From: Jason Wang <jasowang@redhat.com>
Date: Wed, 17 May 2017 12:14:39 +0800
Subject: ptr_ring: introduce batch dequeuing
Patch-mainline: v4.13-rc1
Git-commit: 728fc8d5532b956f9c4b48dff0577fb722251343
References: bsc#1109837
This patch introduce a batched version of consuming, consumer can
dequeue more than one pointers from the ring at a time. We don't care
about the reorder of reading here so no need for compiler barrier.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/linux/ptr_ring.h | 65 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 65 insertions(+)
--- a/include/linux/ptr_ring.h
+++ b/include/linux/ptr_ring.h
@@ -278,6 +278,22 @@ static inline void *__ptr_ring_consume(s
return ptr;
}
+static inline int __ptr_ring_consume_batched(struct ptr_ring *r,
+ void **array, int n)
+{
+ void *ptr;
+ int i;
+
+ for (i = 0; i < n; i++) {
+ ptr = __ptr_ring_consume(r);
+ if (!ptr)
+ break;
+ array[i] = ptr;
+ }
+
+ return i;
+}
+
/*
* Note: resize (below) nests producer lock within consumer lock, so if you
* call this in interrupt or BH context, you must disable interrupts/BH when
@@ -328,6 +344,55 @@ static inline void *ptr_ring_consume_bh(
return ptr;
}
+static inline int ptr_ring_consume_batched(struct ptr_ring *r,
+ void **array, int n)
+{
+ int ret;
+
+ spin_lock(&r->consumer_lock);
+ ret = __ptr_ring_consume_batched(r, array, n);
+ spin_unlock(&r->consumer_lock);
+
+ return ret;
+}
+
+static inline int ptr_ring_consume_batched_irq(struct ptr_ring *r,
+ void **array, int n)
+{
+ int ret;
+
+ spin_lock_irq(&r->consumer_lock);
+ ret = __ptr_ring_consume_batched(r, array, n);
+ spin_unlock_irq(&r->consumer_lock);
+
+ return ret;
+}
+
+static inline int ptr_ring_consume_batched_any(struct ptr_ring *r,
+ void **array, int n)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&r->consumer_lock, flags);
+ ret = __ptr_ring_consume_batched(r, array, n);
+ spin_unlock_irqrestore(&r->consumer_lock, flags);
+
+ return ret;
+}
+
+static inline int ptr_ring_consume_batched_bh(struct ptr_ring *r,
+ void **array, int n)
+{
+ int ret;
+
+ spin_lock_bh(&r->consumer_lock);
+ ret = __ptr_ring_consume_batched(r, array, n);
+ spin_unlock_bh(&r->consumer_lock);
+
+ return ret;
+}
+
/* Cast to structure type and call a function without discarding from FIFO.
* Function must return a value.
* Callers must take consumer_lock.