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scsi: mpi3mr: A performance fix

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Commit 0c52310f26 ("hrtimer: Ignore slack time for RT tasks in
schedule_hrtimeout_range()") effectivelly shortens a sleep in a polling
function in the driver.  That is causing a performance regression as the
new value of just 2us is too low, in certain tests the perf drop is ~30%.
Fix this by adjusting the sleep to 20us (close to the previous value).

Reported-by: Jan Jurca <jjurca@redhat.com>
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Link: https://lore.kernel.org/r/20240903144729.37218-1-thenzl@redhat.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Tomas Henzl 2024-09-03 16:47:29 +02:00 committed by Martin K. Petersen
parent 0c40f079f1
commit 24d7071d96
2 changed files with 2 additions and 2 deletions
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2
drivers/scsi/mpi3mr/mpi3mr.h
View file

@ -178,7 +178,7 @@ extern atomic64_t event_counter;
#define MPI3MR_DEFAULT_SDEV_QD 32
/* Definitions for Threaded IRQ poll*/
#define MPI3MR_IRQ_POLL_SLEEP 2
#define MPI3MR_IRQ_POLL_SLEEP 20
#define MPI3MR_IRQ_POLL_TRIGGER_IOCOUNT 8
/* Definitions for the controller security status*/

2
drivers/scsi/mpi3mr/mpi3mr_fw.c
View file

@ -728,7 +728,7 @@ static irqreturn_t mpi3mr_isr_poll(int irq, void *privdata)
mpi3mr_process_op_reply_q(mrioc,
intr_info->op_reply_q);
usleep_range(MPI3MR_IRQ_POLL_SLEEP, 10 * MPI3MR_IRQ_POLL_SLEEP);
usleep_range(MPI3MR_IRQ_POLL_SLEEP, MPI3MR_IRQ_POLL_SLEEP + 1);
} while (atomic_read(&intr_info->op_reply_q->pend_ios) &&
(num_op_reply < mrioc->max_host_ios));