Fio 1.26.1

[fio.git] / gettime.c

diff --git a/gettime.c b/gettime.c
index 48aeb075b65e1c9182e41a3c1240603ebf968691..b1431f329bec2e3ef9e32439035d896e9f8545ca 100644 (file)
--- a/gettime.c
+++ b/gettime.c
@@ -1,26 +1,33 @@
 /*
- * Memory helpers
+ * Clock functions
  */
+
 #include <unistd.h>
 #include <sys/time.h>
 
 #include "fio.h"
-#include "os.h"
+#include "smalloc.h"
 
 #include "hash.h"
 
-static int clock_gettime_works = 1;
+static int clock_gettime_works;
+static struct timeval last_tv;
+static int last_tv_valid;
+
+static struct timeval *fio_tv;
+int fio_gtod_offload = 0;
+int fio_gtod_cpu = -1;
 
 #ifdef FIO_DEBUG_TIME
 
 #define HASH_BITS      8
 #define HASH_SIZE      (1 << HASH_BITS)
 
-static struct list_head hash[HASH_SIZE];
+static struct flist_head hash[HASH_SIZE];
 static int gtod_inited;
 
 struct gtod_log {
-       struct list_head list;
+       struct flist_head list;
        void *caller;
        unsigned long calls;
 };
@@ -28,10 +35,11 @@ struct gtod_log {
 static struct gtod_log *find_hash(void *caller)
 {
        unsigned long h = hash_ptr(caller, HASH_BITS);
-       struct list_head *entry;
+       struct flist_head *entry;
 
-       list_for_each(entry, &hash[h]) {
-               struct gtod_log *log = list_entry(entry, struct gtod_log, list);
+       flist_for_each(entry, &hash[h]) {
+               struct gtod_log *log = flist_entry(entry, struct gtod_log,
+                                                                       list);
 
                if (log->caller == caller)
                        return log;
@@ -48,12 +56,12 @@ static struct gtod_log *find_log(void *caller)
                unsigned long h;
 
                log = malloc(sizeof(*log));
-               INIT_LIST_HEAD(&log->list);
+               INIT_FLIST_HEAD(&log->list);
                log->caller = caller;
                log->calls = 0;
 
                h = hash_ptr(caller, HASH_BITS);
-               list_add_tail(&log->list, &hash[h]);
+               flist_add_tail(&log->list, &hash[h]);
        }
 
        return log;
@@ -74,13 +82,14 @@ static void fio_exit fio_dump_gtod(void)
        int i;
 
        for (i = 0; i < HASH_SIZE; i++) {
-               struct list_head *entry;
+               struct flist_head *entry;
                struct gtod_log *log;
 
-               list_for_each(entry, &hash[i]) {
-                       log = list_entry(entry, struct gtod_log, list);
+               flist_for_each(entry, &hash[i]) {
+                       log = flist_entry(entry, struct gtod_log, list);
 
-                       printf("function %p, calls %lu\n", log->caller, log->calls);
+                       printf("function %p, calls %lu\n", log->caller,
+                                                               log->calls);
                        total_calls += log->calls;
                }
        }
@@ -93,43 +102,65 @@ static void fio_init gtod_init(void)
        int i;
 
        for (i = 0; i < HASH_SIZE; i++)
-               INIT_LIST_HEAD(&hash[i]);
+               INIT_FLIST_HEAD(&hash[i]);
 
        gtod_inited = 1;
 }
 
 #endif /* FIO_DEBUG_TIME */
 
+#ifdef FIO_DEBUG_TIME
 void fio_gettime(struct timeval *tp, void *caller)
+#else
+void fio_gettime(struct timeval *tp, void fio_unused *caller)
+#endif
 {
 #ifdef FIO_DEBUG_TIME
        if (!caller)
                caller = __builtin_return_address(0);
 
        gtod_log_caller(caller);
-#else
-       caller = NULL;
 #endif
-repeat:
-       if (!clock_gettime_works)
+       if (fio_tv) {
+               memcpy(tp, fio_tv, sizeof(*tp));
+               return;
+       } else if (!clock_gettime_works) {
+gtod:
                gettimeofday(tp, NULL);
-       else {
+       } else {
                struct timespec ts;
 
                if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0) {
                        clock_gettime_works = 0;
-                       goto repeat;
+                       goto gtod;
                }
 
                tp->tv_sec = ts.tv_sec;
                tp->tv_usec = ts.tv_nsec / 1000;
        }
+
+       /*
+        * If Linux is using the tsc clock on non-synced processors,
+        * sometimes time can appear to drift backwards. Fix that up.
+        */
+       if (last_tv_valid) {
+               if (tp->tv_sec < last_tv.tv_sec)
+                       tp->tv_sec = last_tv.tv_sec;
+               else if (last_tv.tv_sec == tp->tv_sec &&
+                        tp->tv_usec < last_tv.tv_usec)
+                       tp->tv_usec = last_tv.tv_usec;
+       }
+       last_tv_valid = 1;
+       memcpy(&last_tv, tp, sizeof(*tp));
 }
 
-static void fio_init check_clock(void)
+void fio_gtod_init(void)
 {
-       struct timespec ts;
+       fio_tv = smalloc(sizeof(struct timeval));
+       assert(fio_tv);
+}
 
-       if (clock_getres(CLOCK_MONOTONIC, &ts) < 0)
-               clock_gettime_works = 0;
+void fio_gtod_update(void)
+{
+       gettimeofday(fio_tv, NULL);
 }