This patch conditionalizes some output from perfc_printall(), thus making relevant...

legible. It additionally changes the formatting so that trailing spaces are avoided.

Also changing the type of some variables from plain int to unsigned int, as that is yielding more efficient code on
x86-64 (signed 32-bit array indices require explicit sign extension, whereas in most cases an extra copy can be avoided
when the index type is unsigned, since all 32-bit operations already zero-extend their results).

Signed-off-by: Jan Beulich <jbeulich@novell.com>

diff --git a/xen/common/perfc.c b/xen/common/perfc.c
index 7e54c980fe9a2b682b241b56cb09392591187a38..df63c1042bbd1d17593394deaf96821febaff979 100644 (file)
--- a/xen/common/perfc.c
+++ b/xen/common/perfc.c
@@ -37,7 +37,7 @@ struct perfcounter perfcounters;
 
 void perfc_printall(unsigned char key)
 {
-    int i, j, sum;
+    unsigned int i, j, sum;
     s_time_t now = NOW();
     atomic_t *counters = (atomic_t *)&perfcounters;
 
@@ -59,22 +59,28 @@ void perfc_printall(unsigned char key)
             sum = 0;
             for_each_online_cpu ( j )
                 sum += atomic_read(&counters[j]);
-            printk("TOTAL[%10d]  ", sum);
-            for_each_online_cpu ( j )
-                printk("CPU%02d[%10d]  ", j, atomic_read(&counters[j]));
+            printk("TOTAL[%10u]", sum);
+            if (sum)
+            {
+                for_each_online_cpu ( j )
+                    printk("  CPU%02d[%10d]", j, atomic_read(&counters[j]));
+            }
             counters += NR_CPUS;
             break;
         case TYPE_ARRAY:
         case TYPE_S_ARRAY:
             for ( j = sum = 0; j < perfc_info[i].nr_elements; j++ )
                 sum += atomic_read(&counters[j]);
-            printk("TOTAL[%10d]  ", sum);
+            printk("TOTAL[%10u]", sum);
 #ifdef PERF_ARRAYS
-            for ( j = 0; j < perfc_info[i].nr_elements; j++ )
+            if (sum)
             {
-                if ( (j != 0) && ((j % 4) == 0) )
-                    printk("\n                   ");
-                printk("ARR%02d[%10d]  ", j, atomic_read(&counters[j]));
+                for ( j = 0; j < perfc_info[i].nr_elements; j++ )
+                {
+                    if ( (j % 4) == 0 )
+                        printk("\n                 ");
+                    printk("  ARR%02d[%10d]", j, atomic_read(&counters[j]));
+                }
             }
 #endif
             counters += j;
@@ -90,7 +96,7 @@ void perfc_printall(unsigned char key)
 
 void perfc_reset(unsigned char key)
 {
-    int i, j;
+    unsigned int i, j;
     s_time_t now = NOW();
     atomic_t *counters = (atomic_t *)&perfcounters;