From 4b1cc7e7ca5715907d17619dcb49144db6efe1c9 Mon Sep 17 00:00:00 2001 From: John Lacombe Date: Thu, 21 Feb 2008 08:34:58 -0600 Subject: 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 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'drivers/infiniband/hw/nes/nes_hw.c') 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)); } -- cgit v1.2.3