[PATCH] rds: Fix inaccurate accounting of unsignaled wrs

From: HÃkon Bugge
Date: Tue Oct 24 2017 - 10:16:56 EST


The number of unsignaled work-requests posted to the IB send queue is
tracked by a counter in the rds_ib_connection struct. When it reaches
zero, or the caller explicitly asks for it, the send-signaled bit is
set in send_flags and the counter is reset. This is performed by the
rds_ib_set_wr_signal_state() function.

However, this function is not always used which yields inaccurate
accounting. This commit fixes this, re-factors a code bloat related to
the matter, and makes the actual parameter type to the function
consistent.

Signed-off-by: HÃkon Bugge <haakon.bugge@xxxxxxxxxx>
---
net/rds/ib_send.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/net/rds/ib_send.c b/net/rds/ib_send.c
index 6ab39db..d07ecb0 100644
--- a/net/rds/ib_send.c
+++ b/net/rds/ib_send.c
@@ -661,13 +661,15 @@ int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
}
}

- rds_ib_set_wr_signal_state(ic, send, 0);
+ rds_ib_set_wr_signal_state(ic, send, false);

/*
* Always signal the last one if we're stopping due to flow control.
*/
- if (ic->i_flowctl && flow_controlled && i == (work_alloc-1))
- send->s_wr.send_flags |= IB_SEND_SIGNALED | IB_SEND_SOLICITED;
+ if (ic->i_flowctl && flow_controlled && i == (work_alloc - 1)) {
+ rds_ib_set_wr_signal_state(ic, send, true);
+ send->s_wr.send_flags |= IB_SEND_SOLICITED;
+ }

if (send->s_wr.send_flags & IB_SEND_SIGNALED)
nr_sig++;
@@ -705,11 +707,8 @@ int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
if (scat == &rm->data.op_sg[rm->data.op_count]) {
prev->s_op = ic->i_data_op;
prev->s_wr.send_flags |= IB_SEND_SOLICITED;
- if (!(prev->s_wr.send_flags & IB_SEND_SIGNALED)) {
- ic->i_unsignaled_wrs = rds_ib_sysctl_max_unsig_wrs;
- prev->s_wr.send_flags |= IB_SEND_SIGNALED;
- nr_sig++;
- }
+ if (!(prev->s_wr.send_flags & IB_SEND_SIGNALED))
+ nr_sig += rds_ib_set_wr_signal_state(ic, prev, true);
ic->i_data_op = NULL;
}

--
1.8.3.1