On 9/16/20 12:08 PM, Manjunath Patil wrote:
RDS/IB tries to refill the recv buffer in softirq context using
GFP_NOWAIT flag. However alloc failure is handled by queueing a work to
refill the recv buffer with GFP_KERNEL flag. This means failure to
allocate with GFP_NOWAIT isn't fatal. Do not print the PAF warnings if
softirq context fails to refill the recv buffer, instead print a one
line warning once a day.
Signed-off-by: Manjunath Patil <manjunath.b.patil@xxxxxxxxxx>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@xxxxxxxxxx>
---
net/rds/ib_recv.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/net/rds/ib_recv.c b/net/rds/ib_recv.c
index 694d411dc72f..38d2894f6bb2 100644
--- a/net/rds/ib_recv.c
+++ b/net/rds/ib_recv.c
@@ -310,8 +310,8 @@ static int rds_ib_recv_refill_one(struct rds_connection *conn,
struct rds_ib_connection *ic = conn->c_transport_data;
struct ib_sge *sge;
int ret = -ENOMEM;
- gfp_t slab_mask = GFP_NOWAIT;
- gfp_t page_mask = GFP_NOWAIT;
+ gfp_t slab_mask = gfp;
+ gfp_t page_mask = gfp;
if (gfp & __GFP_DIRECT_RECLAIM) {
slab_mask = GFP_KERNEL;
@@ -406,6 +406,16 @@ void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp)
recv = &ic->i_recvs[pos];
ret = rds_ib_recv_refill_one(conn, recv, gfp);
if (ret) {
+ static unsigned long warn_time;
Comment should start on next line.
+ /* warn max once per day. This should be enough to
+ * warn users about low mem situation.
+ */
+ if (printk_timed_ratelimit(&warn_time,
+ 24 * 60 * 60 * 1000))
+ pr_warn("RDS/IB: failed to refill recv buffer for <%pI6c,%pI6c,%d>, waking worker\n",
+ &conn->c_laddr, &conn->c_faddr,
+ conn->c_tos);
Didn't notice this before.
Why not just use "pr_warn_ratelimited()" ?
+
must_wake = true;
break;
}
@@ -1020,7 +1030,7 @@ void rds_ib_recv_cqe_handler(struct rds_ib_connection *ic,
rds_ib_stats_inc(s_ib_rx_ring_empty);
if (rds_ib_ring_low(&ic->i_recv_ring)) {
- rds_ib_recv_refill(conn, 0, GFP_NOWAIT);
+ rds_ib_recv_refill(conn, 0, GFP_NOWAIT | __GFP_NOWARN);
rds_ib_stats_inc(s_ib_rx_refill_from_cq);
}
}
