mirror of https://gitee.com/openkylin/linux.git
0287587884
Testing xmit_more support with netperf and connected UDP sockets, I found strange dst refcount false sharing. Current handling of IFF_XMIT_DST_RELEASE is not optimal. Dropping dst in validate_xmit_skb() is certainly too late in case packet was queued by cpu X but dequeued by cpu Y The logical point to take care of drop/force is in __dev_queue_xmit() before even taking qdisc lock. As Julian Anastasov pointed out, need for skb_dst() might come from some packet schedulers or classifiers. This patch adds new helper to cleanly express needs of various drivers or qdiscs/classifiers. Drivers that need skb_dst() in their ndo_start_xmit() should call following helper in their setup instead of the prior : dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; -> netif_keep_dst(dev); Instead of using a single bit, we use two bits, one being eventually rebuilt in bonding/team drivers. The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being rebuilt in bonding/team. Eventually, we could add something smarter later. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net> |
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lmc | ||
.gitignore | ||
Kconfig | ||
Makefile | ||
c101.c | ||
cosa.c | ||
cosa.h | ||
dlci.c | ||
dscc4.c | ||
farsync.c | ||
farsync.h | ||
hd64570.c | ||
hd64570.h | ||
hd64572.c | ||
hd64572.h | ||
hdlc.c | ||
hdlc_cisco.c | ||
hdlc_fr.c | ||
hdlc_ppp.c | ||
hdlc_raw.c | ||
hdlc_raw_eth.c | ||
hdlc_x25.c | ||
hostess_sv11.c | ||
ixp4xx_hss.c | ||
lapbether.c | ||
n2.c | ||
pc300too.c | ||
pci200syn.c | ||
sbni.c | ||
sbni.h | ||
sdla.c | ||
sealevel.c | ||
wanxl.c | ||
wanxl.h | ||
wanxlfw.S | ||
wanxlfw.inc_shipped | ||
x25_asy.c | ||
x25_asy.h | ||
z85230.c | ||
z85230.h |