| Message ID | 20180528213632.1412353-1-songliubraving@fb.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next] net: remove bypassed check in sch_direct_xmit() | expand |
Hello! On 5/29/2018 12:36 AM, Song Liu wrote: > Check sch_direct_xmit() at the end of sch_direct_xmit() will be bypassed. "Checking netif_xmit_frozen_or_stopped()", perhaps? Else it doesn't make much sense... > This is because "ret" from sch_direct_xmit() will be either NETDEV_TX_OK > or NETDEV_TX_BUSY, and only ret == NETDEV_TX_OK == 0 will reach the > condition: > > if (ret && netif_xmit_frozen_or_stopped(txq)) > return false; > > This patch cleans up the code by removing the whole condition. > > For more discussion about this, please refer to > https://marc.info/?t=152727195700008 > > Signed-off-by: Song Liu <songliubraving@fb.com> > Cc: John Fastabend <john.fastabend@gmail.com> > Cc: Alexei Starovoitov <ast@kernel.org> > Cc: David S. Miller <davem@davemloft.net> [...] MBR, Sergei
> On May 29, 2018, at 1:58 AM, Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> wrote: > > Hello! > > On 5/29/2018 12:36 AM, Song Liu wrote: > >> Check sch_direct_xmit() at the end of sch_direct_xmit() will be bypassed. > > "Checking netif_xmit_frozen_or_stopped()", perhaps? Else it doesn't make much sense... Thanks Sergei! Sending v2 with fix. Song > >> This is because "ret" from sch_direct_xmit() will be either NETDEV_TX_OK >> or NETDEV_TX_BUSY, and only ret == NETDEV_TX_OK == 0 will reach the >> condition: >> if (ret && netif_xmit_frozen_or_stopped(txq)) >> return false; >> This patch cleans up the code by removing the whole condition. >> For more discussion about this, please refer to >> https://marc.info/?t=152727195700008 >> Signed-off-by: Song Liu <songliubraving@fb.com> >> Cc: John Fastabend <john.fastabend@gmail.com> >> Cc: Alexei Starovoitov <ast@kernel.org> >> Cc: David S. Miller <davem@davemloft.net> > [...] > > MBR, Sergei
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 760ab1b..69078c8 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -346,9 +346,6 @@ bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, return false; } - if (ret && netif_xmit_frozen_or_stopped(txq)) - return false; - return true; }
Check sch_direct_xmit() at the end of sch_direct_xmit() will be bypassed. This is because "ret" from sch_direct_xmit() will be either NETDEV_TX_OK or NETDEV_TX_BUSY, and only ret == NETDEV_TX_OK == 0 will reach the condition: if (ret && netif_xmit_frozen_or_stopped(txq)) return false; This patch cleans up the code by removing the whole condition. For more discussion about this, please refer to https://marc.info/?t=152727195700008 Signed-off-by: Song Liu <songliubraving@fb.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: David S. Miller <davem@davemloft.net> --- net/sched/sch_generic.c | 3 --- 1 file changed, 3 deletions(-)