From 3ce459cd684b7f18ca79838e62310ffdc930920b Mon Sep 17 00:00:00 2001 From: Mike Marciniszyn Date: Tue, 15 May 2018 18:31:24 -0700 Subject: IB/{rdmavt,hfi1}: Change hrtimer add to use pinned version Given we are dealing with nano-second level timers, when the timer pops, ensure it happens on the CPU which caused the timer to be set in the first place. This avoids excessive jitter from the desired expiration time by avoiding the cost of switching our context to another CPU that is cache cold for this given timer. Reviewed-by: Kaike Wan Signed-off-by: Mike Marciniszyn Signed-off-by: Dennis Dalessandro Signed-off-by: Doug Ledford --- drivers/infiniband/hw/hfi1/rc.c | 2 +- drivers/infiniband/sw/rdmavt/qp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/rc.c b/drivers/infiniband/hw/hfi1/rc.c index 79ee2b9e28c6..1a1a47ac53c6 100644 --- a/drivers/infiniband/hw/hfi1/rc.c +++ b/drivers/infiniband/hw/hfi1/rc.c @@ -2012,7 +2012,7 @@ void process_becn(struct hfi1_pportdata *ppd, u8 sl, u32 rlid, u32 lqpn, unsigned long nsec = 1024 * ccti_timer; hrtimer_start(&cca_timer->hrtimer, ns_to_ktime(nsec), - HRTIMER_MODE_REL); + HRTIMER_MODE_REL_PINNED); } spin_unlock_irqrestore(&ppd->cca_timer_lock, flags); diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index 6e9a351f45fb..40046135c509 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -2225,7 +2225,7 @@ void rvt_add_rnr_timer(struct rvt_qp *qp, u32 aeth) to = rvt_aeth_to_usec(aeth); trace_rvt_rnrnak_add(qp, to); hrtimer_start(&qp->s_rnr_timer, - ns_to_ktime(1000 * to), HRTIMER_MODE_REL); + ns_to_ktime(1000 * to), HRTIMER_MODE_REL_PINNED); } EXPORT_SYMBOL(rvt_add_rnr_timer); -- cgit v1.2.3