in_cpu: normalize per-process CPU stats by number of cores (#2543)

Signed-off-by: yang-padawan <25978390+yang-padawan@users.noreply.github.com>

Author: matej-staron

plugins/in_cpu/cpu.c

@@ -333,16 +333,17 @@ struct cpu_snapshot *snapshot_pid_percent(struct cpu_stats *cstats,
     sum_pre = (snap_pre->v_user + snap_pre->v_system);
     sum_now = (snap_now->v_user + snap_now->v_system);
 
-    snap_now->p_cpu = CPU_METRIC_USAGE(sum_pre, sum_now, ctx);
+    snap_now->p_cpu = CPU_METRIC_SYS_AVERAGE(sum_pre, sum_now, ctx);
 
     /* User space CPU% */
-    snap_now->p_user = CPU_METRIC_USAGE(snap_pre->v_user, snap_now->v_user,
-                                        ctx);
+    snap_now->p_user = CPU_METRIC_SYS_AVERAGE(snap_pre->v_user,
+                                              snap_now->v_user,
+                                              ctx);
 
     /* Kernel space CPU% */
-    snap_now->p_system = CPU_METRIC_USAGE(snap_pre->v_system,
-                                          snap_now->v_system,
-                                          ctx);
+    snap_now->p_system = CPU_METRIC_SYS_AVERAGE(snap_pre->v_system,
+                                                snap_now->v_system,
+                                                ctx);
 
 #ifdef FLB_TRACE
     flb_trace("cpu[pid=%i] all=%s%f%s user=%s%f%s system=%s%f%s",

plugins/in_cpu/cpu.h

@@ -131,21 +131,4 @@ static inline double CPU_METRIC_USAGE(unsigned long pre, unsigned long now,
     return total;
 }
 
-/* Returns the CPU % utilization of a given CPU core */
-static inline double CPU_METRIC_PID_USAGE(unsigned long pre, unsigned long now,
-                                          struct flb_cpu *ctx)
-{
-    double diff;
-    double total = 0;
-
-    if (pre == now) {
-        return 0.0;
-    }
-
-    diff = ULL_ABS(now, pre);
-    total = 100.0 * ((diff / ctx->cpu_ticks) / (ctx->interval_sec + 1e-9*ctx->interval_nsec));
-
-    return total;
-}
-
 #endif