sar: No need to init previous iteration structure when a device has been

registered again

Simplify code a bit: Don't reset previous iteration's statistics when a
known device has been registered again, since this is already done when
stats are displayed.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>

diff --git a/sa_common.c b/sa_common.c
index c0c01437173e3dcf535175492af8970082adec1d..254faf2b6606a913be3a8531acbcf42b2d0b3b9b 100644 (file)
--- a/sa_common.c
+++ b/sa_common.c
@@ -604,8 +604,11 @@ void print_report_hdr(unsigned int flags, struct tm *rectime,
  *
  * RETURNS:
  * Position of current network interface in array of sample statistics used
- * as reference, or -1 if it is a new interface (it was not present in array
- * of stats used as reference).
+ * as reference.
+ * -1 if it is a new interface (it was not present in array of stats used
+ * as reference).
+ * -2 if it is a known interface but which has been unregistered then
+ * registered again on the interval.
  *
  * Note: A newly registered interface, if it is supernumerary, may make the
  * last interface in the array going out of the list. Yet an interface going
@@ -676,14 +679,12 @@ int check_net_dev_reg(struct activity *a, int curr, int ref, int pos)
                                        ovfw = TRUE;
                                }
 
-                               if (!ovfw) {
+                               if (!ovfw)
                                        /*
                                         * OK: assume here that the device was
                                         * actually unregistered.
                                         */
-                                       memset(sndp, 0, STATS_NET_DEV_SIZE);
-                                       strncpy(sndp->interface, sndc->interface, MAX_IFACE_LEN - 1);
-                               }
+                                       return -2;
                        }
                        return index;
                }
@@ -707,7 +708,10 @@ int check_net_dev_reg(struct activity *a, int curr, int ref, int pos)
  *
  * RETURNS:
  * Position of current network interface in array of sample statistics used
- * as reference, or -1 if it is a newly registered interface.
+ * as reference.
+ * -1 if it is a newly registered interface.
+ * -2 if it is a known interface but which has been unregistered then
+ * registered again on the interval.
  ***************************************************************************
  */
 int check_net_edev_reg(struct activity *a, int curr, int ref, int pos)
@@ -732,15 +736,13 @@ int check_net_edev_reg(struct activity *a, int curr, int ref, int pos)
                            (snedc->tx_carrier_errors < snedp->tx_carrier_errors) ||
                            (snedc->rx_frame_errors   < snedp->rx_frame_errors)   ||
                            (snedc->rx_fifo_errors    < snedp->rx_fifo_errors)    ||
-                           (snedc->tx_fifo_errors    < snedp->tx_fifo_errors)) {
-
+                           (snedc->tx_fifo_errors    < snedp->tx_fifo_errors))
                                /*
                                 * OK: assume here that the device was
                                 * actually unregistered.
                                 */
-                               memset(snedp, 0, STATS_NET_EDEV_SIZE);
-                               strncpy(snedp->interface, snedc->interface, MAX_IFACE_LEN - 1);
-                       }
+                               return -2;
+
                        return index;
                }
                index++;
@@ -763,7 +765,9 @@ int check_net_edev_reg(struct activity *a, int curr, int ref, int pos)
  *
  * RETURNS:
  * Position of current disk in array of sample statistics used as reference
- * or -1 if it is a newly registered device.
+ * -1 if it is a newly registered device.
+ * -2 if it is a known device but which has been unregistered then registered
+ * again on the interval.
  ***************************************************************************
  */
 int check_disk_reg(struct activity *a, int curr, int ref, int pos)
@@ -786,12 +790,10 @@ int check_disk_reg(struct activity *a, int curr, int ref, int pos)
                         */
                        if ((sdc->nr_ios < sdp->nr_ios) &&
                            (sdc->rd_sect < sdp->rd_sect) &&
-                           (sdc->wr_sect < sdp->wr_sect)) {
+                           (sdc->wr_sect < sdp->wr_sect))
+                               /* Same device registered again */
+                               return -2;
 
-                               memset(sdp, 0, STATS_DISK_SIZE);
-                               sdp->major = sdc->major;
-                               sdp->minor = sdc->minor;
-                       }
                        return index;
                }
                index++;