Re: [PATCH] Make treercu safe for suspend and resume

From: Ingo Molnar
Date: Mon Jan 05 2009 - 04:13:36 EST



* Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> wrote:

> Hello!
>
> Kudos to both Dhaval Giani and Jens Axboe for finding a bug in treercu
> that causes warnings after suspend-resume cycles in Dhaval's case and
> during stress tests in Jens's case. It would also probably cause failures
> if heavily stressed. The solution, ironically enough, is to revert to
> rcupreempt's code for initializing the dynticks state. And the patch
> even results in smaller code -- so what was I thinking???
>
> This is 2.6.29 material, given that people really do suspend and resume
> Linux these days. ;-)
>
> Located-by: Dhaval Giani <dhaval@xxxxxxxxxxxxxxxxxx>
> Located-by: Jens Axboe <jens.axboe@xxxxxxxxxx>
> Tested-by: Dhaval Giani <dhaval@xxxxxxxxxxxxxxxxxx>
> Tested-by: Jens Axboe <jens.axboe@xxxxxxxxxx>
> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
> ---
>
> rcutree.c | 12 ++++--------
> 1 file changed, 4 insertions(+), 8 deletions(-)

applied to tip/core/urgent, thanks guys!

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/