From 4b1cc7e7ca5715907d17619dcb49144db6efe1c9 Mon Sep 17 00:00:00 2001 From: John Lacombe Date: Thu, 21 Feb 2008 08:34:58 -0600 Subject: [PATCH] RDMA/nes: Fix interrupt moderation low threshold Interrupt moderation low threshold value was incorrectly triggering, indicating that the threshold should be lowered. The impact was the timer was likely to become 40usecs and get stuck there. The biggest side effect was too many interrupts and nonoptimal performance. Signed-off-by: John Lacombe Signed-off-by: Glenn Streiff Signed-off-by: Roland Dreier --- drivers/infiniband/hw/nes/nes_hw.c | 13 +++++-------- drivers/infiniband/hw/nes/nes_hw.h | 2 +- 2 files changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/infiniband/hw/nes/nes_hw.c b/drivers/infiniband/hw/nes/nes_hw.c index 7c4c0fbf0abd..49e53e4c1ebe 100644 --- a/drivers/infiniband/hw/nes/nes_hw.c +++ b/drivers/infiniband/hw/nes/nes_hw.c @@ -156,15 +156,14 @@ static void nes_nic_tune_timer(struct nes_device *nesdev) spin_lock_irqsave(&nesadapter->periodic_timer_lock, flags); - if (shared_timer->cq_count_old < cq_count) { - if (cq_count > shared_timer->threshold_low) - shared_timer->cq_direction_downward=0; - } - if (shared_timer->cq_count_old >= cq_count) + if (shared_timer->cq_count_old <= cq_count) + shared_timer->cq_direction_downward = 0; + else shared_timer->cq_direction_downward++; shared_timer->cq_count_old = cq_count; if (shared_timer->cq_direction_downward > NES_NIC_CQ_DOWNWARD_TREND) { - if (cq_count <= shared_timer->threshold_low) { + if (cq_count <= shared_timer->threshold_low && + shared_timer->threshold_low > 4) { shared_timer->threshold_low = shared_timer->threshold_low/2; shared_timer->cq_direction_downward=0; nesdev->currcq_count = 0; @@ -1728,7 +1727,6 @@ int nes_napi_isr(struct nes_device *nesdev) nesdev->int_req &= ~NES_INT_TIMER; nes_write32(nesdev->regs+NES_INTF_INT_MASK, ~(nesdev->intf_int_req)); nes_write32(nesdev->regs+NES_INT_MASK, ~nesdev->int_req); - nesadapter->tune_timer.timer_in_use_old = 0; } nesdev->deepcq_count = 0; return 1; @@ -1867,7 +1865,6 @@ void nes_dpc(unsigned long param) nesdev->int_req &= ~NES_INT_TIMER; nes_write32(nesdev->regs + NES_INTF_INT_MASK, ~(nesdev->intf_int_req)); nes_write32(nesdev->regs+NES_INT_MASK, ~nesdev->int_req); - nesdev->nesadapter->tune_timer.timer_in_use_old = 0; } else { nes_write32(nesdev->regs+NES_INT_MASK, 0x0000ffff|(~nesdev->int_req)); } diff --git a/drivers/infiniband/hw/nes/nes_hw.h b/drivers/infiniband/hw/nes/nes_hw.h index 1e10df550c9e..b7e2844f096b 100644 --- a/drivers/infiniband/hw/nes/nes_hw.h +++ b/drivers/infiniband/hw/nes/nes_hw.h @@ -962,7 +962,7 @@ struct nes_arp_entry { #define DEFAULT_JUMBO_NES_QL_LOW 12 #define DEFAULT_JUMBO_NES_QL_TARGET 40 #define DEFAULT_JUMBO_NES_QL_HIGH 128 -#define NES_NIC_CQ_DOWNWARD_TREND 8 +#define NES_NIC_CQ_DOWNWARD_TREND 16 struct nes_hw_tune_timer { //u16 cq_count;