Re: [PATCH 7/7] ixgbevf: eliminate duplicate barriers on weakly-ordered archs

From: Timur Tabi
Date: Wed Mar 14 2018 - 01:09:01 EST


On 3/13/18 10:20 PM, Sinan Kaya wrote:
+/* Assumes caller has executed a write barrier to order memory and device
+ * requests.
+ */
static inline void ixgbevf_write_tail(struct ixgbevf_ring *ring, u32 value)
{
- writel(value, ring->tail);
+ writel_relaxed(value, ring->tail);
}

Why not put the wmb() in this function, or just get rid of the wmb() in the rest of the file and keep this as writel? That way, you can avoid the comment and the risk that comes with it.

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