Re: [kvm-unit-tests PATCH v3 4/9] s390x: export the clock get_clock_ms() utility

Pierre Morel
2019-12-09T16:43:48Z

On 2019-12-09 12:49, David Hildenbrand wrote:
> On 09.12.19 12:42, Thomas Huth wrote:
>> On 06/12/2019 17.26, Pierre Morel wrote:
>>> To serve multiple times, the function get_clock_ms() is moved
>>> from intercept.c test to the new file asm/time.h.
>>>
>>> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
>>> Reviewed-by: David Hildenbrand <david@redhat.com>
>>> ---
>>> lib/s390x/asm/time.h | 27 +++++++++++++++++++++++++++
>>> s390x/intercept.c | 11 +----------
>>> 2 files changed, 28 insertions(+), 10 deletions(-)
>>> create mode 100644 lib/s390x/asm/time.h
>>>
>>> diff --git a/lib/s390x/asm/time.h b/lib/s390x/asm/time.h
>>> new file mode 100644
>>> index 0000000..b07ccbd
>>> --- /dev/null
>>> +++ b/lib/s390x/asm/time.h
>>> @@ -0,0 +1,27 @@
>>> +/*
>>> + * Clock utilities for s390
>>> + *
>>> + * Authors:
>>> + * Thomas Huth <thuth@redhat.com>
>>> + *
>>> + * Copied from the s390/intercept test by:
>>> + * Pierre Morel <pmorel@linux.ibm.com>
>>> + *
>>> + * This code is free software; you can redistribute it and/or modify it
>>> + * under the terms of the GNU General Public License version 2.
>>> + */
>>> +#ifndef _ASM_S390X_TIME_H_
>>> +#define _ASM_S390X_TIME_H_
>>> +
>>> +static inline uint64_t get_clock_ms(void)
>>> +{
>>> + uint64_t clk;
>>> +
>>> + asm volatile(" stck %0 " : : "Q"(clk) : "memory");
>>> +
>>> + /* Bit 51 is incrememented each microsecond */
>>> + return (clk >> (63 - 51)) / 1000;
>>> +}
>>> +
>>> +
>>
>> Please remove one of the two empty lines.
>>
>> With that cosmetic nit fixed:
>> Reviewed-by: Thomas Huth <thuth@redhat.com>
>>
> Reviewed-by: David Hildenbrand <david@redhat.com>
>

Thanks,
Pierre

--
Pierre Morel
IBM Lab Boeblingen