1 files changed, 40 insertions, 64 deletions

diff --git a/drivers/s390/cio/qdio_thinint.c b/drivers/s390/cio/qdio_thinint.c
index 8daf1b99f153..5c4e741d8221 100644
--- a/drivers/s390/cio/qdio_thinint.c
+++ b/drivers/s390/cio/qdio_thinint.c
@@ -8,6 +8,7 @@
  */
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/kernel_stat.h>
 #include <asm/atomic.h>
 #include <asm/debug.h>
 #include <asm/qdio.h>
@@ -25,35 +26,17 @@
  */
 #define TIQDIO_NR_NONSHARED_IND         63
 #define TIQDIO_NR_INDICATORS            (TIQDIO_NR_NONSHARED_IND + 1)
-#define TIQDIO_SHARED_IND               63
 
 /* list of thin interrupt input queues */
 static LIST_HEAD(tiq_list);
 DEFINE_MUTEX(tiq_list_lock);
 
 /* adapter local summary indicator */
-static unsigned char *tiqdio_alsi;
+static u8 *tiqdio_alsi;
 
-/* device state change indicators */
-struct indicator_t {
-        u32 ind;        /* u32 because of compare-and-swap performance */
-        atomic_t count; /* use count, 0 or 1 for non-shared indicators */
-};
-static struct indicator_t *q_indicators;
+struct indicator_t *q_indicators;
 
-static int css_qdio_omit_svs;
-
-static inline unsigned long do_clear_global_summary(void)
-{
-        register unsigned long __fn asm("1") = 3;
-        register unsigned long __tmp asm("2");
-        register unsigned long __time asm("3");
-
-        asm volatile(
-                "       .insn   rre,0xb2650000,2,0"
-                : "+d" (__fn), "=d" (__tmp), "=d" (__time));
-        return __time;
-}
+static u64 last_ai_time;
 
 /* returns addr for the device state change indicator */
 static u32 *get_indicator(void)
@@ -87,10 +70,6 @@ void tiqdio_add_input_queues(struct qdio_irq *irq_ptr)
         struct qdio_q *q;
         int i;
 
-        /* No TDD facility? If we must use SIGA-s we can also omit SVS. */
-        if (!css_qdio_omit_svs && irq_ptr->siga_flag.sync)
-                css_qdio_omit_svs = 1;
-
         mutex_lock(&tiq_list_lock);
         for_each_input_queue(irq_ptr, q, i)
                 list_add_rcu(&q->entry, &tiq_list);
@@ -116,65 +95,68 @@ void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr)
         }
 }
 
-static inline int shared_ind(struct qdio_irq *irq_ptr)
+static inline u32 shared_ind_set(void)
 {
-        return irq_ptr->dsci == &q_indicators[TIQDIO_SHARED_IND].ind;
+        return q_indicators[TIQDIO_SHARED_IND].ind;
 }
 
 /**
  * tiqdio_thinint_handler - thin interrupt handler for qdio
- * @ind: pointer to adapter local summary indicator
- * @drv_data: NULL
+ * @alsi: pointer to adapter local summary indicator
+ * @data: NULL
  */
-static void tiqdio_thinint_handler(void *ind, void *drv_data)
+static void tiqdio_thinint_handler(void *alsi, void *data)
 {
+        u32 si_used = shared_ind_set();
         struct qdio_q *q;
 
-        /*
-         * SVS only when needed: issue SVS to benefit from iqdio interrupt
-         * avoidance (SVS clears adapter interrupt suppression overwrite)
-         */
-        if (!css_qdio_omit_svs)
-                do_clear_global_summary();
-
-        /*
-         * reset local summary indicator (tiqdio_alsi) to stop adapter
-         * interrupts for now
-         */
-        xchg((u8 *)ind, 0);
+        last_ai_time = S390_lowcore.int_clock;
+        kstat_cpu(smp_processor_id()).irqs[IOINT_QAI]++;
 
         /* protect tiq_list entries, only changed in activate or shutdown */
         rcu_read_lock();
 
         /* check for work on all inbound thinint queues */
-        list_for_each_entry_rcu(q, &tiq_list, entry)
+        list_for_each_entry_rcu(q, &tiq_list, entry) {
+
                 /* only process queues from changed sets */
-                if (*q->irq_ptr->dsci) {
-                        qperf_inc(q, adapter_int);
+                if (unlikely(shared_ind(q->irq_ptr->dsci))) {
+                        if (!si_used)
+                                continue;
+                } else if (!*q->irq_ptr->dsci)
+                        continue;
 
+                if (q->u.in.queue_start_poll) {
+                        /* skip if polling is enabled or already in work */
+                        if (test_and_set_bit(QDIO_QUEUE_IRQS_DISABLED,
+                                             &q->u.in.queue_irq_state)) {
+                                qperf_inc(q, int_discarded);
+                                continue;
+                        }
+
+                        /* avoid dsci clear here, done after processing */
+                        q->u.in.queue_start_poll(q->irq_ptr->cdev, q->nr,
+                                                 q->irq_ptr->int_parm);
+                } else {
                         /* only clear it if the indicator is non-shared */
-                        if (!shared_ind(q->irq_ptr))
+                        if (!shared_ind(q->irq_ptr->dsci))
                                 xchg(q->irq_ptr->dsci, 0);
                         /*
-                         * don't call inbound processing directly since
-                         * that could starve other thinint queues
+                         * Call inbound processing but not directly
+                         * since that could starve other thinint queues.
                          */
                         tasklet_schedule(&q->tasklet);
                 }
-
+                qperf_inc(q, adapter_int);
+        }
         rcu_read_unlock();
 
         /*
-         * if we used the shared indicator clear it now after all queues
-         * were processed
+         * If the shared indicator was used clear it now after all queues
+         * were processed.
          */
-        if (atomic_read(&q_indicators[TIQDIO_SHARED_IND].count)) {
+        if (si_used && shared_ind_set())
                 xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 0);
-
-                /* prevent racing */
-                if (*tiqdio_alsi)
-                        xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 1 << 7);
-        }
 }
 
 static int set_subchannel_ind(struct qdio_irq *irq_ptr, int reset)
@@ -259,12 +241,6 @@ int qdio_establish_thinint(struct qdio_irq *irq_ptr)
 {
         if (!is_thinint_irq(irq_ptr))
                 return 0;
-
-        /* Check for aif time delay disablement. If installed,
-         * omit SVS even under LPAR
-         */
-        if (css_general_characteristics.aif_tdd)
-                css_qdio_omit_svs = 1;
         return set_subchannel_ind(irq_ptr, 0);
 }
 
@@ -282,8 +258,8 @@ void qdio_shutdown_thinint(struct qdio_irq *irq_ptr)
                 return;
 
         /* reset adapter interrupt indicators */
-        put_indicator(irq_ptr->dsci);
         set_subchannel_ind(irq_ptr, 1);
+        put_indicator(irq_ptr->dsci);
 }
 
 void __exit tiqdio_unregister_thinints(void)