From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jim Cromie Date: Wed, 16 Sep 2026 09:33:07 -0600 Subject: [PATCH v10 15/38] dyndbg: refactor param_set_dyndbg_classes and below MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260916-dd-cmap-part2-clean-v10-15-af4cf4767707@gmail.com> References: <20260916-dd-cmap-part2-clean-v10-0-af4cf4767707@gmail.com> In-Reply-To: <20260916-dd-cmap-part2-clean-v10-0-af4cf4767707@gmail.com> To: Jason Baron , Shuah Khan , Andrew Morton , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Arnd Bergmann , Luis Chamberlain , Petr Pavlu , Daniel Gomez , Sami Tolvanen , Aaron Tomlin , Jonathan Corbet , Greg Kroah-Hartman , Nathan Chancellor , Nicolas Schier , Shuah Khan , Randy Dunlap , "Rafael J. Wysocki" , Pavel Machek , Len Brown 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, linux-pm@vger.kernel.org, Jim Cromie , Louis Chauvet X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1789572777; l=6792; i=jim.cromie@gmail.com; s=20260203; h=from:subject:message-id; bh=ZsqxT/rtZBrGWYFLXmA7gUPMn97K+pyumCWiXEAO5/s=; b=m2nJ2CAkef2JrlRelPc4+vZRVUh5mMW1dHt7JS0iN1R8XAjI+KF/8c1wsQt7QocVrjplmeXH1 +frg/KxBcljBQww/3ySRV62nA7C4OqZINUKaiZqTe38Yd+LQf2jzoXT 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 List-Id: B4 Relay Submissions 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 ca8e3cea504c..2b755f18344b 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 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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4B78CC982D0 for ; Wed, 16 Sep 2026 15:33:37 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 18A7F10EC6E; Wed, 16 Sep 2026 15:33:17 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="u+bElh3y"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0CB9910E3D8 for ; Wed, 16 Sep 2026 15:33:02 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 20B724480B; Wed, 16 Sep 2026 15:33:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPS id F30AEC2BD05; Wed, 16 Sep 2026 15:33:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1789572781; bh=9cteVrpVeu+0Wz9UUDswnkAOHWsaXdHrGqz30TkA6eE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=u+bElh3ySiIJ/IysfeiQOpkfdWTDO2WCxsRHCnHWF3UcQoOImG6NX1/FmmeSe4zSG YWRSvFesqJPGDauKKEm7gKx0dQ8WznDUhv0hD+rpLS7j2V41dBW0xw2QzMwS9vhUY0 jIqxHbfy4ccH+nla+Ya5LV2xYWYiSKAggBiZNugenDb8yx4ftlzJq8UCqQQcwmQCjP enH+KG2z/VSrb2t/5CFE4nIN6B4J3LPjcimJtrrY1UT9muGG9nfI6O/WLXALMpLdRL z6vAUmjDlDYGO5nuDae9QTX5GreFOzauvvD2FtcCZfXk1vzhF9StC02K4iWoM1OErk 54+kuZpodF1Fw== 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 DCD5BC982CA; Wed, 16 Sep 2026 15:33:00 +0000 (UTC) From: Jim Cromie via B4 Relay Date: Wed, 16 Sep 2026 09:33:07 -0600 Subject: [PATCH v10 15/38] dyndbg: refactor param_set_dyndbg_classes and below MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260916-dd-cmap-part2-clean-v10-15-af4cf4767707@gmail.com> References: <20260916-dd-cmap-part2-clean-v10-0-af4cf4767707@gmail.com> In-Reply-To: <20260916-dd-cmap-part2-clean-v10-0-af4cf4767707@gmail.com> To: Jason Baron , Shuah Khan , Andrew Morton , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Arnd Bergmann , Luis Chamberlain , Petr Pavlu , Daniel Gomez , Sami Tolvanen , Aaron Tomlin , Jonathan Corbet , Greg Kroah-Hartman , Nathan Chancellor , Nicolas Schier , Shuah Khan , Randy Dunlap , "Rafael J. Wysocki" , Pavel Machek , Len Brown 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, linux-pm@vger.kernel.org, Jim Cromie , Louis Chauvet X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1789572777; l=6792; i=jim.cromie@gmail.com; s=20260203; h=from:subject:message-id; bh=ZsqxT/rtZBrGWYFLXmA7gUPMn97K+pyumCWiXEAO5/s=; b=m2nJ2CAkef2JrlRelPc4+vZRVUh5mMW1dHt7JS0iN1R8XAjI+KF/8c1wsQt7QocVrjplmeXH1 +frg/KxBcljBQww/3ySRV62nA7C4OqZINUKaiZqTe38Yd+LQf2jzoXT 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 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: jim.cromie@gmail.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" 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 ca8e3cea504c..2b755f18344b 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