linux-kernel - [PATCH] bitops: Add a comment explaining the double underscore macros

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <0ffbc9c3-7a7c-4cbe-bdb7-1041df44ce53@kili.mountain>
Date: Mon, 10 Jun 2024 12:18:03 +0300
From: Dan Carpenter <dan.carpenter@...aro.org>
To: Yury Norov <yury.norov@...il.com>
Cc: Rasmus Villemoes <linux@...musvillemoes.dk>,
	linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org,
	Linus Walleij <linus.walleij@...aro.org>
Subject: [PATCH] bitops: Add a comment explaining the double underscore macros

Linus Walleij pointed out that a new comer might be confused about the
difference between set_bit() and __set_bit().  Add a comment explaining
the difference.

Link: https://lore.kernel.org/all/CACRpkdZFPG_YLici-BmYfk9HZ36f4WavCN3JNotkk8cPgCODCg@mail.gmail.com/
Signed-off-by: Dan Carpenter <dan.carpenter@...aro.org>
---
 include/linux/bitops.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 46d4bdc634c0..b35a5c3783f6 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -29,6 +29,9 @@ extern unsigned long __sw_hweight64(__u64 w);
 #include <asm-generic/bitops/generic-non-atomic.h>
 
 /*
+ * These double underscore __set_bit(), __clear_bit() macros are non-atomic
+ * versions of set_bit(), clear_bit() and so on.
+ *
  * Many architecture-specific non-atomic bitops contain inline asm code and due
  * to that the compiler can't optimize them to compile-time expressions or
  * constants. In contrary, generic_*() helpers are defined in pure C and
-- 
2.39.2