On Tue, 24 Jul 2007, Andrew Morton wrote: > > __GFP_MOVABLE The movability of a slab is determined by the > > options specified at kmem_cache_create time. If this is > > specified at kmalloc time then we will have some random > > slabs movable and others not. > > Yes, they seem inappropriate. Especially the first two.
The third one would randomize __GFP_MOVABLE allocs from the page allocator since one __GFP_MOVABLE alloc may allocate a slab that is then used for !__GFP_MOVABLE allocs. Maybe something like this? Note that we may get into some churn here since slab allocations that any of these flags will BUG. GFP_LEVEL_MASK: Remove __GFP_COLD, __GFP_COMP and __GFPMOVABLE Add an explanation for the GFP_LEVEL_MASK and remove the flags that should not be passed through derived allocators. Signed-off-by: Christoph Lameter <[EMAIL PROTECTED]> Index: linux-2.6/include/linux/gfp.h =================================================================== --- linux-2.6.orig/include/linux/gfp.h 2007-07-24 12:31:04.000000000 -0700 +++ linux-2.6/include/linux/gfp.h 2007-07-24 12:32:50.000000000 -0700 @@ -53,12 +53,15 @@ struct vm_area_struct; #define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */ #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) -/* if you forget to add the bitmask here kernel will crash, period */ +/* + * GFP_LEVEL_MASK is used to filter out flags to be passed on to the + * page allocator in derived allocators such as slab allocators and + * vmalloc. It should not contain flags that are to be handled by the + * derived allocators themselves. + */ #define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \ - __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \ - __GFP_NOFAIL|__GFP_NORETRY|__GFP_COMP| \ - __GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_THISNODE| \ - __GFP_MOVABLE) + __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|__GFP_NORETRY| \ + __GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_THISNODE| __GFP_MOVABLE) /* This equals 0, but use constants in case they ever change */ #define GFP_NOWAIT (GFP_ATOMIC & ~__GFP_HIGH) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
