gettime: fix compile warning for !ARCH_HAVE_CPU_CLOCK

[fio.git] / gettime.c

diff --git a/gettime.c b/gettime.c
index 7e3e2e5b4375724dcb826c2c34523b994b0d3034..172b4782b722fed95da4aadd456716cfdabae9eb 100644 (file)
--- a/gettime.c
+++ b/gettime.c
@@ -17,6 +17,7 @@
 static unsigned long cycles_per_usec;
 static unsigned long inv_cycles_per_usec;
 static uint64_t max_cycles_for_mult;
+static unsigned long long cycles_start, cycles_wrap;
 #endif
 int tsc_reliable = 0;
 
@@ -25,11 +26,13 @@ struct tv_valid {
        int last_tv_valid;
        int warned;
 };
+#ifdef ARCH_HAVE_CPU_CLOCK
 #ifdef CONFIG_TLS_THREAD
 static __thread struct tv_valid static_tv_valid;
 #else
 static pthread_key_t tv_tls_key;
 #endif
+#endif
 
 enum fio_cs fio_clock_source = FIO_PREFERRED_CLOCK_SOURCE;
 int fio_clock_source_set = 0;
@@ -136,14 +139,6 @@ static int fill_clock_gettime(struct timespec *ts)
 
 static void __fio_gettime(struct timeval *tp)
 {
-       struct tv_valid *tv;
-
-#ifdef CONFIG_TLS_THREAD
-       tv = &static_tv_valid;
-#else
-       tv = pthread_getspecific(tv_tls_key);
-#endif
-
        switch (fio_clock_source) {
 #ifdef CONFIG_GETTIMEOFDAY
        case CS_GTOD:
@@ -167,14 +162,23 @@ static void __fio_gettime(struct timeval *tp)
 #ifdef ARCH_HAVE_CPU_CLOCK
        case CS_CPUCLOCK: {
                uint64_t usecs, t;
+               struct tv_valid *tv;
+
+#ifdef CONFIG_TLS_THREAD
+               tv = &static_tv_valid;
+#else
+               tv = pthread_getspecific(tv_tls_key);
+#endif
 
                t = get_cpu_clock();
-               if (t < tv->last_cycles && tv->last_tv_valid &&
-                   !tv->warned) {
-                       log_err("fio: CPU clock going back in time\n");
+               if (t < cycles_start && !cycles_wrap)
+                       cycles_wrap = 1;
+               else if (cycles_wrap && t >= cycles_start && !tv->warned) {
+                       log_err("fio: double CPU clock wrap\n");
                        tv->warned = 1;
                }
 
+               t -= cycles_start;
                tv->last_cycles = t;
                tv->last_tv_valid = 1;
 #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC
@@ -299,6 +303,8 @@ static int calibrate_cpu_clock(void)
        inv_cycles_per_usec = 16777216UL / cycles_per_usec;
        max_cycles_for_mult = ~0ULL / inv_cycles_per_usec;
        dprint(FD_TIME, "inv_cycles_per_usec=%lu\n", inv_cycles_per_usec);
+       cycles_start = get_cpu_clock();
+       dprint(FD_TIME, "cycles_start=%llu\n", cycles_start);
        return 0;
 }
 #else