linux-kernel - [PATCH wq#for-next] workqueue: explain for_each_*cwq

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

Message-ID: <4C55444B.9030804@kernel.org>
Date:	Sun, 01 Aug 2010 11:54:19 +0200
From:	Tejun Heo <tj@...nel.org>
To:	Andrew Morton <akpm@...ux-foundation.org>
CC:	Suresh Siddha <suresh.b.siddha@...el.com>,
	"H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	LKML <linux-kernel@...r.kernel.org>,
	Oleg Nesterov <oleg@...hat.com>
Subject: [PATCH wq#for-next] workqueue: explain for_each_*cwq_cpu() iterators

for_each_*cwq_cpu() are similar to regular CPU iterators except that
it also considers the pseudo CPU number used for unbound workqueues.
Explain them.

Signed-off-by: Tejun Heo <tj@...nel.org>
Cc: Andrew Morton <akpm@...ux-foundation.org>
---
 kernel/workqueue.c |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index e5cb7fa..1105c47 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -271,6 +271,19 @@ static inline int __next_wq_cpu(int cpu, const struct cpumask *mask,
 	return __next_gcwq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2);
 }

+/*
+ * CPU iterators
+ *
+ * An extra gcwq is defined for an invalid cpu number
+ * (WORK_CPU_UNBOUND) to host workqueues which are not bound to any
+ * specific CPU.  The following iterators are similar to
+ * for_each_*_cpu() iterators but also considers the unbound gcwq.
+ *
+ * for_each_gcwq_cpu()		: possible CPUs + WORK_CPU_UNBOUND
+ * for_each_online_gcwq_cpu()	: online CPUs + WORK_CPU_UNBOUND
+ * for_each_cwq_cpu()		: possible CPUs for bound workqueues,
+ *				  WORK_CPU_UNBOUND for unbound workqueues
+ */
 #define for_each_gcwq_cpu(cpu)						\
 	for ((cpu) = __next_gcwq_cpu(-1, cpu_possible_mask, 3);		\
 	     (cpu) < WORK_CPU_NONE;					\
-- 
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/