From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout05.his.huawei.com (canpmsgout05.his.huawei.com [113.46.200.220]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A9E5137C936; Sat, 1 Aug 2026 09:24:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.220 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785576285; cv=none; b=fsJGDw8yIAeffM8W7yHRMOxKoxOqIuP4ZzY65VfrU1t0OHCgsukutAGlhBLZWkx69VolimMaWT53c36mJkYMomEZmiWF4r6NbSW88jO45iGr5YL+rlqC8i31Gyv2kxZG1dLETNECyKFj+RWdbuAxB0RPZQqEPVdDPd90QU/X0tg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785576285; c=relaxed/simple; bh=Li7clJt35PKhW/MR0mWiUo7TpVdq+Qa0flOc6RBM1C0=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=kgi0xrESBoBNFGqUajQCWPaaJYWWAoOvUhxtbaqqNMwoEFUw8N2CN9SJpESCIb3nVDYlTvOw+OpHW6sfnM6FS63mcb3s9FZQ3HjfQ1BDpLVwFLtBjUPSGZ6ym8kwSDb2NqpZHD306ZMEqTOYzs7tT8Xc0VcdBMh36Y5kv/mw0xk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=KNovAnK+; arc=none smtp.client-ip=113.46.200.220 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="KNovAnK+" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=d1ialI7mCM+y+NO3FOOExFE5h1pMpOlMrSsDH4xPxr8=; b=KNovAnK+kP8sj0TWTZnykcB17a+JrdfN2xN/b42bCK41uJNVDOkuc7zMwIRNYctd0obKW/Rlw YK7q1Mu2ETaWlGcNses/Glbz3HJUbQmqj3esHFXPeWe01u8W6Mr1UtrRNRdX6wwEJsF3zX7Pl/D wEtTmMv8YvkNDiC+xF4eltc= Received: from mail.maildlp.com (unknown [172.19.162.223]) by canpmsgout05.his.huawei.com (SkyGuard) with ESMTPS id 4hBy2J6tgkz12LDF; Sat, 1 Aug 2026 17:15:04 +0800 (CST) Received: from kwepemo100012.china.huawei.com (unknown [7.202.195.139]) by mail.maildlp.com (Postfix) with ESMTPS id 1AF8640561; Sat, 1 Aug 2026 17:24:33 +0800 (CST) Received: from huawei.com (10.50.163.32) by kwepemo100012.china.huawei.com (7.202.195.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Sat, 1 Aug 2026 17:24:32 +0800 From: Yifan Wu To: , , , , , , , , , , , , , , CC: , , , , Subject: [PATCH v4 3/3] selftests/resctrl: Enable dynamic management of IMC counters via linked list Date: Sat, 1 Aug 2026 17:24:29 +0800 Message-ID: <20260801092429.533956-4-wuyifan50@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20260801092429.533956-1-wuyifan50@huawei.com> References: <20260801092429.533956-1-wuyifan50@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To kwepemo100012.china.huawei.com (7.202.195.139) Remove the static array and the count and upper limit checks during initialization, allowing the system to dynamically use all available IMC counters detected by hardware. Reviewed-by: Reinette Chatre Signed-off-by: Yifan Wu --- tools/testing/selftests/resctrl/resctrl_val.c | 94 ++++++++----------- 1 file changed, 41 insertions(+), 53 deletions(-) diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c index f4111da26fc2..7e7d0f9cc249 100644 --- a/tools/testing/selftests/resctrl/resctrl_val.c +++ b/tools/testing/selftests/resctrl/resctrl_val.c @@ -14,7 +14,6 @@ #define READ_FILE_NAME "cas_count_read" #define DYN_PMU_PATH "/sys/bus/event_source/devices" #define SCALE 0.00006103515625 -#define MAX_IMCS 40 #define MAX_TOKENS 5 #define CON_MBM_LOCAL_BYTES_PATH \ @@ -37,8 +36,6 @@ struct imc_counter_config { }; static char mbm_total_path[1024]; -static int imcs; -static struct imc_counter_config imc_counters_config[MAX_IMCS]; LIST_HEAD(imc_counters_list); static const struct resctrl_test *current_test; @@ -107,12 +104,11 @@ static int open_perf_read_event(int cpu_no, struct imc_counter_config *imc_count return 0; } -static int parse_imc_read_bw_events(char *imc_dir, unsigned int type, - unsigned int *count) +static int parse_imc_read_bw_events(char *imc_dir, unsigned int type) { char imc_events_dir[PATH_MAX], imc_counter_cfg[PATH_MAX]; struct imc_counter_config *imc_counter; - unsigned int orig_count = *count; + bool found_event = false; char cas_count_cfg[1024]; struct dirent *ep; int path_len; @@ -162,23 +158,18 @@ static int parse_imc_read_bw_events(char *imc_dir, unsigned int type, ksft_perror("Could not get iMC cas count read"); goto out_close; } - if (*count >= MAX_IMCS) { - ksft_print_msg("Maximum iMC count exceeded\n"); - goto out_close; - } imc_counter = calloc(1, sizeof(*imc_counter)); if (!imc_counter) { ksft_perror("Unable to allocate memory for iMC counters"); goto out_close; } - imc_counters_config[*count].type = type; - get_read_event_and_umask(cas_count_cfg, &imc_counters_config[*count]); - /* Do not fail after incrementing *count. */ - *count += 1; + imc_counter->type = type; + get_read_event_and_umask(cas_count_cfg, imc_counter); list_add(&imc_counter->entry, &imc_counters_list); + found_event = true; } - if (*count == orig_count) { + if (!found_event) { ksft_print_msg("Unable to find events in %s\n", imc_events_dir); goto out_close; } @@ -193,7 +184,7 @@ static int parse_imc_read_bw_events(char *imc_dir, unsigned int type, } /* Get type and config of an iMC counter's read event. */ -static int read_from_imc_dir(char *imc_dir, unsigned int *count) +static int read_from_imc_dir(char *imc_dir) { char imc_counter_type[PATH_MAX]; unsigned int type; @@ -221,7 +212,7 @@ static int read_from_imc_dir(char *imc_dir, unsigned int *count) ksft_perror("Could not get iMC type"); return -1; } - ret = parse_imc_read_bw_events(imc_dir, type, count); + ret = parse_imc_read_bw_events(imc_dir, type); if (ret) { ksft_print_msg("Unable to parse bandwidth event and umask\n"); return ret; @@ -231,21 +222,18 @@ static int read_from_imc_dir(char *imc_dir, unsigned int *count) } /* - * A system can have 'n' number of iMC (Integrated Memory Controller) - * counters, get that 'n'. Discover the properties of the available - * counters in support of needed performance measurement via perf. - * For each iMC counter get it's type and config. Also obtain each - * counter's event and umask for the memory read events that will be - * measured. + * Discover the properties of the available iMC (Integrated Memory Controller) + * counters in support of needed performance measurement via perf. For each iMC + * counter get it's type and config. Also obtain each counter's event and umask + * for the memory read events that will be measured. * - * Enumerate all these details into an array of structures. + * Enumerate all these details into a linked list of structures. * * Return: >= 0 on success. < 0 on failure. */ -static int num_of_imcs(void) +static int enumerate_imcs(void) { char imc_dir[512], *temp; - unsigned int count = 0; struct dirent *ep; int ret; DIR *dp; @@ -274,7 +262,7 @@ static int num_of_imcs(void) if (temp[0] >= '0' && temp[0] <= '9') { sprintf(imc_dir, "%s/%s/", DYN_PMU_PATH, ep->d_name); - ret = read_from_imc_dir(imc_dir, &count); + ret = read_from_imc_dir(imc_dir); if (ret) { closedir(dp); @@ -283,7 +271,7 @@ static int num_of_imcs(void) } } closedir(dp); - if (count == 0) { + if (list_empty(&imc_counters_list)) { ksft_print_msg("Unable to find iMC counters\n"); return -1; @@ -294,20 +282,21 @@ static int num_of_imcs(void) return -1; } - return count; + return 0; } int initialize_read_mem_bw_imc(void) { - int imc; + struct imc_counter_config *imc_counter; + int ret; - imcs = num_of_imcs(); - if (imcs <= 0) - return imcs; + ret = enumerate_imcs(); + if (ret < 0) + return ret; /* Initialize perf_event_attr structures for all iMC's */ - for (imc = 0; imc < imcs; imc++) - read_mem_bw_initialize_perf_event_attr(&imc_counters_config[imc]); + list_for_each_entry(imc_counter, &imc_counters_list, entry) + read_mem_bw_initialize_perf_event_attr(imc_counter); return 0; } @@ -324,11 +313,11 @@ void cleanup_read_mem_bw_imc(void) static void perf_close_imc_read_mem_bw(void) { - int mc; + struct imc_counter_config *imc_counter; - for (mc = 0; mc < imcs; mc++) { - if (imc_counters_config[mc].fd != -1) - close(imc_counters_config[mc].fd); + list_for_each_entry(imc_counter, &imc_counters_list, entry) { + if (imc_counter->fd != -1) + close(imc_counter->fd); } } @@ -340,13 +329,14 @@ static void perf_close_imc_read_mem_bw(void) */ static int perf_open_imc_read_mem_bw(int cpu_no) { - int imc, ret; + struct imc_counter_config *imc_counter; + int ret; - for (imc = 0; imc < imcs; imc++) - imc_counters_config[imc].fd = -1; + list_for_each_entry(imc_counter, &imc_counters_list, entry) + imc_counter->fd = -1; - for (imc = 0; imc < imcs; imc++) { - ret = open_perf_read_event(cpu_no, &imc_counters_config[imc]); + list_for_each_entry(imc_counter, &imc_counters_list, entry) { + ret = open_perf_read_event(cpu_no, imc_counter); if (ret) goto close_fds; } @@ -366,16 +356,16 @@ static int perf_open_imc_read_mem_bw(int cpu_no) */ static void do_imc_read_mem_bw_test(void) { - int imc; + struct imc_counter_config *imc_counter; - for (imc = 0; imc < imcs; imc++) - read_mem_bw_ioctl_perf_event_ioc_reset_enable(&imc_counters_config[imc]); + list_for_each_entry(imc_counter, &imc_counters_list, entry) + read_mem_bw_ioctl_perf_event_ioc_reset_enable(imc_counter); sleep(1); /* Stop counters after a second to get results. */ - for (imc = 0; imc < imcs; imc++) - read_mem_bw_ioctl_perf_event_ioc_disable(&imc_counters_config[imc]); + list_for_each_entry(imc_counter, &imc_counters_list, entry) + read_mem_bw_ioctl_perf_event_ioc_disable(imc_counter); } /* @@ -390,17 +380,15 @@ static void do_imc_read_mem_bw_test(void) static int get_read_mem_bw_imc(float *bw_imc) { float reads = 0, of_mul_read = 1; - int imc; + struct imc_counter_config *r; /* * Log read event values from all iMC counters into * struct imc_counter_config. * Take overflow into consideration before calculating total bandwidth. */ - for (imc = 0; imc < imcs; imc++) { + list_for_each_entry(r, &imc_counters_list, entry) { struct membw_read_format measurement; - struct imc_counter_config *r = - &imc_counters_config[imc]; if (read(r->fd, &measurement, sizeof(measurement)) == -1) { ksft_perror("Couldn't get read bandwidth through iMC"); -- 2.33.0