From: Paul E. McKenney <paulmck@kernel.org>
Date: Wed, 20 Jan 2021 16:21:47 +0000 (+0100)
Subject: kvfree_rcu: Use __GFP_NOMEMALLOC for single-argument kvfree_rcu()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=b01b405092b7940bd366053a27ed54a87c84e96a;p=linux.git

kvfree_rcu: Use __GFP_NOMEMALLOC for single-argument kvfree_rcu()

This commit applies the __GFP_NOMEMALLOC gfp flag to memory allocations
carried out by the single-argument variant of kvfree_rcu(), thus avoiding
this can-sleep code path from dipping into the emergency reserves.

Acked-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 1f8c980f41908..08b50441ebe8c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3519,7 +3519,7 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp,
 		if (!bnode && can_alloc) {
 			krc_this_cpu_unlock(*krcp, *flags);
 			bnode = (struct kvfree_rcu_bulk_data *)
-				__get_free_page(GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
+				__get_free_page(GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOMEMALLOC | __GFP_NOWARN);
 			*krcp = krc_this_cpu_lock(flags);
 		}