed;
-			if ((elapsed > congested_cycles) &&
-			    (bcp->period_requests > bcp->congested_reps)) {
-				disable_for_congestion(bcp, stat);
+
+	record_send_stats(time1, time2, bcp, stat, completion_stat, try);
+
+	if (completion_stat == FLUSH_GIVEUP)
+		return 1;
+	return 0;
+}
+
+/*
+ * The BAU is disabled. When the disabled time period has expired, the cpu
+ * that disabled it must re-enable it.
+ * Return 0 if it is re-enabled for all cpus.
+ */
+static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
+{
+	int tcpu;
+	struct bau_control *tbcp;
+
+	if (bcp->set_bau_off) {
+		if (get_cycles() >= bcp->set_bau_on_time) {
+			stat->s_bau_reenabled++;
+			baudisabled = 0;
+			for_each_present_cpu(tcpu) {
+				tbcp = &per_cpu(bau_control, tcpu);
+				tbcp->baudisabled = 0;
+				tbcp->period_requests = 0;
+				tbcp->period_time = 0;
 			}
+			return 0;
 		}
+	}
+	return -1;
+}
+
+static void record_send_statistics(struct ptc_stats *stat, int locals, int hubs,
+				int remotes, struct bau_desc *bau_desc)
+{
+	stat->s_requestor++;
+	stat->s_ntargcpu += remotes + locals;
+	stat->s_ntargremotes += remotes;
+	stat->s_ntarglocals += locals;
+
+	/* uvhub statistics */
+	hubs = bau_uvhub_weight(&bau_desc->distribution);
+	if (locals) {
+		stat->s_ntarglocaluvhub++;
+		stat->s_ntargremoteuvhub += (hubs - 1);
 	} else
-		stat->s_requestor--;
-	if (completion_status == FLUSH_COMPLETE && try > 1)
-		stat->s_retriesok++;
-	else if (completion_status == FLUSH_GIVEUP) {
-		stat->s_giveup++;
-		return 1;
+		stat->s_ntargremoteuvhub += hubs;
+
+	stat->s_ntarguvhub += hubs;
+
+	if (hubs >= 16)
+		stat->s_ntarguvhub16++;
+	else if (hubs >= 8)
+		stat->s_ntarguvhub8++;
+	else if (hubs >= 4)
+		stat->s_ntarguvhub4++;
+	else if (hubs >= 2)
+		stat->s_ntarguvhub2++;
+	else
+		stat->s_ntarguvhub1++;
+}
+
+/*
+ * Translate a cpu mask to the uvhub distribution mask in the BAU
+ * activation descriptor.
+ */
+static int set_distrib_bits(struct cpumask *flush_mask, struct bau_control *bcp,
+			struct bau_desc *bau_desc, int *localsp, int *remotesp)
+{
+	int cpu;
+	int pnode;
+	int cnt = 0;
+	struct hub_and_pnode *hpp;
+
+	for_each_cpu(cpu, flush_mask) {
+		/*
+		 * The distribution vector is a bit map of pnodes, relative
+		 * to the partition base pnode (and the partition base nasid
+		 * in the header).
+		 * Translate cpu to pnode and hub using a local memory array.
+		 */
+		hpp = &bcp->socket_master->thp[cpu];
+		pnode = hpp->pnode - bcp->partition_base_pnode;
+		bau_uvhub_set(pnode, &bau_desc->distribution);
+		cnt++;
+		if (hpp->uvhub == bcp->uvhub)
+			(*localsp)++;
+		else
+			(*remotesp)++;
 	}
+	if (!cnt)
+		return 1;
 	return 0;
 }
 
-/**
- * uv_flush_tlb_others - globally purge translation cache of a virtual
- * address or all TLB's
+/*
+ * globally purge translation cache of a virtual address or all TLB's
  * @cpumask: mask of all cpu's in which the address is to be removed
  * @mm: mm_struct containing virtual address range
  * @va: virtual address to be removed (or TLB_FLUSH_ALL for all TLB's on cpu)
@@ -774,20 +925,16 @@ int uv_flush_send_and_wait(struct bau_desc *bau_desc,
  * done.  The returned pointer is valid till preemption is re-enabled.
  */
 const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
-					  struct mm_struct *mm,
-					  unsigned long va, unsigned int cpu)
+				struct mm_struct *mm, unsigned long va,
+				unsigned int cpu)
 {
 	int locals = 0;
 	int remotes = 0;
 	int hubs = 0;
-	int tcpu;
-	int tpnode;
 	struct bau_desc *bau_desc;
 	struct cpumask *flush_mask;
 	struct ptc_stats *stat;
 	struct bau_control *bcp;
-	struct bau_control *tbcp;
-	struct hub_and_pnode *hpp;
 
 	/* kernel was booted 'nobau' */
 	if (nobau)
@@ -798,20 +945,8 @@ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
 
 	/* bau was disabled due to slow response */
 	if (bcp->baudisabled) {
-		/* the cpu that disabled it must re-enable it */
-		if (bcp->set_bau_off) {
-			if (get_cycles() >= bcp->set_bau_on_time) {
-				stat->s_bau_reenabled++;
-				baudisabled = 0;
-				for_each_present_cpu(tcpu) {
-					tbcp = &per_cpu(bau_control, tcpu);
-					tbcp->baudisabled = 0;
-					tbcp->period_requests = 0;
-					tbcp->period_time = 0;
-				}
-			}
-		}
-		return cpumask;
+		if (check_enable(bcp, stat))
+			return cpumask;
 	}
 
 	/*
@@ -822,59 +957,20 @@ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
 	flush_mask = (struct cpumask *)per_cpu(uv_flush_tlb_mask, cpu);
 	/* don't actually do a shootdown of the local cpu */
 	cpumask_andnot(flush_mask, cpumask, cpumask_of(cpu));
+
 	if (cpu_isset(cpu, *cpumask))
 		stat->s_ntargself++;
 
 	bau_desc = bcp->descriptor_base;
-	bau_desc += UV_ITEMS_PER_DESCRIPTOR * bcp->uvhub_cpu;
+	bau_desc += ITEMS_PER_DESC * bcp->uvhub_cpu;
 	bau_uvhubs_clear(&bau_desc->distribution, UV_DISTRIBUTION_SIZE);
-
-	for_each_cpu(tcpu, flush_mask) {
-		/*
-		 * The distribution vector is a bit map of pnodes, relative
-		 * to the partition base pnode (and the partition base nasid
-		 * in the header).
-		 * Translate cpu to pnode and hub using an array stored
-		 * in local memory.
-		 */
-		hpp = &bcp->socket_master->target_hub_and_pnode[tcpu];
-		tpnode = hpp->pnode - bcp->partition_base_pnode;
-		bau_uvhub_set(tpnode, &bau_desc->distribution);
-		if (hpp->uvhub == bcp->uvhub)
-			locals++;
-		else
-			remotes++;
-	}
-	if ((locals + remotes) == 0)
+	if (set_distrib_bits(flush_mask, bcp, bau_desc, &locals, &remotes))
 		return NULL;
-	stat->s_requestor++;
-	stat->s_ntargcpu += remotes + locals;
-	stat->s_ntargremotes += remotes;
-	stat->s_ntarglocals += locals;
-	remotes = bau_uvhub_weight(&bau_desc->distribution);
 
-	/* uvhub statistics */
-	hubs = bau_uvhub_weight(&bau_desc->distribution);
-	if (locals) {
-		stat->s_ntarglocaluvhub++;
-		stat->s_ntargremoteuvhub += (hubs - 1);
-	} else
-		stat->s_ntargremoteuvhub += hubs;
-	stat->s_ntarguvhub += hubs;
-	if (hubs >= 16)
-		stat->s_ntarguvhub16++;
-	else if (hubs >= 8)
-		stat->s_ntarguvhub8++;
-	else if (hubs >= 4)
-		stat->s_ntarguvhub4++;
-	else if (hubs >= 2)
-		stat->s_ntarguvhub2++;
-	else
-		stat->s_ntarguvhub1++;
+	record_send_statistics(stat, locals, hubs, remotes, bau_desc);
 
 	bau_desc->payload.address = va;
 	bau_desc->payload.sending_cpu = cpu;
-
 	/*
 	 * uv_flush_send_and_wait returns 0 if all cpu's were messaged,
 	 * or 1 if it gave up and the original cpumask should be returned.
@@ -903,26 +999,31 @@ void uv_bau_message_interrupt(struct pt_regs *regs)
 {
 	int count = 0;
 	cycles_t time_start;
-	struct bau_payload_queue_entry *msg;
+	struct bau_pq_entry *msg;
 	struct bau_control *bcp;
 	struct ptc_stats *stat;
 	struct msg_desc msgdesc;
 
 	time_start = get_cycles();
+
 	bcp = &per_cpu(bau_control, smp_processor_id());
 	stat = bcp->statp;
-	msgdesc.va_queue_first = bcp->va_queue_first;
-	msgdesc.va_queue_last = bcp->va_queue_last;
+
+	msgdesc.queue_first = bcp->queue_first;
+	msgdesc.queue_last = bcp->queue_last;
+
 	msg = bcp->bau_msg_head;
-	while (msg->sw_ack_vector) {
+	while (msg->swack_vec) {
 		count++;
-		msgdesc.msg_slot = msg - msgdesc.va_queue_first;
-		msgdesc.sw_ack_slot = ffs(msg->sw_ack_vector) - 1;
+
+		msgdesc.msg_slot = msg - msgdesc.queue_first;
+		msgdesc.swack_slot = ffs(msg->swack_vec) - 1;
 		msgdesc.msg = msg;
-		uv_bau_process_message(&msgdesc, bcp);
+		bau_process_message(&msgdesc, bcp);
+
 		msg++;
-		if (msg > msgdesc.va_queue_last)
-			msg = msgdesc.va_queue_first;
+		if (msg > msgdesc.queue_last)
+			msg = msgdesc.queue_first;
 		bcp->bau_msg_head = msg;
 	}
 	stat->d_time += (get_cycles() - time_start);
@@ -930,18 +1031,17 @@ void uv_bau_message_interrupt(struct pt_regs *regs)
 		stat->d_nomsg++;
 	else if (count > 1)
 		stat->d_multmsg++;
+
 	ack_APIC_irq();
 }
 
 /*
- * uv_enable_timeouts
- *
- * Each target uvhub (i.e. a uvhub that has no cpu's) needs to have
+ * Each target uvhub (i.e. a uvhub that has cpu's) needs to have
  * shootdown message timeouts enabled.  The timeout does not cause
  * an interrupt, but causes an error message to be returned to
  * the sender.
  */
-static void __init uv_enable_timeouts(void)
+static void __init enable_timeouts(void)
 {
 	int uvhub;
 	int nuvhubs;
@@ -955,52 +1055,44 @@ static void __init uv_enable_timeouts(void)
 			continue;
 
 		pnode = uv_blade_to_pnode(uvhub);
-		mmr_image =
-		    uv_read_global_mmr64(pnode, UVH_LB_BAU_MISC_CONTROL);
+		mmr_image = read_mmr_misc_control(pnode);
 		/*
 		 * Set the timeout period and then lock it in, in three
 		 * steps; captures and locks in the period.
 		 *
 		 * To program the period, the SOFT_ACK_MODE must be off.
 		 */
-		mmr_image &= ~((unsigned long)1 <<
-		    UVH_LB_BAU_MISC_CONTROL_ENABLE_INTD_SOFT_ACK_MODE_SHFT);
-		uv_write_global_mmr64
-		    (pnode, UVH_LB_BAU_MISC_CONTROL, mmr_image);
+		mmr_image &= ~(1L << SOFTACK_MSHIFT);
+		write_mmr_misc_control(pnode, mmr_image);
 		/*
 		 * Set the 4-bit period.
 		 */
-		mmr_image &= ~((unsigned long)0xf <<
-		     UVH_LB_BAU_MISC_CONTROL_INTD_SOFT_ACK_TIMEOUT_PERIOD_SHFT);
-		mmr_image |= (UV_INTD_SOFT_ACK_TIMEOUT_PERIOD <<
-		     UVH_LB_BAU_MISC_CONTROL_INTD_SOFT_ACK_TIMEOUT_PERIOD_SHFT);
-		uv_write_global_mmr64
-		    (pnode, UVH_LB_BAU_MISC_CONTROL, mmr_image);
+		mmr_image &= ~((unsigned long)0xf << SOFTACK_PSHIFT);
+		mmr_image |= (SOFTACK_TIMEOUT_PERIOD << SOFTACK_PSHIFT);
+		write_mmr_misc_control(pnode, mmr_image);
 		/*
 		 * UV1:
 		 * Subsequent reversals of the timebase bit (3) cause an
 		 * immediate timeout of one or all INTD resources as
 		 * indicated in bits 2:0 (7 causes all of them to timeout).
 		 */
-		mmr_image |= ((unsigned long)1 <<
-		    UVH_LB_BAU_MISC_CONTROL_ENABLE_INTD_SOFT_ACK_MODE_SHFT);
+		mmr_image |= (1L << SOFTACK_MSHIFT);
 		if (is_uv2_hub()) {
-			mmr_image |= ((unsigned long)1 << UV2_LEG_SHFT);
-			mmr_image |= ((unsigned long)1 << UV2_EXT_SHFT);
+			mmr_image |= (1L << UV2_LEG_SHFT);
+			mmr_image |= (1L << UV2_EXT_SHFT);
 		}
-		uv_write_global_mmr64
-		    (pnode, UVH_LB_BAU_MISC_CONTROL, mmr_image);
+		write_mmr_misc_control(pnode, mmr_image);
 	}
 }
 
-static void *uv_ptc_seq_start(struct seq_file *file, loff_t *offset)
+static void *ptc_seq_start(struct seq_file *file, loff_t *offset)
 {
 	if (*offset < num_possible_cpus())
 		return offset;
 	return NULL;
 }
 
-static void *uv_ptc_seq_next(struct seq_file *file, void *data, loff_t *offset)
+static void *ptc_seq_next(struct seq_file *file, void *data, loff_t *offset)
 {
 	(*offset)++;
 	if (*offset < num_possible_cpus())
@@ -1008,12 +1100,11 @@ static void *uv_ptc_seq_next(struct seq_file *file, void *data, loff_t *offset)
 	return NULL;
 }
 
-static void uv_ptc_seq_stop(struct seq_file *file, void *data)
+static void ptc_seq_stop(struct seq_file *file, void *data)
 {
 }
 
-static inline unsigned long long
-microsec_2_cycles(unsigned long microsec)
+static inline unsigned long long usec_2_cycles(unsigned long microsec)
 {
 	unsigned long ns;
 	unsigned long long cyc;
@@ -1024,29 +1115,27 @@ microsec_2_cycles(unsigned long microsec)
 }
 
 /*
- * Display the statistics thru /proc.
+ * Display the statistics thru /proc/sgi_uv/ptc_statistics
  * 'data' points to the cpu number
+ * Note: see the descriptions in stat_description[].
  */
-static int uv_ptc_seq_show(struct seq_file *file, void *data)
+static int ptc_seq_show(struct seq_file *file, void *data)
 {
 	struct ptc_stats *stat;
 	int cpu;
 
 	cpu = *(loff_t *)data;
-
 	if (!cpu) {
 		seq_printf(file,
 			"# cpu sent stime self locals remotes ncpus localhub ");
 		seq_printf(file,
 			"remotehub numuvhubs numuvhubs16 numuvhubs8 ");
 		seq_printf(file,
-			"numuvhubs4 numuvhubs2 numuvhubs1 dto ");
+			"numuvhubs4 numuvhubs2 numuvhubs1 dto retries rok ");
 		seq_printf(file,
-			"retries rok resetp resett giveup sto bz throt ");
+			"resetp resett giveup sto bz throt swack recv rtime ");
 		seq_printf(file,
-			"sw_ack recv rtime all ");
-		seq_printf(file,
-			"one mult none retry canc nocan reset rcan ");
+			"all one mult none retry canc nocan reset rcan ");
 		seq_printf(file,
 			"disable enable\n");
 	}
@@ -1073,8 +1162,7 @@ static int uv_ptc_seq_show(struct seq_file *file, void *data)
 		/* destination side statistics */
 		seq_printf(file,
 			   "%lx %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
-			   uv_read_global_mmr64(uv_cpu_to_pnode(cpu),
-					UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE),
+			   read_gmmr_sw_ack(uv_cpu_to_pnode(cpu)),
 			   stat->d_requestee, cycles_2_us(stat->d_time),
 			   stat->d_alltlb, stat->d_onetlb, stat->d_multmsg,
 			   stat->d_nomsg, stat->d_retries, stat->d_canceled,
@@ -1083,7 +1171,6 @@ static int uv_ptc_seq_show(struct seq_file *file, void *data)
 		seq_printf(file, "%ld %ld\n",
 			stat->s_bau_disabled, stat->s_bau_reenabled);
 	}
-
 	return 0;
 }
 
@@ -1091,18 +1178,18 @@ static int uv_ptc_seq_show(struct seq_file *file, void *data)
  * Display the tunables thru debugfs
  */
 static ssize_t tunables_read(struct file *file, char __user *userbuf,
-						size_t count, loff_t *ppos)
+				size_t count, loff_t *ppos)
 {
 	char *buf;
 	int ret;
 
 	buf = kasprintf(GFP_KERNEL, "%s %s %s\n%d %d %d %d %d %d %d %d %d\n",
-		"max_bau_concurrent plugged_delay plugsb4reset",
+		"max_concur plugged_delay plugsb4reset",
 		"timeoutsb4reset ipi_reset_limit complete_threshold",
 		"congested_response_us congested_reps congested_period",
-		max_bau_concurrent, plugged_delay, plugsb4reset,
+		max_concurr, plugged_delay, plugsb4reset,
 		timeoutsb4reset, ipi_reset_limit, complete_threshold,
-		congested_response_us, congested_reps, congested_period);
+		congested_respns_us, congested_reps, congested_period);
 
 	if (!buf)
 		return -ENOMEM;
@@ -1113,13 +1200,16 @@ static ssize_t tunables_read(struct file *file, char __user *userbuf,
 }
 
 /*
- * -1: resetf the statistics
+ * handle a write to /proc/sgi_uv/ptc_statistics
+ * -1: reset the statistics
  *  0: display meaning of the statistics
  */
-static ssize_t uv_ptc_proc_write(struct file *file, const char __user *user,
-				 size_t count, loff_t *data)
+static ssize_t ptc_proc_write(struct file *file, const char __user *user,
+				size_t count, loff_t *data)
 {
 	int cpu;
+	int i;
+	int elements;
 	long input_arg;
 	char optstr[64];
 	struct ptc_stats *stat;
@@ -1129,79 +1219,18 @@ static ssize_t uv_ptc_proc_write(struct file *file, const char __user *user,
 	if (copy_from_user(optstr, user, count))
 		return -EFAULT;
 	optstr[count - 1] = '\0';
+
 	if (strict_strtol(optstr, 10, &input_arg) < 0) {
 		printk(KERN_DEBUG "%s is invalid\n", optstr);
 		return -EINVAL;
 	}
 
 	if (input_arg == 0) {
+		elements = sizeof(stat_description)/sizeof(*stat_description);
 		printk(KERN_DEBUG "# cpu:      cpu number\n");
 		printk(KERN_DEBUG "Sender statistics:\n");
-		printk(KERN_DEBUG
-		"sent:     number of shootdown messages sent\n");
-		printk(KERN_DEBUG
-		"stime:    time spent sending messages\n");
-		printk(KERN_DEBUG
-		"numuvhubs: number of hubs targeted with shootdown\n");
-		printk(KERN_DEBUG
-		"numuvhubs16: number times 16 or more hubs targeted\n");
-		printk(KERN_DEBUG
-		"numuvhubs8: number times 8 or more hubs targeted\n");
-		printk(KERN_DEBUG
-		"numuvhubs4: number times 4 or more hubs targeted\n");
-		printk(KERN_DEBUG
-		"numuvhubs2: number times 2 or more hubs targeted\n");
-		printk(KERN_DEBUG
-		"numuvhubs1: number times 1 hub targeted\n");
-		printk(KERN_DEBUG
-		"numcpus:  number of cpus targeted with shootdown\n");
-		printk(KERN_DEBUG
-		"dto:      number of destination timeouts\n");
-		printk(KERN_DEBUG
-		"retries:  destination timeout retries sent\n");
-		printk(KERN_DEBUG
-		"rok:   :  destination timeouts successfully retried\n");
-		printk(KERN_DEBUG
-		"resetp:   ipi-style resource resets for plugs\n");
-		printk(KERN_DEBUG
-		"resett:   ipi-style resource resets for timeouts\n");
-		printk(KERN_DEBUG
-		"giveup:   fall-backs to ipi-style shootdowns\n");
-		printk(KERN_DEBUG
-		"sto:      number of source timeouts\n");
-		printk(KERN_DEBUG
-		"bz:       number of stay-busy's\n");
-		printk(KERN_DEBUG
-		"throt:    number times spun in throttle\n");
-		printk(KERN_DEBUG "Destination side statistics:\n");
-		printk(KERN_DEBUG
-		"sw_ack:   image of UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE\n");
-		printk(KERN_DEBUG
-		"recv:     shootdown messages received\n");
-		printk(KERN_DEBUG
-		"rtime:    time spent processing messages\n");
-		printk(KERN_DEBUG
-		"all:      shootdown all-tlb messages\n");
-		printk(KERN_DEBUG
-		"one:      shootdown one-tlb messages\n");
-		printk(KERN_DEBUG
-		"mult:     interrupts that found multiple messages\n");
-		printk(KERN_DEBUG
-		"none:     interrupts that found no messages\n");
-		printk(KERN_DEBUG
-		"retry:    number of retry messages processed\n");
-		printk(KERN_DEBUG
-		"canc:     number messages canceled by retries\n");
-		printk(KERN_DEBUG
-		"nocan:    number retries that found nothing to cancel\n");
-		printk(KERN_DEBUG
-		"reset:    number of ipi-style reset requests processed\n");
-		printk(KERN_DEBUG
-		"rcan:     number messages canceled by reset requests\n");
-		printk(KERN_DEBUG
-		"disable:  number times use of the BAU was disabled\n");
-		printk(KERN_DEBUG
-		"enable:   number times use of the BAU was re-enabled\n");
+		for (i = 0; i < elements; i++)
+			printk(KERN_DEBUG "%s\n", stat_description[i]);
 	} else if (input_arg == -1) {
 		for_each_present_cpu(cpu) {
 			stat = &per_cpu(ptcstats, cpu);
@@ -1228,27 +1257,18 @@ static int local_atoi(const char *name)
 }
 
 /*
- * set the tunables
- * 0 values reset them to defaults
+ * Parse the values written to /sys/kernel/debug/sgi_uv/bau_tunables.
+ * Zero values reset them to defaults.
  */
-static ssize_t tunables_write(struct file *file, const char __user *user,
-				 size_t count, loff_t *data)
+static int parse_tunables_write(struct bau_control *bcp, char *instr,
+				int count)
 {
-	int cpu;
-	int cnt = 0;
-	int val;
 	char *p;
 	char *q;
-	char instr[64];
-	struct bau_control *bcp;
-
-	if (count == 0 || count > sizeof(instr)-1)
-		return -EINVAL;
-	if (copy_from_user(instr, user, count))
-		return -EFAULT;
+	int cnt = 0;
+	int val;
+	int e = sizeof(tunables) / sizeof(*tunables);
 
-	instr[count] = '\0';
-	/* count the fields */
 	p = instr + strspn(instr, WHITESPACE);
 	q = p;
 	for (; *p; p = q + strspn(q, WHITESPACE)) {
@@ -1257,8 +1277,8 @@ static ssize_t tunables_write(struct file *file, const char __user *user,
 		if (q == p)
 			break;
 	}
-	if (cnt != 9) {
-		printk(KERN_INFO "bau tunable error: should be 9 numbers\n");
+	if (cnt != e) {
+		printk(KERN_INFO "bau tunable error: should be %d values\n", e);
 		return -EINVAL;
 	}
 
@@ -1270,97 +1290,80 @@ static ssize_t tunables_write(struct file *file, const char __user *user,
 		switch (cnt) {
 		case 0:
 			if (val == 0) {
-				max_bau_concurrent = MAX_BAU_CONCURRENT;
-				max_bau_concurrent_constant =
-							MAX_BAU_CONCURRENT;
+				max_concurr = MAX_BAU_CONCURRENT;
+				max_concurr_const = MAX_BAU_CONCURRENT;
 				continue;
 			}
-			bcp = &per_cpu(bau_control, smp_processor_id());
 			if (val < 1 || val > bcp->cpus_in_uvhub) {
 				printk(KERN_DEBUG
 				"Error: BAU max concurrent %d is invalid\n",
 				val);
 				return -EINVAL;
 			}
-			max_bau_concurrent = val;
-			max_bau_concurrent_constant = val;
-			continue;
-		case 1:
-			if (val == 0)
-				plugged_delay = PLUGGED_DELAY;
-			else
-				plugged_delay = val;
+			max_concurr = val;
+			max_concurr_const = val;
 			continue;
-		case 2:
-			if (val == 0)
-				plugsb4reset = PLUGSB4RESET;
-			else
-				plugsb4reset = val;
-			continue;
-		case 3:
-			if (val == 0)
-				timeoutsb4reset = TIMEOUTSB4RESET;
-			else
-				timeoutsb4reset = val;
-			continue;
-		case 4:
-			if (val == 0)
-				ipi_reset_limit = IPI_RESET_LIMIT;
-			else
-				ipi_reset_limit = val;
-			continue;
-		case 5:
-			if (val == 0)
-				complete_threshold = COMPLETE_THRESHOLD;
-			else
-				complete_threshold = val;
-			continue;
-		case 6:
-			if (val == 0)
-				congested_response_us = CONGESTED_RESPONSE_US;
-			else
-				congested_response_us = val;
-			continue;
-		case 7:
-			if (val == 0)
-				congested_reps = CONGESTED_REPS;
-			else
-				congested_reps = val;
-			continue;
-		case 8:
+		default:
 			if (val == 0)
-				congested_period = CONGESTED_PERIOD;
+				*tunables[cnt].tunp = tunables[cnt].deflt;
 			else
-				congested_period = val;
+				*tunables[cnt].tunp = val;
 			continue;
 		}
 		if (q == p)
 			break;
 	}
+	return 0;
+}
+
+/*
+ * Handle a write to debugfs. (/sys/kernel/debug/sgi_uv/bau_tunables)
+ */
+static ssize_t tunables_write(struct file *file, const char __user *user,
+				size_t count, loff_t *data)
+{
+	int cpu;
+	int ret;
+	char instr[100];
+	struct bau_control *bcp;
+
+	if (count == 0 || count > sizeof(instr)-1)
+		return -EINVAL;
+	if (copy_from_user(instr, user, count))
+		return -EFAULT;
+
+	instr[count] = '\0';
+
+	bcp = &per_cpu(bau_control, smp_processor_id());
+
+	ret = parse_tunables_write(bcp, instr, count);
+	if (ret)
+		return ret;
+
 	for_each_present_cpu(cpu) {
 		bcp = &per_cpu(bau_control, cpu);
-		bcp->max_bau_concurrent = max_bau_concurrent;
-		bcp->max_bau_concurrent_constant = max_bau_concurrent;
-		bcp->plugged_delay = plugged_delay;
-		bcp->plugsb4reset = plugsb4reset;
-		bcp->timeoutsb4reset = timeoutsb4reset;
-		bcp->ipi_reset_limit = ipi_reset_limit;
-		bcp->complete_threshold = complete_threshold;
-		bcp->congested_response_us = congested_response_us;
-		bcp->congested_reps = congested_reps;
-		bcp->congested_period = congested_period;
+		bcp->max_concurr =		max_concurr;
+		bcp->max_concurr_const =	max_concurr;
+		bcp->plugged_delay =		plugged_delay;
+		bcp->plugsb4reset =		plugsb4reset;
+		bcp->timeoutsb4reset =		timeoutsb4reset;
+		bcp->ipi_reset_limit =		ipi_reset_limit;
+		bcp->complete_threshold =	complete_threshold;
+		bcp->cong_response_us =		congested_respns_us;
+		bcp->cong_reps =		congested_reps;
+		bcp->cong_period =		congested_period;
 	}
 	return count;
 }
 
 static const struct seq_operations uv_ptc_seq_ops = {
-	.start		= uv_ptc_seq_start,
-	.next		= uv_ptc_seq_next,
-	.stop		= uv_ptc_seq_stop,
-	.show		= uv_ptc_seq_show
+	.start		= ptc_seq_start,
+	.next		= ptc_seq_next,
+	.stop		= ptc_seq_stop,
+	.show		= ptc_seq_show
 };
 
-static int uv_ptc_proc_open(struct inode *inode, struct file *file)
+static int ptc_proc_open(struct inode *inode, struct file *file)
 {
 	return seq_open(file, &uv_ptc_seq_ops);
 }
@@ -1371,9 +1374,9 @@ static int tunables_open(struct inode *inode, struct file *file)
 }
 
 static const struct file_operations proc_uv_ptc_operations = {
-	.open		= uv_ptc_proc_open,
+	.open		= ptc_proc_open,
 	.read		= seq_read,
-	.write		= uv_ptc_proc_write,
+	.write		= ptc_proc_write,
 	.llseek		= seq_lseek,
 	.release	= seq_release,
 };
@@ -1407,7 +1410,7 @@ static int __init uv_ptc_init(void)
 		return -EINVAL;
 	}
 	tunables_file = debugfs_create_file(UV_BAU_TUNABLES_FILE, 0600,
-			tunables_dir, NULL, &tunables_fops);
+					tunables_dir, NULL, &tunables_fops);
 	if (!tunables_file) {
 		printk(KERN_ERR "unable to create debugfs file %s\n",
 		       UV_BAU_TUNABLES_FILE);
@@ -1419,24 +1422,24 @@ static int __init uv_ptc_init(void)
 /*
  * Initialize the sending side's sending buffers.
  */
-static void
-uv_activation_descriptor_init(int node, int pnode, int base_pnode)
+static void activation_descriptor_init(int node, int pnode, int base_pnode)
 {
 	int i;
 	int cpu;
 	unsigned long pa;
 	unsigned long m;
 	unsigned long n;
+	size_t dsize;
 	struct bau_desc *bau_desc;
 	struct bau_desc *bd2;
 	struct bau_control *bcp;
 
 	/*
-	 * each bau_desc is 64 bytes; there are 8 (UV_ITEMS_PER_DESCRIPTOR)
-	 * per cpu; and one per cpu on the uvhub (UV_ADP_SIZE)
+	 * each bau_desc is 64 bytes; there are 8 (ITEMS_PER_DESC)
+	 * per cpu; and one per cpu on the uvhub (ADP_SZ)
 	 */
-	bau_desc = kmalloc_node(sizeof(struct bau_desc) * UV_ADP_SIZE
-				* UV_ITEMS_PER_DESCRIPTOR, GFP_KERNEL, node);
+	dsize = sizeof(struct bau_desc) * ADP_SZ * ITEMS_PER_DESC;
+	bau_desc = kmalloc_node(dsize, GFP_KERNEL, node);
 	BUG_ON(!bau_desc);
 
 	pa = uv_gpa(bau_desc); /* need the real nasid*/
@@ -1444,27 +1447,25 @@ uv_activation_descriptor_init(int node, int pnode, int base_pnode)
 	m = pa & uv_mmask;
 
 	/* the 14-bit pnode */
-	uv_write_global_mmr64(pnode, UVH_LB_BAU_SB_DESCRIPTOR_BASE,
-			      (n << UV_DESC_BASE_PNODE_SHIFT | m));
+	write_mmr_descriptor_base(pnode, (n << UV_DESC_PSHIFT | m));
 	/*
-	 * Initializing all 8 (UV_ITEMS_PER_DESCRIPTOR) descriptors for each
+	 * Initializing all 8 (ITEMS_PER_DESC) descriptors for each
 	 * cpu even though we only use the first one; one descriptor can
 	 * describe a broadcast to 256 uv hubs.
 	 */
-	for (i = 0, bd2 = bau_desc; i < (UV_ADP_SIZE*UV_ITEMS_PER_DESCRIPTOR);
-		i++, bd2++) {
+	for (i = 0, bd2 = bau_desc; i < (ADP_SZ * ITEMS_PER_DESC); i++, bd2++) {
 		memset(bd2, 0, sizeof(struct bau_desc));
-		bd2->header.sw_ack_flag = 1;
+		bd2->header.swack_flag =	1;
 		/*
 		 * The base_dest_nasid set in the message header is the nasid
 		 * of the first uvhub in the partition. The bit map will
 		 * indicate destination pnode numbers relative to that base.
 		 * They may not be consecutive if nasid striding is being used.
 		 */
-		bd2->header.base_dest_nasid = UV_PNODE_TO_NASID(base_pnode);
-		bd2->header.dest_subnodeid = UV_LB_SUBNODEID;
-		bd2->header.command = UV_NET_ENDPOINT_INTD;
-		bd2->header.int_both = 1;
+		bd2->header.base_dest_nasid =	UV_PNODE_TO_NASID(base_pnode);
+		bd2->header.dest_subnodeid =	UV_LB_SUBNODEID;
+		bd2->header.command =		UV_NET_ENDPOINT_INTD;
+		bd2->header.int_both =		1;
 		/*
 		 * all others need to be set to zero:
 		 *   fairness chaining multilevel count replied_to
@@ -1484,57 +1485,55 @@ uv_activation_descriptor_init(int node, int pnode, int base_pnode)
  * - node is first node (kernel memory notion) on the uvhub
  * - pnode is the uvhub's physical identifier
  */
-static void
-uv_payload_queue_init(int node, int pnode)
+static void pq_init(int node, int pnode)
 {
-	int pn;
 	int cpu;
+	size_t plsize;
 	char *cp;
-	unsigned long pa;
-	struct bau_payload_queue_entry *pqp;
-	struct bau_payload_queue_entry *pqp_malloc;
+	void *vp;
+	unsigned long pn;
+	unsigned long first;
+	unsigned long pn_first;
+	unsigned long last;
+	struct bau_pq_entry *pqp;
 	struct bau_control *bcp;
 
-	pqp = kmalloc_node((DEST_Q_SIZE + 1)
-			   * sizeof(struct bau_payload_queue_entry),
-			   GFP_KERNEL, node);
+	plsize = (DEST_Q_SIZE + 1) * sizeof(struct bau_pq_entry);
+	vp = kmalloc_node(plsize, GFP_KERNEL, node);
+	pqp = (struct bau_pq_entry *)vp;
 	BUG_ON(!pqp);
-	pqp_malloc = pqp;
 
 	cp = (char *)pqp + 31;
-	pqp = (struct bau_payload_queue_entry *)(((unsigned long)cp >> 5) << 5);
+	pqp = (struct bau_pq_entry *)(((unsigned long)cp >> 5) << 5);
 
 	for_each_present_cpu(cpu) {
 		if (pnode != uv_cpu_to_pnode(cpu))
 			continue;
 		/* for every cpu on this pnode: */
 		bcp = &per_cpu(bau_control, cpu);
-		bcp->va_queue_first = pqp;
-		bcp->bau_msg_head = pqp;
-		bcp->va_queue_last = pqp + (DEST_Q_SIZE - 1);
+		bcp->queue_first	= pqp;
+		bcp->bau_msg_head	= pqp;
+		bcp->queue_last		= pqp + (DEST_Q_SIZE - 1);
 	}
 	/*
 	 * need the pnode of where the memory was really allocated
 	 */
-	pa = uv_gpa(pqp);
-	pn = pa >> uv_nshift;
-	uv_write_global_mmr64(pnode,
-			      UVH_LB_BAU_INTD_PAYLOAD_QUEUE_FIRST,
-			      ((unsigned long)pn << UV_PAYLOADQ_PNODE_SHIFT) |
-			      uv_physnodeaddr(pqp));
-	uv_write_global_mmr64(pnode, UVH_LB_BAU_INTD_PAYLOAD_QUEUE_TAIL,
-			      uv_physnodeaddr(pqp));
-	uv_write_global_mmr64(pnode, UVH_LB_BAU_INTD_PAYLOAD_QUEUE_LAST,
-			      (unsigned long)
-			      uv_physnodeaddr(pqp + (DEST_Q_SIZE - 1)));
+	pn = uv_gpa(pqp) >> uv_nshift;
+	first = uv_physnodeaddr(pqp);
+	pn_first = ((unsigned long)pn << UV_PAYLOADQ_PNODE_SHIFT) | first;
+	last = uv_physnodeaddr(pqp + (DEST_Q_SIZE - 1));
+	write_mmr_payload_first(pnode, pn_first);
+	write_mmr_payload_tail(pnode, first);
+	write_mmr_payload_last(pnode, last);
+
 	/* in effect, all msg_type's are set to MSG_NOOP */
-	memset(pqp, 0, sizeof(struct bau_payload_queue_entry) * DEST_Q_SIZE);
+	memset(pqp, 0, sizeof(struct bau_pq_entry) * DEST_Q_SIZE);
 }
 
 /*
  * Initialization of each UV hub's structures
  */
-static void __init uv_init_uvhub(int uvhub, int vector, int base_pnode)
+static void __init init_uvhub(int uvhub, int vector, int base_pnode)
 {
 	int node;
 	int pnode;
@@ -1542,24 +1541,24 @@ static void __init uv_init_uvhub(int uvhub, int vector, int base_pnode)
 
 	node = uvhub_to_first_node(uvhub);
 	pnode = uv_blade_to_pnode(uvhub);
-	uv_activation_descriptor_init(node, pnode, base_pnode);
-	uv_payload_queue_init(node, pnode);
+
+	activation_descriptor_init(node, pnode, base_pnode);
+
+	pq_init(node, pnode);
 	/*
 	 * The below initialization can't be in firmware because the
 	 * messaging IRQ will be determined by the OS.
 	 */
 	apicid = uvhub_to_first_apicid(uvhub) | uv_apicid_hibits;
-	uv_write_global_mmr64(pnode, UVH_BAU_DATA_CONFIG,
-				      ((apicid << 32) | vector));
+	write_mmr_data_config(pnode, ((apicid << 32) | vector));
 }
 
 /*
  * We will set BAU_MISC_CONTROL with a timeout period.
  * But the BIOS has set UVH_AGING_PRESCALE_SEL and UVH_TRANSACTION_TIMEOUT.
- * So the destination timeout period has be be calculated from them.
+ * So the destination timeout period has to be calculated from them.
  */
-static int
-calculate_destination_timeout(void)
+static int calculate_destination_timeout(void)
 {
 	unsigned long mmr_image;
 	int mult1;
@@ -1570,8 +1569,7 @@ calculate_destination_timeout(void)
 	unsigned long ts_ns;
 
 	if (is_uv1_hub()) {
-		mult1 = UV1_INTD_SOFT_ACK_TIMEOUT_PERIOD &
-			BAU_MISC_CONTROL_MULT_MASK;
+		mult1 = SOFTACK_TIMEOUT_PERIOD & BAU_MISC_CONTROL_MULT_MASK;
 		mmr_image = uv_read_local_mmr(UVH_AGING_PRESCALE_SEL);
 		index = (mmr_image >> BAU_URGENCY_7_SHIFT) & BAU_URGENCY_7_MASK;
 		mmr_image = uv_read_local_mmr(UVH_TRANSACTION_TIMEOUT);
@@ -1583,7 +1581,7 @@ calculate_destination_timeout(void)
 		/* 4 bits  0/1 for 10/80us, 3 bits of multiplier */
 		mmr_image = uv_read_local_mmr(UVH_AGING_PRESCALE_SEL);
 		mmr_image = (mmr_image & UV_SA_MASK) >> UV_SA_SHFT;
-		if (mmr_image & ((unsigned long)1 << UV2_ACK_UNITS_SHFT))
+		if (mmr_image & (1L << UV2_ACK_UNITS_SHFT))
 			mult1 = 80;
 		else
 			mult1 = 10;
@@ -1593,62 +1591,69 @@ calculate_destination_timeout(void)
 	return ret;
 }
 
+static void __init init_per_cpu_tunables(void)
+{
+	int cpu;
+	struct bau_control *bcp;
+
+	for_each_present_cpu(cpu) {
+		bcp = &per_cpu(bau_control, cpu);
+		bcp->baudisabled		= 0;
+		bcp->statp			= &per_cpu(ptcstats, cpu);
+		/* time interval to catch a hardware stay-busy bug */
+		bcp->timeout_interval		= usec_2_cycles(2*timeout_us);
+		bcp->max_concurr		= max_concurr;
+		bcp->max_concurr_const		= max_concurr;
+		bcp->plugged_delay		= plugged_delay;
+		bcp->plugsb4reset		= plugsb4reset;
+		bcp->timeoutsb4reset		= timeoutsb4reset;
+		bcp->ipi_reset_limit		= ipi_reset_limit;
+		bcp->complete_threshold		= complete_threshold;
+		bcp->cong_response_us		= congested_respns_us;
+		bcp->cong_reps			= congested_reps;
+		bcp->cong_period		= congested_period;
+	}
+}
+
 /*
- * initialize the bau_control structure for each cpu
+ * Scan all cpus to collect blade and socket summaries.
  */
-static int __init uv_init_per_cpu(int nuvhubs, int base_part_pnode)
+static int __init get_cpu_topology(int base_pnode,
+					struct uvhub_desc *uvhub_descs,
+					unsigned char *uvhub_mask)
 {
-	int i;
 	int cpu;
-	int tcpu;
 	int pnode;
 	int uvhub;
-	int have_hmaster;
-	short socket = 0;
-	unsigned short socket_mask;
-	unsigned char *uvhub_mask;
+	int socket;
 	struct bau_control *bcp;
 	struct uvhub_desc *bdp;
 	struct socket_desc *sdp;
-	struct bau_control *hmaster = NULL;
-	struct bau_control *smaster = NULL;
-	struct socket_desc {
-		short num_cpus;
-		short cpu_number[MAX_CPUS_PER_SOCKET];
-	};
-	struct uvhub_desc {
-		unsigned short socket_mask;
-		short num_cpus;
-		short uvhub;
-		short pnode;
-		struct socket_desc socket[2];
-	};
-	struct uvhub_desc *uvhub_descs;
 
-	timeout_us = calculate_destination_timeout();
-
-	uvhub_descs = kmalloc(nuvhubs * sizeof(struct uvhub_desc), GFP_KERNEL);
-	memset(uvhub_descs, 0, nuvhubs * sizeof(struct uvhub_desc));
-	uvhub_mask = kzalloc((nuvhubs+7)/8, GFP_KERNEL);
 	for_each_present_cpu(cpu) {
 		bcp = &per_cpu(bau_control, cpu);
+
 		memset(bcp, 0, sizeof(struct bau_control));
+
 		pnode = uv_cpu_hub_info(cpu)->pnode;
-		if ((pnode - base_part_pnode) >= UV_DISTRIBUTION_SIZE) {
+		if ((pnode - base_pnode) >= UV_DISTRIBUTION_SIZE) {
 			printk(KERN_EMERG
 				"cpu %d pnode %d-%d beyond %d; BAU disabled\n",
-				cpu, pnode, base_part_pnode,
-				UV_DISTRIBUTION_SIZE);
+				cpu, pnode, base_pnode, UV_DISTRIBUTION_SIZE);
 			return 1;
 		}
+
 		bcp->osnode = cpu_to_node(cpu);
-		bcp->partition_base_pnode = uv_partition_base_pnode;
+		bcp->partition_base_pnode = base_pnode;
+
 		uvhub = uv_cpu_hub_info(cpu)->numa_blade_id;
 		*(uvhub_mask + (uvhub/8)) |= (1 << (uvhub%8));
 		bdp = &uvhub_descs[uvhub];
+
 		bdp->num_cpus++;
 		bdp->uvhub = uvhub;
 		bdp->pnode = pnode;
+
 		/* kludge: 'assuming' one node per socket, and assuming that
 		   disabling a socket just leaves a gap in node numbers */
 		socket = bcp->osnode & 1;
@@ -1657,84 +1662,129 @@ static int __init uv_init_per_cpu(int nuvhubs, int base_part_pnode)
 		sdp->cpu_number[sdp->num_cpus] = cpu;
 		sdp->num_cpus++;
 		if (sdp->num_cpus > MAX_CPUS_PER_SOCKET) {
-			printk(KERN_EMERG "%d cpus per socket invalid\n", sdp->num_cpus);
+			printk(KERN_EMERG "%d cpus per socket invalid\n",
+				sdp->num_cpus);
 			return 1;
 		}
 	}
+	return 0;
+}
+
+/*
+ * Each socket is to get a local array of pnodes/hubs.
+ */
+static void make_per_cpu_thp(struct bau_control *smaster)
+{
+	int cpu;
+	size_t hpsz = sizeof(struct hub_and_pnode) * num_possible_cpus();
+
+	smaster->thp = kmalloc_node(hpsz, GFP_KERNEL, smaster->osnode);
+	memset(smaster->thp, 0, hpsz);
+	for_each_present_cpu(cpu) {
+		smaster->thp[cpu].pnode = uv_cpu_hub_info(cpu)->pnode;
+		smaster->thp[cpu].uvhub = uv_cpu_hub_info(cpu)->numa_blade_id;
+	}
+}
+
+/*
+ * Initialize all the per_cpu information for the cpu's on a given socket,
+ * given what has been gathered into the socket_desc struct.
+ * And reports the chosen hub and socket masters back to the caller.
+ */
+static int scan_sock(struct socket_desc *sdp, struct uvhub_desc *bdp,
+			struct bau_control **smasterp,
+			struct bau_control **hmasterp)
+{
+	int i;
+	int cpu;
+	struct bau_control *bcp;
+
+	for (i = 0; i < sdp->num_cpus; i++) {
+		cpu = sdp->cpu_number[i];
+		bcp = &per_cpu(bau_control, cpu);
+		bcp->cpu = cpu;
+		if (i == 0) {
+			*smasterp = bcp;
+			if (!(*hmasterp))
+				*hmasterp = bcp;
+		}
+		bcp->cpus_in_uvhub = bdp->num_cpus;
+		bcp->cpus_in_socket = sdp->num_cpus;
+		bcp->socket_master = *smasterp;
+		bcp->uvhub = bdp->uvhub;
+		bcp->uvhub_master = *hmasterp;
+		bcp->uvhub_cpu = uv_cpu_hub_info(cpu)->blade_processor_id;
+		if (bcp->uvhub_cpu >= MAX_CPUS_PER_UVHUB) {
+			printk(KERN_EMERG "%d cpus per uvhub invalid\n",
+				bcp->uvhub_cpu);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Summarize the blade and socket topology into the per_cpu structures.
+ */
+static int __init summarize_uvhub_sockets(int nuvhubs,
+			struct uvhub_desc *uvhub_descs,
+			unsigned char *uvhub_mask)
+{
+	int socket;
+	int uvhub;
+	unsigned short socket_mask;
+
 	for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
+		struct uvhub_desc *bdp;
+		struct bau_control *smaster = NULL;
+		struct bau_control *hmaster = NULL;
+
 		if (!(*(uvhub_mask + (uvhub/8)) & (1 << (uvhub%8))))
 			continue;
-		have_hmaster = 0;
+
 		bdp = &uvhub_descs[uvhub];
 		socket_mask = bdp->socket_mask;
 		socket = 0;
 		while (socket_mask) {
-			if (!(socket_mask & 1))
-				goto nextsocket;
-			sdp = &bdp->socket[socket];
-			for (i = 0; i < sdp->num_cpus; i++) {
-				cpu = sdp->cpu_number[i];
-				bcp = &per_cpu(bau_control, cpu);
-				bcp->cpu = cpu;
-				if (i == 0) {
-					smaster = bcp;
-					if (!have_hmaster) {
-						have_hmaster++;
-						hmaster = bcp;
-					}
-				}
-				bcp->cpus_in_uvhub = bdp->num_cpus;
-				bcp->cpus_in_socket = sdp->num_cpus;
-				bcp->socket_master = smaster;
-				bcp->uvhub = bdp->uvhub;
-				bcp->uvhub_master = hmaster;
-				bcp->uvhub_cpu = uv_cpu_hub_info(cpu)->
-						blade_processor_id;
-				if (bcp->uvhub_cpu >= MAX_CPUS_PER_UVHUB) {
-					printk(KERN_EMERG
-						"%d cpus per uvhub invalid\n",
-						bcp->uvhub_cpu);
+			struct socket_desc *sdp;
+			if ((socket_mask & 1)) {
+				sdp = &bdp->socket[socket];
+				if (scan_sock(sdp, bdp, &smaster, &hmaster))
 					return 1;
-				}
 			}
-nextsocket:
 			socket++;
 			socket_mask = (socket_mask >> 1);
-			/* each socket gets a local array of pnodes/hubs */
-			bcp = smaster;
-			bcp->target_hub_and_pnode = kmalloc_node(
-				sizeof(struct hub_and_pnode) *
-				num_possible_cpus(), GFP_KERNEL, bcp->osnode);
-			memset(bcp->target_hub_and_pnode, 0,
-				sizeof(struct hub_and_pnode) *
-				num_possible_cpus());
-			for_each_present_cpu(tcpu) {
-				bcp->target_hub_and_pnode[tcpu].pnode =
-					uv_cpu_hub_info(tcpu)->pnode;
-				bcp->target_hub_and_pnode[tcpu].uvhub =
-					uv_cpu_hub_info(tcpu)->numa_blade_id;
-			}
+			make_per_cpu_thp(smaster);
 		}
 	}
+	return 0;
+}
+
+/*
+ * initialize the bau_control structure for each cpu
+ */
+static int __init init_per_cpu(int nuvhubs, int base_part_pnode)
+{
+	unsigned char *uvhub_mask;
+	void *vp;
+	struct uvhub_desc *uvhub_descs;
+
+	timeout_us = calculate_destination_timeout();
+
+	vp = kmalloc(nuvhubs * sizeof(struct uvhub_desc), GFP_KERNEL);
+	uvhub_descs = (struct uvhub_desc *)vp;
+	memset(uvhub_descs, 0, nuvhubs * sizeof(struct uvhub_desc));
+	uvhub_mask = kzalloc((nuvhubs+7)/8, GFP_KERNEL);
+
+	if (get_cpu_topology(base_part_pnode, uvhub_descs, uvhub_mask))
+		return 1;
+
+	if (summarize_uvhub_sockets(nuvhubs, uvhub_descs, uvhub_mask))
+		return 1;
+
 	kfree(uvhub_descs);
 	kfree(uvhub_mask);
-	for_each_present_cpu(cpu) {
-		bcp = &per_cpu(bau_control, cpu);
-		bcp->baudisabled = 0;
-		bcp->statp = &per_cpu(ptcstats, cpu);
-		/* time interval to catch a hardware stay-busy bug */
-		bcp->timeout_interval = microsec_2_cycles(2*timeout_us);
-		bcp->max_bau_concurrent = max_bau_concurrent;
-		bcp->max_bau_concurrent_constant = max_bau_concurrent;
-		bcp->plugged_delay = plugged_delay;
-		bcp->plugsb4reset = plugsb4reset;
-		bcp->timeoutsb4reset = timeoutsb4reset;
-		bcp->ipi_reset_limit = ipi_reset_limit;
-		bcp->complete_threshold = complete_threshold;
-		bcp->congested_response_us = congested_response_us;
-		bcp->congested_reps = congested_reps;
-		bcp->congested_period = congested_period;
-	}
+	init_per_cpu_tunables();
 	return 0;
 }
 
@@ -1747,8 +1797,9 @@ static int __init uv_bau_init(void)
 	int pnode;
 	int nuvhubs;
 	int cur_cpu;
+	int cpus;
 	int vector;
-	unsigned long mmr;
+	cpumask_var_t *mask;
 
 	if (!is_uv_system())
 		return 0;
@@ -1756,24 +1807,25 @@ static int __init uv_bau_init(void)
 	if (nobau)
 		return 0;
 
-	for_each_possible_cpu(cur_cpu)
-		zalloc_cpumask_var_node(&per_cpu(uv_flush_tlb_mask, cur_cpu),
-				       GFP_KERNEL, cpu_to_node(cur_cpu));
+	for_each_possible_cpu(cur_cpu) {
+		mask = &per_cpu(uv_flush_tlb_mask, cur_cpu);
+		zalloc_cpumask_var_node(mask, GFP_KERNEL, cpu_to_node(cur_cpu));
+	}
 
 	uv_nshift = uv_hub_info->m_val;
 	uv_mmask = (1UL << uv_hub_info->m_val) - 1;
 	nuvhubs = uv_num_possible_blades();
 	spin_lock_init(&disable_lock);
-	congested_cycles = microsec_2_cycles(congested_response_us);
+	congested_cycles = usec_2_cycles(congested_respns_us);
 
-	uv_partition_base_pnode = 0x7fffffff;
+	uv_base_pnode = 0x7fffffff;
 	for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
-		if (uv_blade_nr_possible_cpus(uvhub) &&
-			(uv_blade_to_pnode(uvhub) < uv_partition_base_pnode))
-			uv_partition_base_pnode = uv_blade_to_pnode(uvhub);
+		cpus = uv_blade_nr_possible_cpus(uvhub);
+		if (cpus && (uv_blade_to_pnode(uvhub) < uv_base_pnode))
+			uv_base_pnode = uv_blade_to_pnode(uvhub);
 	}
 
-	if (uv_init_per_cpu(nuvhubs, uv_partition_base_pnode)) {
+	if (init_per_cpu(nuvhubs, uv_base_pnode)) {
 		nobau = 1;
 		return 0;
 	}
@@ -1781,21 +1833,21 @@ static int __init uv_bau_init(void)
 	vector = UV_BAU_MESSAGE;
 	for_each_possible_blade(uvhub)
 		if (uv_blade_nr_possible_cpus(uvhub))
-			uv_init_uvhub(uvhub, vector, uv_partition_base_pnode);
+			init_uvhub(uvhub, vector, uv_base_pnode);
 
-	uv_enable_timeouts();
+	enable_timeouts();
 	alloc_intr_gate(vector, uv_bau_message_intr1);
 
 	for_each_possible_blade(uvhub) {
 		if (uv_blade_nr_possible_cpus(uvhub)) {
+			unsigned long val;
+			unsigned long mmr;
 			pnode = uv_blade_to_pnode(uvhub);
 			/* INIT the bau */
-			uv_write_global_mmr64(pnode,
-					UVH_LB_BAU_SB_ACTIVATION_CONTROL,
-					((unsigned long)1 << 63));
+			val = 1L << 63;
+			write_gmmr_activation(pnode, val);
 			mmr = 1; /* should be 1 to broadcast to both sockets */
-			uv_write_global_mmr64(pnode, UVH_BAU_DATA_BROADCAST,
-						mmr);
+			write_mmr_data_broadcast(pnode, mmr);
 		}
 	}