[PATCH 3/3] x86: UV2 BAU hang workarounds

From: Cliff Wickman
Date: Fri Jun 22 2012 - 09:14:57 EST

On SGI's UV2 the BAU (Broadcast Assist Unit) driver can hang under a
heavy load. To cure this:

- Disable the UV2 extended status mode (see UV2_EXT_SHFT), as this
mode changes BAU behavior in more ways then just delivering an extra bit
of status. Revert status to just two meaningful bits, like UV1.
- Use no IPI-style resets on UV2. Just give up the request for whatever the
reason it failed and let it be accomplished with the legacy IPI method.
- Use no alternate sending descriptor (the former UV2 workaround
bcp->using_desc and handle_uv2_busy() stuff). Just disable the use of the
BAU for a period of time in favor of the legacy IPI method when the h/w bug
leaves a descriptor busy.
-- new tunable: giveup_limit determines the threshold at which a hub is
so plugged that it should do all requests with the legacy IPI method for a
period of time
-- generalize disable_for_congestion() (renamed disable_for_period()) for
use whenever a hub should avoid using the BAU for a period of time

Misc:
- fix find_another_by_swack(), which is part of the UV2 bug workaround
- correct and clarify the statistics (new stats s_overipilimit s_giveuplimit
s_enters s_ipifordisabled s_plugged s_congested)

Signed-off-by: Cliff Wickman <cpw@xxxxxxx>
---
arch/x86/include/asm/uv/uv_bau.h | 28 +-
arch/x86/platform/uv/tlb_uv.c | 385 ++++++++++++++++++---------------------
2 files changed, 199 insertions(+), 214 deletions(-)

Index: linus.current/arch/x86/include/asm/uv/uv_bau.h
===================================================================
--- linus.current.orig/arch/x86/include/asm/uv/uv_bau.h
+++ linus.current/arch/x86/include/asm/uv/uv_bau.h
@@ -140,6 +140,9 @@
#define IPI_RESET_LIMIT 1
/* after this # consecutive successes, bump up the throttle if it was lowered */
#define COMPLETE_THRESHOLD 5
+/* after this # of giveups (fall back to kernel IPI's) disable the use of
+ the BAU for a period of time */
+#define GIVEUP_LIMIT 100

#define UV_LB_SUBNODEID 0x10

@@ -166,7 +169,6 @@
#define FLUSH_RETRY_TIMEOUT 2
#define FLUSH_GIVEUP 3
#define FLUSH_COMPLETE 4
-#define FLUSH_RETRY_BUSYBUG 5

/*
* tuning the action when the numalink network is extremely delayed
@@ -175,7 +177,7 @@
microseconds */
#define CONGESTED_REPS 10 /* long delays averaged over
this many broadcasts */
-#define CONGESTED_PERIOD 30 /* time for the bau to be
+#define DISABLED_PERIOD 10 /* time for the bau to be
disabled, in seconds */
/* see msg_type: */
#define MSG_NOOP 0
@@ -520,7 +522,12 @@ struct ptc_stats {
unsigned long s_uv2_wars; /* uv2 workaround, perm. busy */
unsigned long s_uv2_wars_hw; /* uv2 workaround, hiwater */
unsigned long s_uv2_war_waits; /* uv2 workaround, long waits */
- unsigned long s_enters; /* entries to the driver */
+ unsigned long s_overipilimit; /* over the ipi reset limit */
+ unsigned long s_giveuplimit; /* disables, over giveup limit*/
+ unsigned long s_enters; /* entries to the driver */
+ unsigned long s_ipifordisabled; /* fall back to IPI; disabled */
+ unsigned long s_plugged; /* plugged by h/w bug*/
+ unsigned long s_congested; /* giveup on long wait */
/* destination statistics */
unsigned long d_alltlb; /* times all tlb's on this
cpu were flushed */
@@ -588,8 +595,7 @@ struct bau_control {
int ipi_attempts;
int conseccompletes;
short nobau;
- int baudisabled;
- int set_bau_off;
+ short baudisabled;
short cpu;
short osnode;
short uvhub_cpu;
@@ -598,14 +604,16 @@ struct bau_control {
short cpus_in_socket;
short cpus_in_uvhub;
short partition_base_pnode;
- short using_desc; /* an index, like uvhub_cpu */
- unsigned int inuse_map;
+ short busy; /* all were busy (war) */
unsigned short message_number;
unsigned short uvhub_quiesce;
short socket_acknowledge_count[DEST_Q_SIZE];
cycles_t send_message;
+ cycles_t period_end;
+ cycles_t period_time;
spinlock_t uvhub_lock;
spinlock_t queue_lock;
+ spinlock_t disable_lock;
/* tunables */
int max_concurr;
int max_concurr_const;
@@ -616,9 +624,9 @@ struct bau_control {
int complete_threshold;
int cong_response_us;
int cong_reps;
- int cong_period;
- unsigned long clocks_per_100_usec;
- cycles_t period_time;
+ cycles_t disabled_period;
+ int period_giveups;
+ int giveup_limit;
long period_requests;
struct hub_and_pnode *thp;
};
Index: linus.current/arch/x86/platform/uv/tlb_uv.c
===================================================================
--- linus.current.orig/arch/x86/platform/uv/tlb_uv.c
+++ linus.current/arch/x86/platform/uv/tlb_uv.c
@@ -1,7 +1,7 @@
/*
* SGI UltraViolet TLB flush routines.
*
- * (c) 2008-2011 Cliff Wickman <cpw@xxxxxxx>, SGI.
+ * (c) 2008-2012 Cliff Wickman <cpw@xxxxxxx>, SGI.
*
* This code is released under the GNU General Public License version 2 or
* later.
@@ -39,8 +39,6 @@ static int timeout_base_ns[] = {
static int timeout_us;
static int nobau;
static int nobau_perm;
-static int baudisabled;
-static spinlock_t disable_lock;
static cycles_t congested_cycles;

/* tunables: */
@@ -48,12 +46,13 @@ static int max_concurr = MAX_BAU_CONCUR
static int max_concurr_const = MAX_BAU_CONCURRENT;
static int plugged_delay = PLUGGED_DELAY;
static int plugsb4reset = PLUGSB4RESET;
+static int giveup_limit = GIVEUP_LIMIT;
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 int disabled_period = DISABLED_PERIOD;

static struct tunables tunables[] = {
{&max_concurr, MAX_BAU_CONCURRENT}, /* must be [0] */
@@ -64,7 +63,8 @@ static struct tunables tunables[] = {
{&complete_threshold, COMPLETE_THRESHOLD},
{&congested_respns_us, CONGESTED_RESPONSE_US},
{&congested_reps, CONGESTED_REPS},
- {&congested_period, CONGESTED_PERIOD}
+ {&disabled_period, DISABLED_PERIOD},
+ {&giveup_limit, GIVEUP_LIMIT}
};

static struct dentry *tunables_dir;
@@ -313,7 +313,7 @@ static void bau_process_message(struct m
* Both sockets dump their completed count total into
* the message's count.
*/
- smaster->socket_acknowledge_count[mdp->msg_slot] = 0;
+ *sp = 0;
asp = (struct atomic_short *)&msg->acknowledge_count;
msg_ack_count = atom_asr(socket_ack_count, asp);

@@ -526,16 +526,15 @@ static int uv1_wait_completion(struct ba
}

/*
- * UV2 has an extra bit of status in the ACTIVATION_STATUS_2 register.
+ * UV2 could have an extra bit of status in the ACTIVATION_STATUS_2 register.
+ * But not currently used.
*/
static unsigned long uv2_read_status(unsigned long offset, int rshft, int desc)
{
unsigned long descriptor_status;
- unsigned long descriptor_status2;

- descriptor_status = ((read_lmmr(offset) >> rshft) & UV_ACT_STATUS_MASK);
- descriptor_status2 = (read_mmr_uv2_status() >> desc) & 0x1UL;
- descriptor_status = (descriptor_status << 1) | descriptor_status2;
+ descriptor_status =
+ ((read_lmmr(offset) >> rshft) & UV_ACT_STATUS_MASK) << 1;
return descriptor_status;
}

@@ -566,87 +565,11 @@ int normal_busy(struct bau_control *bcp)
*/
int handle_uv2_busy(struct bau_control *bcp)
{
- int busy_one = bcp->using_desc;
- int normal = bcp->uvhub_cpu;
- int selected = -1;
- int i;
- unsigned long descriptor_status;
- unsigned long status;
- int mmr_offset;
- struct bau_desc *bau_desc_old;
- struct bau_desc *bau_desc_new;
- struct bau_control *hmaster = bcp->uvhub_master;
struct ptc_stats *stat = bcp->statp;
- cycles_t ttm;

stat->s_uv2_wars++;
- spin_lock(&hmaster->uvhub_lock);
- /* try for the original first */
- if (busy_one != normal) {
- if (!normal_busy(bcp))
- selected = normal;
- }
- if (selected < 0) {
- /* can't use the normal, select an alternate */
- mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_1;
- descriptor_status = read_lmmr(mmr_offset);
-
- /* scan available descriptors 32-63 */
- for (i = 0; i < UV_CPUS_PER_AS; i++) {
- if ((hmaster->inuse_map & (1 << i)) == 0) {
- status = ((descriptor_status >>
- (i * UV_ACT_STATUS_SIZE)) &
- UV_ACT_STATUS_MASK) << 1;
- if (status != UV2H_DESC_BUSY) {
- selected = i + UV_CPUS_PER_AS;
- break;
- }
- }
- }
- }
-
- if (busy_one != normal)
- /* mark the busy alternate as not in-use */
- hmaster->inuse_map &= ~(1 << (busy_one - UV_CPUS_PER_AS));
-
- if (selected >= 0) {
- /* switch to the selected descriptor */
- if (selected != normal) {
- /* set the selected alternate as in-use */
- hmaster->inuse_map |=
- (1 << (selected - UV_CPUS_PER_AS));
- if (selected > stat->s_uv2_wars_hw)
- stat->s_uv2_wars_hw = selected;
- }
- bau_desc_old = bcp->descriptor_base;
- bau_desc_old += (ITEMS_PER_DESC * busy_one);
- bcp->using_desc = selected;
- bau_desc_new = bcp->descriptor_base;
- bau_desc_new += (ITEMS_PER_DESC * selected);
- *bau_desc_new = *bau_desc_old;
- } else {
- /*
- * All are busy. Wait for the normal one for this cpu to
- * free up.
- */
- stat->s_uv2_war_waits++;
- spin_unlock(&hmaster->uvhub_lock);
- ttm = get_cycles();
- do {
- cpu_relax();
- } while (normal_busy(bcp));
- spin_lock(&hmaster->uvhub_lock);
- /* switch to the original descriptor */
- bcp->using_desc = normal;
- bau_desc_old = bcp->descriptor_base;
- bau_desc_old += (ITEMS_PER_DESC * bcp->using_desc);
- bcp->using_desc = (ITEMS_PER_DESC * normal);
- bau_desc_new = bcp->descriptor_base;
- bau_desc_new += (ITEMS_PER_DESC * normal);
- *bau_desc_new = *bau_desc_old; /* copy the entire descriptor */
- }
- spin_unlock(&hmaster->uvhub_lock);
- return FLUSH_RETRY_BUSYBUG;
+ bcp->busy = 1;
+ return FLUSH_GIVEUP;
}

static int uv2_wait_completion(struct bau_desc *bau_desc,
@@ -655,7 +578,7 @@ static int uv2_wait_completion(struct ba
{
unsigned long descriptor_stat;
cycles_t ttm;
- int desc = bcp->using_desc;
+ int desc = bcp->uvhub_cpu;
long busy_reps = 0;
struct ptc_stats *stat = bcp->statp;

@@ -663,24 +586,38 @@ static int uv2_wait_completion(struct ba

/* spin on the status MMR, waiting for it to go 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_stat == UV2H_DESC_SOURCE_TIMEOUT) ||
- (descriptor_stat == UV2H_DESC_DEST_PUT_ERR)) {
+ if ((descriptor_stat == UV2H_DESC_SOURCE_TIMEOUT)) {
+ /*
+ * A h/w bug on the destination side may
+ * have prevented the message being marked
+ * pending, thus it doesn't get replied to
+ * and gets continually nacked until it times
+ * out with a SOURCE_TIMEOUT.
+ */
stat->s_stimeout++;
return FLUSH_GIVEUP;
- } else if (descriptor_stat == UV2H_DESC_DEST_STRONG_NACK) {
- stat->s_strongnacks++;
- bcp->conseccompletes = 0;
- return FLUSH_GIVEUP;
} else if (descriptor_stat == UV2H_DESC_DEST_TIMEOUT) {
+ 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.
+ * Without using the extended status we have to
+ * deduce from the short time that this was a
+ * strong nack.
+ */
+ if (cycles_2_us(ttm - bcp->send_message) < timeout_us) {
+ bcp->conseccompletes = 0;
+ stat->s_plugged++;
+ /* FLUSH_RETRY_PLUGGED causes hang on boot */
+ return FLUSH_GIVEUP;
+ }
stat->s_dtimeout++;
bcp->conseccompletes = 0;
- return FLUSH_RETRY_TIMEOUT;
+ /* FLUSH_RETRY_TIMEOUT causes hang on boot */
+ return FLUSH_GIVEUP;
} else {
busy_reps++;
if (busy_reps > 1000000) {
@@ -688,9 +625,8 @@ static int uv2_wait_completion(struct ba
busy_reps = 0;
ttm = get_cycles();
if ((ttm - bcp->send_message) >
- (bcp->clocks_per_100_usec)) {
+ bcp->timeout_interval)
return handle_uv2_busy(bcp);
- }
}
/*
* descriptor_stat is still BUSY
@@ -714,7 +650,7 @@ static int wait_completion(struct bau_de
{
int right_shift;
unsigned long mmr_offset;
- int desc = bcp->using_desc;
+ int desc = bcp->uvhub_cpu;

if (desc < UV_CPUS_PER_AS) {
mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_0;
@@ -793,33 +729,31 @@ static void destination_timeout(struct b
}

/*
- * Completions are taking a very long time due to a congested numalink
- * network.
+ * Stop all cpus on a uvhub from using the BAU for a period of time.
+ * This is reversed by check_enable.
*/
-static void disable_for_congestion(struct bau_control *bcp,
- struct ptc_stats *stat)
+static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
{
- /* let only one cpu do this disabling */
- spin_lock(&disable_lock);
+ int tcpu;
+ struct bau_control *tbcp;
+ struct bau_control *hmaster;
+ cycles_t tm1;

- 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();
- bcp->set_bau_on_time += sec_2_cycles(bcp->cong_period);
+ hmaster = bcp->uvhub_master;
+ spin_lock(&hmaster->disable_lock);
+ if (!bcp->baudisabled) {
stat->s_bau_disabled++;
+ tm1 = get_cycles();
for_each_present_cpu(tcpu) {
tbcp = &per_cpu(bau_control, tcpu);
- tbcp->baudisabled = 1;
+ if (tbcp->uvhub_master == hmaster) {
+ tbcp->baudisabled = 1;
+ tbcp->set_bau_on_time =
+ tm1 + bcp->disabled_period;
+ }
}
}
-
- spin_unlock(&disable_lock);
+ spin_unlock(&hmaster->disable_lock);
}

static void count_max_concurr(int stat, struct bau_control *bcp,
@@ -850,16 +784,30 @@ static void record_send_stats(cycles_t t
bcp->period_requests++;
bcp->period_time += elapsed;
if ((elapsed > congested_cycles) &&
- (bcp->period_requests > bcp->cong_reps))
- disable_for_congestion(bcp, stat);
+ (bcp->period_requests > bcp->cong_reps) &&
+ ((bcp->period_time / bcp->period_requests) >
+ congested_cycles)) {
+ stat->s_congested++;
+ disable_for_period(bcp, stat);
+ }
}
} else
stat->s_requestor--;

if (completion_status == FLUSH_COMPLETE && try > 1)
stat->s_retriesok++;
- else if (completion_status == FLUSH_GIVEUP)
+ else if (completion_status == FLUSH_GIVEUP) {
stat->s_giveup++;
+ if (get_cycles() > bcp->period_end)
+ bcp->period_giveups = 0;
+ bcp->period_giveups++;
+ if (bcp->period_giveups == 1)
+ bcp->period_end = get_cycles() + bcp->disabled_period;
+ if (bcp->period_giveups > bcp->giveup_limit) {
+ disable_for_period(bcp, stat);
+ stat->s_giveuplimit++;
+ }
+ }
}

/*
@@ -903,7 +851,8 @@ static void handle_cmplt(int completion_
* Returns 1 if it gives up entirely and the original cpu mask is to be
* returned to the kernel.
*/
-int uv_flush_send_and_wait(struct cpumask *flush_mask, struct bau_control *bcp)
+int uv_flush_send_and_wait(struct cpumask *flush_mask, struct bau_control *bcp,
+ struct bau_desc *bau_desc)
{
int seq_number = 0;
int completion_stat = 0;
@@ -916,24 +865,23 @@ int uv_flush_send_and_wait(struct cpumas
struct bau_control *hmaster = bcp->uvhub_master;
struct uv1_bau_msg_header *uv1_hdr = NULL;
struct uv2_bau_msg_header *uv2_hdr = NULL;
- struct bau_desc *bau_desc;

- if (bcp->uvhub_version == 1)
+ if (bcp->uvhub_version == 1) {
+ uv1 = 1;
uv1_throttle(hmaster, stat);
+ }

while (hmaster->uvhub_quiesce)
cpu_relax();

time1 = get_cycles();
+ if (uv1)
+ uv1_hdr = &bau_desc->header.uv1_hdr;
+ else
+ uv2_hdr = &bau_desc->header.uv2_hdr;
+
do {
- bau_desc = bcp->descriptor_base;
- bau_desc += (ITEMS_PER_DESC * bcp->using_desc);
- if (bcp->uvhub_version == 1) {
- uv1 = 1;
- uv1_hdr = &bau_desc->header.uv1_hdr;
- } else
- uv2_hdr = &bau_desc->header.uv2_hdr;
- if ((try == 0) || (completion_stat == FLUSH_RETRY_BUSYBUG)) {
+ if (try == 0) {
if (uv1)
uv1_hdr->msg_type = MSG_REGULAR;
else
@@ -951,25 +899,24 @@ int uv_flush_send_and_wait(struct cpumas
uv1_hdr->sequence = seq_number;
else
uv2_hdr->sequence = seq_number;
- index = (1UL << AS_PUSH_SHIFT) | bcp->using_desc;
+ index = (1UL << AS_PUSH_SHIFT) | bcp->uvhub_cpu;
bcp->send_message = get_cycles();

write_mmr_activation(index);

try++;
completion_stat = wait_completion(bau_desc, bcp, try);
- /* UV2: wait_completion() may change the bcp->using_desc */

handle_cmplt(completion_stat, bau_desc, bcp, hmaster, stat);

if (bcp->ipi_attempts >= bcp->ipi_reset_limit) {
bcp->ipi_attempts = 0;
+ stat->s_overipilimit++;
completion_stat = FLUSH_GIVEUP;
break;
}
cpu_relax();
} while ((completion_stat == FLUSH_RETRY_PLUGGED) ||
- (completion_stat == FLUSH_RETRY_BUSYBUG) ||
(completion_stat == FLUSH_RETRY_TIMEOUT));

time2 = get_cycles();
@@ -990,28 +937,33 @@ int uv_flush_send_and_wait(struct cpumas
}

/*
- * 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.
+ * The BAU is disabled for this uvhub. When the disabled time period has
+ * expired re-enable it.
+ * Return 0 if it is re-enabled for all cpus on this uvhub.
*/
static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
{
int tcpu;
struct bau_control *tbcp;
+ struct bau_control *hmaster;

- 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);
+ hmaster = bcp->uvhub_master;
+ spin_lock(&hmaster->disable_lock);
+ if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) {
+ stat->s_bau_reenabled++;
+ for_each_present_cpu(tcpu) {
+ tbcp = &per_cpu(bau_control, tcpu);
+ if (tbcp->uvhub_master == hmaster) {
tbcp->baudisabled = 0;
tbcp->period_requests = 0;
tbcp->period_time = 0;
+ tbcp->period_giveups = 0;
}
- return 0;
}
+ spin_unlock(&hmaster->disable_lock);
+ return 0;
}
+ spin_unlock(&hmaster->disable_lock);
return -1;
}

@@ -1113,6 +1065,8 @@ const struct cpumask *uv_flush_tlb_other
struct cpumask *flush_mask;
struct ptc_stats *stat;
struct bau_control *bcp;
+ unsigned long descriptor_status;
+ unsigned long status;

bcp = &per_cpu(bau_control, cpu);
stat = bcp->statp;
@@ -1121,10 +1075,22 @@ const struct cpumask *uv_flush_tlb_other
if (bcp->nobau)
return cpumask;

+ if (bcp->busy) {
+ descriptor_status =
+ read_lmmr(UVH_LB_BAU_SB_ACTIVATION_STATUS_0);
+ status = ((descriptor_status >> (bcp->uvhub_cpu *
+ UV_ACT_STATUS_SIZE)) & UV_ACT_STATUS_MASK) << 1;
+ if (status == UV2H_DESC_BUSY)
+ return cpumask;
+ bcp->busy = 0;
+ }
+
/* bau was disabled due to slow response */
if (bcp->baudisabled) {
- if (check_enable(bcp, stat))
+ if (check_enable(bcp, stat)) {
+ stat->s_ipifordisabled++;
return cpumask;
+ }
}

/*
@@ -1140,7 +1106,7 @@ const struct cpumask *uv_flush_tlb_other
stat->s_ntargself++;

bau_desc = bcp->descriptor_base;
- bau_desc += (ITEMS_PER_DESC * bcp->using_desc);
+ bau_desc += (ITEMS_PER_DESC * bcp->uvhub_cpu);
bau_uvhubs_clear(&bau_desc->distribution, UV_DISTRIBUTION_SIZE);
if (set_distrib_bits(flush_mask, bcp, bau_desc, &locals, &remotes))
return NULL;
@@ -1153,25 +1119,27 @@ const struct cpumask *uv_flush_tlb_other
* 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.
*/
- if (!uv_flush_send_and_wait(flush_mask, bcp))
+ if (!uv_flush_send_and_wait(flush_mask, bcp, bau_desc))
return NULL;
else
return cpumask;
}

/*
- * Search the message queue for any 'other' message with the same software
- * acknowledge resource bit vector.
+ * Search the message queue for any 'other' unprocessed message with the
+ * same software acknowledge resource bit vector as the 'msg' message.
*/
struct bau_pq_entry *find_another_by_swack(struct bau_pq_entry *msg,
- struct bau_control *bcp, unsigned char swack_vec)
+ struct bau_control *bcp)
{
struct bau_pq_entry *msg_next = msg + 1;
+ unsigned char swack_vec = msg->swack_vec;

if (msg_next > bcp->queue_last)
msg_next = bcp->queue_first;
- while ((msg_next->swack_vec != 0) && (msg_next != msg)) {
- if (msg_next->swack_vec == swack_vec)
+ while (msg_next != msg) {
+ if ((msg_next->canceled == 0) && (msg_next->replied_to == 0) &&
+ (msg_next->swack_vec == swack_vec))
return msg_next;
msg_next++;
if (msg_next > bcp->queue_last)
@@ -1200,32 +1168,30 @@ void process_uv2_message(struct msg_desc
* This message was assigned a swack resource, but no
* reserved acknowlegment is pending.
* The bug has prevented this message from setting the MMR.
- * And no other message has used the same sw_ack resource.
- * Do the requested shootdown but do not reply to the msg.
- * (the 0 means make no acknowledge)
*/
- bau_process_message(mdp, bcp, 0);
- return;
- }
-
- /*
- * Some message has set the MMR 'pending' bit; it might have been
- * another message. Look for that message.
- */
- other_msg = find_another_by_swack(msg, bcp, msg->swack_vec);
- if (other_msg) {
- /* There is another. Do not ack the current one. */
- bau_process_message(mdp, bcp, 0);
/*
- * Let the natural processing of that message acknowledge
- * it. Don't get the processing of sw_ack's out of order.
+ * Some message has set the MMR 'pending' bit; it might have
+ * been another message. Look for that message.
*/
- return;
+ other_msg = find_another_by_swack(msg, bcp);
+ if (other_msg) {
+ /*
+ * There is another. Process this one but do not
+ * ack it.
+ */
+ bau_process_message(mdp, bcp, 0);
+ /*
+ * Let the natural processing of that other message
+ * acknowledge it. Don't get the processing of sw_ack's
+ * out of order.
+ */
+ return;
+ }
}

/*
- * There is no other message using this sw_ack, so it is safe to
- * acknowledge it.
+ * Either the MMR shows this one pending a reply or there is no
+ * other message using this sw_ack, so it is safe to acknowledge it.
*/
bau_process_message(mdp, bcp, 1);

@@ -1330,7 +1296,8 @@ static void __init enable_timeouts(void)
*/
mmr_image |= (1L << SOFTACK_MSHIFT);
if (is_uv2_hub()) {
- mmr_image |= (1L << UV2_EXT_SHFT);
+ /* hw bug workaround; do not use extended status */
+ mmr_image &= ~(1L << UV2_EXT_SHFT);
}
write_mmr_misc_control(pnode, mmr_image);
}
@@ -1379,24 +1346,26 @@ static int ptc_seq_show(struct seq_file
cpu = *(loff_t *)data;
if (!cpu) {
seq_printf(file,
- "# cpu bauoff sent stime self locals remotes ncpus localhub ");
+ "# cpu bauoff sent stime self locals remotes ncpus localhub ");
seq_printf(file,
"remotehub numuvhubs numuvhubs16 numuvhubs8 ");
seq_printf(file,
- "numuvhubs4 numuvhubs2 numuvhubs1 dto snacks retries rok ");
+ "numuvhubs4 numuvhubs2 numuvhubs1 dto snacks retries ");
+ seq_printf(file,
+ "rok resetp resett giveup sto bz throt disable ");
seq_printf(file,
- "resetp resett giveup sto bz throt enters swack recv rtime ");
+ "enable wars warshw warwaits enters ipidis plugged ");
seq_printf(file,
- "all one mult none retry canc nocan reset rcan ");
+ "ipiover glim cong swack recv rtime all one mult ");
seq_printf(file,
- "disable enable wars warshw warwaits\n");
+ "none retry canc nocan reset rcan\n");
}
if (cpu < num_possible_cpus() && cpu_online(cpu)) {
bcp = &per_cpu(bau_control, cpu);
stat = bcp->statp;
/* source side statistics */
seq_printf(file,
- "cpu %d %d %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
+ "cpu %d %d %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
cpu, bcp->nobau, stat->s_requestor,
cycles_2_us(stat->s_time),
stat->s_ntargself, stat->s_ntarglocals,
@@ -1407,25 +1376,28 @@ static int ptc_seq_show(struct seq_file
stat->s_ntarguvhub8, stat->s_ntarguvhub4,
stat->s_ntarguvhub2, stat->s_ntarguvhub1,
stat->s_dtimeout, stat->s_strongnacks);
- seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld %ld ",
+ seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld ",
stat->s_retry_messages, stat->s_retriesok,
stat->s_resets_plug, stat->s_resets_timeout,
stat->s_giveup, stat->s_stimeout,
- stat->s_busy, stat->s_throttles, stat->s_enters);
+ stat->s_busy, stat->s_throttles);
+ seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
+ stat->s_bau_disabled, stat->s_bau_reenabled,
+ stat->s_uv2_wars, stat->s_uv2_wars_hw,
+ stat->s_uv2_war_waits, stat->s_enters,
+ stat->s_ipifordisabled, stat->s_plugged,
+ stat->s_overipilimit, stat->s_giveuplimit,
+ stat->s_congested);

/* destination side statistics */
seq_printf(file,
- "%lx %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
+ "%lx %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld\n",
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,
stat->d_nocanceled, stat->d_resets,
stat->d_rcanceled);
- seq_printf(file, "%ld %ld %ld %ld %ld\n",
- stat->s_bau_disabled, stat->s_bau_reenabled,
- stat->s_uv2_wars, stat->s_uv2_wars_hw,
- stat->s_uv2_war_waits);
}
return 0;
}
@@ -1439,13 +1411,14 @@ static ssize_t tunables_read(struct file
char *buf;
int ret;

- buf = kasprintf(GFP_KERNEL, "%s %s %s\n%d %d %d %d %d %d %d %d %d\n",
- "max_concur plugged_delay plugsb4reset",
- "timeoutsb4reset ipi_reset_limit complete_threshold",
- "congested_response_us congested_reps congested_period",
+ buf = kasprintf(GFP_KERNEL, "%s %s %s\n%d %d %d %d %d %d %d %d %d %d\n",
+ "max_concur plugged_delay plugsb4reset timeoutsb4reset",
+ "ipi_reset_limit complete_threshold congested_response_us",
+ "congested_reps disabled_period giveup_limit",
max_concurr, plugged_delay, plugsb4reset,
timeoutsb4reset, ipi_reset_limit, complete_threshold,
- congested_respns_us, congested_reps, congested_period);
+ congested_respns_us, congested_reps, disabled_period,
+ giveup_limit);

if (!buf)
return -ENOMEM;
@@ -1616,7 +1589,8 @@ static ssize_t tunables_write(struct fil
bcp->complete_threshold = complete_threshold;
bcp->cong_response_us = congested_respns_us;
bcp->cong_reps = congested_reps;
- bcp->cong_period = congested_period;
+ bcp->disabled_period = sec_2_cycles(disabled_period);
+ bcp->giveup_limit = giveup_limit;
}
return count;
}
@@ -1745,6 +1719,10 @@ static void activation_descriptor_init(i
* fairness chaining multilevel count replied_to
*/
} else {
+ /*
+ * BIOS uses legacy mode, but UV2 hardware always
+ * uses native mode for selective broadcasts.
+ */
uv2_hdr = &bd2->header.uv2_hdr;
uv2_hdr->swack_flag = 1;
uv2_hdr->base_dest_nasid =
@@ -1896,10 +1874,11 @@ static void __init init_per_cpu_tunables
bcp->complete_threshold = complete_threshold;
bcp->cong_response_us = congested_respns_us;
bcp->cong_reps = congested_reps;
- bcp->cong_period = congested_period;
- bcp->clocks_per_100_usec = usec_2_cycles(100);
+ bcp->disabled_period = sec_2_cycles(disabled_period);
+ bcp->giveup_limit = giveup_limit;
spin_lock_init(&bcp->queue_lock);
spin_lock_init(&bcp->uvhub_lock);
+ spin_lock_init(&bcp->disable_lock);
}
}

@@ -2020,7 +1999,6 @@ static int scan_sock(struct socket_desc
}
bcp->uvhub_master = *hmasterp;
bcp->uvhub_cpu = uv_cpu_hub_info(cpu)->blade_processor_id;
- bcp->using_desc = bcp->uvhub_cpu;
if (bcp->uvhub_cpu >= MAX_CPUS_PER_UVHUB) {
printk(KERN_EMERG "%d cpus per uvhub invalid\n",
bcp->uvhub_cpu);
@@ -2123,7 +2101,6 @@ static int __init uv_bau_init(void)
}

nuvhubs = uv_num_possible_blades();
- spin_lock_init(&disable_lock);
congested_cycles = usec_2_cycles(congested_respns_us);

uv_base_pnode = 0x7fffffff;
--
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