Re: [RFC PATCH 07/13] net: sched: support qdisc_reset on NOLOCK qdisc
From: Eric Dumazet <hidden>
Date: 2016-08-17 23:08:10
On Wed, 2016-08-17 at 12:36 -0700, John Fastabend wrote:
The qdisc_reset operation depends on the qdisc lock at the moment to halt any additions to gso_skb and statistics while the list is free'd and the stats zeroed.
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quoted hunk ↗ jump to hunk
Signed-off-by: John Fastabend <redacted> --- net/sched/sch_generic.c | 45 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 35 insertions(+), 10 deletions(-)diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 3b9a21f..29238c4 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c@@ -737,6 +737,20 @@ void qdisc_reset(struct Qdisc *qdisc) kfree_skb(qdisc->skb_bad_txq); qdisc->skb_bad_txq = NULL; + if (qdisc->gso_cpu_skb) { + int i; + + for_each_possible_cpu(i) { + struct gso_cell *cell; + + cell = per_cpu_ptr(qdisc->gso_cpu_skb, i); + if (cell) { + kfree_skb_list(cell->skb); + cell = NULL;
You probably wanted : cell->skb = NULL;
quoted hunk ↗ jump to hunk
+ } + } + } + if (qdisc->gso_skb) { kfree_skb_list(qdisc->gso_skb); qdisc->gso_skb = NULL;@@ -812,10 +826,6 @@ struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, root_lock = qdisc_lock(oqdisc); spin_lock_bh(root_lock); - /* Prune old scheduler */ - if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1) - qdisc_reset(oqdisc); -
This probably belongs to a separate patch, before any per cpu / lockless qdisc changes ?