On Tue, 25 May 2021, Vlastimil Babka wrote: > Slub has a static spinlock protected bitmap for marking which objects are on > freelist when it wants to list them, for situations where dynamically > allocating such map can lead to recursion or locking issues, and on-stack > bitmap would be too large. > > The handlers of sysfs files alloc_calls and free_calls also currently use this > shared bitmap, but their syscall context makes it straightforward to allocate a > private map before entering locked sections, so switch these processing paths > to use a private bitmap. Right in that case a GFP_KERNEL allocation is fine and you can avoid the static map. Acked-by: Christoph Lameter <cl@xxxxxxxxx>
