On 10.03.21 16:08, Oscar Salvador wrote:
Currently, __alloc_contig_migrate_range can generate -EINTR, -ENOMEM or -EBUSY, and report them down the chain. The problem is that when migrate_pages() reports -ENOMEM, we keep going till we exhaust all the try-attempts (5 at the moment) instead of bailing out.migrate_pages bails out right away on -ENOMEM because it is considered a fatal error. Do the same here instead of keep going and retrying. Signed-off-by: Oscar Salvador <osalva...@suse.de> --- mm/page_alloc.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3e4b29ee2b1e..94467f1b85ff 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -8484,7 +8484,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, } tries = 0; } else if (++tries == 5) { - ret = ret < 0 ? ret : -EBUSY; + ret = -EBUSY; break; }@@ -8494,6 +8494,12 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, ret = migrate_pages(&cc->migratepages, alloc_migration_target,NULL, (unsigned long)&mtc, cc->mode, MR_CONTIG_RANGE); + /* + * On -ENOMEM, migrate_pages() bails out right away. It is pointless + * to retry again over this error, so do the same here. + */ + if (ret == -ENOMEM) + break;
I would have thought we could also be able to get other fatal errors from migrate_pages(), but doesn't seem like it
Reviewed-by: David Hildenbrand <da...@redhat.com> -- Thanks, David / dhildenb
