Add read delay and function to calculate average_cpu_usage

Author: zielinsky

analyzer.c

@@ -1,21 +1,41 @@
 #include "analyzer.h"
 #include "cputracker.h"
 
+
+unsigned long average_cpu_usage(struct proc_stat prev, struct proc_stat next){
+  unsigned long prev_idle = prev.idle + prev.iowait;
+  unsigned long idle = next.idle + next.iowait;
+
+  unsigned long prev_non_idle = prev.user + prev.nice + prev.system + prev.irq + prev.softirq + prev.steal;
+  unsigned long non_idle = next.user + next.nice + next.system + next.irq + next.softirq + next.steal;
+
+  unsigned long prev_total = prev_idle + prev_non_idle;
+  unsigned long total = idle + non_idle;
+
+  total -= prev_total;
+  idle -= prev_idle;
+
+  return (total-idle)*100/total;  
+}
+
+
 void *analyzer() {
+  struct proc_stat *prev = malloc(g_nproc*sizeof(struct proc_stat));
+  struct proc_stat *stats = NULL;
   while (1) {
     sem_wait(&g_filledSpaceSemaphore);
+
     pthread_mutex_lock(&g_bufferMutex);
 
-    struct proc_stat *stats = get_item();
+    stats = get_item_from_buffer();
+    for(int i = 0; i < g_nproc; i++){
+      printf("%lu ", average_cpu_usage(prev[i], stats[i]));
+      prev[i] = stats[i];
+    }
 
+    printf("\n");
     pthread_mutex_unlock(&g_bufferMutex);
-    sem_post(&g_leftSpaceSemaphore);
 
-    for (int i = 0; i < g_nproc; i++) {
-      printf("%s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n", stats[i].name,
-             stats[i].user, stats[i].nice, stats[i].system, stats[i].idle,
-             stats[i].iowait, stats[i].irq, stats[i].softirq, stats[i].steal,
-             stats[i].guest, stats[i].guest_nice);
-    }
+    sem_post(&g_leftSpaceSemaphore);
   }
 }

analyzer.h

@@ -3,4 +3,5 @@
 #include "cputracker.h"
 
 void *analyzer();
+unsigned long average_cpu_usage(struct proc_stat prev, struct proc_stat next);
 #endif

cputracker.c

@@ -22,7 +22,7 @@ int get_semaphore_value(sem_t *sem) {
   return sval;
 }
 
-struct proc_stat *get_item() {
+struct proc_stat *get_item_from_buffer() {
   int index = get_semaphore_value(&g_filledSpaceSemaphore);
   return g_buffer[index];
 }

cputracker.h

@@ -41,5 +41,5 @@ extern sem_t g_leftSpaceSemaphore;
 
 int get_nproc(int *nproc);
 int get_semaphore_value(sem_t *sem);
-struct proc_stat *get_item();
+struct proc_stat *get_item_from_buffer();
 #endif

reader.c

@@ -22,13 +22,15 @@ int get_proc_stats(struct proc_stat *stats) {
 }
 
 void *reader() {
+  struct proc_stat *stats = NULL;
   while (1) {
 
     sem_wait(&g_leftSpaceSemaphore);
 
     pthread_mutex_lock(&g_bufferMutex);
 
-    struct proc_stat *stats = get_item();
+    stats = get_item_from_buffer();
+    
     if (get_proc_stats(stats) == -1) {
       pthread_mutex_unlock(&g_bufferMutex);
       continue;
@@ -37,5 +39,6 @@ void *reader() {
     pthread_mutex_unlock(&g_bufferMutex);
 
     sem_post(&g_filledSpaceSemaphore);
+    usleep(READ_DELAY);
   }
 }

reader.h

@@ -2,6 +2,8 @@
 #define READER_H
 #include "cputracker.h"
 
+#define READ_DELAY 30000
+
 int get_proc_stats(struct proc_stat *stats);
 void *reader();