From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46B53C433E1 for ; Mon, 17 Aug 2020 11:32:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 292ED204EC for ; Mon, 17 Aug 2020 11:32:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728439AbgHQLcV (ORCPT ); Mon, 17 Aug 2020 07:32:21 -0400 Received: from foss.arm.com ([217.140.110.172]:53486 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727924AbgHQLaX (ORCPT ); Mon, 17 Aug 2020 07:30:23 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 242851396; Mon, 17 Aug 2020 04:30:22 -0700 (PDT) Received: from e113632-lin.cambridge.arm.com (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E3D7C3F66B; Mon, 17 Aug 2020 04:30:20 -0700 (PDT) From: Valentin Schneider To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: mingo@kernel.org, peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, Quentin Perret Subject: [PATCH v6 06/17] sched/debug: Output SD flag names rather than their values Date: Mon, 17 Aug 2020 12:29:52 +0100 Message-Id: <20200817113003.20802-7-valentin.schneider@arm.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200817113003.20802-1-valentin.schneider@arm.com> References: <20200817113003.20802-1-valentin.schneider@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Decoding the output of /proc/sys/kernel/sched_domain/cpu*/domain*/flags has always been somewhat annoying, as one needs to go fetch the bit -> name mapping from the source code itself. This encoding can be saved in a script somewhere, but that isn't safe from flags being added, removed or even shuffled around. What matters for debugging purposes is to get *which* flags are set in a given domain, their associated value is pretty much meaningless. Make the sd flags debug file output flag names. Signed-off-by: Valentin Schneider --- kernel/sched/debug.c | 56 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 55 insertions(+), 1 deletion(-) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 36c54265bb2b..0655524700d2 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -245,6 +245,60 @@ set_table_entry(struct ctl_table *entry, entry->proc_handler = proc_handler; } +static int sd_ctl_doflags(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + unsigned long flags = *(unsigned long *)table->data; + size_t data_size = 0; + size_t len = 0; + char *tmp; + int idx; + + if (write) + return 0; + + for_each_set_bit(idx, &flags, __SD_FLAG_CNT) { + char *name = sd_flag_debug[idx].name; + + /* Name plus whitespace */ + data_size += strlen(name) + 1; + } + + if (*ppos > data_size) { + *lenp = 0; + return 0; + } + + tmp = kcalloc(data_size + 1, sizeof(*tmp), GFP_KERNEL); + if (!tmp) + return -ENOMEM; + + for_each_set_bit(idx, &flags, __SD_FLAG_CNT) { + char *name = sd_flag_debug[idx].name; + + len += snprintf(tmp + len, strlen(name) + 2, "%s ", name); + } + + tmp += *ppos; + len -= *ppos; + + if (len > *lenp) + len = *lenp; + if (len) + memcpy(buffer, tmp, len); + if (len < *lenp) { + ((char *)buffer)[len] = '\n'; + len++; + } + + *lenp = len; + *ppos += len; + + kfree(tmp); + + return 0; +} + static struct ctl_table * sd_alloc_ctl_domain_table(struct sched_domain *sd) { @@ -258,7 +312,7 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd) set_table_entry(&table[2], "busy_factor", &sd->busy_factor, sizeof(int), 0644, proc_dointvec_minmax); set_table_entry(&table[3], "imbalance_pct", &sd->imbalance_pct, sizeof(int), 0644, proc_dointvec_minmax); set_table_entry(&table[4], "cache_nice_tries", &sd->cache_nice_tries, sizeof(int), 0644, proc_dointvec_minmax); - set_table_entry(&table[5], "flags", &sd->flags, sizeof(int), 0444, proc_dointvec_minmax); + set_table_entry(&table[5], "flags", &sd->flags, sizeof(int), 0444, sd_ctl_doflags); set_table_entry(&table[6], "max_newidle_lb_cost", &sd->max_newidle_lb_cost, sizeof(long), 0644, proc_doulongvec_minmax); set_table_entry(&table[7], "name", sd->name, CORENAME_MAX_SIZE, 0444, proc_dostring); /* &table[8] is terminator */ -- 2.27.0