| Message ID | 20221011071128.3470622-4-houtao@huaweicloud.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Remove unnecessary RCU grace period chaining | expand |
On Tue, Oct 11, 2022 at 03:11:28PM +0800, Hou Tao wrote: > From: Hou Tao <houtao1@huawei.com> > > To support sleepable uprobe bpf program, the freeing of trace program > array chains a RCU-tasks-trace grace period with a normal RCU grace > period. But considering in the current implementation of RCU-tasks-trace > that one RCU-tasks-trace grace period implies one normal RCU grace > period, so it is not need for such chaining and it is safe to free the > array in the callback of call_rcu_tasks_trace(). And the same here. ;-) Thanx, Paul > Signed-off-by: Hou Tao <houtao1@huawei.com> > --- > kernel/bpf/core.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c > index 711fd293b6de..f943620b55b0 100644 > --- a/kernel/bpf/core.c > +++ b/kernel/bpf/core.c > @@ -2247,12 +2247,15 @@ void bpf_prog_array_free(struct bpf_prog_array *progs) > kfree_rcu(progs, rcu); > } > > +/* Now RCU Tasks grace period implies RCU grace period, so no need to call > + * kfree_rcu(), just call kfree() directly. > + */ > static void __bpf_prog_array_free_sleepable_cb(struct rcu_head *rcu) > { > struct bpf_prog_array *progs; > > progs = container_of(rcu, struct bpf_prog_array, rcu); > - kfree_rcu(progs, rcu); > + kfree(progs); > } > > void bpf_prog_array_free_sleepable(struct bpf_prog_array *progs) > -- > 2.29.2 >
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 711fd293b6de..f943620b55b0 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -2247,12 +2247,15 @@ void bpf_prog_array_free(struct bpf_prog_array *progs) kfree_rcu(progs, rcu); } +/* Now RCU Tasks grace period implies RCU grace period, so no need to call + * kfree_rcu(), just call kfree() directly. + */ static void __bpf_prog_array_free_sleepable_cb(struct rcu_head *rcu) { struct bpf_prog_array *progs; progs = container_of(rcu, struct bpf_prog_array, rcu); - kfree_rcu(progs, rcu); + kfree(progs); } void bpf_prog_array_free_sleepable(struct bpf_prog_array *progs)