The patch titled
Subject: linux/bitmap.h: relax comment on compile-time constant nbits
has been added to the -mm tree. Its filename is
linux-bitmaph-relax-comment-on-compile-time-constant-nbits.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/linux-bitmaph-relax-comment-on-compile-time-constant-nbits.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/linux-bitmaph-relax-comment-on-compile-time-constant-nbits.patch
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------------------------------------------------------
From: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Subject: linux/bitmap.h: relax comment on compile-time constant nbits
It's not clear what's so horrible about emitting a function call to handle
a run-time sized bitmap. Moreover, gcc also emits a function call for a
compile-time-constant-but-huge nbits, so the comment isn't even accurate.
Link: http://lkml.kernel.org/r/20180818131623.8755-6-linux@xxxxxxxxxxxxxxxxxx
Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx>
Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/bitmap.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/include/linux/bitmap.h~linux-bitmaph-relax-comment-on-compile-time-constant-nbits
+++ a/include/linux/bitmap.h
@@ -28,8 +28,8 @@
* The available bitmap operations and their rough meaning in the
* case that the bitmap is a single unsigned long are thus:
*
- * Note that nbits should be always a compile time evaluable constant.
- * Otherwise many inlines will generate horrible code.
+ * The generated code is more efficient when nbits is known at
+ * compile-time and at most BITS_PER_LONG.
*
* ::
*
_
Patches currently in -mm which might be from linux@xxxxxxxxxxxxxxxxxx are
lib-bitmapc-remove-wrong-documentation.patch
linux-bitmaph-handle-constant-zero-size-bitmaps-correctly.patch
linux-bitmaph-remove-redundant-uses-of-small_const_nbits.patch
linux-bitmaph-fix-type-of-nbits-in-bitmap_shift_right.patch
linux-bitmaph-relax-comment-on-compile-time-constant-nbits.patch
lib-bitmapc-fix-remaining-space-computation-in-bitmap_print_to_pagebuf.patch
lib-bitmapc-simplify-bitmap_print_to_pagebuf.patch
