Re: [dpdk-dev] [PATCH v2] librte_lpm: Improve performance of the delete and add functions

[Bruce Richardson <bruce.richardson@intel.com>]

On Fri, Jul 06, 2018 at 07:59:22PM +0300, Alex Kiselev wrote:
> Please see inline replies
> 
> > On Mon, Jul 02, 2018 at 07:42:11PM +0300, Alex Kiselev wrote:
> >> There are two major problems with the library:
> >> first, there is no need to rebuild the whole LPM tree
> >> when a rule is deleted and second, due to the current
> >> rules algorithm with complexity O(n) it's almost
> >> impossible to deal with large rule sets (50k or so rules).
> >> This patch addresses those two issues.
> 
> >> Signed-off-by: Alex Kiselev <alex@therouter.net>
> 
> > Hi,
> 
> > Some initial review comments inline below
> 
> > /Bruce
> >> ---
> >>  lib/librte_lpm/rte_lpm6.c | 1073 ++++++++++++++++++++++++++++++++++-----------
> >>  1 file changed, 816 insertions(+), 257 deletions(-)
> 
<snip>
> >> +/*
> >> + * LPM6 rule hash function
> >> + */
> >> +static inline uint32_t
> >> +rule_hash_crc(const void *data, __rte_unused uint32_t data_len,
> >> +               uint32_t init_val)
> >> +{
> >> +     return rte_hash_crc(data, sizeof(struct rte_lpm6_rule_key), init_val);
> >> +}
> 
> > Why bother passing in the length and making the data a void pointer.
>  
> I beleive it should be compatible with the rte_hash_function prototype.

Ah, ok, you are passing this to rte_hash. Makes sense now. I suggest
putting in a comment explaining why you have the extra unused parameter so.