On 2017/01/13 0:37, Michal Hocko wrote:
> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
> index 5dc34653274a..105cd04c7414 100644
> --- a/drivers/vhost/net.c
> +++ b/drivers/vhost/net.c
> @@ -797,12 +797,9 @@ static int vhost_net_open(struct inode *inode, struct
> file *f)
> struct vhost_virtqueue **vqs;
> int i;
>
> - n = kmalloc(sizeof *n, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
> - if (!n) {
> - n = vmalloc(sizeof *n);
> - if (!n)
> - return -ENOMEM;
> - }
> + n = kvmalloc(sizeof *n, GFP_KERNEL | __GFP_REPEAT);
An opportunity to standardize as sizeof(*n) like other allocations.
> diff --git a/mm/util.c b/mm/util.c
> index 7e0c240b5760..9306244b9f41 100644
> --- a/mm/util.c
> +++ b/mm/util.c
> @@ -333,7 +333,8 @@ EXPORT_SYMBOL(vm_mmap);
> * Uses kmalloc to get the memory but if the allocation fails then falls back
> * to the vmalloc allocator. Use kvfree for freeing the memory.
> *
> - * Reclaim modifiers - __GFP_NORETRY, __GFP_REPEAT and __GFP_NOFAIL are not
> supported
> + * Reclaim modifiers - __GFP_NORETRY and __GFP_NOFAIL are not supported.
> __GFP_REPEAT
> + * is supported only for large (>64kB) allocations
Isn't this ">32kB" (i.e. __GFP_REPEAT is supported for 64kB allocation) ?
> */
> void *kvmalloc_node(size_t size, gfp_t flags, int node)
> {
> @@ -350,8 +351,18 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
> * Make sure that larger requests are not too disruptive - no OOM
> * killer and no allocation failure warnings as we have a fallback
> */
> - if (size > PAGE_SIZE)
> - kmalloc_flags |= __GFP_NORETRY | __GFP_NOWARN;
> + if (size > PAGE_SIZE) {
> + kmalloc_flags |= __GFP_NOWARN;
> +
> + /*
> + * We have to override __GFP_REPEAT by __GFP_NORETRY for !costly
> + * requests because there is no other way to tell the allocator
> + * that we want to fail rather than retry endlessly.
> + */
> + if (!(kmalloc_flags & __GFP_REPEAT) ||
> + (size <= PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER))
> + kmalloc_flags |= __GFP_NORETRY;
> + }
>
> ret = kmalloc_node(size, kmalloc_flags, node);
>
>
