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=-9.6 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,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 91A90C433DF for ; Fri, 5 Jun 2020 16:28:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 671F820820 for ; Fri, 5 Jun 2020 16:28:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="a8GghHbX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726575AbgFEQ2N (ORCPT ); Fri, 5 Jun 2020 12:28:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41144 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728610AbgFEQ2K (ORCPT ); Fri, 5 Jun 2020 12:28:10 -0400 Received: from mail-ot1-x341.google.com (mail-ot1-x341.google.com [IPv6:2607:f8b0:4864:20::341]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9460C08C5C2; Fri, 5 Jun 2020 09:28:09 -0700 (PDT) Received: by mail-ot1-x341.google.com with SMTP id v17so8090797ote.0; Fri, 05 Jun 2020 09:28:09 -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=PgeKZicaAAcFCU8vOGCrkdV6kskck/MCatzZXUFR2Ow=; b=a8GghHbX3HKW/WPLW5e2787BuST6oAIuhvdBzc5DShgXgWPkTpV0KW9/jBtnI4P92R N3nhNG6K5Tsi+qLyMJ24H3JNEkHafYk88pw9vSB5pQgICp7IqtR0Oxu4iJxD43nsXahF 4lQwRDDHyTvlHx0bjaDl03CvVgDVznLCIRljNcfE3rREdsvIi7bQ1leihSU54YQYBp6f XnB4FC8UfU+IGnBUTrOGxrLsli2wQCiHRyeORG6nMYaNK9outQVIUYUgQ+f79kQZug5v 5pXiLyYR6YmbNnMZALqRkZhbb8qaaISqfvjU20Hs606P1rdEKQTnbSkDACzqY0NwGA/9 k60g== 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=PgeKZicaAAcFCU8vOGCrkdV6kskck/MCatzZXUFR2Ow=; b=NG1TE0GB9RkZVL5rU0MfjUYZCtvfGS4NbnM+elzVLmmSZq2M02S1Pox85qqqhwAOtW t5u7T+n77BXKwzFwcuKKyS/hRyt/eUVo45tpfL8Zl5mUqDJ7Puu8y0w9fByn5SS/pgeV pFSA8gdTHEQdbhtzDJs9Xfc3+RTQjWh6/EZmac8Kpx1I8TRDbb8GjQzW/a3PEFZFwX87 i+Bg/P4OR2apaC38BuK+4TBKnS8FJyHEPSptTaojh77hS8HU+iUEJpmagzdrbG1gsDqk Yn/8cpLcY7bGK8Nw3w/05ejMySxt8jrUJpqHpU8XMd6KOR+f9gvnr7iOczJRUeVSf6th kmaQ== X-Gm-Message-State: AOAM531Zsw8wPsMjkGwsj1Nr8Y5kpnceRgOnKVCwiHHzPccl81semRzx TGdJq+/VMgN+XrKwKIJb69g= X-Google-Smtp-Source: ABdhPJwEszlzeuWUKFyvbzZeD5OBR2SgU+byFlG9gnPBADRG9daA0Hc7HEsJ9cxmZrIab0GyDtBnew== X-Received: by 2002:a05:6830:54:: with SMTP id d20mr8624037otp.281.1591374489194; Fri, 05 Jun 2020 09:28:09 -0700 (PDT) Received: from frodo.hsd1.co.comcast.net ([2601:284:8204:6ba0::aaac]) by smtp.googlemail.com with ESMTPSA id z13sm813894ooa.28.2020.06.05.09.28.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 05 Jun 2020 09:28:08 -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 , Will Deacon , linux-doc@vger.kernel.org Subject: [PATCH 15/16] dyndbg: add user-flag, negating-flags, and filtering on flags Date: Fri, 5 Jun 2020 10:26:44 -0600 Message-Id: <20200605162645.289174-16-jim.cromie@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200605162645.289174-1-jim.cromie@gmail.com> References: <20200605162645.289174-1-jim.cromie@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@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 new user flag facilitates batching of changes. By marking individual callsites with 'u', a user can compose an arbitrary set of changes, then activate them together by filtering on 'u': #> echo 'file foo.c +u; file bar.c +u' > control #> echo 'u+p' > control The user flag isn't strictly needed, but with it you can avoid using [fmlt] flags for marking, which would alter logging when enabled. The negating flags allow filtering on either 0/1 for each flag. Signed-off-by: Jim Cromie --- .../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 250ab30e2080..26a19f511afa 100644 --- a/Documentation/admin-guide/dynamic-debug-howto.rst +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -233,16 +233,39 @@ 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 802480ea8708..a5d76f8f6b40 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 f0c0c31e91ea..ee92e93cf23d 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]; }; @@ -194,6 +195,13 @@ 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; @@ -427,10 +435,17 @@ 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