> -----Original Message----- > From: Jianbo Liu [mailto:jianbo....@arm.com] > Sent: Monday, October 30, 2017 3:33 AM > To: Dumitrescu, Cristian <cristian.dumitre...@intel.com> > Cc: dev@dpdk.org > Subject: Re: [PATCH] examples/ip_pipeline: avoid the failure of creating hash > table > > The 10/27/2017 10:01, Dumitrescu, Cristian wrote: > > > > > > > -----Original Message----- > > > From: Jianbo Liu [mailto:jianbo....@arm.com] > > > Sent: Friday, October 27, 2017 3:55 AM > > > To: dev@dpdk.org; Dumitrescu, Cristian <cristian.dumitre...@intel.com> > > > Cc: Jianbo Liu <jianbo....@arm.com> > > > Subject: [PATCH] examples/ip_pipeline: avoid the failure of creating hash > > > table > > > > > > Hash table function will check if the input bucket size is power of 2, > > > so the parameter should be rounded up before sending to the creating > > > function. > > > > > > Signed-off-by: Jianbo Liu <jianbo....@arm.com> > > > --- > > > examples/ip_pipeline/pipeline/pipeline_flow_classification_be.c | 2 +- > > > examples/ip_pipeline/pipeline/pipeline_routing_be.c | 3 ++- > > > 2 files changed, 3 insertions(+), 2 deletions(-) > > > > > > > Existing code is simply letting the library detect the misconfiguration and > gracefully fail. It avoids duplicating library checks in the app. > > > > Your proposal tries to prevent library from failing by silently tweaking > > some > user configuration params. Easier to debug in some cases. > > Yes. but is it must for the parameters to be power of 2? I saw the > config exmple in examples/ip_pipeline/config/network_layers.cfg: > > .... > 178 port_local_dest = 4 ; SINK2 (Drop) > 179 n_arp_entries = 1000 > 180 ip_hdr_offset = 270 > > If not, it's the programmer to correct it before sending to the library. > > Thanks! > Jianbo >
In the latest code, the number of keys does not have to be a power of 2, while the number of buckets does. I am considering changing the implementation to quietly upgrade number of buckets to the next power of 2 to eliminate some of these error cases. +: less things for the (unengaged) user to worry about -: number of buckets needs to be a power of two internally, so a non-power of 2 is likely a misconfiguration; the memory footprint can get much higher when quiet upgrade takes place > > > > For this case, I am OK with your proposal, although not really required, so: > > > > Acked-by: Cristian Dumitrescu <cristian.dumitre...@intel.com> > > > IMPORTANT NOTICE: The contents of this email and any attachments are > confidential and may also be privileged. If you are not the intended > recipient, > please notify the sender immediately and do not disclose the contents to any > other person, use it for any purpose, or store or copy the information in any > medium. Thank you.
