Re: [PATCH V2 2/6] mm/sparse: free section usage memory in case populate_section_memmap failed

From: Dong Aisheng
Date: Mon May 31 2021 - 22:39:10 EST


On Mon, May 31, 2021 at 11:06 PM Liam Howlett <liam.howlett@xxxxxxxxxx> wrote:
>
> * Dong Aisheng <aisheng.dong@xxxxxxx> [210531 05:20]:
> > Free section usage memory in case populate_section_memmap failed.
> > We use map_count to track the remain unused memory to be freed.
> >
> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > Cc: Mike Rapoport <rppt@xxxxxxxxxx>
> > Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>
> > ---
> > ChangeLog:
> > v1->v2:
> > * using goto + lable according to Mike's suggestion
> > ---
> > mm/sparse.c | 11 +++++++----
> > 1 file changed, 7 insertions(+), 4 deletions(-)
> >
> > diff --git a/mm/sparse.c b/mm/sparse.c
> > index 7ac481353b6b..408b737e168e 100644
> > --- a/mm/sparse.c
> > +++ b/mm/sparse.c
> > @@ -533,7 +533,7 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
> > mem_section_usage_size() * map_count);
> > if (!usage) {
> > pr_err("%s: node[%d] usemap allocation failed", __func__, nid);
> > - goto failed;
> > + goto failed1;
>
> Please use better labels for goto statements. Perhaps usemap_failed ?
>

Thanks, I will improve it.

Regards
Aisheng

>
> > }
> > sparse_buffer_init(map_count * section_map_size(), nid);
> > for_each_present_section_nr(pnum_begin, pnum) {
> > @@ -548,17 +548,20 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
> > pr_err("%s: node[%d] memory map backing failed. Some memory will not be available.",
> > __func__, nid);
> > pnum_begin = pnum;
> > - sparse_buffer_fini();
> > - goto failed;
> > + goto failed2;
>
> Again, this goto label is not descriptive.
>
> > }
> > check_usemap_section_nr(nid, usage);
> > sparse_init_one_section(__nr_to_section(pnum), pnum, map, usage,
> > SECTION_IS_EARLY);
> > usage = (void *) usage + mem_section_usage_size();
> > + map_count--;
> > }
> > sparse_buffer_fini();
> > return;
> > -failed:
> > +failed2:
> > + sparse_buffer_fini();
> > + memblock_free_early(__pa(usage), map_count * mem_section_usage_size());
> > +failed1:
> > /* We failed to allocate, mark all the following pnums as not present */
> > for_each_present_section_nr(pnum_begin, pnum) {
> > struct mem_section *ms;
> > --
> > 2.25.1
> >
> >