From: Paolo Abeni <[email protected]> Date: Fri, 22 Mar 2019 16:01:54 +0100
> This patch series is aimed at improving xmit performances of lockless qdisc > in the uncontended scenario. > > After the lockless refactor pfifo_fast can't leverage the BYPASS optimization. > Due to retpolines the overhead for the avoidables enqueue and dequeue > operations > has increased and we see measurable regressions. > > The first patch introduces the BYPASS code path for lockless qdisc, and the > second one optimizes such path further. Overall this avoids up to 3 indirect > calls per xmit packet. Detailed performance figures are reported in the 2nd > patch. > > v2 -> v3: > - qdisc_is_empty() has a const argument (Eric) > > v1 -> v2: > - use really an 'empty' flag instead of 'not_empty', as > suggested by Eric Looks great, series applied, thanks Paolo.
