Re: [PATCH 13/26] locking: Add non-fatal spin lock assert

[Peter Hurley <peter@hurleysoftware.com>]

Hi Peter,

On 09/03/2014 05:27 AM, Peter Zijlstra wrote:
> On Tue, Sep 02, 2014 at 05:39:22PM -0400, Peter Hurley wrote:
>> Provide method for non-essential or non-critical code to warn of
>> invariant errors.
>>
>> CC: Ingo Molnar <mingo@kernel.org>
>> CC: Peter Zijlstra <peterz@infradead.org>
>> CC: Thomas Gleixner <tglx@linutronix.de>
>> Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
>> ---
>>  include/linux/spinlock.h         | 1 +
>>  include/linux/spinlock_api_smp.h | 1 +
>>  include/linux/spinlock_api_up.h  | 1 +
>>  3 files changed, 3 insertions(+)
>>
>> diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
>> index 3f2867f..8a9aaf1 100644
>> --- a/include/linux/spinlock.h
>> +++ b/include/linux/spinlock.h
>> @@ -394,6 +394,7 @@ static inline int spin_can_lock(spinlock_t *lock)
>>  }
>>  
>>  #define assert_spin_locked(lock)	assert_raw_spin_locked(&(lock)->rlock)
>> +#define warn_not_spin_locked(lock)	warn_not_raw_spin_locked(&(lock)->rlock)
>>  
>>  /*
>>   * Pull the atomic_t declaration:
>> diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
>> index 42dfab8..0ddd499 100644
>> --- a/include/linux/spinlock_api_smp.h
>> +++ b/include/linux/spinlock_api_smp.h
>> @@ -18,6 +18,7 @@
>>  int in_lock_functions(unsigned long addr);
>>  
>>  #define assert_raw_spin_locked(x)	BUG_ON(!raw_spin_is_locked(x))
>> +#define warn_not_raw_spin_locked(x)	WARN_ON_ONCE(!raw_spin_is_locked(x))
> 
> No we should remove assert_spin_locked() not add to it. Use
> lockdep_assert_held() instead.

I probably should have been more descriptive in the changelog: this
is not for a test configuration, but rather, an assertion in an
exported api.

Regards,
Peter Hurley