cpu plugin: Refactor the AIX code. Handle increasing / decreasing number of CPUs...

diff --git a/src/cpu.c b/src/cpu.c
index 7a6bba3..f89882a 100644 (file)
--- a/src/cpu.c
+++ b/src/cpu.c
@@ -140,11 +140,8 @@ static int maxcpu;
 /* #endif  HAVE_LIBSTATGRAB */
 
 #elif defined(HAVE_PERFSTAT)
-static perfstat_cpu_t *perfcpu;
-static int numcpu;
-static int pnumcpu;
-static u_longlong_t *cpu_total;
-static u_longlong_t *pcpu_total;
+static u_longlong_t *cpu_total_prev = NULL;
+static int numcpu_prev = 0;
 #endif /* HAVE_PERFSTAT */
 
 static int init (void)
@@ -562,49 +559,61 @@ static int cpu_read (void)
 /* #endif HAVE_LIBSTATGRAB */
 
 #elif defined(HAVE_PERFSTAT)
+       perfstat_cpu_t *perfcpu = NULL;
+       u_longlong_t *cpu_total = NULL;
        perfstat_id_t id;
        perfstat_cpu_t *pcpu;
-       u_longlong_t *cpu_swap;
-       int i, cpus;
+       u_longlong_t *temp;
+       int numcpu;
+       int i;
 
-       numcpu =  perfstat_cpu(NULL, NULL, sizeof(perfstat_cpu_t), 0);
-       if(numcpu == -1)
+       numcpu = perfstat_cpu (/* id = */ NULL, /* out */ NULL,
+                       /* size = */ sizeof(perfstat_cpu_t), /* nmemb = */ 0);
+       if (numcpu < 0)
        {
                char errbuf[1024];
-               WARNING ("cpu plugin: perfstat_cpu: %s",
+               WARNING ("cpu plugin: perfstat_cpu failed: %s",
                        sstrerror (errno, errbuf, sizeof (errbuf)));
                return (-1);
        }
-       
-       if (pnumcpu != numcpu || perfcpu == NULL) 
-       {
-               if (perfcpu != NULL) 
-                       free(perfcpu);
-               perfcpu = malloc(numcpu * sizeof(perfstat_cpu_t));
 
-               if (cpu_total != NULL)
-                       free(cpu_total);
-               cpu_total = (u_longlong_t *)calloc(numcpu, sizeof(u_longlong_t));
-
-               if (pcpu_total != NULL)
-                       free(pcpu_total);
-               pcpu_total = (u_longlong_t *)calloc(numcpu, sizeof(u_longlong_t));
+       /* Allocate required buffers */
+       perfcpu = calloc(numcpu, sizeof (*perfcpu));
+       cpu_total = calloc (numcpu, sizeof (*cpu_total));
+       if ((perfcpu == NULL) || (cpu_total == NULL))
+       {
+               sfree (perfcpu);
+               sfree (cpu_total);
+               ERROR ("cpu plugin: calloc failed.");
+               return (ENOMEM);
        }
-       pnumcpu = numcpu;
-
-       id.name[0] = '\0';
-       if ((cpus = perfstat_cpu(&id, perfcpu, sizeof(perfstat_cpu_t), numcpu)) < 0)
+       
+       /* Actually query the data. */
+       memset (&id, 0, sizeof (id));
+       i = perfstat_cpu (/* id = */ &id, /* out */ perfcpu,
+                       /* size = */ sizeof (*perfcpu), /* nmemb = */ numcpu);
+       if (i < 0)
        {
                char errbuf[1024];
-               WARNING ("cpu plugin: perfstat_cpu: %s",
+               WARNING ("cpu plugin: perfstat_cpu failed: %s",
                        sstrerror (errno, errbuf, sizeof (errbuf)));
                return (-1);
        }
+       else if (i < numcpu)
+       {
+               /* The number of CPUs has decreased since determining "numcpu".
+                * Upate the variable. If the number of CPUs *increases*
+                * (i > numcpu), ignore that. We'll get them on the next
+                * iteration. */
+               numcpu = i;
+       }
 
-       for (i = 0, pcpu = perfcpu; i < cpus; i++, pcpu++)
+       for (i = 0, pcpu = perfcpu; i < numcpu; i++, pcpu++)
        {
+               /* If all the counters stay the same, the CPU is offline and we
+                * don't dispatch any values. */
                cpu_total[i] = pcpu->idle + pcpu->sys + pcpu->user + pcpu->wait;
-               if (cpu_total[i] == pcpu_total[i])
+               if ((i < numcpu_prev) && (cpu_total[i] == cpu_total_prev[i]))
                        continue;
 
                submit (i, "idle",   (counter_t) pcpu->idle);
@@ -613,13 +622,19 @@ static int cpu_read (void)
                submit (i, "wait",   (counter_t) pcpu->wait);
        }
 
-       cpu_swap = pcpu_total;
-       pcpu_total = cpu_total;
-       cpu_total = cpu_swap;
+       /* Free the old data */
+       sfree (cpu_total_prev);
+
+       /* Keep the current data */
+       cpu_total_prev = cpu_total;
+       numcpu_prev = numcpu;
+
+       /* Free performance buffer */
+       sfree (perfcpu);
 #endif /* HAVE_PERFSTAT */
 
        return (0);
-}
+} /* int cpu_read */
 
 void module_register (void)
 {