diff options
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_txrx.c | 22 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_txrx.h | 1 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 22 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/i40evf/i40e_txrx.h | 1 |
4 files changed, 36 insertions, 10 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index f00f233092e9..1519dfb851d0 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -961,11 +961,25 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) enum i40e_latency_range new_latency_range = rc->latency_range; u32 new_itr = rc->itr; int bytes_per_int; - int usecs; + unsigned int usecs, estimated_usecs; if (rc->total_packets == 0 || !rc->itr) return false; + usecs = (rc->itr << 1) * ITR_COUNTDOWN_START; + bytes_per_int = rc->total_bytes / usecs; + + /* The calculations in this algorithm depend on interrupts actually + * firing at the ITR rate. This may not happen if the packet rate is + * really low, or if we've been napi polling. Check to make sure + * that's not the case before we continue. + */ + estimated_usecs = jiffies_to_usecs(jiffies - rc->last_itr_update); + if (estimated_usecs > usecs) { + new_latency_range = I40E_LOW_LATENCY; + goto reset_latency; + } + /* simple throttlerate management * 0-10MB/s lowest (50000 ints/s) * 10-20MB/s low (20000 ints/s) @@ -977,9 +991,6 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) * are in 2 usec increments in the ITR registers, and make sure * to use the smoothed values that the countdown timer gives us. */ - usecs = (rc->itr << 1) * ITR_COUNTDOWN_START; - bytes_per_int = rc->total_bytes / usecs; - switch (new_latency_range) { case I40E_LOWEST_LATENCY: if (bytes_per_int > 10) @@ -998,6 +1009,7 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) break; } +reset_latency: rc->latency_range = new_latency_range; switch (new_latency_range) { @@ -1016,12 +1028,12 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) rc->total_bytes = 0; rc->total_packets = 0; + rc->last_itr_update = jiffies; if (new_itr != rc->itr) { rc->itr = new_itr; return true; } - return false; } diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h index e6456e8a899c..2f848bc5e391 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h @@ -461,6 +461,7 @@ struct i40e_ring_container { struct i40e_ring *ring; unsigned int total_bytes; /* total bytes processed this int */ unsigned int total_packets; /* total packets processed this int */ + unsigned long last_itr_update; /* jiffies of last ITR update */ u16 count; enum i40e_latency_range latency_range; u16 itr; diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index 2f7d9f4a6746..c32c62462c84 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -359,11 +359,25 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) enum i40e_latency_range new_latency_range = rc->latency_range; u32 new_itr = rc->itr; int bytes_per_int; - int usecs; + unsigned int usecs, estimated_usecs; if (rc->total_packets == 0 || !rc->itr) return false; + usecs = (rc->itr << 1) * ITR_COUNTDOWN_START; + bytes_per_int = rc->total_bytes / usecs; + + /* The calculations in this algorithm depend on interrupts actually + * firing at the ITR rate. This may not happen if the packet rate is + * really low, or if we've been napi polling. Check to make sure + * that's not the case before we continue. + */ + estimated_usecs = jiffies_to_usecs(jiffies - rc->last_itr_update); + if (estimated_usecs > usecs) { + new_latency_range = I40E_LOW_LATENCY; + goto reset_latency; + } + /* simple throttlerate management * 0-10MB/s lowest (50000 ints/s) * 10-20MB/s low (20000 ints/s) @@ -375,9 +389,6 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) * are in 2 usec increments in the ITR registers, and make sure * to use the smoothed values that the countdown timer gives us. */ - usecs = (rc->itr << 1) * ITR_COUNTDOWN_START; - bytes_per_int = rc->total_bytes / usecs; - switch (new_latency_range) { case I40E_LOWEST_LATENCY: if (bytes_per_int > 10) @@ -396,6 +407,7 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) break; } +reset_latency: rc->latency_range = new_latency_range; switch (new_latency_range) { @@ -414,12 +426,12 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) rc->total_bytes = 0; rc->total_packets = 0; + rc->last_itr_update = jiffies; if (new_itr != rc->itr) { rc->itr = new_itr; return true; } - return false; } diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.h b/drivers/net/ethernet/intel/i40evf/i40e_txrx.h index fb506c9f5a6e..0d9f98bc07bd 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.h +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.h @@ -432,6 +432,7 @@ struct i40e_ring_container { struct i40e_ring *ring; unsigned int total_bytes; /* total bytes processed this int */ unsigned int total_packets; /* total packets processed this int */ + unsigned long last_itr_update; /* jiffies of last ITR update */ u16 count; enum i40e_latency_range latency_range; u16 itr; |