Re: [PATCH RFC -rt] Allow rcutorture to handle synchronize_sched()

[Josh Triplett]

On Fri, 2007-08-03 at 11:44 -0700, Paul E. McKenney wrote:
> The rcutorture module uses a random-number generator that periodically
> calls get_random_bytes() to add entropy.  This random-number generator
> is invoked from within the RCU read-side critical section, which, in the
> case of the synchronize_sched() variant of RCU, has preeemption disabled.
> Unfortunately, get_random_bytes() ends up acquiring normal spinlocks,
> which can block in -rt, resulting in very large numbers of "scheduling
> while atomic" messages.
> 
> This patch takes a very crude approach, simply substituting the time
> of day for get_random_bytes().
> 
> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>

Acked-by: Josh Triplett <josh@xxxxxxxxxx>


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