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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,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 09442C433DF for ; Sat, 13 Jun 2020 15:58:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4D10207BC for ; Sat, 13 Jun 2020 15:58:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="t9nAlWRm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726565AbgFMP6N (ORCPT ); Sat, 13 Jun 2020 11:58:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35008 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726538AbgFMP6H (ORCPT ); Sat, 13 Jun 2020 11:58:07 -0400 Received: from mail-ot1-x343.google.com (mail-ot1-x343.google.com [IPv6:2607:f8b0:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D05F6C03E96F for ; Sat, 13 Jun 2020 08:58:05 -0700 (PDT) Received: by mail-ot1-x343.google.com with SMTP id k15so9764046otp.8 for ; Sat, 13 Jun 2020 08:58:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=/AO95lDmp5L2fyl4dZ1p5ig7gAjN+T9cfmBrZBRsxIQ=; b=t9nAlWRm+ySLak8U5pc00ZK27w1/hYYgY833kZDuzAe2lY0sm6ErTexcu/sjJeffiD exGS9mRMBcveqomq0+W66L4NtLP1oOvuVT4vELW1NLx4BkvLKz3ne/Mb9OTkLzWjptiB 6UhwJjwhCFa6JXeRjpWwe7zv7nZJL5ySNtsJmFYK8ZB0UrEXeojAVEupI4sRkukTR0gP pfhv8IfsJiiZoPXfE6T0NnhzkzBtUyudHbGxz7nUxwSYm8h9xGOpVfl/BwizRwOBqpcP nAPafu2V0njxHMSNeoCoBOZ0JEoJj7l9+BmJaBcvSaOrevqnIALHgyMIE7UdSMX1kIMQ YFFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=/AO95lDmp5L2fyl4dZ1p5ig7gAjN+T9cfmBrZBRsxIQ=; b=CDRAhRtIKm1oI+q8HCSeNLUhf0rEuYZ+D4mWy7FBmvNHy8p/+N8ppAi7wxhweyCf45 G1z0WOdkQKuLQHy2TZbJtSgDplSkAvBv+9spb9Xen1fzHYTqcG8RHsVT+aPknn6BOnof ZEVDWVjUC8NWI2f39uB7xaLqr2gmIisi8Wuoj+SHpnTYiB/5bTRQnaBP1eLdWW+C+7Qq e4AHKR3h1LFy/eX5H9qOfkl0wy/3rHzg+8eDLEbV/cqmfXa7hKbkzFL7v27N7SzbpHTP fHPcCx4aGdXYue4349KRcT0kGw716yRQWqeGBaf48lsIhYXu0X+fRE9OBLh5oz+P7QPU TYJQ== X-Gm-Message-State: AOAM531GFeX21FGd/f5gAlpU4WXlHZUuA8fv6OT21VCMJ+3hDsZtUxkp Pg7uSr3816pwK/VqTkmCnaM= X-Google-Smtp-Source: ABdhPJxd+TNWw9aPxibJSqfFnJkzZY9uP3WZG9v97L+fq2e1ifodfK2Ju37F3jaJvW5u/KsBR4ERQw== X-Received: by 2002:a9d:6949:: with SMTP id p9mr15642069oto.7.1592063885245; Sat, 13 Jun 2020 08:58:05 -0700 (PDT) Received: from frodo.hsd1.co.comcast.net ([2601:284:8204:6ba0::aaac]) by smtp.googlemail.com with ESMTPSA id 53sm2105565otv.22.2020.06.13.08.58.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 13 Jun 2020 08:58:04 -0700 (PDT) From: Jim Cromie To: jbaron@akamai.com, linux-kernel@vger.kernel.org, akpm@linuxfoundation.org, gregkh@linuxfoundation.org Cc: linux@rasmusvillemoes.dk, Jim Cromie Subject: [PATCH v2 06/24] dyndbg: fix overcounting of ram used by dyndbg Date: Sat, 13 Jun 2020 09:57:20 -0600 Message-Id: <20200613155738.2249399-7-jim.cromie@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200613155738.2249399-1-jim.cromie@gmail.com> References: <20200613155738.2249399-1-jim.cromie@gmail.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 during dyndbg init, verbose logging prints its ram overhead. It counted strlens of struct _ddebug's 4 string members, in all callsite entries, which would be approximately correct if each had been mallocd. But they are pointers into shared .rodata; for example, all 10 kobject callsites have identical filename, module values. Its best not to count that memory at all, since we cannot know they were linked in because of CONFIG_DYNAMIC_DEBUG=y, and we want to report a number that reflects what ram is saved by deconfiguring it. Also fix wording and size under-reporting of the __dyndbg section. Heres my overhead, on a virtme-run VM on a fedora-31 laptop: dynamic_debug:dynamic_debug_init: 260 modules, 2479 entries \ and 10400 bytes in ddebug tables, 138824 bytes in __dyndbg section --- lib/dynamic_debug.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 66c0bdf06ce7..9b2445507988 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -1017,7 +1017,6 @@ static int __init dynamic_debug_init(void) char *cmdline; int ret = 0; int n = 0, entries = 0, modct = 0; - int verbose_bytes = 0; if (&__start___dyndbg == &__stop___dyndbg) { if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) { @@ -1033,9 +1032,6 @@ static int __init dynamic_debug_init(void) iter_start = iter; for (; iter < __stop___dyndbg; iter++) { entries++; - verbose_bytes += strlen(iter->modname) + strlen(iter->function) - + strlen(iter->filename) + strlen(iter->format); - if (strcmp(modname, iter->modname)) { modct++; ret = ddebug_add_module(iter_start, n, modname); @@ -1052,9 +1048,9 @@ static int __init dynamic_debug_init(void) goto out_err; ddebug_init_success = 1; - vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in (readonly) verbose section\n", + vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in __dyndbg section\n", modct, entries, (int)(modct * sizeof(struct ddebug_table)), - verbose_bytes + (int)(__stop___dyndbg - __start___dyndbg)); + (int)(entries * sizeof(struct _ddebug))); /* apply ddebug_query boot param, dont unload tables on err */ if (ddebug_setup_string[0] != '\0') { -- 2.26.2