[SCSI] fnic: FC stat param seconds_since_last_reset not getting updated

Code to reset fc_host statistics.
echo 1 > /sys/class/fc_host/hostX/statistics/reset_statistics clears fc_host stats,
the code also issues command to fnic firmware to clear vnic stats.

Signed-off-by: Narsimhulu Musini <[e-mail]>
Signed-off-by: Hiral Patel <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/fnic/fnic.h

···
 	FNIC_CHECK_LOGGING(FNIC_ISR_LOGGING,			\
 			 shost_printk(kern_level, host, fmt, ##args);)
 
+#define FNIC_MAIN_NOTE(kern_level, host, fmt, args...)          \
+	shost_printk(kern_level, host, fmt, ##args)
+
 extern const char *fnic_state_str[];
 
 enum fnic_intx_intr_index {
···
 
 	struct vnic_stats *stats;
 	unsigned long stats_time;	/* time of stats update */
+	unsigned long stats_reset_time; /* time of stats reset */
 	struct vnic_nic_cfg *nic_cfg;
 	char name[IFNAMSIZ];
 	struct timer_list notify_timer; /* used for MSI interrupts */
···
 	return ((fnic->state_flags & st_flags) == st_flags);
 }
 void __fnic_set_state_flags(struct fnic *, unsigned long, unsigned long);
+void fnic_dump_fchost_stats(struct Scsi_Host *, struct fc_host_statistics *);
 #endif /* _FNIC_H_ */

drivers/scsi/fnic/fnic_main.c

···
 static void fnic_get_host_speed(struct Scsi_Host *shost);
 static struct scsi_transport_template *fnic_fc_transport;
 static struct fc_host_statistics *fnic_get_stats(struct Scsi_Host *);
+static void fnic_reset_host_stats(struct Scsi_Host *);
 
 static struct fc_function_template fnic_fc_functions = {
 
···
 	.set_rport_dev_loss_tmo = fnic_set_rport_dev_loss_tmo,
 	.issue_fc_host_lip = fnic_reset,
 	.get_fc_host_stats = fnic_get_stats,
+	.reset_fc_host_stats = fnic_reset_host_stats,
 	.dd_fcrport_size = sizeof(struct fc_rport_libfc_priv),
 	.terminate_rport_io = fnic_terminate_rport_io,
 	.bsg_request = fc_lport_bsg_request,
···
 	stats->error_frames = vs->tx.tx_errors + vs->rx.rx_errors;
 	stats->dumped_frames = vs->tx.tx_drops + vs->rx.rx_drop;
 	stats->invalid_crc_count = vs->rx.rx_crc_errors;
-	stats->seconds_since_last_reset = (jiffies - lp->boot_time) / HZ;
+	stats->seconds_since_last_reset =
+			(jiffies - fnic->stats_reset_time) / HZ;
 	stats->fcp_input_megabytes = div_u64(fnic->fcp_input_bytes, 1000000);
 	stats->fcp_output_megabytes = div_u64(fnic->fcp_output_bytes, 1000000);
 
 	return stats;
+}
+
+/*
+ * fnic_dump_fchost_stats
+ * note : dumps fc_statistics into system logs
+ */
+void fnic_dump_fchost_stats(struct Scsi_Host *host,
+				struct fc_host_statistics *stats)
+{
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: seconds since last reset = %llu\n",
+			stats->seconds_since_last_reset);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: tx frames		= %llu\n",
+			stats->tx_frames);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: tx words		= %llu\n",
+			stats->tx_words);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: rx frames		= %llu\n",
+			stats->rx_frames);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: rx words		= %llu\n",
+			stats->rx_words);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: lip count		= %llu\n",
+			stats->lip_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: nos count		= %llu\n",
+			stats->nos_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: error frames		= %llu\n",
+			stats->error_frames);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: dumped frames	= %llu\n",
+			stats->dumped_frames);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: link failure count	= %llu\n",
+			stats->link_failure_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: loss of sync count	= %llu\n",
+			stats->loss_of_sync_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: loss of signal count	= %llu\n",
+			stats->loss_of_signal_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: prim seq protocol err count = %llu\n",
+			stats->prim_seq_protocol_err_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: invalid tx word count= %llu\n",
+			stats->invalid_tx_word_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: invalid crc count	= %llu\n",
+			stats->invalid_crc_count);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: fcp input requests	= %llu\n",
+			stats->fcp_input_requests);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: fcp output requests	= %llu\n",
+			stats->fcp_output_requests);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: fcp control requests	= %llu\n",
+			stats->fcp_control_requests);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: fcp input megabytes	= %llu\n",
+			stats->fcp_input_megabytes);
+	FNIC_MAIN_NOTE(KERN_NOTICE, host,
+			"fnic: fcp output megabytes	= %llu\n",
+			stats->fcp_output_megabytes);
+	return;
+}
+
+/*
+ * fnic_reset_host_stats : clears host stats
+ * note : called when reset_statistics set under sysfs dir
+ */
+static void fnic_reset_host_stats(struct Scsi_Host *host)
+{
+	int ret;
+	struct fc_lport *lp = shost_priv(host);
+	struct fnic *fnic = lport_priv(lp);
+	struct fc_host_statistics *stats;
+	unsigned long flags;
+
+	/* dump current stats, before clearing them */
+	stats = fnic_get_stats(host);
+	fnic_dump_fchost_stats(host, stats);
+
+	spin_lock_irqsave(&fnic->fnic_lock, flags);
+	ret = vnic_dev_stats_clear(fnic->vdev);
+	spin_unlock_irqrestore(&fnic->fnic_lock, flags);
+
+	if (ret) {
+		FNIC_MAIN_DBG(KERN_DEBUG, fnic->lport->host,
+				"fnic: Reset vnic stats failed"
+				" 0x%x", ret);
+		return;
+	}
+	fnic->stats_reset_time = jiffies;
+	memset(stats, 0, sizeof(*stats));
+
+	return;
 }
 
 void fnic_log_q_error(struct fnic *fnic)
···
 	}
 
 	fc_lport_init_stats(lp);
+	fnic->stats_reset_time = jiffies;
 
 	fc_lport_config(lp);