projects / ipfire-2.x.git / blame
| Commit | Line | Data |
|---|---|---|
| 82094b55 AF |
1 | From: Gerald Schaefer <geraldsc@de.ibm.com> |
| 2 | Subject: [PATCH] introduce get_clock_monotonic | |
| 3 | References: bnc#532063,LTC#55526 | |
| 4 | ||
| 5 | From: Heiko Carstens <heiko.carstens@de.ibm.com> | |
| 6 | ||
| 7 | Introduce get_clock_monotonic() function which can be used to get a | |
| 8 | (fast) timestamp. Resolution is the same as for get_clock(). The | |
| 9 | only difference is that the timestamps are monotonic and don't jump | |
| 10 | backward or forward. | |
| 11 | ||
| 12 | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> | |
| 13 | Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> | |
| 14 | ||
| 15 | Acked-by: John Jolly <jjolly@suse.de> | |
| 16 | --- | |
| 17 | ||
| 18 | arch/s390/include/asm/timex.h | 16 ++++++++++++++++ | |
| 19 | arch/s390/kernel/time.c | 3 ++- | |
| 20 | 2 files changed, 18 insertions(+), 1 deletion(-) | |
| 21 | ||
| 22 | Index: linux-sles11/arch/s390/include/asm/timex.h | |
| 23 | =================================================================== | |
| 24 | --- linux-sles11.orig/arch/s390/include/asm/timex.h | |
| 25 | +++ linux-sles11/arch/s390/include/asm/timex.h | |
| 26 | @@ -85,4 +85,20 @@ int get_sync_clock(unsigned long long *c | |
| 27 | void init_cpu_timer(void); | |
| 28 | unsigned long long monotonic_clock(void); | |
| 29 | ||
| 30 | +extern u64 jiffies_timer_cc; | |
| 31 | + | |
| 32 | +/** | |
| 33 | + * get_clock_monotonic - returns current time in clock rate units | |
| 34 | + * | |
| 35 | + * The caller must ensure that preemption is disabled. | |
| 36 | + * The clock and sched_clock_base get changed via stop_machine. | |
| 37 | + * Therefore preemption must be disabled when calling this | |
| 38 | + * function, otherwise the returned value is not guaranteed to | |
| 39 | + * be monotonic. | |
| 40 | + */ | |
| 41 | +static inline unsigned long long get_clock_monotonic(void) | |
| 42 | +{ | |
| 43 | + return get_clock_xt() - jiffies_timer_cc; | |
| 44 | +} | |
| 45 | + | |
| 46 | #endif | |
| 47 | Index: linux-sles11/arch/s390/kernel/time.c | |
| 48 | =================================================================== | |
| 49 | --- linux-sles11.orig/arch/s390/kernel/time.c | |
| 50 | +++ linux-sles11/arch/s390/kernel/time.c | |
| 51 | @@ -63,7 +63,8 @@ | |
| 52 | ||
| 53 | static ext_int_info_t ext_int_info_cc; | |
| 54 | static ext_int_info_t ext_int_etr_cc; | |
| 55 | -static u64 jiffies_timer_cc; | |
| 56 | +u64 jiffies_timer_cc; | |
| 57 | +EXPORT_SYMBOL(jiffies_timer_cc); | |
| 58 | ||
| 59 | static DEFINE_PER_CPU(struct clock_event_device, comparators); | |
| 60 |