[PATCH v3 5/8] mm/hwpoison: don't set migration type twice to avoid hold heavy contend zone->lock

v1 -> v2: * add more explanation in patch description. v2 -> v3: * set MIGRATE_ISOLATE only if it's not set. Set pageblock migration type will hold zone->lock which is heavy contended in system to avoid race. However, soft offline page will set pageblock migration type twice during get page if

[PATCH v3 5/8] mm/hwpoison: don't set migration type twice to avoid hold heavy contend zone-lock

v1 - v2: * add more explanation in patch description. v2 - v3: * set MIGRATE_ISOLATE only if it's not set. Set pageblock migration type will hold zone-lock which is heavy contended in system to avoid race. However, soft offline page will set pageblock migration type twice during get page if