3 files changed, 51 insertions, 41 deletions

diff --git a/include/linux/average.h b/include/linux/average.h
index d04aa58280de..7ddaf340d2ac 100644
--- a/include/linux/average.h
+++ b/include/linux/average.h
@@ -1,45 +1,66 @@
 #ifndef _LINUX_AVERAGE_H
 #define _LINUX_AVERAGE_H
 
-/* Exponentially weighted moving average (EWMA) */
+/*
+ * Exponentially weighted moving average (EWMA)
+ *
+ * This implements a fixed-precision EWMA algorithm, with both the
+ * precision and fall-off coefficient determined at compile-time
+ * and built into the generated helper funtions.
+ *
+ * The first argument to the macro is the name that will be used
+ * for the struct and helper functions.
+ *
+ * The second argument, the precision, expresses how many bits are
+ * used for the fractional part of the fixed-precision values.
+ *
+ * The third argument, the weight reciprocal, determines how the
+ * new values will be weighed vs. the old state, new values will
+ * get weight 1/weight_rcp and old values 1-1/weight_rcp. Note
+ * that this parameter must be a power of two for efficiency.
+ */
 
-#define DECLARE_EWMA(name, _factor, _weight)                            \
+#define DECLARE_EWMA(name, _precision, _weight_rcp)                     \
         struct ewma_##name {                                            \
                 unsigned long internal;                                 \
         };                                                              \
         static inline void ewma_##name##_init(struct ewma_##name *e)    \
         {                                                               \
-                BUILD_BUG_ON(!__builtin_constant_p(_factor));           \
-                BUILD_BUG_ON(!__builtin_constant_p(_weight));           \
-                BUILD_BUG_ON_NOT_POWER_OF_2(_factor);                   \
-                BUILD_BUG_ON_NOT_POWER_OF_2(_weight);                   \
+                BUILD_BUG_ON(!__builtin_constant_p(_precision));        \
+                BUILD_BUG_ON(!__builtin_constant_p(_weight_rcp));       \
+                /*                                                      \
+                 * Even if you want to feed it just 0/1 you should have \
+                 * some bits for the non-fractional part...             \
+                 */                                                     \
+                BUILD_BUG_ON((_precision) > 30);                        \
+                BUILD_BUG_ON_NOT_POWER_OF_2(_weight_rcp);               \
                 e->internal = 0;                                        \
         }                                                               \
         static inline unsigned long                                     \
         ewma_##name##_read(struct ewma_##name *e)                       \
         {                                                               \
-                BUILD_BUG_ON(!__builtin_constant_p(_factor));           \
-                BUILD_BUG_ON(!__builtin_constant_p(_weight));           \
-                BUILD_BUG_ON_NOT_POWER_OF_2(_factor);                   \
-                BUILD_BUG_ON_NOT_POWER_OF_2(_weight);                   \
-                return e->internal >> ilog2(_factor);                   \
+                BUILD_BUG_ON(!__builtin_constant_p(_precision));        \
+                BUILD_BUG_ON(!__builtin_constant_p(_weight_rcp));       \
+                BUILD_BUG_ON((_precision) > 30);                        \
+                BUILD_BUG_ON_NOT_POWER_OF_2(_weight_rcp);               \
+                return e->internal >> (_precision);                     \
         }                                                               \
         static inline void ewma_##name##_add(struct ewma_##name *e,     \
                                              unsigned long val)         \
         {                                                               \
                 unsigned long internal = ACCESS_ONCE(e->internal);      \
-                unsigned long weight = ilog2(_weight);                  \
-                unsigned long factor = ilog2(_factor);                  \
+                unsigned long weight_rcp = ilog2(_weight_rcp);          \
+                unsigned long precision = _precision;                   \
                                                                         \
-                BUILD_BUG_ON(!__builtin_constant_p(_factor));           \
-                BUILD_BUG_ON(!__builtin_constant_p(_weight));           \
-                BUILD_BUG_ON_NOT_POWER_OF_2(_factor);                   \
-                BUILD_BUG_ON_NOT_POWER_OF_2(_weight);                   \
+                BUILD_BUG_ON(!__builtin_constant_p(_precision));        \
+                BUILD_BUG_ON(!__builtin_constant_p(_weight_rcp));       \
+                BUILD_BUG_ON((_precision) > 30);                        \
+                BUILD_BUG_ON_NOT_POWER_OF_2(_weight_rcp);               \
                                                                         \
                 ACCESS_ONCE(e->internal) = internal ?                   \
-                        (((internal << weight) - internal) +            \
-                                (val << factor)) >> weight :            \
-                        (val << factor);                                \
+                        (((internal << weight_rcp) - internal) +        \
+                                (val << precision)) >> weight_rcp :     \
+                        (val << precision);                             \
         }
 
 #endif /* _LINUX_AVERAGE_H */
diff --git a/include/linux/mlx4/driver.h b/include/linux/mlx4/driver.h
index e965e5090d96..a858bcb6220b 100644
--- a/include/linux/mlx4/driver.h
+++ b/include/linux/mlx4/driver.h
@@ -109,7 +109,7 @@ static inline void mlx4_u64_to_mac(u8 *addr, u64 mac)
         int i;
 
         for (i = ETH_ALEN; i > 0; i--) {
-                addr[i - 1] = mac && 0xFF;
+                addr[i - 1] = mac & 0xFF;
                 mac >>= 8;
         }
 }
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index f40f0ab3847a..97456b2539e4 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -330,6 +330,7 @@ struct napi_struct {
 
 enum {
         NAPI_STATE_SCHED,       /* Poll is scheduled */
+        NAPI_STATE_MISSED,      /* reschedule a napi */
         NAPI_STATE_DISABLE,     /* Disable pending */
         NAPI_STATE_NPSVC,       /* Netpoll - don't dequeue from poll_list */
         NAPI_STATE_HASHED,      /* In NAPI hash (busy polling possible) */
@@ -338,12 +339,13 @@ enum {
 };
 
 enum {
-        NAPIF_STATE_SCHED        = (1UL << NAPI_STATE_SCHED),
-        NAPIF_STATE_DISABLE      = (1UL << NAPI_STATE_DISABLE),
-        NAPIF_STATE_NPSVC        = (1UL << NAPI_STATE_NPSVC),
-        NAPIF_STATE_HASHED       = (1UL << NAPI_STATE_HASHED),
-        NAPIF_STATE_NO_BUSY_POLL = (1UL << NAPI_STATE_NO_BUSY_POLL),
-        NAPIF_STATE_IN_BUSY_POLL = (1UL << NAPI_STATE_IN_BUSY_POLL),
+        NAPIF_STATE_SCHED        = BIT(NAPI_STATE_SCHED),
+        NAPIF_STATE_MISSED       = BIT(NAPI_STATE_MISSED),
+        NAPIF_STATE_DISABLE      = BIT(NAPI_STATE_DISABLE),
+        NAPIF_STATE_NPSVC        = BIT(NAPI_STATE_NPSVC),
+        NAPIF_STATE_HASHED       = BIT(NAPI_STATE_HASHED),
+        NAPIF_STATE_NO_BUSY_POLL = BIT(NAPI_STATE_NO_BUSY_POLL),
+        NAPIF_STATE_IN_BUSY_POLL = BIT(NAPI_STATE_IN_BUSY_POLL),
 };
 
 enum gro_result {
@@ -414,20 +416,7 @@ static inline bool napi_disable_pending(struct napi_struct *n)
         return test_bit(NAPI_STATE_DISABLE, &n->state);
 }
 
-/**
- *      napi_schedule_prep - check if NAPI can be scheduled
- *      @n: NAPI context
- *
- * Test if NAPI routine is already running, and if not mark
- * it as running.  This is used as a condition variable to
- * insure only one NAPI poll instance runs.  We also make
- * sure there is no pending NAPI disable.
- */
-static inline bool napi_schedule_prep(struct napi_struct *n)
-{
-        return !napi_disable_pending(n) &&
-                !test_and_set_bit(NAPI_STATE_SCHED, &n->state);
-}
+bool napi_schedule_prep(struct napi_struct *n);
 
 /**
  *      napi_schedule - schedule NAPI poll