sfc: Implement adaptive IRQ moderation
Calculate a score for each 1000 IRQs:
- TX completions are worth 1 point
- RX completions are worth 4 if merged using LRO or 2 otherwise
Reduce moderation if the score is less than 10000, down to a minimum
of 5 us. Increase moderation if the score is more than 20000, up to
the specified maximum.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h
index b81fc72..e169e5d 100644
--- a/drivers/net/sfc/net_driver.h
+++ b/drivers/net/sfc/net_driver.h
@@ -336,6 +336,8 @@
* @eventq_read_ptr: Event queue read pointer
* @last_eventq_read_ptr: Last event queue read pointer value.
* @eventq_magic: Event queue magic value for driver-generated test events
+ * @irq_count: Number of IRQs since last adaptive moderation decision
+ * @irq_mod_score: IRQ moderation score
* @rx_alloc_level: Watermark based heuristic counter for pushing descriptors
* and diagnostic counters
* @rx_alloc_push_pages: RX allocation method currently in use for pushing
@@ -364,6 +366,9 @@
unsigned int last_eventq_read_ptr;
unsigned int eventq_magic;
+ unsigned int irq_count;
+ unsigned int irq_mod_score;
+
int rx_alloc_level;
int rx_alloc_push_pages;
@@ -703,6 +708,8 @@
* @membase: Memory BAR value
* @biu_lock: BIU (bus interface unit) lock
* @interrupt_mode: Interrupt mode
+ * @irq_rx_adaptive: Adaptive IRQ moderation enabled for RX event queues
+ * @irq_rx_moderation: IRQ moderation time for RX event queues
* @i2c_adap: I2C adapter
* @board_info: Board-level information
* @state: Device state flag. Serialised by the rtnl_lock.
@@ -784,6 +791,8 @@
void __iomem *membase;
spinlock_t biu_lock;
enum efx_int_mode interrupt_mode;
+ bool irq_rx_adaptive;
+ unsigned int irq_rx_moderation;
struct i2c_adapter i2c_adap;
struct efx_board board_info;