From 2e7b3b994529d4760231a45a6b88950187bda877 Mon Sep 17 00:00:00 2001 From: Andy Grover Date: Thu, 11 Mar 2010 13:49:59 +0000 Subject: [PATCH] RDS: Fix congestion issues for loopback We have two kinds of loopback: software (via loop transport) and hardware (via IB). sw is used for 127.0.0.1, and doesn't support rdma ops. hw is used for sends to local device IPs, and supports rdma. Both are used in different cases. For both of these, when there is a congestion map update, we want to call rds_cong_map_updated() but not actually send anything -- since loopback local and foreign congestion maps point to the same spot, they're already in sync. The old code never called sw loop's xmit_cong_map(),so rds_cong_map_updated() wasn't being called for it. sw loop ports would not work right with the congestion monitor. Fixing that meant that hw loopback now would send congestion maps to itself. This is also undesirable (racy), so we check for this case in the ib-specific xmit code. Signed-off-by: Andy Grover Signed-off-by: David S. Miller --- net/rds/cong.c | 2 -- net/rds/ib_send.c | 7 +++++++ net/rds/loop.c | 7 ------- 3 files changed, 7 insertions(+), 9 deletions(-) diff --git a/net/rds/cong.c b/net/rds/cong.c index 6d06cac2649c..dd2711df640b 100644 --- a/net/rds/cong.c +++ b/net/rds/cong.c @@ -218,8 +218,6 @@ void rds_cong_queue_updates(struct rds_cong_map *map) spin_lock_irqsave(&rds_cong_lock, flags); list_for_each_entry(conn, &map->m_conn_list, c_map_item) { - if (conn->c_loopback) - continue; if (!test_and_set_bit(0, &conn->c_map_queued)) { rds_stats_inc(s_cong_update_queued); queue_delayed_work(rds_wq, &conn->c_send_w, 0); diff --git a/net/rds/ib_send.c b/net/rds/ib_send.c index f380c3f01256..c18228aec779 100644 --- a/net/rds/ib_send.c +++ b/net/rds/ib_send.c @@ -482,6 +482,13 @@ int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm, BUG_ON(off % RDS_FRAG_SIZE); BUG_ON(hdr_off != 0 && hdr_off != sizeof(struct rds_header)); + /* Do not send cong updates to IB loopback */ + if (conn->c_loopback + && rm->m_inc.i_hdr.h_flags & RDS_FLAG_CONG_BITMAP) { + rds_cong_map_updated(conn->c_fcong, ~(u64) 0); + return sizeof(struct rds_header) + RDS_CONG_MAP_BYTES; + } + /* FIXME we may overallocate here */ if (be32_to_cpu(rm->m_inc.i_hdr.h_len) == 0) i = 1; diff --git a/net/rds/loop.c b/net/rds/loop.c index 4a61997f554d..93a45f1ce61f 100644 --- a/net/rds/loop.c +++ b/net/rds/loop.c @@ -80,16 +80,9 @@ static int rds_loop_xmit_cong_map(struct rds_connection *conn, struct rds_cong_map *map, unsigned long offset) { - unsigned long i; - BUG_ON(offset); BUG_ON(map != conn->c_lcong); - for (i = 0; i < RDS_CONG_MAP_PAGES; i++) { - memcpy((void *)conn->c_fcong->m_page_addrs[i], - (void *)map->m_page_addrs[i], PAGE_SIZE); - } - rds_cong_map_updated(conn->c_fcong, ~(u64) 0); return sizeof(struct rds_header) + RDS_CONG_MAP_BYTES; -- GitLab