scsi: lpfc: Rework MIB Rx Monitor debug info logic

The kernel test robot reported the following sparse warning:

arch/arm64/include/asm/cmpxchg.h:88:1: sparse: sparse: cast truncates
   bits from constant value (369 becomes 69)

On arm64, atomic_xchg only works on 8-bit byte fields.  Thus, the macro
usage of LPFC_RXMONITOR_TABLE_IN_USE can be unintentionally truncated
leading to all logic involving the LPFC_RXMONITOR_TABLE_IN_USE macro to not
work properly.

Replace the Rx Table atomic_t indexing logic with a new
lpfc_rx_info_monitor structure that holds a circular ring buffer.  For
locking semantics, a spinlock_t is used.

Link: https://lore.kernel.org/r/20220819011736.14141-4-jsmart2021@gmail.com
Fixes: 17b27ac59224 ("scsi: lpfc: Add rx monitoring statistics")
Cc: <stable@vger.kernel.org> # v5.15+
Co-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 23 insertions, 60 deletions

diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index c69c5a0979ec..460295b7c9fe 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -5569,38 +5569,12 @@ lpfc_async_link_speed_to_read_top(struct lpfc_hba *phba, uint8_t speed_code)
 void
 lpfc_cgn_dump_rxmonitor(struct lpfc_hba *phba)
 {
-	struct rxtable_entry *entry;
-	int cnt = 0, head, tail, last, start;
-
-	head = atomic_read(&phba->rxtable_idx_head);
-	tail = atomic_read(&phba->rxtable_idx_tail);
-	if (!phba->rxtable || head == tail) {
-		lpfc_printf_log(phba, KERN_ERR, LOG_CGN_MGMT,
-				"4411 Rxtable is empty\n");
-		return;
-	}
-	last = tail;
-	start = head;
-
-	/* Display the last LPFC_MAX_RXMONITOR_DUMP entries from the rxtable */
-	while (start != last) {
-		if (start)
-			start--;
-		else
-			start = LPFC_MAX_RXMONITOR_ENTRY - 1;
-		entry = &phba->rxtable[start];
+	if (!phba->rx_monitor) {
 		lpfc_printf_log(phba, KERN_INFO, LOG_CGN_MGMT,
-				"4410 %02d: MBPI %lld Xmit %lld Cmpl %lld "
-				"Lat %lld ASz %lld Info %02d BWUtil %d "
-				"Int %d slot %d\n",
-				cnt, entry->max_bytes_per_interval,
-				entry->total_bytes, entry->rcv_bytes,
-				entry->avg_io_latency, entry->avg_io_size,
-				entry->cmf_info, entry->timer_utilization,
-				entry->timer_interval, start);
-		cnt++;
-		if (cnt >= LPFC_MAX_RXMONITOR_DUMP)
-			return;
+				"4411 Rx Monitor Info is empty.\n");
+	} else {
+		lpfc_rx_monitor_report(phba, phba->rx_monitor, NULL, 0,
+				       LPFC_MAX_RXMONITOR_DUMP);
 	}
 }
 
@@ -6007,9 +5981,8 @@ lpfc_cmf_timer(struct hrtimer *timer)
 {
 	struct lpfc_hba *phba = container_of(timer, struct lpfc_hba,
 					     cmf_timer);
-	struct rxtable_entry *entry;
+	struct rx_info_entry entry;
 	uint32_t io_cnt;
-	uint32_t head, tail;
 	uint32_t busy, max_read;
 	uint64_t total, rcv, lat, mbpi, extra, cnt;
 	int timer_interval = LPFC_CMF_INTERVAL;
@@ -6129,40 +6102,30 @@ lpfc_cmf_timer(struct hrtimer *timer)
 	}
 
 	/* Save rxmonitor information for debug */
-	if (phba->rxtable) {
-		head = atomic_xchg(&phba->rxtable_idx_head,
-				   LPFC_RXMONITOR_TABLE_IN_USE);
-		entry = &phba->rxtable[head];
-		entry->total_bytes = total;
-		entry->cmf_bytes = total + extra;
-		entry->rcv_bytes = rcv;
-		entry->cmf_busy = busy;
-		entry->cmf_info = phba->cmf_active_info;
+	if (phba->rx_monitor) {
+		entry.total_bytes = total;
+		entry.cmf_bytes = total + extra;
+		entry.rcv_bytes = rcv;
+		entry.cmf_busy = busy;
+		entry.cmf_info = phba->cmf_active_info;
 		if (io_cnt) {
-			entry->avg_io_latency = div_u64(lat, io_cnt);
-			entry->avg_io_size = div_u64(rcv, io_cnt);
+			entry.avg_io_latency = div_u64(lat, io_cnt);
+			entry.avg_io_size = div_u64(rcv, io_cnt);
 		} else {
-			entry->avg_io_latency = 0;
-			entry->avg_io_size = 0;
+			entry.avg_io_latency = 0;
+			entry.avg_io_size = 0;
 		}
-		entry->max_read_cnt = max_read;
-		entry->io_cnt = io_cnt;
-		entry->max_bytes_per_interval = mbpi;
+		entry.max_read_cnt = max_read;
+		entry.io_cnt = io_cnt;
+		entry.max_bytes_per_interval = mbpi;
 		if (phba->cmf_active_mode == LPFC_CFG_MANAGED)
-			entry->timer_utilization = phba->cmf_last_ts;
+			entry.timer_utilization = phba->cmf_last_ts;
 		else
-			entry->timer_utilization = ms;
-		entry->timer_interval = ms;
+			entry.timer_utilization = ms;
+		entry.timer_interval = ms;
 		phba->cmf_last_ts = 0;
 
-		/* Increment rxtable index */
-		head = (head + 1) % LPFC_MAX_RXMONITOR_ENTRY;
-		tail = atomic_read(&phba->rxtable_idx_tail);
-		if (head == tail) {
-			tail = (tail + 1) % LPFC_MAX_RXMONITOR_ENTRY;
-			atomic_set(&phba->rxtable_idx_tail, tail);
-		}
-		atomic_set(&phba->rxtable_idx_head, head);
+		lpfc_rx_monitor_record(phba->rx_monitor, &entry);
 	}
 
 	if (phba->cmf_active_mode == LPFC_CFG_MONITOR) {