Add a new API to iterate free ids. blk-mq-tag will use it.
Signed-off-by: Shaohua Li <[email protected]>
---
include/linux/percpu_ida.h | 3 +++
lib/percpu_ida.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 47 insertions(+)
Index: master/include/linux/percpu_ida.h
===================================================================
--- master.orig/include/linux/percpu_ida.h 2013-10-11 12:14:56.932543376 +0800
+++ master/include/linux/percpu_ida.h 2013-10-11 12:14:56.928543501 +0800
@@ -73,4 +73,7 @@ static inline int percpu_ida_init(struct
IDA_DEFAULT_PCPU_BATCH_MOVE);
}
+int percpu_ida_for_each_free(struct percpu_ida *pool,
+ int (*fn)(int id, void *data), void *data);
+
#endif /* __PERCPU_IDA_H__ */
Index: master/lib/percpu_ida.c
===================================================================
--- master.orig/lib/percpu_ida.c 2013-10-11 12:14:56.932543376 +0800
+++ master/lib/percpu_ida.c 2013-10-11 12:14:56.928543501 +0800
@@ -327,3 +327,47 @@ err:
return -ENOMEM;
}
EXPORT_SYMBOL_GPL(__percpu_ida_init);
+
+/**
+ * percpu_ida_for_each_free - iterate free ids of a pool
+ * @pool: pool to iterate
+ * @fn: interate callback function
+ * @data: parameter for @fn
+ *
+ * Note, this doesn't guarantee iterate all free ids restrictly. Some free
+ * ids might be missed, some might be iterated duplicated, and some might
+ * not be free and iterated.
+ */
+int percpu_ida_for_each_free(struct percpu_ida *pool,
+ int (*fn)(int id, void *data), void *data)
+{
+ unsigned long flags;
+ struct percpu_ida_cpu *remote;
+ unsigned cpu, i, err = 0;
+
+ local_irq_save(flags);
+ for_each_possible_cpu(cpu) {
+ remote = per_cpu_ptr(pool->tag_cpu, cpu);
+ spin_lock(&remote->lock);
+ for (i = 0; i < remote->nr_free; i++) {
+ err = fn(remote->freelist[i], data);
+ if (err)
+ break;
+ }
+ spin_unlock(&remote->lock);
+ if (err)
+ goto out;
+ }
+
+ spin_lock(&pool->lock);
+ for (i = 0; i < pool->nr_free; i++) {
+ err = fn(pool->freelist[i], data);
+ if (err)
+ break;
+ }
+ spin_unlock(&pool->lock);
+out:
+ local_irq_restore(flags);
+ return err;
+}
+EXPORT_SYMBOL_GPL(percpu_ida_for_each_free);
On Fri, Oct 11, 2013 at 03:18:04PM +0800, Shaohua Li wrote:
> Add a new API to iterate free ids. blk-mq-tag will use it.
>
> Signed-off-by: Shaohua Li <[email protected]>
> ---
> include/linux/percpu_ida.h | 3 +++
> lib/percpu_ida.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 47 insertions(+)
>
> Index: master/include/linux/percpu_ida.h
> ===================================================================
> --- master.orig/include/linux/percpu_ida.h 2013-10-11 12:14:56.932543376 +0800
> +++ master/include/linux/percpu_ida.h 2013-10-11 12:14:56.928543501 +0800
> @@ -73,4 +73,7 @@ static inline int percpu_ida_init(struct
> IDA_DEFAULT_PCPU_BATCH_MOVE);
> }
>
> +int percpu_ida_for_each_free(struct percpu_ida *pool,
> + int (*fn)(int id, void *data), void *data);
> +
> #endif /* __PERCPU_IDA_H__ */
> Index: master/lib/percpu_ida.c
> ===================================================================
> --- master.orig/lib/percpu_ida.c 2013-10-11 12:14:56.932543376 +0800
> +++ master/lib/percpu_ida.c 2013-10-11 12:14:56.928543501 +0800
> @@ -327,3 +327,47 @@ err:
> return -ENOMEM;
> }
> EXPORT_SYMBOL_GPL(__percpu_ida_init);
> +
> +/**
> + * percpu_ida_for_each_free - iterate free ids of a pool
> + * @pool: pool to iterate
> + * @fn: interate callback function
> + * @data: parameter for @fn
> + *
> + * Note, this doesn't guarantee iterate all free ids restrictly. Some free
> + * ids might be missed, some might be iterated duplicated, and some might
> + * not be free and iterated.
> + */
> +int percpu_ida_for_each_free(struct percpu_ida *pool,
> + int (*fn)(int id, void *data), void *data)
I'd prefer to make the id parameter unsigned - and use a typedef for the
function pointer argument - but other than that, looks reasonable to me.