From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f180.google.com (mail-il1-f180.google.com [209.85.166.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78DCC27E7E3; Sun, 3 Aug 2025 03:59:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754193551; cv=none; b=J22U7Kxe8/nZ0Cp41n4etm/87n5/673lbfTsvyl6JG9ULGSOZviJOR4Wf0oJDjwoRFzjI/BagbDBIvbdHBkOh9lQJBxHLYjdO5Oom3m9xCfcf/e15lFY6ioNPxCs2QOX+MIuc6ZQHS/u8Mw91Mm+nNuFO/Rs6Oa/lPLSlLjLCd0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754193551; c=relaxed/simple; bh=IniLYgUSTHGFusUkLHKW9gzMSDClABs1e5KnGmsM/xA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uzz6Pj9/Sl/hhfH+UbnMJOrt4I2gC4HouLSGDzI+KCb/qSlcXOnb+4oFyGaDuCAoRkZBGK43GDq3HDHg3KY+y24VKU/0QEwnBqwEXTW1ZSdDP2QTE9+DTIm1ZhGsfDyJugQI7xMfMjkX21+DRE9dtqNUL1TdFvcoYa0XRZd3Bis= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=lljzSblB; arc=none smtp.client-ip=209.85.166.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="lljzSblB" Received: by mail-il1-f180.google.com with SMTP id e9e14a558f8ab-3e3ee9c7815so14652365ab.3; Sat, 02 Aug 2025 20:59:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1754193548; x=1754798348; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=iM5cl3dsaaefjUDV3g7+lN+I/LIpHzIWjRiuGDJAMTw=; b=lljzSblBEbnzP4kL3A3cvWTmkGD5Z21LvQTC7TMrbqB2PH5FGnaUpBMNy91QNX47Gh 39R+ovLkZnL9PbQPOe3AKDs15ndn6BM0WBLMvG7/EstQXKDnSaXyYeYeBSGtAx7kvTKw wj8Qu6kLg+zyIrxGDhSxCvJ0BGeQOpcbV3XRL5UDw2r/4orccUwsojP5exJdnH14FU2Y 21rWG2iq4JZ+N08WZj92Gdybo69FKs6acDiphHJqIH81osFQFm4wIusX1LJKkxI99QhV V3Otya2p7jWPc8+idfaZMGMT1UyJ+hzwPra50gSrIE79G319SdRKF0N5yopGq3U5BddB iyeA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754193548; x=1754798348; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iM5cl3dsaaefjUDV3g7+lN+I/LIpHzIWjRiuGDJAMTw=; b=in+zRvsgU6PaAVf8tDgy+rOeUjFl5jNbOVOLY+NgPefqVPQQ/9VwwlQM3SGBp3Vb6c qH7T3cRZvZ+UcSvN07eo5LQuvZrZxoAA7kj8ZHLJ+Ab+1HhnH5+G08rRYoyibDksCtCf YCcABcAzuX4JKYYS8BcKPSO3nK2pRbm+DOLMYuqjaATNq5ADNpw33LNtBWC3zP0aCNxu qlW/waAnx6SIb+76zWWPBJprh1qqCZXsbL+5yDSjn6fupkSOtUxfJzEcfvXy+OrTRtAE HXPc0DA9MKopEGMWY4KJb98YDG6F8nLhs50lXh0UXVn96LK5+OUBhuN1YrZBrTpkKfKk XJbw== X-Forwarded-Encrypted: i=1; AJvYcCUdQic+i3uHkNv+JDj+30FXk6WoKe0fiyuKap2ABqNNsYVEm5JgcOTy1CVY5OTfjnsmZ/oozJKUrau0VkAS@vger.kernel.org, AJvYcCV/xF1fIs4yESHN7lHtY3vNx5lf516bsPJeNSO3ZtJSbqTIuOJ6mhzcs9me3cED7TKzb96lAVDSC9v1@vger.kernel.org X-Gm-Message-State: AOJu0Yxp24rrehZEWc1/TcTzqAwD1nlXRjGgadCcRO+3Re8etNOt90t6 Akjd/4Mb48fzkpXLwah7ZT1KaA/9srRnAZ+BPPE1HPn89IlPhuzyYrTGx4XCmkWeWgM= X-Gm-Gg: ASbGnctcUuwtK+w0623BWRluzitV9BaCu8EaVTs4uTUc49pCC1/Vu2MgyrZkZXZzCb1 xtkBaTqMvflwPjmRQDK25qJGcNj7l6tM5ycnoOy2KDHzX9SMiIAf5j94o6a6ibYdusMNW7gi3l3 tgLYlx7tNrdCCEqxtX5TESvsdJs5G9IleuZu5A6kxccFVwHKafsqEMlM/h07V7l8DyswjaVe0b5 v1HGZLmnBUDy37t/jiGKWQ8AkAJbunX5zbEb6j9riYMR19BCpY6tyFvX/Zu5dglowRF9AmQonMJ L3XrieOGpmN8mn1yEC37uOmkT5ztCluofwhFSI5yg5yCr8AmT6cyzFDmgqcrDTvHSMUa0lw9pKB m5LeWlDubJGHZdbBOVJeSJkwVL/fIZhrpdpXigc7Mm6FpbkWTD09Kz+dCgAseg1vg18BlH9gyGA Waww== X-Google-Smtp-Source: AGHT+IH/unqedwsZLzea1UrYJ2ImjMxVTW1iBpTRcCz5raPVKq3p/sR643AQSxczt1LlvBBkdTbHNg== X-Received: by 2002:a05:6e02:2384:b0:3e3:f67a:7dfb with SMTP id e9e14a558f8ab-3e4160fb74fmr104622345ab.4.1754193548289; Sat, 02 Aug 2025 20:59:08 -0700 (PDT) Received: from frodo.raven-morpho.ts.net (c-67-165-245-5.hsd1.co.comcast.net. [67.165.245.5]) by smtp.googlemail.com with ESMTPSA id 8926c6da1cb9f-50a55df0940sm2268319173.106.2025.08.02.20.59.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 02 Aug 2025 20:59:07 -0700 (PDT) From: Jim Cromie To: linux-kernel@vger.kernel.org, jbaron@akamai.com, gregkh@linuxfoundation.org, ukaszb@chromium.org, louis.chauvet@bootlin.com Cc: dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, daniel.vetter@ffwll.ch, tvrtko.ursulin@linux.intel.com, jani.nikula@intel.com, ville.syrjala@linux.intel.com, seanpaul@chromium.org, robdclark@gmail.com, groeck@google.com, yanivt@google.com, bleung@google.com, quic_saipraka@quicinc.com, will@kernel.org, catalin.marinas@arm.com, quic_psodagud@quicinc.com, maz@kernel.org, arnd@arndb.de, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, mingo@redhat.com, jim.cromie@gmail.com, linux-doc@vger.kernel.org Subject: [PATCH v4 23/58] dyndbg-API: promote DYNAMIC_DEBUG_CLASSMAP_PARAM to API Date: Sat, 2 Aug 2025 21:57:41 -0600 Message-ID: <20250803035816.603405-24-jim.cromie@gmail.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250803035816.603405-1-jim.cromie@gmail.com> References: <20250803035816.603405-1-jim.cromie@gmail.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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, decls a static long unsigned int 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 clean up and improve comments in test-code, and add MODULE_DESCRIPTIONs. cc: linux-doc@vger.kernel.org Signed-off-by: Jim Cromie --- -v9 - fixup drm-print.h add PARAM_REF forwarding macros with DYNAMIC_DEBUG_CLASSMAP_PARAM_REF in the API, add DRM_ variant --- include/linux/dynamic_debug.h | 38 +++++++++++++++++++++ lib/dynamic_debug.c | 60 ++++++++++++++++++++++----------- lib/test_dynamic_debug.c | 47 ++++++++++---------------- lib/test_dynamic_debug_submod.c | 9 ++++- 4 files changed, 104 insertions(+), 50 deletions(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index 9bcada421e88e..2d959f1f8cd30 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -223,6 +223,44 @@ struct _ddebug_class_param { const struct _ddebug_class_map *map; }; +/** + * 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 unsigned long _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 unsigned long 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) + /* * pr_debug() and friends are globally enabled or modules have selectively * enabled them. diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index d6687623c5a96..f7c81a9140bd2 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -666,6 +666,30 @@ static int ddebug_apply_class_bitmap(const struct _ddebug_class_param *dcp, #define CLASSMAP_BITMASK(width) ((1UL << (width)) - 1) +static void ddebug_class_param_clamp_input(unsigned long *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%lx exceeds mask: 0x%lx, 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:%ld exceeds max:%d, clamping\n", + KP_NAME(kp), *inrep, map->length); + *inrep = map->length; + } + break; + } +} static int param_set_dyndbg_module_classes(const char *instr, const struct kernel_param *kp, const char *mod_name) @@ -684,26 +708,15 @@ static int param_set_dyndbg_module_classes(const char *instr, pr_err("expecting numeric input, not: %s > %s\n", 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%lx exceeds mask: 0x%lx, masking\n", - KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); - inrep &= CLASSMAP_BITMASK(map->length); - } v2pr_info("bits:0x%lx > %s.%s\n", inrep, mod_name ?: "*", KP_NAME(kp)); totct += ddebug_apply_class_bitmap(dcp, &inrep, *dcp->bits, mod_name); *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:%ld exceeds max:%d, clamping\n", - KP_NAME(kp), inrep, map->length); - inrep = map->length; - } old_bits = CLASSMAP_BITMASK(*dcp->lvl); new_bits = CLASSMAP_BITMASK(inrep); v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp)); @@ -1171,15 +1184,24 @@ static const struct proc_ops proc_fops = { static void ddebug_sync_classbits(const struct kernel_param *kp, const char *modname) { const struct _ddebug_class_param *dcp = kp->arg; + unsigned long new_bits; - /* clamp initial bitvec, mask off hi-bits */ - if (*dcp->bits & ~CLASSMAP_BITMASK(dcp->map->length)) { - *dcp->bits &= CLASSMAP_BITMASK(dcp->map->length); - v2pr_info("preset classbits: %lx\n", *dcp->bits); + ddebug_class_param_clamp_input(dcp->bits, kp); + + switch (dcp->map->map_type) { + case DD_CLASS_TYPE_DISJOINT_BITS: + v2pr_info(" %s: classbits: 0x%lx\n", KP_NAME(kp), *dcp->bits); + ddebug_apply_class_bitmap(dcp, dcp->bits, 0UL, modname); + break; + case DD_CLASS_TYPE_LEVEL_NUM: + new_bits = CLASSMAP_BITMASK(*dcp->lvl); + v2pr_info(" %s: lvl:%ld bits:0x%lx\n", KP_NAME(kp), *dcp->lvl, new_bits); + ddebug_apply_class_bitmap(dcp, &new_bits, 0UL, modname); + break; + default: + pr_err("bad map type %d\n", dcp->map->map_type); + return; } - /* force class'd prdbgs (in USEr module) to match (DEFINEr module) class-param */ - ddebug_apply_class_bitmap(dcp, dcp->bits, ~0, modname); - ddebug_apply_class_bitmap(dcp, dcp->bits, 0, modname); } static void ddebug_match_apply_kparam(const struct kernel_param *kp, diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c index 8713537363713..d7975b635f17e 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 @@ -62,24 +63,6 @@ module_param_cb(do_prints, ¶m_ops_do_prints, NULL, 0600); #define CLASSMAP_BITMASK(width, base) (((1UL << (width)) - 1) << (base)) -/* sysfs param wrapper, proto-API */ -#define DYNAMIC_DEBUG_CLASSMAP_PARAM_(_model, _flags, _init) \ - static unsigned long 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. * @@ -110,12 +93,15 @@ enum cat_disjoint_bits { /* numeric verbosity, V2 > V1 related. V0 is > D2_DRMRES */ enum cat_level_num { V0 = 16, V1, V2, V3, V4, V5, V6, V7 }; -/* 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, @@ -134,11 +120,13 @@ DYNAMIC_DEBUG_CLASSMAP_DEFINE(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, V0, "V0", "V1", "V2", "V3", "V4", "V5", "V6", "V7"); /* - * now add the sysfs-params + * 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(disjoint_bits, p); -DYNAMIC_DEBUG_CLASSMAP_PARAM(level_num, p); +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 /* @@ -149,12 +137,10 @@ DYNDBG_CLASSMAP_DEFINE(classid_range_conflict, 0, D2_CORE + 1, "D3_CORE"); #endif #else /* TEST_DYNAMIC_DEBUG_SUBMOD */ - /* - * in submod/drm-drivers, use the classmaps defined in top/parent - * module above. + * the +1 members of a multi-module group refer to the classmap + * DEFINEd (and exported) above. */ - DYNAMIC_DEBUG_CLASSMAP_USE(map_disjoint_bits); DYNAMIC_DEBUG_CLASSMAP_USE(map_level_num); @@ -229,6 +215,7 @@ static void __exit test_dynamic_debug_exit(void) module_init(test_dynamic_debug_init); module_exit(test_dynamic_debug_exit); +MODULE_DESCRIPTION("test/demonstrate dynamic-debug features"); MODULE_AUTHOR("Jim Cromie "); MODULE_DESCRIPTION("Kernel module for testing dynamic_debug"); MODULE_LICENSE("GPL"); diff --git a/lib/test_dynamic_debug_submod.c b/lib/test_dynamic_debug_submod.c index 672aabf40160d..3adf3925fb867 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"); -- 2.50.1