Changeset 944f2cab in mainline for kernel/generic/src/ps/load.c

Timestamp:

2010-03-31T09:30:04Z (14 years ago)

Author:

Stanislav Kozina <stanislav.kozina@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e257ae3

Parents:

3a10e34

Message:

ps -l echoes system load

File:

• kernel/generic/src/ps/load.c (modified) (2 diffs)

kernel/generic/src/ps/load.c

@@ -40 +40 @@
 #include <ps/load.h>
 #include <arch.h>
+#include <proc/scheduler.h>
+#include <config.h>
+#include <arch/types.h>
+#include <time/clock.h>
+#include <syscall/copy.h>
+
+static size_t get_running_count(void);
+
+size_t avenrun[3];
+
+#define FSHIFT   11             /* nr of bits of precision */
+#define FIXED_1  (1<<FSHIFT)    /* 1.0 as fixed-point */
+#define LOAD_FREQ 5             /* 5 sec intervals */
+#define EXP_1  1884             /* 1/exp(5sec/1min) as fixed-point */
+#define EXP_5  2014             /* 1/exp(5sec/5min) */
+#define EXP_15 2037             /* 1/exp(5sec/15min) */
+
+#define CALC_LOAD(load,exp,n) \
+        load *= exp; \
+        load += n*(FIXED_1-exp); \
+        load >>= FSHIFT;
+
+static inline unsigned long calc_load(size_t load, size_t exp, size_t active)
+{
+        load *= exp;
+        load += active * (FIXED_1 - exp);
+        return load >> FSHIFT;
+}
+
+static inline void calc_load_global(void)
+{
+        size_t active;
+
+        active = get_running_count();
+        active = active > 0 ? active * FIXED_1 : 0;
+        avenrun[0] = calc_load(avenrun[0], EXP_1, active);
+        avenrun[1] = calc_load(avenrun[1], EXP_5, active);
+        avenrun[2] = calc_load(avenrun[2], EXP_15, active);
+}
+
+static size_t get_running_count(void)
+{
+        size_t i;
+        size_t result = 0;
+        ipl_t ipl;
+
+        /* run queues should not change during reading */
+        ipl = interrupts_disable();
+
+        for (i = 0; i < config.cpu_active; ++i) {
+                cpu_t *cpu = &cpus[i];
+                int j;
+                for (j = 0; j < RQ_COUNT; ++j) {
+                        result += cpu->rq[j].n;
+                }
+        } 
+
+        interrupts_restore(ipl);
+        return result;
+}
 
 /** Load thread main function.
@@ -51 +111 @@
         /* Noone will thread_join us */
         thread_detach(THREAD);
+        avenrun[0] = 0;
+        avenrun[1] = 0;
+        avenrun[2] = 0;
 
         while (true) {
-                printf("load thread alive\n");
-                thread_sleep(5);
+                calc_load_global();
+                printf("Computed loads: 0x%x 0x%x 0x%x\n", avenrun[0], avenrun[1], avenrun[2]);
+                thread_sleep(LOAD_FREQ);
         }
+}
+
+int sys_ps_get_load(size_t *user_load)
+{
+        copy_to_uspace(user_load, avenrun, sizeof(avenrun));
+        return 0;
 }