Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 540eb1ee authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Martin K. Petersen
Browse files

scsi: libfc: fix seconds_since_last_reset calculation 



The fc_get_host_stats() function contains a complex conversion from
jiffies to timespec to seconds. As we try to get rid of uses of struct
timespec, we can clean this up and replace it with a simpler
computation.

Simply dividing the difference in jiffies by HZ is not only much more
efficient, it also avoids a problem that causes the
seconds_since_last_reset value to be incorrect if jiffies has overrun
since the 'boot_time' value was recorded.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Reviewed-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 0da21c44

drivers/scsi/libfc/fc_lport.c

+1 −4
Original line number Diff line number Diff line
@@ -301,7 +301,6 @@ struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *shost) 
{

	struct fc_host_statistics *fc_stats;

	struct fc_lport *lport = shost_priv(shost);

	struct timespec v0, v1;

	unsigned int cpu;

	u64 fcp_in_bytes = 0;

	u64 fcp_out_bytes = 0;
@@ -309,9 +308,7 @@ struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *shost) 
	fc_stats = &lport->host_stats;

	memset(fc_stats, 0, sizeof(struct fc_host_statistics));



	jiffies_to_timespec(jiffies, &v0);

	jiffies_to_timespec(lport->boot_time, &v1);

	fc_stats->seconds_since_last_reset = (v0.tv_sec - v1.tv_sec);

	fc_stats->seconds_since_last_reset = (lport->boot_time - jiffies) / HZ;



	for_each_possible_cpu(cpu) {

		struct fc_stats *stats;