From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri, 05 Sep 2008 11:46:30 +0200
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] [PATCH 2/9] Switch to handle-based fast mutex
 owners	- v2
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: xenomai-core <xenomai@xenomai.org>

Gilles Chanteperdrix wrote:
> Jan Kiszka wrote:
>> @@ -230,18 +230,20 @@ static inline int mutex_save_count(xnthr
>>  
>>  	mutex = shadow->mutex;
>>  
>> -	if (clear_claimed(xnarch_atomic_intptr_get(mutex->owner)) != cur)
>> +	if (clear_claimed(xnarch_atomic_get(mutex->owner)) !=
>> +	    xnthread_handle(cur))
>>  		return EPERM;
>>  
>>  	*count_ptr = shadow->lockcnt;
>>  
>> -	if (likely(xnarch_atomic_intptr_cmpxchg(mutex->owner, cur, NULL) == cur))
>> +	if (likely(xnarch_atomic_cmpxchg(mutex->owner, cur, XN_NO_HANDLE) ==
>> +		   xnthread_handle(cur)))
>>  		return 0;
>>  
>>  	owner = xnsynch_wakeup_one_sleeper(&mutex->synchbase);
>> -	xnarch_atomic_intptr_set
>> -		(mutex->owner,
>> -		 set_claimed(owner,xnsynch_nsleepers(&mutex->synchbase)));
>> +	xnarch_atomic_set(mutex->owner,
>> +			  set_claimed(xnthread_handle(owner),
>> +				      xnsynch_nsleepers(&mutex->synchbase)));
> 
> Ok. Can we avoid xnthread_handle() everywhere by storing its result in a
> local variable and reusing this local variable, here and in the other
> functions where xnthread_handle is used multiple times ?

True for 'cur' here (will fix), but the other case have already been
optimized as far as possible (i.e. within the respective scope).

Jan

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