On Fri, Oct 11, 2019 at 11:36 AM David Marchand
<david.march...@redhat.com> wrote:
>
> Some comments.
ping.
>
> The title does not reflect the observed issue.
> I understand that secondary processeses can't be started from a docker
> container.
> The patch title should reflect this.
>
> On Wed, Jul 24, 2019 at 10:20 AM <yasufu...@gmail.com> wrote:
> >
> > From: Yasufumi Ogawa <ogawa.yasuf...@lab.ntt.co.jp>
> >
> > In secondary_msl_create_walk(), it creates a file for fbarrays with its
> > PID for reserving unique name among secondary processes. However, it
> > does not work if secondary is run as app container because each of
> > containerized secondary has PID 1. To reserve unique name, use hostname
> > instead of PID because hostname is assigned as a short form of 64
> > digits full container ID in docker.
> >
> > Cc: sta...@dpdk.org
>
> I don't think we want to backport this behavior change.
>
> >
> > Signed-off-by: Yasufumi Ogawa <ogawa.yasuf...@lab.ntt.co.jp>
> > ---
> > lib/librte_eal/linux/eal/eal_memalloc.c | 28 +++++++++++++++++++++++--
> > 1 file changed, 26 insertions(+), 2 deletions(-)
> >
> > diff --git a/lib/librte_eal/linux/eal/eal_memalloc.c
> > b/lib/librte_eal/linux/eal/eal_memalloc.c
> > index 1f6a7c18f..356b304a8 100644
> > --- a/lib/librte_eal/linux/eal/eal_memalloc.c
> > +++ b/lib/librte_eal/linux/eal/eal_memalloc.c
> > @@ -1366,6 +1366,7 @@ secondary_msl_create_walk(const struct
> > rte_memseg_list *msl,
> > struct rte_memseg_list *primary_msl, *local_msl;
> > char name[PATH_MAX];
> > int msl_idx, ret;
> > + char proc_id[33] = { 0 }; /* 32bytes is enough if using hostname */
>
> This variable only makes sense in the if (getpid() == 1) branch,
> please move it there, and see below comment about using gethostname().
>
> >
> > if (msl->external)
> > return 0;
> > @@ -1375,8 +1376,31 @@ secondary_msl_create_walk(const struct
> > rte_memseg_list *msl,
> > local_msl = &local_memsegs[msl_idx];
> >
> > /* create distinct fbarrays for each secondary */
> > - snprintf(name, RTE_FBARRAY_NAME_LEN, "%s_%i",
> > - primary_msl->memseg_arr.name, getpid());
> > + /* If run secondary in a container, the name of fbarray file should
> > + * not be decided with pid because getpid() always returns 1.
> > + * In docker, hostname is assigned as a short form of full container
> > + * ID. So use hostname as unique ID among containers instead.
>
> I understand this is how it works for docker.
> Is this the same in other container environments?
>
>
> > + */
> > + if (getpid() == 1) {
> > + FILE *hn_fp;
> > + hn_fp = fopen("/etc/hostname", "r");
>
> Why not use gethostname() ?
> Plus, this api defines the maximum size of the hostname as HOST_NAME_MAX
> bytes.
>
> > + if (hn_fp == NULL) {
> > + RTE_LOG(ERR, EAL,
> > + "Cannot open '/etc/hostname' for
> > secondary\n");
> > + return -1;
> > + }
> > +
> > + /* with docker, /etc/hostname just has one entry of
> > hostname */
> > + if (fscanf(hn_fp, "%32s", proc_id) == EOF) {
> > + fclose(hn_fp);
> > + return -1;
> > + }
> > + fclose(hn_fp);
> > + } else
> > + sprintf(proc_id, "%d", (int)getpid());
> > +
> > + snprintf(name, RTE_FBARRAY_NAME_LEN, "%s_%s",
> > + primary_msl->memseg_arr.name, proc_id);
> >
> > ret = rte_fbarray_init(&local_msl->memseg_arr, name,
> > primary_msl->memseg_arr.len,
--
David Marchand
