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Subject: [PATCH v1 6/6] xprtrdma: Prevent memory allocations from driving a
 reclaim
From:   Chuck Lever <chuck.lever@oracle.com>
To:     anna.schumaker@netapp.com
Cc:     linux-nfs@vger.kernel.org
Date:   Fri, 23 Sep 2022 09:06:37 -0400
Message-ID: <166393839700.1029362.13683786521054731422.stgit@morisot.1015granger.net>
In-Reply-To: <166393821144.1029362.9036806277307694311.stgit@morisot.1015granger.net>
References: <166393821144.1029362.9036806277307694311.stgit@morisot.1015granger.net>
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Many memory allocations that xprtrdma does can fail safely. Let's
use this fact to avoid some potential deadlocks: Replace GFP_KERNEL
with GFP flags that do not try hard to acquire memory.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/xprtrdma/verbs.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 7ca58cb65e27..44b87e4274b4 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -811,7 +811,7 @@ struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt,
 	struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
 	struct rpcrdma_req *req;
 
-	req = kzalloc(sizeof(*req), GFP_KERNEL);
+	req = kzalloc(sizeof(*req), XPRTRDMA_GFP_FLAGS);
 	if (req == NULL)
 		goto out1;
 
@@ -926,7 +926,7 @@ struct rpcrdma_rep *rpcrdma_rep_create(struct rpcrdma_xprt *r_xprt,
 	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
 	struct rpcrdma_rep *rep;
 
-	rep = kzalloc(sizeof(*rep), GFP_KERNEL);
+	rep = kzalloc(sizeof(*rep), XPRTRDMA_GFP_FLAGS);
 	if (rep == NULL)
 		goto out;
 
@@ -1236,10 +1236,10 @@ rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction)
 {
 	struct rpcrdma_regbuf *rb;
 
-	rb = kmalloc(sizeof(*rb), GFP_KERNEL);
+	rb = kmalloc(sizeof(*rb), XPRTRDMA_GFP_FLAGS);
 	if (!rb)
 		return NULL;
-	rb->rg_data = kmalloc(size, GFP_KERNEL);
+	rb->rg_data = kmalloc(size, XPRTRDMA_GFP_FLAGS);
 	if (!rb->rg_data) {
 		kfree(rb);
 		return NULL;