From patchwork Tue Oct 20 23:51:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fenghua Yu X-Patchwork-Id: 11848037 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4C99E14B4 for ; Tue, 20 Oct 2020 23:51:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3657D2225F for ; Tue, 20 Oct 2020 23:51:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439410AbgJTXvm (ORCPT ); Tue, 20 Oct 2020 19:51:42 -0400 Received: from mga07.intel.com ([134.134.136.100]:11170 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2439408AbgJTXvk (ORCPT ); Tue, 20 Oct 2020 19:51:40 -0400 IronPort-SDR: 2NjDcXx9c9YXvtHvLx8i1aD12V4eWTQxBmnDcL35kDfVldTyovEgIUO4jRWBRObaDt/Je54gaa ZynMcvvHCpnQ== X-IronPort-AV: E=McAfee;i="6000,8403,9780"; a="231486373" X-IronPort-AV: E=Sophos;i="5.77,399,1596524400"; d="scan'208";a="231486373" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2020 16:51:34 -0700 IronPort-SDR: UTZd5P1nura7GF2szGIcSqWtC0LeH0+kaKvklBOW/iLDlXUKBGDbyZuIL6tyihGebpSjc8Rmo4 8/QQ2NB/JVcw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,399,1596524400"; d="scan'208";a="320833905" Received: from otcwcpicx6.sc.intel.com ([172.25.55.29]) by orsmga006.jf.intel.com with ESMTP; 20 Oct 2020 16:51:33 -0700 From: Fenghua Yu To: "Shuah Khan" , "Reinette Chatre" , "Tony Luck" , "Babu Moger" , "James Morse" , "Borislav Petkov" , "Thomas Gleixner" , "Ravi V Shankar" Cc: "linux-kselftest" , "linux-kernel" , Fenghua Yu Subject: [PATCH v3 21/21] selftests/resctrl: Don't use global variable for capacity bitmask (CBM) Date: Tue, 20 Oct 2020 23:51:26 +0000 Message-Id: <20201020235126.1871815-22-fenghua.yu@intel.com> X-Mailer: git-send-email 2.29.0 In-Reply-To: <20201020235126.1871815-1-fenghua.yu@intel.com> References: <20201020235126.1871815-1-fenghua.yu@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Reinette reported following compilation issue on Fedora 32, gcc version 10.1.1 /usr/bin/ld: cmt_test.o:/cmt_test.c:19: multiple definition of `cbm_mask'; cat_test.o:/cat_test.c:20: first defined here /usr/bin/ld: resctrlfs.o:/resctrlfs.c:52: multiple definition of `cbm_mask'; cat_test.o:/cat_test.c:20: first defined here Compiler throws an error because cbm_mask is defined as a global variable in three different .c files, namely resctrlfs.c, cat_test.c and cmt_test.c. cbm_mask is a global variable that is supposed to hold the capacity bitmask (CBM) value read from resctrl/info directory. This is done by get_cbm_mask() function which then sets the global variable. To reduce the use of global variables (thereby improving readability and maintainability) change get_cbm_mask() implementation such that it now accepts a reference to a string. Upon success, get_cbm_mask() populates the string with CBM value read from resctrl/info directory and returns 0 and on failure, returns -1. Please note that this change to get_cbm_mask() fixes the issue reported by Reinette because cbm_mask isn't a global variable anymore. Fixes: 78941183d1b15 ("selftests/resctrl: Add Cache QoS Monitoring (CQM) selftest") Fixes: 790bf585b0eee ("selftests/resctrl: Add Cache Allocation Technology (CAT) selftest") Reported-by: Reinette Chatre Signed-off-by: Fenghua Yu --- tools/testing/selftests/resctrl/cat_test.c | 5 ++--- tools/testing/selftests/resctrl/cmt_test.c | 5 ++--- tools/testing/selftests/resctrl/resctrl.h | 2 +- tools/testing/selftests/resctrl/resctrlfs.c | 10 +++++----- 4 files changed, 10 insertions(+), 12 deletions(-) diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index e518f8f7b4d8..60b31b85b484 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -17,8 +17,6 @@ #define MAX_DIFF_PERCENT 4 #define MAX_DIFF 1000000 -char cbm_mask[256]; - /* * Change schemata. Write schemata to specified * con_mon grp, mon_grp in resctrl FS. @@ -120,6 +118,7 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) { unsigned long l_mask, l_mask_1, long_mask, cache_size; int ret, pipefd[2], sibling_cpu_no, count_of_bits; + char cbm_mask[256]; char pipe_message; pid_t bm_pid; @@ -130,7 +129,7 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) return ret; /* Get default cbm mask for L3/L2 cache */ - ret = get_cbm_mask(cache_type); + ret = get_cbm_mask(cache_type, cbm_mask); if (ret) return ret; diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c index f0cb441cca9f..0bee3e6480a3 100644 --- a/tools/testing/selftests/resctrl/cmt_test.c +++ b/tools/testing/selftests/resctrl/cmt_test.c @@ -16,8 +16,6 @@ #define MAX_DIFF 2000000 #define MAX_DIFF_PERCENT 15 -char cbm_mask[256]; - static int cmt_setup(int num, ...) { struct resctrl_val_param *p; @@ -112,6 +110,7 @@ int cmt_resctrl_val(int cpu_no, int n, char **benchmark_cmd) { int ret, mum_resctrlfs, count_of_bits; unsigned long long_mask, cache_size; + char cbm_mask[256]; cache_size = 0; mum_resctrlfs = 1; @@ -120,7 +119,7 @@ int cmt_resctrl_val(int cpu_no, int n, char **benchmark_cmd) if (ret) return ret; - ret = get_cbm_mask("L3"); + ret = get_cbm_mask("L3", cbm_mask); if (ret) return ret; diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h index 65ca24bf3eac..2546435864d0 100644 --- a/tools/testing/selftests/resctrl/resctrl.h +++ b/tools/testing/selftests/resctrl/resctrl.h @@ -96,7 +96,7 @@ void tests_cleanup(void); void mbm_test_cleanup(void); int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd); void mba_test_cleanup(void); -int get_cbm_mask(char *cache_type); +int get_cbm_mask(char *cache_type, char *cbm_mask); int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size); void ctrlc_handler(int signum, siginfo_t *info, void *ptr); int cat_val(struct resctrl_val_param *param); diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index 21281fd895b7..a07118e01590 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -49,8 +49,6 @@ static int find_resctrl_mount(char *buffer) return -ENOENT; } -char cbm_mask[256]; - /* * remount_resctrlfs - Remount resctrl FS at /sys/fs/resctrl * @mum_resctrlfs: Should the resctrl FS be remounted? @@ -208,16 +206,18 @@ int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size) /* * get_cbm_mask - Get cbm mask for given cache * @cache_type: Cache level L2/L3 - * - * Mask is stored in cbm_mask which is global variable. + * @cbm_mask: cbm_mask returned as a string * * Return: = 0 on success, < 0 on failure. */ -int get_cbm_mask(char *cache_type) +int get_cbm_mask(char *cache_type, char *cbm_mask) { char cbm_mask_path[1024]; FILE *fp; + if (!cbm_mask) + return -1; + sprintf(cbm_mask_path, "%s/%s/cbm_mask", CBM_MASK_PATH, cache_type); fp = fopen(cbm_mask_path, "r");