Patchwork rename get_clock_realtime

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Submitter Paolo Bonzini
Date Jan. 20, 2012, 11:05 a.m.
Message ID <1327057522-6590-1-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/137007/
State New
Headers show

Comments

Paolo Bonzini - Jan. 20, 2012, 11:05 a.m.
get_clock_realtime accesses the host_clock, not the rt_clock.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 qemu-timer.c |    2 +-
 qemu-timer.h |    4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)
Jan Kiszka - Jan. 20, 2012, 11:17 a.m.
On 2012-01-20 12:05, Paolo Bonzini wrote:
> get_clock_realtime accesses the host_clock, not the rt_clock.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  qemu-timer.c |    2 +-
>  qemu-timer.h |    4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/qemu-timer.c b/qemu-timer.c
> index cd026c6..4a14a6d 100644
> --- a/qemu-timer.c
> +++ b/qemu-timer.c
> @@ -436,7 +436,7 @@ int64_t qemu_get_clock_ns(QEMUClock *clock)
>              return cpu_get_clock();
>          }
>      case QEMU_CLOCK_HOST:
> -        now = get_clock_realtime();
> +        now = get_clock_host();
>          last = clock->last;
>          clock->last = now;
>          if (now < last) {
> diff --git a/qemu-timer.h b/qemu-timer.h
> index de17f3b..b180fca 100644
> --- a/qemu-timer.h
> +++ b/qemu-timer.h
> @@ -93,7 +93,7 @@ static inline int64_t get_ticks_per_sec(void)
>  }
>  
>  /* real time host monotonic timer */
> -static inline int64_t get_clock_realtime(void)
> +static inline int64_t get_clock_host(void)

It accesses the host realtime clock, so get_clock_host_realtime would be
optimal. In that light, the comment above should be fixed as well.

Jan

>  {
>      struct timeval tv;
>  
> @@ -131,7 +131,7 @@ static inline int64_t get_clock(void)
>      {
>          /* XXX: using gettimeofday leads to problems if the date
>             changes, so it should be avoided. */
> -        return get_clock_realtime();
> +        return get_clock_host();
>      }
>  }
>  #endif
Paolo Bonzini - Jan. 20, 2012, 11:26 a.m.
On 01/20/2012 12:17 PM, Jan Kiszka wrote:
> On 2012-01-20 12:05, Paolo Bonzini wrote:
>> get_clock_realtime accesses the host_clock, not the rt_clock.
>>
>> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
>> ---
>>   qemu-timer.c |    2 +-
>>   qemu-timer.h |    4 ++--
>>   2 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/qemu-timer.c b/qemu-timer.c
>> index cd026c6..4a14a6d 100644
>> --- a/qemu-timer.c
>> +++ b/qemu-timer.c
>> @@ -436,7 +436,7 @@ int64_t qemu_get_clock_ns(QEMUClock *clock)
>>               return cpu_get_clock();
>>           }
>>       case QEMU_CLOCK_HOST:
>> -        now = get_clock_realtime();
>> +        now = get_clock_host();
>>           last = clock->last;
>>           clock->last = now;
>>           if (now<  last) {
>> diff --git a/qemu-timer.h b/qemu-timer.h
>> index de17f3b..b180fca 100644
>> --- a/qemu-timer.h
>> +++ b/qemu-timer.h
>> @@ -93,7 +93,7 @@ static inline int64_t get_ticks_per_sec(void)
>>   }
>>
>>   /* real time host monotonic timer */
>> -static inline int64_t get_clock_realtime(void)
>> +static inline int64_t get_clock_host(void)
>
> It accesses the host realtime clock, so get_clock_host_realtime would be
> optimal. In that light, the comment above should be fixed as well.

Yeah, however, realtime is quite confusing because CLOCK_MONOTONIC is 
part of the "real-time clock API".  The code is much clearer than the 
comment, I'll remove it completely.  v2 on the way.

Paolo
Jan Kiszka - Jan. 20, 2012, 11:29 a.m.
On 2012-01-20 12:26, Paolo Bonzini wrote:
> On 01/20/2012 12:17 PM, Jan Kiszka wrote:
>> On 2012-01-20 12:05, Paolo Bonzini wrote:
>>> get_clock_realtime accesses the host_clock, not the rt_clock.
>>>
>>> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
>>> ---
>>>   qemu-timer.c |    2 +-
>>>   qemu-timer.h |    4 ++--
>>>   2 files changed, 3 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/qemu-timer.c b/qemu-timer.c
>>> index cd026c6..4a14a6d 100644
>>> --- a/qemu-timer.c
>>> +++ b/qemu-timer.c
>>> @@ -436,7 +436,7 @@ int64_t qemu_get_clock_ns(QEMUClock *clock)
>>>               return cpu_get_clock();
>>>           }
>>>       case QEMU_CLOCK_HOST:
>>> -        now = get_clock_realtime();
>>> +        now = get_clock_host();
>>>           last = clock->last;
>>>           clock->last = now;
>>>           if (now<  last) {
>>> diff --git a/qemu-timer.h b/qemu-timer.h
>>> index de17f3b..b180fca 100644
>>> --- a/qemu-timer.h
>>> +++ b/qemu-timer.h
>>> @@ -93,7 +93,7 @@ static inline int64_t get_ticks_per_sec(void)
>>>   }
>>>
>>>   /* real time host monotonic timer */
>>> -static inline int64_t get_clock_realtime(void)
>>> +static inline int64_t get_clock_host(void)
>>
>> It accesses the host realtime clock, so get_clock_host_realtime would be
>> optimal. In that light, the comment above should be fixed as well.
> 
> Yeah, however, realtime is quite confusing because CLOCK_MONOTONIC is 
> part of the "real-time clock API".  The code is much clearer than the 
> comment, I'll remove it completely.  v2 on the way.

There is CLOCK_MONOTONIC and CLOCK_REALTIME, and this function uses the
latter.

Jan
Paolo Bonzini - Jan. 20, 2012, 11:39 a.m.
On 01/20/2012 12:29 PM, Jan Kiszka wrote:
>> >  Yeah, however, realtime is quite confusing because CLOCK_MONOTONIC is
>> >  part of the "real-time clock API".  The code is much clearer than the
>> >  comment, I'll remove it completely.  v2 on the way.
> There is CLOCK_MONOTONIC and CLOCK_REALTIME, and this function uses the
> latter.

Actually it uses gettimeofday, but I see what you mean.

But QEMU_CLOCK_REALTIME and rt_clock refer to CLOCK_MONOTONIC and are 
_not_ read by get_clock_realtime.  This actually is what prompted me to 
rename get_clock_realtime (see commit message).

Paolo

Patch

diff --git a/qemu-timer.c b/qemu-timer.c
index cd026c6..4a14a6d 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -436,7 +436,7 @@  int64_t qemu_get_clock_ns(QEMUClock *clock)
             return cpu_get_clock();
         }
     case QEMU_CLOCK_HOST:
-        now = get_clock_realtime();
+        now = get_clock_host();
         last = clock->last;
         clock->last = now;
         if (now < last) {
diff --git a/qemu-timer.h b/qemu-timer.h
index de17f3b..b180fca 100644
--- a/qemu-timer.h
+++ b/qemu-timer.h
@@ -93,7 +93,7 @@  static inline int64_t get_ticks_per_sec(void)
 }
 
 /* real time host monotonic timer */
-static inline int64_t get_clock_realtime(void)
+static inline int64_t get_clock_host(void)
 {
     struct timeval tv;
 
@@ -131,7 +131,7 @@  static inline int64_t get_clock(void)
     {
         /* XXX: using gettimeofday leads to problems if the date
            changes, so it should be avoided. */
-        return get_clock_realtime();
+        return get_clock_host();
     }
 }
 #endif