On Thu, Apr 20, 2023 at 01:06:27PM +0200, Uladzislau Rezki wrote: > On Tue, Apr 18, 2023 at 08:27:02PM +0800, Zqiang wrote: > > If the rcu_min_cached_objs is set to zero at boot params, the > > krcp->page_cache_work will not be triggered to fill page cache, > > and the put_cached_bnode() also does not fill page cache, this > > also means the krcp->bkvcache is always empty, so not need to > > acquire unnecessary krcp->lock to get page from krcp->bkvcache, > > this commit therefore make drain_page_cache() return directly if > > the rcu_min_cached_objs is zero. > > > > Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx> > > --- > > kernel/rcu/tree.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > > index 93faf9f5c58f..00620a2117de 100644 > > --- a/kernel/rcu/tree.c > > +++ b/kernel/rcu/tree.c > > @@ -2924,6 +2924,9 @@ drain_page_cache(struct kfree_rcu_cpu *krcp) > > struct llist_node *page_list, *pos, *n; > > int freed = 0; > > > > + if (!rcu_min_cached_objs) > > + return 0; > > + > > raw_spin_lock_irqsave(&krcp->lock, flags); > > page_list = llist_del_all(&krcp->bkvcache); > > WRITE_ONCE(krcp->nr_bkv_objs, 0); > > -- > > 2.32.0 > > > Reviewed-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx> Queued for further testing and review, thank you both! Thanx, Paul
