Commit eb48e9fc authored by Gwendal Grignou's avatar Gwendal Grignou Committed by Martin K. Petersen
Browse files

scsi: ufs: core: sysfs: Prevent div by zero 



Prevent a division by 0 when monitoring is not enabled.

Fixes: 1d8613a2 ("scsi: ufs: core: Introduce HBA performance monitor sysfs nodes")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarGwendal Grignou <gwendal@chromium.org>
Link: https://lore.kernel.org/r/20241120062522.917157-1-gwendal@chromium.org


Reviewed-by: default avatarCan Guo <quic_cang@quicinc.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 35002a8e

drivers/ufs/core/ufs-sysfs.c

+6 −0
Original line number Diff line number Diff line
@@ -670,6 +670,9 @@ static ssize_t read_req_latency_avg_show(struct device *dev, 
	struct ufs_hba *hba = dev_get_drvdata(dev);

	struct ufs_hba_monitor *m = &hba->monitor;



	if (!m->nr_req[READ])

		return sysfs_emit(buf, "0\n");



	return sysfs_emit(buf, "%llu\n", div_u64(ktime_to_us(m->lat_sum[READ]),

						 m->nr_req[READ]));

}
@@ -737,6 +740,9 @@ static ssize_t write_req_latency_avg_show(struct device *dev, 
	struct ufs_hba *hba = dev_get_drvdata(dev);

	struct ufs_hba_monitor *m = &hba->monitor;



	if (!m->nr_req[WRITE])

		return sysfs_emit(buf, "0\n");



	return sysfs_emit(buf, "%llu\n", div_u64(ktime_to_us(m->lat_sum[WRITE]),

						 m->nr_req[WRITE]));

}