From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E8B874F55CD; Sat, 5 Sep 2026 18:13:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788632021; cv=none; b=Pq3ukFy7TNvOQAplJywZ184gOkzo0zatiUayPWSIbJRJZW0pwFKgE9L//8w6AzaFNYYJYHehmqeccI99cGvfZ1PUaSpO8lrx+rUthEAAIFrcrMNrEupjFqOXnLVIfDKehYKsluoVtkZS/SnhWievMeT47spGgBpQP0KKpyaom3A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788632021; c=relaxed/simple; bh=FyqiMJOQIIXWVnPhGdNUYdutTzZsipfkHxX+w5Ssz9I=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=k4QgQHrgK3wKojUY9rHv5/rh4gv5SYidJQrYQSJcZGHGdzD3aLtORLt63XoY/xfw19DGtCyIPZGweMpVr3+T8CkNZ3Oj5MDCNwLDvJNR09uNGYeGs36iVUWoF4I03faB4P4fda+4FV9xRQNv1qYWfrzDElrwkmRA+nn0QDywTng= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=uSdWuVh8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="uSdWuVh8" Received: by smtp.kernel.org (Postfix) with ESMTPS id C506FC2BD04; Sat, 5 Sep 2026 18:13:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1788632020; bh=FyqiMJOQIIXWVnPhGdNUYdutTzZsipfkHxX+w5Ssz9I=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=uSdWuVh8YUQYcYnxu1PblDEqNbkAb7lg+fhLKxlIMo75+CWTHNwMt9IA6L26QKU0A 8kL95jizt7LOF7PzjgV9/eHrTBw9Mkn0udVWDJzea3WSoLtRGv4md+PSshXbN28a5E +pI2DXK2CNH1GaiXBukUq4oyPB3nNK/iyXbV759MwMehL1Z0BibdV+Hbwz5FACyhfk AFVx9E0OrFA3d1QGslx1U6Kn7TDxTMC5Qb8UScM3SVIH9ian0HCG2yDlp2saYAK3Qv R2lKisy8Oj4801WI6edt/RLeftX/JuYx+c2XIFNLFZIun2WoDfyeIPy5YxtjiKaSVI mVwWgwDgQ+z4A== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id B16FCC79F8B; Sat, 5 Sep 2026 18:13:40 +0000 (UTC) From: Jim Cromie via B4 Relay Date: Sat, 05 Sep 2026 12:13:33 -0600 Subject: [PATCH v8 19/43] dyndbg: refactor param_set_dyndbg_classes and below Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260905-dd-cmap-part2-clean-v8-19-a4cc0674f6fd@gmail.com> References: <20260905-dd-cmap-part2-clean-v8-0-a4cc0674f6fd@gmail.com> In-Reply-To: <20260905-dd-cmap-part2-clean-v8-0-a4cc0674f6fd@gmail.com> To: Jason Baron , Shuah Khan , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Arnd Bergmann , Luis Chamberlain , Petr Pavlu , Daniel Gomez , Sami Tolvanen , Aaron Tomlin , Andrew Morton , Jonathan Corbet , Shuah Khan , Greg Kroah-Hartman , Nathan Chancellor , Nicolas Schier Cc: linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arch@vger.kernel.org, linux-modules@vger.kernel.org, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, Jim Cromie , Louis Chauvet X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1788632017; l=6792; i=jim.cromie@gmail.com; s=20260203; h=from:subject:message-id; bh=3N66fDJtqesR5DTA1YtRVwEjPz+ZNcyqSUGzcXmHXtA=; b=LvdUXEJczLRdKqGYZYwv07ilxAumkTJck7v456YGCTyzLt2VHHAWpYvoy090SEAY7b2MehziL WxdDo+3Ef1JCqJIEK7Wdtas/m3D0dK7bZWRTujAWPjScW7n0mLrAEtl X-Developer-Key: i=jim.cromie@gmail.com; a=ed25519; pk=C6E5ODlPQo7ZBynATXH9wg7K6HxP0pIXyf4s38Qw0XE= X-Endpoint-Received: by B4 Relay for jim.cromie@gmail.com/20260203 with auth_id=958 X-Original-From: Jim Cromie Reply-To: jim.cromie@gmail.com From: Jim Cromie Refactor the callchain below param_set_dyndbg_classes(1) to allow mod-name specific settings. Split (1) into upper/lower fns, adding modname param to lower, and passing NULL in from upper. Below that, add the same param to ddebug_apply_class_bitmap(), and pass it thru to _ddebug_queries(), replacing NULL with the param. This allows the callchain to update the classmap in just one module, vs just all as currently done. While the sysfs param is unlikely to ever update just one module, the callchain will be used for modprobe handling, which should update only that just-probed module. In ddebug_apply_class_bitmap(), also check for actual changes to the bits before announcing them, to declutter logs. Signed-off-by: Jim Cromie Reviewed-by: Louis Chauvet --- v2: move RvB after SoB v8: drop kdoc on static fn, --- lib/dynamic_debug.c | 73 ++++++++++++++++++++++++++++++++++------------------- 1 file changed, 47 insertions(+), 26 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 2f18d2970aa6..82c4d60d931e 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -618,9 +618,10 @@ static int ddebug_exec_queries(char *query, const char *modname) return nfound; } -/* apply a new bitmap to the sys-knob's current bit-state */ +/* apply a new class-param setting */ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, - unsigned long *new_bits, unsigned long *old_bits) + unsigned long *new_bits, unsigned long *old_bits, + const char *query_modname) { #define QUERY_SIZE 128 char query[QUERY_SIZE]; @@ -628,7 +629,9 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, int matches = 0; int bi, ct; - v2pr_info("apply: 0x%lx to: 0x%lx\n", *new_bits, *old_bits); + if (*new_bits != *old_bits) + v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, + *old_bits, query_modname ?: "'*'"); for (bi = 0; bi < map->length; bi++) { if (test_bit(bi, new_bits) == test_bit(bi, old_bits)) @@ -637,12 +640,16 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi], test_bit(bi, new_bits) ? '+' : '-', dcp->flags); - ct = ddebug_exec_queries(query, NULL); + ct = ddebug_exec_queries(query, query_modname); matches += ct; v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, ct, map->class_names[bi], *new_bits); } + if (*new_bits != *old_bits) + v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, + *old_bits, query_modname ?: "'*'"); + return matches; } @@ -651,22 +658,17 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, #define CLASSMAP_BITMASK(width) ((1UL << (width)) - 1) -/** - * param_set_dyndbg_classes - class FOO >control - * @instr: string echo>d to sysfs, input depends on map_type - * @kp: kp->arg has state: bits/lvl, map, map_type - * - * Enable/disable prdbgs by their class, as given in the arguments to - * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative - * levels by bitpos. - * - * Returns: 0 or <0 if error. +/* + * param-setter helper to validate numeric input, clamp its value by + * the classmap type and size, and apply the bits. */ -int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) +static int param_set_dyndbg_module_classes(const char *instr, + const struct kernel_param *kp, + const char *mod_name) { const struct ddebug_class_param *dcp = kp->arg; const struct ddebug_class_map *map = dcp->map; - unsigned long inrep, new_bits, old_bits; + unsigned long inrep, new_bits, old_bits, old_val; int rc, totct = 0; rc = kstrtoul(instr, 0, &inrep); @@ -686,9 +688,10 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); inrep &= CLASSMAP_BITMASK(map->length); } - v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits); - *dcp->bits = inrep; + old_val = READ_ONCE(*dcp->bits); + v2pr_info("bits:0x%lx > %s.%s\n", inrep, mod_name ?: "*", KP_NAME(kp)); + totct += ddebug_apply_class_bitmap(dcp, &inrep, &old_val, mod_name); + WRITE_ONCE(*dcp->bits, inrep); break; case DD_CLASS_TYPE_LEVEL_NUM: /* input is bitpos, of highest verbosity to be enabled */ @@ -697,11 +700,12 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) KP_NAME(kp), inrep, map->length); inrep = map->length; } - old_bits = CLASSMAP_BITMASK(*dcp->lvl); + old_val = READ_ONCE(*dcp->lvl); + old_bits = CLASSMAP_BITMASK(old_val); new_bits = CLASSMAP_BITMASK(inrep); v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits); - *dcp->lvl = inrep; + totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, mod_name); + WRITE_ONCE(*dcp->lvl, inrep); break; default: pr_warn("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); @@ -710,16 +714,33 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) vpr_info("%s: total matches: %d\n", KP_NAME(kp), totct); return 0; } + +/** + * param_set_dyndbg_classes - classmap-based kernel parameter setter + * @instr: string value to set (numeric bitmask or level) + * @kp: kernel parameter info referencing classmap state + * + * Enable or disable all class'd pr_debug callsites in the classmap, + * independent of the module they're in. + * + * Returns: 0 on success, or a negative error code. + */ +int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) +{ + return param_set_dyndbg_module_classes(instr, kp, NULL); +} EXPORT_SYMBOL(param_set_dyndbg_classes); /** - * param_get_dyndbg_classes - classes reader + * param_get_dyndbg_classes - classmap kparam getter * @buffer: string description of controlled bits -> classes * @kp: kp->arg has state: bits, map * - * Reads last written state, underlying prdbg state may have been - * altered by direct >control. Displays 0x for DISJOINT, 0-N for - * LEVEL Returns: #chars written or <0 on error + * Reads last written state, underlying pr_debug states may have been + * altered by direct >control. Displays 0x for DISJOINT classmap + * types, 0-N for LEVEL types. + * + * Returns: ct of chars written or <0 on error */ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) { -- 2.55.0