26/01/2018 08:30, Lu, Wenzhuo: > From: Thomas Monjalon [mailto:tho...@monjalon.net] > > 25/01/2018 02:11, Lu, Wenzhuo: > > > > --- a/app/test-pmd/testpmd.c > > > > +++ b/app/test-pmd/testpmd.c > > > > @@ -305,9 +305,7 @@ struct fwd_engine * fwd_engines[] = { > > > > */ > > > > struct rte_eth_rxmode rx_mode = { > > > > .max_rx_pkt_len = ETHER_MAX_LEN, /**< Default maximum frame > > > > length. */ > > > > - .offloads = (DEV_RX_OFFLOAD_VLAN_FILTER | > > > > - DEV_RX_OFFLOAD_VLAN_STRIP | > > > > - DEV_RX_OFFLOAD_CRC_STRIP), > > > > + .offloads = 0, > > > > > > Change the default behavior may trigger other problems. I think TX offload > > could be a good reference. Get the capability and check what's supported > > first, then ignore the not supported functions with printing a warning but > > not block anything... > > > > I agree that we should check the capabilities before requesting an offload. > > But I disagree on another point: we should not enable an offload if the user > > did not request it explicitly. It makes things unclear. > > This is a testing tool, it should be close to the ethdev API behavior. > > > > Why these offload flags are silently enabled? > > I don't think it's silently. It's a global configuration. In this case, > testpmd is the user, it does request it explicitly. If it's not so explicit, > maybe we can consider moving all the configuration to a specific configure > file. > Talking about why it's enabled by default. Hard to figure out the history. To > my opinion, the original designer wants to simulate the common case.
Please do not justify a design mistake by history. This is a test tool, so we don't care about the common case. A test tool should not try to guess the best configuration. Only the user should decide the configuration to apply, and the default should be empty, as the API is.
