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=unavailable 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 6BBCDC433E1 for ; Sat, 13 Jun 2020 15:58:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A1A520789 for ; Sat, 13 Jun 2020 15:58:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="M2TJdnrs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726657AbgFMP6f (ORCPT ); Sat, 13 Jun 2020 11:58:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726631AbgFMP60 (ORCPT ); Sat, 13 Jun 2020 11:58:26 -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 1BF47C08C5C1; Sat, 13 Jun 2020 08:58:26 -0700 (PDT) Received: by mail-ot1-x343.google.com with SMTP id t6so9746100otk.9; Sat, 13 Jun 2020 08:58:26 -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=AU7c+PgpMF6te0CQ1BmL/sHbcOGozgQf6DVP7H/JO0k=; b=M2TJdnrsf/njaeRrcI4jZj6OY+iKoxU0C/stcsR/jmUotSBI0b3yye24DFEO7s+iwd g+yrADzZwV9qSS+3rX3MqwuffjEeXa+Vl0sfdrg2Cp63vwGB+AR5W/c7YNz1Lu58ipEP Of0fSm6rGWMIol++gAy3cB4aWju/pwAasE8zCH1xKyUURsaEZh4wIGblIaJvoPqivhTh fhLPLyOSXoMP4w3GtPhQiuTr+gBy9w1w4TXYe+JlYIeEspwplGpThW7x6gRLt44Ofkoe GHD27yXsV/PREs3+j2PfSbDVrHfl7DrZqtuz0TEfKR3D/Thb+rzSSlytmk6WEsz+qruK aw8g== 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=AU7c+PgpMF6te0CQ1BmL/sHbcOGozgQf6DVP7H/JO0k=; b=e+NQpmWn2r2+rhI3/N+2LWS9ZJZvl4XmQDo2JwlVleinh7LJE2j6h3sGhVfMnvuWbe 6UjCkqDT5gMf/y8YtE2A+8HgCpFwdtxfmQfAbDuh5NtYs5npyes7cRUe287NRj8fnHIL UllSzxADaj7laWGEhz0GQp50uebxoFxsPpdHeQSOkCKpG1CSgiqm0HY8BHbKT6e5xFjy zybMPCGh6U5IAjEVcYb4/LvVkUEltBRYHvNoFCic/L2xNMvzUFPtGLNbV4mqMdaKzV7t BGO/jOKUzRk2FL0qW6b+mog/giggryifAiXVs6D3NthZ0D8aesYyR7UDFVSCkbZkO5yn 6xIA== X-Gm-Message-State: AOAM5338SwX7Or1ubFydjiSlxsZQfAFqytM7FtObs7wgKpibGsCt/vJH gb3yAAWuKf4WV/WrkjRMGfY= X-Google-Smtp-Source: ABdhPJwEiBOkJ7LJx5no1mEA38zAePPgCNACVbNpbKBzFmhlcBoRcUwVhttivOQMs+5m39qEqsQZ4w== X-Received: by 2002:a05:6830:3104:: with SMTP id b4mr15390105ots.192.1592063905453; Sat, 13 Jun 2020 08:58:25 -0700 (PDT) Received: from frodo.hsd1.co.comcast.net ([2601:284:8204:6ba0::aaac]) by smtp.googlemail.com with ESMTPSA id 53sm2105565otv.22.2020.06.13.08.58.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 13 Jun 2020 08:58:24 -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 , Jonathan Corbet , Andrew Morton , Petr Mladek , Will Deacon , Orson Zhai , linux-doc@vger.kernel.org Subject: [PATCH v2 17/24] dyndbg: add user-flag, negating-flags, and filtering on flags Date: Sat, 13 Jun 2020 09:57:31 -0600 Message-Id: <20200613155738.2249399-18-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 1. Add a user-flag [u] which works like the [pfmlt] flags, but has no effect on callsite behavior; it allows incremental marking of arbitrary sets of callsites. 2. Add [PFMLTU] flags, which negate their counterparts; P===!p etc. And in ddebug_read_flags(): current code does: [pfmltu_] -> flags copy it to: [PFMLTU_] -> mask also disallow both of a pair: ie no 'pP', no true & false. 3. Add filtering ops into ddebug_change(), right after all the callsite-property selections are complete. These filter on the callsite's current flagstate before applying modflags. Why ? The 'u' flag lets the user assemble an arbitary set of callsites. Then using filter flags, user can activate the 'u' set. #> echo 'file foo.c +u; file bar.c +u' > control # and repeat #> echo 'u+p' > control Using negating-flags in your filter-flags, you can completely specify the matching flagstate; not just required flags, but also prohibited flags. The user flag isn't strictly needed, but with it you can avoid using [fmlt] flags for marking, which would alter logging when enabled. --- .../admin-guide/dynamic-debug-howto.rst | 31 ++++++++++++++++--- include/linux/dynamic_debug.h | 1 + lib/dynamic_debug.c | 31 ++++++++++++++----- 3 files changed, 51 insertions(+), 12 deletions(-) diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst index 4f343e6036f5..45d3adf889ba 100644 --- a/Documentation/admin-guide/dynamic-debug-howto.rst +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -238,16 +238,39 @@ The flags are:: l Include line number in the printed message m Include module name in the printed message t Include thread ID in messages not generated from interrupt context + u user flag, to mark callsites into a group _ No flags are set. (Or'd with others on input) -For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only ``p`` flag -have meaning, other flags ignored. +Additionally, the flag-chars ``[pflmtu]`` have negating flag-chars +``[PFMLTU]``, which invert the meanings above. Their use follows. + +Using Filters:: + +Filter-flags specify an optional additional selector on pr_debug +callsites; with them you can compose an arbitrary set of callsites, by +iteratively marking them with ``+u``, then enabling them all with +``u+p``. You can also use ``fmlt`` flags for this, unless the format +changes are inconvenient. + +Filters can also contain the negating flags, like ``UF``, which select +only callsites with ``u`` and ``f`` cleared. + +Flagsets cannot contain ``pP`` etc, a flag cannot be true and false. + +modflags containing upper-case flags is reserved/undefined for now. +inverted-flags are currently ignored, usage gets trickier if given +``-pXy``, it should leave x set. + +Notes:: + +For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only +``p`` flag has meaning, other flags are ignored. For display, the flags are preceded by ``=`` (mnemonic: what the flags are currently equal to). -Note the regexp ``^[-+=][flmpt_]+$`` matches a flags specification. -To clear all flags at once, use ``=_`` or ``-flmpt``. +Note the regexp ``^[-+=][flmptu_]+$`` matches a flags specification. +To clear all flags at once, use ``=_`` or ``-flmptu``. Debug messages during Boot Process diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index aa9ff9e1c0b3..59960a8dd9f9 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -32,6 +32,7 @@ struct _ddebug { #define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2) #define _DPRINTK_FLAGS_INCL_LINENO (1<<3) #define _DPRINTK_FLAGS_INCL_TID (1<<4) +#define _DPRINTK_FLAGS_USR (1<<5) #if defined DEBUG #define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT #else diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index b3c262c009d2..b02cde1cfc2f 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -83,13 +83,14 @@ static inline const char *trim_prefix(const char *path) return path + skip; } -static struct { unsigned flag:8; char opt_char; } opt_array[] = { - { _DPRINTK_FLAGS_PRINT, 'p' }, - { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, - { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, - { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, - { _DPRINTK_FLAGS_INCL_TID, 't' }, - { _DPRINTK_FLAGS_NONE, '_' }, +static struct { unsigned flag:8; char opt_char, not_char; } opt_array[] = { + { _DPRINTK_FLAGS_PRINT, 'p', 'P' }, + { _DPRINTK_FLAGS_INCL_MODNAME, 'm', 'M' }, + { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f', 'F' }, + { _DPRINTK_FLAGS_INCL_LINENO, 'l', 'L' }, + { _DPRINTK_FLAGS_INCL_TID, 't', 'T' }, + { _DPRINTK_FLAGS_NONE, '_', '_' }, + { _DPRINTK_FLAGS_USR, 'u', 'U' }, }; struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; }; @@ -195,6 +196,13 @@ static int ddebug_change(const struct ddebug_query *query, dp->lineno > query->last_lineno) continue; + /* filter for required flags */ + if ((dp->flags & filter->flags) != filter->flags) + continue; + /* filter on prohibited bits */ + if ((~dp->flags & filter->mask) != filter->mask) + continue; + nfound++; newflags = (dp->flags & mods->mask) | mods->flags; @@ -428,10 +436,17 @@ static int ddebug_read_flags(const char *str, struct flagsettings *f) if (*str == opt_array[i].opt_char) { f->flags |= opt_array[i].flag; break; + } else if (*str == opt_array[i].not_char) { + f->mask |= opt_array[i].flag; + break; } } if (i < 0) { - pr_err("unknown flag '%c' in \"%s\"\n", *str, str); + pr_err("unknown flag '%c'", *str); + return -EINVAL; + } + if (f->flags & f->mask) { + pr_err("flag '%c' conflicts with previous\n", *str); return -EINVAL; } } -- 2.26.2