From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhen Lei Subject: [PATCH 2/7] iommu/iova: cut down judgement times Date: Wed, 22 Mar 2017 14:27:42 +0800 Message-ID: <1490164067-12552-3-git-send-email-thunder.leizhen@huawei.com> References: <1490164067-12552-1-git-send-email-thunder.leizhen@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1490164067-12552-1-git-send-email-thunder.leizhen-hv44wF8Li93QT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Joerg Roedel , iommu , Robin Murphy , David Woodhouse , Sudeep Dutt , Ashutosh Dixit , linux-kernel Cc: Xinwei Hu , Zhen Lei , Zefan Li , Hanjun Guo , Tianhong Ding List-Id: iommu@lists.linux-foundation.org Below judgement can only be satisfied at the last time, which produced 2N judgements(suppose N times failed, 0 or 1 time successed) in vain. if ((pfn >= iova->pfn_lo) && (pfn <= iova->pfn_hi)) { return iova; } Signed-off-by: Zhen Lei --- drivers/iommu/iova.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 8ba8b496..1c49969 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -312,15 +312,12 @@ private_find_iova(struct iova_domain *iovad, unsigned long pfn) while (node) { struct iova *iova = rb_entry(node, struct iova, node); - /* If pfn falls within iova's range, return iova */ - if ((pfn >= iova->pfn_lo) && (pfn <= iova->pfn_hi)) { - return iova; - } - if (pfn < iova->pfn_lo) node = node->rb_left; - else if (pfn > iova->pfn_lo) + else if (pfn > iova->pfn_hi) node = node->rb_right; + else + return iova; /* pfn falls within iova's range */ } return NULL; -- 2.5.0