From patchwork Thu Apr 11 11:13:36 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Pattan, Reshma" X-Patchwork-Id: 52646 Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 1FC2F569B; Thu, 11 Apr 2019 13:13:43 +0200 (CEST) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id 12AF15587; Thu, 11 Apr 2019 13:13:40 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Apr 2019 04:13:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,337,1549958400"; d="scan'208";a="141850592" Received: from silpixa00400214.ir.intel.com (HELO silpixa00400214.ger.corp.intel.com) ([10.237.223.195]) by orsmga003.jf.intel.com with ESMTP; 11 Apr 2019 04:13:38 -0700 From: Reshma Pattan To: dev@dpdk.org Cc: Reshma Pattan , david.hunt@intel.com, stable@dpdk.org Date: Thu, 11 Apr 2019 12:13:36 +0100 Message-Id: <20190411111336.2790-1-reshma.pattan@intel.com> X-Mailer: git-send-email 2.17.1 Subject: [dpdk-dev] [PATCH] examples/vm_power_manager: fix overflowed value X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Fix the data type of last_branches, last_branch_misses from unit32_t to uint64_t, and for hits_diff, miss_diff from int to int64_t respectively to fix possible overflow or truncation. Coverity issue: 337677 Fixes: 4b1a631b8a ("examples/vm_power: add oob monitoring functions") CC: david.hunt@intel.com CC: stable@dpdk.org Signed-off-by: Reshma Pattan Reviewed-by: Anatoly Burakov --- examples/vm_power_manager/oob_monitor_x86.c | 23 ++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/examples/vm_power_manager/oob_monitor_x86.c b/examples/vm_power_manager/oob_monitor_x86.c index 589c604e5..ebd96b205 100644 --- a/examples/vm_power_manager/oob_monitor_x86.c +++ b/examples/vm_power_manager/oob_monitor_x86.c @@ -33,10 +33,10 @@ static float apply_policy(int core) { struct core_info *ci; - uint64_t counter; + uint64_t counter = 0; uint64_t branches, branch_misses; - uint32_t last_branches, last_branch_misses; - int hits_diff, miss_diff; + uint64_t last_branches, last_branch_misses; + int64_t hits_diff, miss_diff; float ratio; int ret; @@ -54,6 +54,7 @@ apply_policy(int core) core); branches = counter; + counter = 0; ret = pread(ci->cd[core].msr_fd, &counter, sizeof(counter), IA32_PERFCTR1); if (ret < 0) @@ -66,13 +67,25 @@ apply_policy(int core) ci->cd[core].last_branches = branches; ci->cd[core].last_branch_misses = branch_misses; - hits_diff = (int)branches - (int)last_branches; + /* + * Intentional right shift to make MSB 0 to avoid + * possible signed overflow or truncation. + */ + branches >>= 1; + last_branches >>= 1; + hits_diff = (int64_t)branches - (int64_t)last_branches; if (hits_diff <= 0) { /* Likely a counter overflow condition, skip this round */ return -1.0; } - miss_diff = (int)branch_misses - (int)last_branch_misses; + /* + * Intentional right shift to make MSB 0 to avoid + * possible signed overflow or truncation. + */ + branch_misses >>= 1; + last_branch_misses >>= 1; + miss_diff = (int64_t)branch_misses - (int64_t)last_branch_misses; if (miss_diff <= 0) { /* Likely a counter overflow condition, skip this round */ return -1.0;