On Tue, Nov 12, 2013 at 04:29:56PM +0100, Peter Zijlstra wrote:
> On Tue, Nov 12, 2013 at 10:15:41AM -0500, Vivek Goyal wrote:
> > I see that we allocate per cpu stats but don't do any initializations.
> >
> > static void tg_stats_alloc_fn(struct work_struct *work)
> > {
> > static struct tg_stats_cpu *stats_cpu; /* this fn is non-reentrant
> > */
> > struct delayed_work *dwork = to_delayed_work(work);
> > bool empty = false;
> >
> > alloc_stats:
> > if (!stats_cpu) {
> > stats_cpu = alloc_percpu(struct tg_stats_cpu);
> > if (!stats_cpu) {
> > /* allocation failed, try again after some time */
> > schedule_delayed_work(dwork, msecs_to_jiffies(10));
> > return;
> > }
> > }
> >
> > spin_lock_irq(&tg_stats_alloc_lock);
>
> Absolutely!
>
> Something like this perhaps? Did I miss more blkg_[rw]stats? If I read
> the git grep output right, this was the last one.
Looks good to me.
This should be the last one. There are only two users of stats right
now. blk-throttle and cfq-iosched.
Thanks
Vivek
>
> ---
> block/blk-throttle.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/block/blk-throttle.c b/block/blk-throttle.c
> index 8331aba9426f..fd743d98c41d 100644
> --- a/block/blk-throttle.c
> +++ b/block/blk-throttle.c
> @@ -256,6 +256,12 @@ static struct throtl_data *sq_to_td(struct
> throtl_service_queue *sq)
> } \
> } while (0)
>
> +static void tg_stats_init(struct tg_stats_cpu *tg_stats)
> +{
> + blkg_rwstat_init(&tg_stats->service_bytes);
> + blkg_rwstat_init(&tg_stats->serviced);
> +}
> +
> /*
> * Worker for allocating per cpu stat for tgs. This is scheduled on the
> * system_wq once there are some groups on the alloc_list waiting for
> @@ -269,12 +275,16 @@ static void tg_stats_alloc_fn(struct work_struct *work)
>
> alloc_stats:
> if (!stats_cpu) {
> + int cpu;
> +
> stats_cpu = alloc_percpu(struct tg_stats_cpu);
> if (!stats_cpu) {
> /* allocation failed, try again after some time */
> schedule_delayed_work(dwork, msecs_to_jiffies(10));
> return;
> }
> + for_each_possible_cpu(cpu)
> + tg_stats_init(per_cpu(stats_cpu, cpu));
> }
>
> spin_lock_irq(&tg_stats_alloc_lock);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
