Changeset 4759 for lm-sensors/branches/lm-sensors-3.0.0/lib/sysfs.c

Timestamp:

09/05/07 10:19:09 (6 years ago)

Author:

khali

Message:

Renumber the features linearly, so that feature number N is at
position N in the array. This allows for O(1) look-ups, as opposed
to O(N) before. This makes sensors_lookup_feature_nr() 2.4 times
faster in my real-world tests, resulting in a 6% performance boost
on average in the runtime part of "sensors".

Files:

• lm-sensors/branches/lm-sensors-3.0.0/lib/sysfs.c (modified) (1 diff)

lm-sensors/branches/lm-sensors-3.0.0/lib/sysfs.c

@@ -176 +176 @@
                         dyn_features[fnum] = features[i];
                         fnum++;
+                }
+        }
+
+        /* Renumber the features linearly, so that feature number N is at
+           position N in the array. This allows for O(1) look-ups. */
+        for (i = 0; i < fnum; i++) {
+                int j, old;
+
+                old = dyn_features[i].data.number;
+                dyn_features[i].data.number = i;
+                for (j = i + 1;
+                     j < fnum && dyn_features[j].data.mapping != SENSORS_NO_MAPPING;
+                     j++) {
+                        if (dyn_features[j].data.mapping == old)
+                                dyn_features[j].data.mapping = i;
                 }
         }