Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754191AbdDMRTW (ORCPT ); Thu, 13 Apr 2017 13:19:22 -0400 Received: from mga05.intel.com ([192.55.52.43]:49525 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752537AbdDMRTT (ORCPT ); Thu, 13 Apr 2017 13:19:19 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.37,195,1488873600"; d="scan'208";a="1119130425" From: Keith Busch To: linux-kernel@vger.kernel.org, Thomas Gleixner Cc: Xiaolong Ye , Keith Busch Subject: [PATCH] irq/affinity: Fix extra vecs calculation Date: Thu, 13 Apr 2017 13:28:12 -0400 Message-Id: <1492104492-19943-1-git-send-email-keith.busch@intel.com> X-Mailer: git-send-email 2.5.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1008 Lines: 27 This fixes a math error calculating the extra_vecs. The error assumed only 1 cpu per vector, but the value needs to account for the actual number of cpus per vector in order to get the correct remainder for extra CPU assignment. Fixes: 7bf8222b9bd0 ("irq/affinity: Fix CPU spread for unbalanced nodes") Reported-by: Xiaolong Ye Signed-off-by: Keith Busch --- kernel/irq/affinity.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index dc52911..d052947 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -108,7 +108,7 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) vecs_to_assign = min(vecs_per_node, ncpus); /* Account for rounding errors */ - extra_vecs = ncpus - vecs_to_assign; + extra_vecs = ncpus - vecs_to_assign * (ncpus / vecs_to_assign); for (v = 0; curvec < last_affv && v < vecs_to_assign; curvec++, v++) { -- 2.7.2