On 04/04/2017 11:41 AM, Michal Hocko wrote: > On Thu 30-03-17 17:48:39, Andrey Ryabinin wrote: >> From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> >> Subject: mm/vmalloc: allow to call vfree() in atomic context fix >> >> Don't spawn worker if we already purging. >> >> Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> > I would rather put this into a separate patch. Ideally with some numners > as this is an optimization... Actually, this just mimics what the code was doing before, as it only invoked __purge_vmap_area_lazy() if the trylock succeeded. /Thomas > >> --- >> mm/vmalloc.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/mm/vmalloc.c b/mm/vmalloc.c >> index ea1b4ab..88168b8 100644 >> --- a/mm/vmalloc.c >> +++ b/mm/vmalloc.c >> @@ -737,7 +737,8 @@ static void free_vmap_area_noflush(struct vmap_area *va) >> /* After this point, we may free va at any time */ >> llist_add(&va->purge_list, &vmap_purge_list); >> >> - if (unlikely(nr_lazy > lazy_max_pages())) >> + if (unlikely(nr_lazy > lazy_max_pages()) && >> + !mutex_is_locked(&vmap_purge_lock)) >> schedule_work(&purge_vmap_work); >> } >> >> -- >> 2.10.2 >>