Re: [dpdk-dev] [PATCH] lib/eal: resolve address conflicts

[David Marchand <david.marchand@redhat.com>]

On Mon, Nov 4, 2019 at 11:15 AM Burakov, Anatoly
<anatoly.burakov@intel.com> wrote:
>
> On 04-Nov-19 6:32 AM, Wangyu (Turing Solution Development Dep) wrote:
> >
> > Resolve address conflicts on 64K pagesize without base_virtaddr, which cause new address conflicts in eal_get_virtual_area().
> >
> > Signed-off-by: Beard-627 <dengxiaofeng@huawei.com>
> > Acked-by: Eric wang <seven.wangyu@huawei.com>
> > Acked-by: Wei Hu <xavier.huwei@huawei.com>
> > Acked-by: Min Hu <humin29@huawei.com>
> > ---
> >   lib/librte_eal/linux/eal/eal.c | 22 ++++++++++++++++++++++
> >   1 file changed, 22 insertions(+)
> >
> > diff --git a/lib/librte_eal/linux/eal/eal.c b/lib/librte_eal/linux/eal/eal.c index 946222c..c15d406 100644
> > --- a/lib/librte_eal/linux/eal/eal.c
> > +++ b/lib/librte_eal/linux/eal/eal.c
> > @@ -360,6 +360,28 @@ enum rte_iova_mode
> >               return -1;
> >       }
> >
> > +     if ((getpagesize() == RTE_PGSIZE_64K) &&
> > +             (internal_config.base_virtaddr == 0)) {
> > +
> > +             munmap(rte_mem_cfg_addr, sizeof(*rte_config.mem_config));
> > +             rte_mem_cfg_addr = (void *)RTE_PTR_ALIGN_CEIL(
> > +                     (uintptr_t)rte_mem_cfg_addr, (size_t)RTE_PGSIZE_16M);
> > +             rte_mem_cfg_addr = (void *)RTE_ALIGN_FLOOR(
> > +                     (uintptr_t)rte_mem_cfg_addr -
> > +                     sizeof(*rte_config.mem_config), sysconf(_SC_PAGE_SIZE));
>
> Please use RTE_PTR_ADD and RTE_PTR_DIFF to perform pointer arithmetic.
>
> > +
> > +             rte_mem_cfg_addr = mmap(rte_mem_cfg_addr,
> > +                     sizeof(*rte_config.mem_config),
> > +                     PROT_READ | PROT_WRITE, MAP_SHARED, mem_cfg_fd, 0);
> > +
> > +             if (rte_mem_cfg_addr == MAP_FAILED) {
> > +                     close(mem_cfg_fd);
> > +                     mem_cfg_fd = -1;
> > +                     RTE_LOG(ERR, EAL, "Cannot mmap memory for rte_config\n");
> > +                     return -1;
> > +             }
> > +     }
> > +
> >       memcpy(rte_mem_cfg_addr, &early_mem_config, sizeof(early_mem_config));
> >       rte_config.mem_config = rte_mem_cfg_addr;
> >
> > --
> > 1.8.3.1
> >
>
> The patch requires a bit more explanation - what exactly is the problem,
> and why the solution is as above? Also, did you test it on the latest
> master, since the eal_get_virtal_area() patches [1] got merged?
>
> [1] http://patches.dpdk.org/project/dpdk/list/?series=7043&state=*

Please, do you still have an issue after the fix Anatoly pointed at?
Thanks.


-- 
David Marchand