[SCSI] libfc: adds FCP failures stats

Adds stats to track FCP pkt and frame alloc
failure.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Acked-by : Robert Love <robert.w.love@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/libfc/fc_fcp.c

@@ -158,6 +158,9 @@ static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp)
 		fsp->timer.data = (unsigned long)fsp;
 		INIT_LIST_HEAD(&fsp->list);
 		spin_lock_init(&fsp->scsi_pkt_lock);
+	} else {
+		per_cpu_ptr(lport->stats, get_cpu())->FcpPktAllocFails++;
+		put_cpu();
 	}
 	return fsp;
 }
@@ -264,6 +267,9 @@ static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
 	if (!fsp->seq_ptr)
 		return -EINVAL;
 
+	per_cpu_ptr(fsp->lp->stats, get_cpu())->FcpPktAborts++;
+	put_cpu();
+
 	fsp->state |= FC_SRB_ABORT_PENDING;
 	return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
 }
@@ -420,6 +426,8 @@ static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport,
 	if (likely(fp))
 		return fp;
 
+	per_cpu_ptr(lport->stats, get_cpu())->FcpFrameAllocFails++;
+	put_cpu();
 	/* error case */
 	fc_fcp_can_queue_ramp_down(lport);
 	return NULL;

include/scsi/libfc.h

@@ -232,6 +232,9 @@ struct fc_rport_priv {
  * @RxWords:               Number of received words
  * @ErrorFrames:           Number of received error frames
  * @DumpedFrames:          Number of dumped frames
+ * @FcpPktAllocFails:      Number of fcp packet allocation failures
+ * @FcpPktAborts:          Number of fcp packet aborts
+ * @FcpFrameAllocFails:    Number of fcp frame allocation failures
  * @LinkFailureCount:      Number of link failures
  * @LossOfSignalCount:     Number for signal losses
  * @InvalidTxWordCount:    Number of invalid transmitted words
@@ -252,6 +255,9 @@ struct fc_stats {
 	u64		RxWords;
 	u64		ErrorFrames;
 	u64		DumpedFrames;
+	u64		FcpPktAllocFails;
+	u64		FcpPktAborts;
+	u64		FcpFrameAllocFails;
 	u64		LinkFailureCount;
 	u64		LossOfSignalCount;
 	u64		InvalidTxWordCount;