Re: [RFC] bitmap relative operator for mempolicy extensions

[David Rientjes <rientjes@google.com>]

On Thu, 14 Feb 2008, Ray Lee wrote:

> map_bitmap violates your naming convention, bitmap_map isn't all that
> clear, bitmap_remap is taken, and while it is one-to-one and onto, I
> think calling it bitmap_bijection would lose everyone except the
> mathematicians. bitmap_onto? bitmap_map_onto? bitmap_map_bitmap_onto?
> 

Whatever this operation ends up being called should be mirrored in the 
name of the new mempolicy flag being introduced, so this will need to be 
finalized before MPOL_F_RELATIVE_NODES can be proposed.

> Minor suggestion:
> + * and the n-th bit of @relmap is the m-th set bit of @relmap.
> 
> Perhaps s/is the/is also the/, so that the reader doesn't try to
> second guess if you accidentally wrote @relmap twice instead of one of
> them being @orig.
> 

There's also an extra "is" in the description:

--- 2.6.24-mm1.orig/lib/bitmap.c	2008-02-04 10:41:35.656945848 -0800
+++ 2.6.24-mm1/lib/bitmap.c	2008-02-14 03:18:08.190311785 -0800
@@ -698,6 +698,69 @@ int bitmap_bitremap(int oldbit, const un
 }
 EXPORT_SYMBOL(bitmap_bitremap);
 
+/**
+ * bitmap_relative - translate one bitmap relative to another
+ *	@dst: resulting translated bitmap
+ * 	@orig: original untranslated bitmap
+ * 	@relmap: bitmap relative to which translated
+ *	@bits: number of bits in each of these bitmaps
+ *
+ * Set the n-th bit of @dst iff there exists some m such that the
+ * n-th bit of @relmap is set, the m-th bit of @orig is is set,

on the last line of this snippet.

		David