On Tue, Jun 23, 2020 at 05:00:53PM +0200, Toke Høiland-Jørgensen wrote:

This reverts commit 191cf872190de28a92e1bd2b56d8860e37e07443.

That commit should never have been backported since it relies on a change in locking semantics that was introduced in v4.8 and not backported. Because of this, the backported commit to sch_fq leads to lockups because of the double locking.

Signed-off-by: Toke Høiland-Jørgensen toke@redhat.com

net/sched/sch_fq.c | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c index f4aa2ab4713a..eb814ffc0902 100644 --- a/net/sched/sch_fq.c +++ b/net/sched/sch_fq.c @@ -830,24 +830,20 @@ nla_put_failure: static int fq_dump_stats(struct Qdisc *sch, struct gnet_dump *d) { struct fq_sched_data *q = qdisc_priv(sch);

• struct tc_fq_qd_stats st;
• sch_tree_lock(sch);
• st.gc_flows = q->stat_gc_flows;
• st.highprio_packets = q->stat_internal_packets;
• st.tcp_retrans = q->stat_tcp_retrans;
• st.throttled = q->stat_throttled;
• st.flows_plimit = q->stat_flows_plimit;
• st.pkts_too_long = q->stat_pkts_too_long;
• st.allocation_errors = q->stat_allocation_errors;
• st.time_next_delayed_flow = q->time_next_delayed_flow - ktime_get_ns();
• st.flows = q->flows;
• st.inactive_flows = q->inactive_flows;
• st.throttled_flows = q->throttled_flows;
• st.pad = 0;
• sch_tree_unlock(sch);

• u64 now = ktime_get_ns();
• struct tc_fq_qd_stats st = {

• .gc_flows		= q->stat_gc_flows,
  

• .highprio_packets	= q->stat_internal_packets,
  

• .tcp_retrans		= q->stat_tcp_retrans,
  

• .throttled		= q->stat_throttled,
  

• .flows_plimit		= q->stat_flows_plimit,
  

• .pkts_too_long		= q->stat_pkts_too_long,
  

• .allocation_errors	= q->stat_allocation_errors,
  

• .flows			= q->flows,
  

• .inactive_flows		= q->inactive_flows,
  

• .throttled_flows	= q->throttled_flows,
  

• .time_next_delayed_flow	= q->time_next_delayed_flow - now,
  

• };

return gnet_stats_copy_app(d, &st, sizeof(st)); } -- 2.27.0

Thanks, now applied.

greg k-h