Messages in this thread | | | Date | Thu, 22 Dec 2022 00:50:22 -0800 | From | Christoph Hellwig <> | Subject | Re: [PATCH v2 2/3] mm: vmalloc: Switch to find_unlink_vmap_area() in vm_unmap_ram() |
| |
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
On Wed, Dec 21, 2022 at 06:44:53PM +0100, Uladzislau Rezki (Sony) wrote: > Switch from find_vmap_area() to find_unlink_vmap_area() to prevent > a double access to the vmap_area_lock: one for finding area, second > time is for unlinking from a tree. > > Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> > --- > mm/vmalloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 28030d2441f1..17e688cc7357 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -2251,7 +2251,7 @@ void vm_unmap_ram(const void *mem, unsigned int count) > return; > } > > - va = find_vmap_area(addr); > + va = find_unlink_vmap_area(addr);
I can't find find_unlink_vmap_area in current -next, but shouldn't this also switch from free_vmap_area_noflush to something that doesn't unlink from the list and avoid the lock?
In general the code could probably use a bit of refactoring to split unmapping from freeing.
| |