From 96170421ea0b77779faf9e14499a14910e88de33 Mon Sep 17 00:00:00 2001 From: Christian Ehrhardt Date: Fri, 27 Feb 2015 08:20:46 -0700 Subject: [PATCH] fio: fix cycles_start build issue MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit There is an issue introduced with "commit 73df3e07 gettime: offset CPU cycle counter by initial value". For architectures which define ARCH_CPU_CLOCK_CYCLES_PER_USEC (currently only s390) this causes a build error gettime.c:174:11: error: ‘cycles_start’ undeclared (first use in this function) if (t < cycles_start && !cycles_wrap) To make sure variables and code are only compiled in the same cases I added a clock definition called ARCH_CPU_CLOCK_WRAPS. We could merge ARCH_CPU_CLOCK_WRAPS and the existing ARCH_CPU_CLOCK_CYCLES_PER_USEC into one if you prefer, so far nobody else uses it. To avoid cluttering all architecture headers I enabled it by default in arch-generic.h, so any arch not needing the wrap handling can undef ARCH_CPU_CLOCK_WRAPS later in their headers. Signed-off-by: Christian Ehrhardt Signed-off-by: Jens Axboe --- arch/arch-s390.h | 1 + arch/arch.h | 2 ++ gettime.c | 6 ++++++ 3 files changed, 9 insertions(+) diff --git a/arch/arch-s390.h b/arch/arch-s390.h index 169282b9..cc7a1d10 100644 --- a/arch/arch-s390.h +++ b/arch/arch-s390.h @@ -40,6 +40,7 @@ static inline unsigned long long get_cpu_clock(void) #define ARCH_CPU_CLOCK_CYCLES_PER_USEC 1 #define ARCH_HAVE_CPU_CLOCK +#undef ARCH_CPU_CLOCK_WRAPS #define ARCH_HAVE_INIT extern int tsc_reliable; diff --git a/arch/arch.h b/arch/arch.h index 0075f73d..5671b9a0 100644 --- a/arch/arch.h +++ b/arch/arch.h @@ -30,6 +30,8 @@ enum { extern unsigned long arch_flags; +#define ARCH_CPU_CLOCK_WRAPS + #if defined(__i386__) #include "arch-x86.h" #elif defined(__x86_64__) diff --git a/gettime.c b/gettime.c index 6863ce3f..d1c8eb97 100644 --- a/gettime.c +++ b/gettime.c @@ -17,6 +17,8 @@ static unsigned long cycles_per_usec; static unsigned long inv_cycles_per_usec; static uint64_t max_cycles_for_mult; +#endif +#ifdef ARCH_CPU_CLOCK_WRAPS static unsigned long long cycles_start, cycles_wrap; #endif int tsc_reliable = 0; @@ -171,6 +173,7 @@ static void __fio_gettime(struct timeval *tp) #endif t = get_cpu_clock(); +#ifdef ARCH_CPU_CLOCK_WRAPS if (t < cycles_start && !cycles_wrap) cycles_wrap = 1; else if (cycles_wrap && t >= cycles_start && !tv->warned) { @@ -179,6 +182,7 @@ static void __fio_gettime(struct timeval *tp) } t -= cycles_start; +#endif tv->last_cycles = t; tv->last_tv_valid = 1; #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC @@ -311,8 +315,10 @@ 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); +#ifdef ARCH_CPU_CLOCK_WRAPS cycles_start = get_cpu_clock(); dprint(FD_TIME, "cycles_start=%llu\n", cycles_start); +#endif return 0; } #else -- 2.25.1