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 4BBA2340DB0; Wed, 9 Sep 2026 00:55:04 +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=1788915304; cv=none; b=u0F7U3ZEKZf87wMo4cW+EXEXv1xfHcSPBTdLnwQFXOxoPR806nwDY6I8oX6bYG4X8uxjoGOUxhnZnUrttZr4BwrSEB3tAkNN4XIX7Uje44g6gxD6wwDYcn5Rg2LDXEXmosR+qjukY7AVmNCgvKk0PJXxm+9pGLDgfAB4D8aQFE4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788915304; c=relaxed/simple; bh=w+sKW8iyI1vilMTUdUB74HoNYuTkrUgtCAUtgOnrsU4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=MIR3t9XfKApovSyanapBKVO+wbXiwQk0tl6IH9yRg/V30HbNJE9X6YoMPu/dnv1Hmi1BHh70z53xD2xPs846p3e42zCCGvPb9/xIvu2Zni+MORRFdio3jy5jVJkYTQPKUrZheILq46mHs2SZ+Xpn09Px4SlwOD12C2jukpCYotc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IN/PIg5a; 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="IN/PIg5a" Received: by smtp.kernel.org (Postfix) with ESMTPS id 2CC8CC2BCFB; Wed, 9 Sep 2026 00:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1788915304; bh=w+sKW8iyI1vilMTUdUB74HoNYuTkrUgtCAUtgOnrsU4=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=IN/PIg5a0+mKuG2J3e4OrgIHOSNOanQQWRDDHb+qcwReuxF/qJCTnSEZiH/6+vdEz 9ywyZfwRwbbPpCvf5mRRv68A/QslYKn/9Uwa8YMSn3r3RaGgMG8TKQmunIVj5hkmPl 36m15gWHsdqCWrqiuQhrQO/HFwI1y5JsPIw5tOShQeS7NC/2iZ/SjGBEDzOUc8zWtg +Xb1P7HBJuJ2OBztdKy+uk96gYxKrWsiQgUUePhYGe88zuZvphayG2FUJpTsbL9TM1 Wwh18rkNVcLYsHAlL7OKkUn0NKONduOPYMSFutIiplRsPGvU78oaqn4obezR6VeaLA PMMFjN507DjcQ== 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 1A231C79F82; Wed, 9 Sep 2026 00:55:04 +0000 (UTC) From: Jim Cromie via B4 Relay Date: Tue, 08 Sep 2026 18:55:25 -0600 Subject: [PATCH v9 29/39] dyndbg-API: promote DYNAMIC_DEBUG_CLASSMAP_PARAM to API Precedence: bulk X-Mailing-List: linux-arch@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: <20260908-dd-cmap-part2-clean-v9-29-3a3f621f4a10@gmail.com> References: <20260908-dd-cmap-part2-clean-v9-0-3a3f621f4a10@gmail.com> In-Reply-To: <20260908-dd-cmap-part2-clean-v9-0-3a3f621f4a10@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=1788915300; l=14309; i=jim.cromie@gmail.com; s=20260203; h=from:subject:message-id; bh=K/OMcKv7cpc1y6pRQuqkNN/CbT7sdOLsb68S6JzHmjM=; b=4b5EYzrhLLkzz7UMapVQ5IhjaqyupaJk/QQGsLUq/u8+VKq94H1vYLOsdhzxNGAgr3KDH6RdI duDxkjEMlh+A128uLzy3v5UT26uWRivFElQ5xUBMBg+JfMYduSvakOd 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 move the DYNAMIC_DEBUG_CLASSMAP_PARAM macro from test-dynamic-debug.c into the header, and refine it, by distinguishing the 2 use cases: 1.DYNAMIC_DEBUG_CLASSMAP_PARAM_REF for DRM, to pass in extern __drm_debug by name. dyndbg keeps bits in it, so drm can still use it as before 2.DYNAMIC_DEBUG_CLASSMAP_PARAM new user (test_dynamic_debug) doesn't need to share state, declares a u32 to store the bitvec. __DYNAMIC_DEBUG_CLASSMAP_PARAM bottom layer - allocate,init a ddebug-class-param, module-param-cb. Modify ddebug_sync_classbits() argtype deref inside the fn, to give access to all kp members. Also add stub macros, clean up and improve comments in test-code, and add MODULE_DESCRIPTIONs. cc: linux-doc@vger.kernel.org Signed-off-by: Jim Cromie Reviewed-by: Louis Chauvet --- v9: . fix 4-argument signature for DYNAMIC_DEBUG_CLASSMAP_PARAM_REF fallback macro stub. . update format specifier from %d to %u for inrep in ddebug_class_param_clamp_input(). . drop duplicate v2pr_info() line in param_set_dyndbg_module_classes(). . drop unused CLASSMAP_BITMASK(width, base) define in test_dynamic_debug.c. --- include/linux/dynamic_debug.h | 40 ++++++++++++ lib/dynamic_debug.c | 75 +++++++++++----------- lib/test_dynamic_debug.c | 55 ++++++---------- lib/test_dynamic_debug_submod.c | 9 ++- .../selftests/dynamic_debug/dyndbg_selftest.sh | 2 +- 5 files changed, 106 insertions(+), 75 deletions(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index b53e7488b7f7..cc203b6c1b56 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -293,6 +293,44 @@ struct ddebug_class_param { .offset = _offset \ } +/** + * DYNAMIC_DEBUG_CLASSMAP_PARAM - control a ddebug-classmap from a sys-param + * @_name: sysfs node name + * @_var: name of the classmap var defining the controlled classes/bits + * @_flags: flags to be toggled, typically just 'p' + * + * Creates a sysfs-param to control the classes defined by the + * exported classmap, with bits 0..N-1 mapped to the classes named. + * This version keeps class-state in a private long int. + */ +#define DYNAMIC_DEBUG_CLASSMAP_PARAM(_name, _var, _flags) \ + static u32 _name##_bvec; \ + __DYNAMIC_DEBUG_CLASSMAP_PARAM(_name, _name##_bvec, _var, _flags) + +/** + * DYNAMIC_DEBUG_CLASSMAP_PARAM_REF - wrap a classmap with a controlling sys-param + * @_name: sysfs node name + * @_bits: name of the module's u32 bit-vector, ex: __drm_debug + * @_var: name of the (exported) classmap var defining the classes/bits + * @_flags: flags to be toggled, typically just 'p' + * + * Creates a sysfs-param to control the classes defined by the + * exported clasmap, with bits 0..N-1 mapped to the classes named. + * This version keeps class-state in user @_bits. This lets drm check + * __drm_debug elsewhere too. + */ +#define DYNAMIC_DEBUG_CLASSMAP_PARAM_REF(_name, _bits, _var, _flags) \ + __DYNAMIC_DEBUG_CLASSMAP_PARAM(_name, _bits, _var, _flags) + +#define __DYNAMIC_DEBUG_CLASSMAP_PARAM(_name, _bits, _var, _flags) \ + static struct ddebug_class_param _name##_##_flags = { \ + .bits = &(_bits), \ + .flags = #_flags, \ + .map = &(_var), \ + }; \ + module_param_cb(_name, ¶m_ops_dyndbg_classes, \ + &_name##_##_flags, 0600) + extern __printf(2, 3) void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); @@ -476,6 +514,8 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, #define DYNAMIC_DEBUG_CLASSMAP_DEFINE(_var, _mapty, _base, ...) #define DYNAMIC_DEBUG_CLASSMAP_USE(_var) #define DYNAMIC_DEBUG_CLASSMAP_USE_(_var, _offset) +#define DYNAMIC_DEBUG_CLASSMAP_PARAM(_name, _var, _flags) +#define DYNAMIC_DEBUG_CLASSMAP_PARAM_REF(_name, _bits, _var, _flags) #define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) #define DYNAMIC_DEBUG_BRANCH(descriptor) false #define DECLARE_DYNDBG_CLASSMAP(...) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 11aca5d0c89e..15aba978d3c4 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -697,9 +697,42 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, #define CLASSMAP_BITMASK(width) ((width) >= 32 ? ~0U : (1U << (width)) - 1) -/* - * param-setter helper to validate numeric input, clamp its value by - * the classmap type and size, and apply the bits. +static void __maybe_unused ddebug_class_param_clamp_input(u32 *inrep, const struct kernel_param *kp) +{ + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + + switch (map->map_type) { + case DD_CLASS_TYPE_DISJOINT_BITS: + /* expect bits. mask and warn if too many */ + if (*inrep & ~CLASSMAP_BITMASK(map->length)) { + pr_warn("%s: input: 0x%x exceeds mask: 0x%x, masking\n", + KP_NAME(kp), *inrep, CLASSMAP_BITMASK(map->length)); + *inrep &= CLASSMAP_BITMASK(map->length); + } + break; + case DD_CLASS_TYPE_LEVEL_NUM: + /* input is bitpos, of highest verbosity to be enabled */ + if (*inrep > map->length) { + pr_warn("%s: level:%u exceeds max:%d, clamping\n", + KP_NAME(kp), *inrep, map->length); + *inrep = map->length; + } + break; + } +} + +/** + * 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 + * @mod_name: module name or null for all modules with the classes + * + * 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. */ static int param_set_dyndbg_module_classes(const char *instr, const struct kernel_param *kp, @@ -718,27 +751,16 @@ static int param_set_dyndbg_module_classes(const char *instr, len, instr, KP_NAME(kp)); return -EINVAL; } + ddebug_class_param_clamp_input(&inrep, kp); switch (map->map_type) { case DD_CLASS_TYPE_DISJOINT_BITS: - /* expect bits. mask and warn if too many */ - if (inrep & ~CLASSMAP_BITMASK(map->length)) { - pr_warn("%s: input: 0x%x exceeds mask: 0x%x, masking\n", - KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); - inrep &= CLASSMAP_BITMASK(map->length); - } old_val = READ_ONCE(*dcp->bits); v2pr_info("bits:0x%x > %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 */ - if (inrep > map->length) { - pr_warn("%s: level:%u exceeds max:%d, clamping\n", - KP_NAME(kp), inrep, map->length); - inrep = map->length; - } old_val = READ_ONCE(*dcp->lvl); old_bits = CLASSMAP_BITMASK(old_val); new_bits = CLASSMAP_BITMASK(inrep); @@ -1236,30 +1258,7 @@ static inline u32 ddebug_class_param_to_bits(const struct ddebug_class_param *dc } } -static void __maybe_unused ddebug_class_param_clamp_input(u32 *inrep, const struct kernel_param *kp) -{ - const struct ddebug_class_param *dcp = kp->arg; - const struct ddebug_class_map *map = dcp->map; - switch (map->map_type) { - case DD_CLASS_TYPE_DISJOINT_BITS: - /* expect bits. mask and warn if too many */ - if (*inrep & ~CLASSMAP_BITMASK(map->length)) { - pr_warn("%s: input: 0x%x exceeds mask: 0x%x, masking\n", - KP_NAME(kp), *inrep, CLASSMAP_BITMASK(map->length)); - *inrep &= CLASSMAP_BITMASK(map->length); - } - break; - case DD_CLASS_TYPE_LEVEL_NUM: - /* input is bitpos, of highest verbosity to be enabled */ - if (*inrep > map->length) { - pr_warn("%s: level:%d exceeds max:%d, clamping\n", - KP_NAME(kp), *inrep, map->length); - *inrep = map->length; - } - break; - } -} /* called for class-users only, parse_one does this for definer modules */ static void ddebug_sync_classbits(const struct kernel_param *kp, const char *modname) diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c index b7f9ed9b2794..368891075175 100644 --- a/lib/test_dynamic_debug.c +++ b/lib/test_dynamic_debug.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Kernel module for testing dynamic_debug + * Kernel module to test/demonstrate dynamic_debug features, + * particularly classmaps and their support for subsystems like DRM. * * Authors: * Jim Cromie @@ -68,33 +69,6 @@ static const struct kernel_param_ops param_ops_do_repeats = { module_param_cb(do_classes, ¶m_ops_do_repeats, do_classes, 0600); module_param_cb(do_bulk, ¶m_ops_do_repeats, do_bulk, 0600); -/* - * Using the CLASSMAP api: - * - classmaps must have corresponding enum - * - enum symbols must match/correlate with class-name strings in the map. - * - base must equal enum's 1st value - * - multiple maps must set their base to share the 0-30 class_id space !! - * (build-bug-on tips welcome) - * Additionally, here: - * - tie together sysname, mapname, bitsname, flagsname - */ -#define DYNAMIC_DEBUG_CLASSMAP_PARAM_(_model, _flags, _init) \ - static u32 bits_##_model = _init; \ - static struct ddebug_class_param _flags##_##_model = { \ - .bits = &bits_##_model, \ - .flags = #_flags, \ - .map = &map_##_model, \ - }; \ - module_param_cb(_flags##_##_model, ¶m_ops_dyndbg_classes, \ - &_flags##_##_model, 0600) -#ifdef DEBUG -#define DYNAMIC_DEBUG_CLASSMAP_PARAM(_model, _flags) \ - DYNAMIC_DEBUG_CLASSMAP_PARAM_(_model, _flags, ~0) -#else -#define DYNAMIC_DEBUG_CLASSMAP_PARAM(_model, _flags) \ - DYNAMIC_DEBUG_CLASSMAP_PARAM_(_model, _flags, 0) -#endif - /* * Demonstrate/test DISJOINT & LEVEL typed classmaps with a sys-param. * @@ -128,12 +102,15 @@ enum cat_level_num { V1 = 16, V2, V3, V4, V5, V6, V7, V8 }; /* test _USE_ w offset */ enum cat_level_offset { Vu1 = V1 + 8, Vu2, Vu3, Vu4, Vu5, Vu6, Vu7, Vu8 }; -/* recapitulate DRM's multi-classmap setup */ +/* + * use/demonstrate multi-module-group classmaps, as for DRM + */ #if !defined(TEST_DYNAMIC_DEBUG_SUBMOD) /* - * In single user, or parent / coordinator (drm.ko) modules, define - * classmaps on the client enums above, and then declares the PARAMS - * ref'g the classmaps. Each is exported. + * For module-groups of 1+, define classmaps with names (stringified + * enum-symbols) copied from above. 1-to-1 mapping is recommended. + * The classmap is exported, so that other modules in the group can + * link to it and control their prdbgs. */ DYNAMIC_DEBUG_CLASSMAP_DEFINE(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, D2_CORE, @@ -151,6 +128,15 @@ DYNAMIC_DEBUG_CLASSMAP_DEFINE(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, DYNAMIC_DEBUG_CLASSMAP_DEFINE(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, V1, "V1", "V2", "V3", "V4", "V5", "V6", "V7"); +/* + * for use-cases that want it, provide a sysfs-param to set the + * classes in the classmap. It is at this interface where the + * "v3>v2" property is applied to DD_CLASS_TYPE_LEVEL_NUM inputs. + */ + +DYNAMIC_DEBUG_CLASSMAP_PARAM(p_disjoint_bits, map_disjoint_bits, p); +DYNAMIC_DEBUG_CLASSMAP_PARAM(p_level_num, map_level_num, p); + #ifdef FORCE_CLASSID_CONFLICT /* * Enable with -Dflag on compile to test overlapping class-id range @@ -159,6 +145,7 @@ DYNAMIC_DEBUG_CLASSMAP_DEFINE(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, DYNAMIC_DEBUG_CLASSMAP_DEFINE(classid_range_conflict, 0, D2_CORE + 1, "D3_CORE"); #endif + #if defined(DD_MACRO_ARGCHECK) /* * Exersize compile-time arg-checks in DYNAMIC_DEBUG_CLASSMAP_DEFINE. @@ -192,8 +179,6 @@ DYNAMIC_DEBUG_CLASSMAP_USE_(fail_offset_big, 100); /* * now add the sysfs-params to both sub/super-mods */ -DYNAMIC_DEBUG_CLASSMAP_PARAM(disjoint_bits, p); -DYNAMIC_DEBUG_CLASSMAP_PARAM(level_num, p); /* stand-in for all pr_debug etc */ #define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n") @@ -286,5 +271,5 @@ module_init(test_dynamic_debug_init); module_exit(test_dynamic_debug_exit); MODULE_AUTHOR("Jim Cromie "); -MODULE_DESCRIPTION("Kernel module for testing dynamic_debug"); +MODULE_DESCRIPTION("test/demonstrate dynamic-debug features"); MODULE_LICENSE("GPL"); diff --git a/lib/test_dynamic_debug_submod.c b/lib/test_dynamic_debug_submod.c index 672aabf40160..3adf3925fb86 100644 --- a/lib/test_dynamic_debug_submod.c +++ b/lib/test_dynamic_debug_submod.c @@ -1,6 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Kernel module for testing dynamic_debug + * Kernel module to test/demonstrate dynamic_debug features, + * particularly classmaps and their support for subsystems, like DRM, + * which defines its drm_debug classmap in drm module, and uses it in + * helpers & drivers. * * Authors: * Jim Cromie @@ -12,3 +15,7 @@ */ #define TEST_DYNAMIC_DEBUG_SUBMOD #include "test_dynamic_debug.c" + +MODULE_DESCRIPTION("test/demonstrate dynamic-debug subsystem support"); +MODULE_AUTHOR("Jim Cromie "); +MODULE_LICENSE("GPL"); diff --git a/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh b/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh index 10dc3f2b3fa8..97588c9b07a7 100755 --- a/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh +++ b/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh @@ -655,7 +655,7 @@ function GOLDEN_RECORDS { #K= 4542e1e5e7eadcbe8f90a9c934635618 FT_basic_queries.7 #K= 3bcbdc30323082d6e961b5f0e269fff7 FT_test_classes.1 #K= 5516e3d13cba7ea4197a7fb6c033887a FT_test_classes.2 -#K= 22213a7bf431c3e0efd3edbfcba69677 FT_test_classes.3 +#K= 20d4545f9753e677e72e3adf52527fd3 FT_test_classes.3 #K= 3a6afd41fadaaf70fad18f8a4632ffec FT_classmap_inheritance.1 #K= 6f1e347f0a7930814d2e54d589439465 FT_classmap_inheritance.2 #K= a6e6aab5a6cb9a792d4296b1200ba409 FT_classmap_inheritance.3 -- 2.55.0