From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
When in a low memory situation, we do want rpciod to kick off direct
reclaim in the case where that helps, however we don't want it looping
forever in mempool_alloc().
So first try allocating from the slab using GFP_KERNEL | __GFP_NORETRY,
and then fall back to a GFP_NOWAIT allocation from the mempool.
Ditto for rpc_alloc_task()
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
---
include/linux/sunrpc/sched.h | 1 +
net/sunrpc/sched.c | 21 ++++++++++++++-------
2 files changed, 15 insertions(+), 7 deletions(-)
diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h
index 56710f8056d3..1d7a3e51b795 100644
--- a/include/linux/sunrpc/sched.h
+++ b/include/linux/sunrpc/sched.h
@@ -262,6 +262,7 @@ void rpc_destroy_mempool(void);
extern struct workqueue_struct *rpciod_workqueue;
extern struct workqueue_struct *xprtiod_workqueue;
void rpc_prepare_task(struct rpc_task *task);
+gfp_t rpc_task_gfp_mask(void);
static inline int rpc_wait_for_completion_task(struct rpc_task *task)
{
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 7c8f87ebdbc0..d59a033820be 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -57,6 +57,13 @@ struct workqueue_struct *rpciod_workqueue __read_mostly;
struct workqueue_struct *xprtiod_workqueue __read_mostly;
EXPORT_SYMBOL_GPL(xprtiod_workqueue);
+gfp_t rpc_task_gfp_mask(void)
+{
+ if (current->flags & PF_WQ_WORKER)
+ return GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN;
+ return GFP_KERNEL;
+}
+
unsigned long
rpc_task_timeout(const struct rpc_task *task)
{
@@ -1030,15 +1037,15 @@ int rpc_malloc(struct rpc_task *task)
struct rpc_rqst *rqst = task->tk_rqstp;
size_t size = rqst->rq_callsize + rqst->rq_rcvsize;
struct rpc_buffer *buf;
- gfp_t gfp = GFP_KERNEL;
-
- if (RPC_IS_ASYNC(task))
- gfp = GFP_NOWAIT | __GFP_NOWARN;
+ gfp_t gfp = rpc_task_gfp_mask();
size += sizeof(struct rpc_buffer);
- if (size <= RPC_BUFFER_MAXSIZE)
- buf = mempool_alloc(rpc_buffer_mempool, gfp);
- else
+ if (size <= RPC_BUFFER_MAXSIZE) {
+ buf = kmem_cache_alloc(rpc_buffer_slabp, gfp);
+ /* Reach for the mempool if dynamic allocation fails */
+ if (!buf && RPC_IS_ASYNC(task))
+ buf = mempool_alloc(rpc_buffer_mempool, GFP_NOWAIT);
+ } else
buf = kmalloc(size, gfp);
if (!buf)
--
2.35.1
