Changeset cc36562b in mainline

Timestamp:

2018-08-25T19:06:27Z (6 years ago)

Author:

Jakub Jermar <jakub@…>

Children:

72df613

Parents:

02f547f

Message:

Provide a single clock() implementation in libc

Also attempt to fix the implementation to return microseconds (clocks)
rather than processor cycles.

Location:

uspace/lib

Files:

• c/generic/time.c (modified) (2 diffs)
• c/include/time.h (modified) (1 diff)
• posix/include/posix/time.h (modified) (2 diffs)
• posix/src/time.c (modified) (2 diffs)

uspace/lib/c/generic/time.c

@@ -50 +50 @@
 #include <loc.h>
 #include <device/clock_dev.h>
+#include <stats.h>
 
 #define ASCTIME_BUF_LEN  26
@@ -70 +71 @@
 static async_sess_t *clock_conn = NULL;
 
-/** Return processor time used by the program.
- *
- * @return -1  The processor time used is not available in this implementation.
+/**
+ * Get CPU time used since the process invocation.
+ *
+ * @return Consumed microseconds by this process or -1 if not available.
  */
 clock_t clock(void)
 {
-        return (clock_t) -1;
+        static_assert(CLOCKS_PER_SEC == 1000000);
+
+        size_t count;
+        stats_cpu_t *cpu_stats = stats_get_cpus(&count);
+        if (!cpu_stats)
+                return (clock_t) -1;
+
+        clock_t total_usecs = -1;
+        if (cpu_stats) {
+                stats_task_t *task_stats = stats_get_task(task_get_id());
+                if (task_stats) {
+                        total_usecs = (clock_t) (task_stats->kcycles +
+                            task_stats->ucycles) / cpu_stats->frequency_mhz;
+                        free(task_stats);
+                }
+                free(cpu_stats);
+        }
+
+        return total_usecs;
 }
 

uspace/lib/c/include/time.h

@@ -45 +45 @@
 #include <_bits/NULL.h>
 
-#define CLOCKS_PER_SEC  ((clock_t) 1)
+#define CLOCKS_PER_SEC  ((clock_t) 1000000)
 
 #define TIME_UTC        1

uspace/lib/posix/include/posix/time.h

@@ -42 +42 @@
 
 #include "libc/time.h"
-
-#undef CLOCKS_PER_SEC
-#define CLOCKS_PER_SEC (1000000L)
 
 #ifndef __locale_t_defined
@@ -102 +99 @@
     const struct timespec *rqtp, struct timespec *rmtp);
 
-/* CPU Time */
-extern clock_t clock(void);
-
 #endif  // POSIX_TIME_H_
 

uspace/lib/posix/src/time.c

@@ -49 +49 @@
 #include "libc/malloc.h"
 #include "libc/task.h"
-#include "libc/stats.h"
 #include "libc/stddef.h"
 #include "libc/time.h"
@@ -311 +310 @@
 }
 
-/**
- * Get CPU time used since the process invocation.
- *
- * @return Consumed CPU cycles by this process or -1 if not available.
- */
-clock_t clock(void)
-{
-        clock_t total_cycles = -1;
-        stats_task_t *task_stats = stats_get_task(task_get_id());
-        if (task_stats) {
-                total_cycles = (clock_t) (task_stats->kcycles +
-                    task_stats->ucycles);
-                free(task_stats);
-                task_stats = 0;
-        }
-
-        return total_cycles;
-}
-
 int gettimeofday(struct timeval *tv, void *tz)
 {