diff options
author | Tejun Heo <tj@kernel.org> | 2010-08-01 05:50:12 -0400 |
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committer | Tejun Heo <tj@kernel.org> | 2010-08-01 05:50:12 -0400 |
commit | 098849516dd522a343e659740c8f1394a5b7fa69 (patch) | |
tree | 46e902aabf3734c68173e959735ee75760b9f911 | |
parent | 40f2b6ffe525e975203c1621d4d4abaa7689b674 (diff) |
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@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r-- | kernel/workqueue.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index e5cb7faac58..1105c474073 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, | |||
271 | return __next_gcwq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2); | 271 | return __next_gcwq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2); |
272 | } | 272 | } |
273 | 273 | ||
274 | /* | ||
275 | * CPU iterators | ||
276 | * | ||
277 | * An extra gcwq is defined for an invalid cpu number | ||
278 | * (WORK_CPU_UNBOUND) to host workqueues which are not bound to any | ||
279 | * specific CPU. The following iterators are similar to | ||
280 | * for_each_*_cpu() iterators but also considers the unbound gcwq. | ||
281 | * | ||
282 | * for_each_gcwq_cpu() : possible CPUs + WORK_CPU_UNBOUND | ||
283 | * for_each_online_gcwq_cpu() : online CPUs + WORK_CPU_UNBOUND | ||
284 | * for_each_cwq_cpu() : possible CPUs for bound workqueues, | ||
285 | * WORK_CPU_UNBOUND for unbound workqueues | ||
286 | */ | ||
274 | #define for_each_gcwq_cpu(cpu) \ | 287 | #define for_each_gcwq_cpu(cpu) \ |
275 | for ((cpu) = __next_gcwq_cpu(-1, cpu_possible_mask, 3); \ | 288 | for ((cpu) = __next_gcwq_cpu(-1, cpu_possible_mask, 3); \ |
276 | (cpu) < WORK_CPU_NONE; \ | 289 | (cpu) < WORK_CPU_NONE; \ |