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

From: Liam Howlett
Date: Mon May 31 2021 - 12:56:49 EST


* 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 ?


> }
> 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
>
>