Re: [PATCH libnftnl] src: add dynamic register allocation infrastructure

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Sat, May 14, 2022 at 06:49:35PM +0200, Phil Sutter wrote:
> Hi Pablo,
> 
> On Mon, May 02, 2022 at 01:07:44PM +0200, Pablo Neira Ayuso wrote:
> > Starting Linux kernel 5.18-rc, operations on registers that already
> > contain the expected data are turned into noop.
> > 
> > Track operation on registers to use the same register through
> > nftnl_reg_get(). This patch introduces an LRU eviction strategy when all
> > the registers are in used.
> > 
> > nftnl_reg_get_scratch() is used to allocate a register as scratchpad
> > area: no tracking is performed in this case, although register eviction
> > might occur.
> > 
> > Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
> > ---
> >  include/expr_ops.h           |   6 +
> >  include/internal.h           |   1 +
> >  include/libnftnl/Makefile.am |   1 +
> >  include/regs.h               |  32 ++++++
> >  src/Makefile.am              |   1 +
> >  src/expr/meta.c              |  44 +++++++
> >  src/expr/payload.c           |  31 +++++
> >  src/libnftnl.map             |   7 ++
> >  src/regs.c                   | 216 +++++++++++++++++++++++++++++++++++
> >  9 files changed, 339 insertions(+)
> >  create mode 100644 include/regs.h
> >  create mode 100644 src/regs.c
> 
> Did you forget to add include/libnftnl/regs.h to this patch? It is
> referenced from src/regs.c and build fails.

Yes, this is fixed here:

http://git.netfilter.org/libnftnl/commit/?id=e549f5b3239c19f78af2f7c7a582fe5616403ca8