x86, UV: Modularize BAU send and wait

Streamline the large uv_flush_send_and_wait() function by use of
a couple of helper functions.

And remove some excess comments.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: gregkh@suse.de
LKML-Reference: <E1OJvNy-0004ay-IH@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 44 insertions, 39 deletions

diff --git a/arch/x86/include/asm/uv/uv_bau.h b/arch/x86/include/asm/uv/uv_bau.h
index 7f6ea611cb71..42d412fd8b02 100644
--- a/arch/x86/include/asm/uv/uv_bau.h
+++ b/arch/x86/include/asm/uv/uv_bau.h
@@ -75,7 +75,6 @@
 #define DESC_STATUS_DESTINATION_TIMEOUT 2
 #define DESC_STATUS_SOURCE_TIMEOUT      3
 
-#define TIMEOUT_DELAY                   10
 /*
  * delay for 'plugged' timeout retries, in microseconds
  */
diff --git a/arch/x86/kernel/tlb_uv.c b/arch/x86/kernel/tlb_uv.c
index a1615058fad3..abf3c31f14cf 100644
--- a/arch/x86/kernel/tlb_uv.c
+++ b/arch/x86/kernel/tlb_uv.c
@@ -485,6 +485,47 @@ static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u)
 }
 
 /*
+ * Our retries are blocked by all destination swack 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,
+                        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);
+                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)
+{
+        hmaster->max_bau_concurrent = 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);
+                spin_unlock(&hmaster->queue_lock);
+                end_uvhub_quiesce(hmaster);
+                bcp->ipi_attempts++;
+                stat->s_resets_timeout++;
+        }
+}
+
+/*
  * Completions are taking a very long time due to a congested numalink
  * network.
  */
@@ -518,7 +559,7 @@ disable_for_congestion(struct bau_control *bcp, struct ptc_stats *stat)
  *
  * Send a broadcast and wait for it to complete.
  *
- * The flush_mask contains the cpus the broadcast is to be sent to, plus
+ * The flush_mask contains the cpus the broadcast is to be sent to including
  * cpus that are on the local uvhub.
  *
  * Returns 0 if all flushing represented in the mask was done.
@@ -553,7 +594,6 @@ int uv_flush_send_and_wait(struct bau_desc *bau_desc,
                         &hmaster->active_descriptor_count,
                         hmaster->max_bau_concurrent));
         }
-
         while (hmaster->uvhub_quiesce)
                 cpu_relax();
 
@@ -584,40 +624,9 @@ int uv_flush_send_and_wait(struct bau_desc *bau_desc,
                         right_shift, this_cpu, bcp, smaster, try);
 
                 if (completion_status == FLUSH_RETRY_PLUGGED) {
-                        /*
-                         * Our retries may be blocked by all destination swack
-                         * resources being consumed, and a timeout pending. In
-                         * that case hardware immediately returns the ERROR
-                         * that looks like a destination timeout.
-                         */
-                        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,
-                                                        this_cpu);
-                                spin_unlock(&hmaster->queue_lock);
-                                end_uvhub_quiesce(hmaster);
-                                bcp->ipi_attempts++;
-                                stat->s_resets_plug++;
-                        }
+                        destination_plugged(bau_desc, bcp, hmaster, stat);
                 } else if (completion_status == FLUSH_RETRY_TIMEOUT) {
-                        hmaster->max_bau_concurrent = 1;
-                        bcp->timeout_tries++;
-                        udelay(TIMEOUT_DELAY);
-                        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,
-                                                                this_cpu);
-                                spin_unlock(&hmaster->queue_lock);
-                                end_uvhub_quiesce(hmaster);
-                                bcp->ipi_attempts++;
-                                stat->s_resets_timeout++;
-                        }
+                        destination_timeout(bau_desc, bcp, hmaster, stat);
                 }
                 if (bcp->ipi_attempts >= bcp->ipi_reset_limit) {
                         bcp->ipi_attempts = 0;
@@ -628,10 +637,8 @@ int uv_flush_send_and_wait(struct bau_desc *bau_desc,
         } while ((completion_status == FLUSH_RETRY_PLUGGED) ||
                  (completion_status == 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 <
@@ -740,7 +747,6 @@ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
 
         bau_desc = bcp->descriptor_base;
         bau_desc += UV_ITEMS_PER_DESCRIPTOR * bcp->uvhub_cpu;
-
         bau_uvhubs_clear(&bau_desc->distribution, UV_DISTRIBUTION_SIZE);
 
         /* cpu statistics */