It is now easy to add busy polling support to a NAPI driver,
with very little impact on normal input path.
This patch serves as a reference implementation.
Note:
A followup patch will add proper napi_complete_done() in mlx5,
so that LINUX_MIB_BUSYPOLLRXPACKETS snmp counter is properly handled.
Tested:
Normal TCP_RR results without busy polling :
lpk51:~# echo 0 >/proc/sys/net/core/busy_read
lpk52:~# echo 0 >/proc/sys/net/core/busy_read
lpk51:~# ./netperf -H 192.168.4.52 -t TCP_RR -l 10
MIGRATED TCP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.4.52 () port 0 AF_INET : first burst 0
Local /Remote
Socket Size Request Resp. Elapsed Trans.
Send Recv Size Size Time Rate
bytes Bytes bytes bytes secs. per sec
16384 87380 1 1 10.00 53509.49
16384 87380
Now enable busy polling :
lpk51:~# echo 70 >/proc/sys/net/core/busy_read
lpk52:~# echo 70 >/proc/sys/net/core/busy_read
lpk51:~# ./netperf -H 192.168.4.52 -t TCP_RR -l 10
MIGRATED TCP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.4.52 () port 0 AF_INET : first burst 0
Local /Remote
Socket Size Request Resp. Elapsed Trans.
Send Recv Size Size Time Rate
bytes Bytes bytes bytes secs. per sec
16384 87380 1 1 10.00 97530.92
16384 87380
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
7ae92ae588