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 321F0C3600B for ; Mon, 24 Mar 2025 15:07:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4250710E3DA; Mon, 24 Mar 2025 15:07:48 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="KbN/jq7t"; dkim-atps=neutral Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) by gabe.freedesktop.org (Postfix) with ESMTPS id D804010E3D7; Mon, 24 Mar 2025 15:07:42 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id AD43D442A7; Mon, 24 Mar 2025 15:07:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1742828859; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=dpiZAF4FJD4CIK+ngcfFSqiNbBlkXEDahsbd8DTB28I=; b=KbN/jq7tZzZk0rciFcOOp3vqi8UgNK82rWLBgvkcJgxe+5UoPnkBbGt5sGeYjPX2wU63Pa OYUv7xvs0MHTE8Yop+18njMxTLZlxopFGHKSiQQBgfb2VaR/657np9Wvm9q/DjVHgc71w0 sXW2K1JFqZe942PVLcNIgbkJPBTdKaz4z3BX2M8TxccvSEea9WHLMcUJMHxinZZ6isUTQU SOFsejgF6mK9Q5DldYNS/ZHoR/0dZydjt1gnLn5iCv42KgLg/qLHpLiBiBPNnGBph894d4 02hylPF+qyW4RhLY9tXTyblrB4wemJ/ALXLJSV0W6W60x+TOnne/JNMwdmhm6g== Message-ID: Date: Mon, 24 Mar 2025 16:07:33 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Louis Chauvet Subject: Re: [PATCH 16/63] dyndbg-API: replace DECLARE_DYNDBG_CLASSMAP To: jim.cromie@gmail.com, linux-kernel@vger.kernel.org, jbaron@akamai.com, gregkh@linuxfoundation.org, ukaszb@chromium.org, intel-gfx-trybot@lists.freedesktop.org, 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 References: <20250125064619.8305-1-jim.cromie@gmail.com> <20250125064619.8305-17-jim.cromie@gmail.com> Content-Language: en-US Autocrypt: addr=louis.chauvet@bootlin.com; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-GND-State: clean X-GND-Score: 0 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdduiedttdelucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecunecujfgurhepkfffgggfhffuvfhfjggtgfesthekredttddvjeenucfhrhhomhepnfhouhhishcuvehhrghuvhgvthcuoehlohhuihhsrdgthhgruhhvvghtsegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeghffhiefgueekleetieehjeefffeiudfgtdehteekvdetjeetvdfhffetteevueenucffohhmrghinhepsghoohhtlhhinhdrtghomhenucfkphepledtrdekledrudeifedruddvjeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpeeltddrkeelrdduieefrdduvdejpdhhvghloheplgduledvrdduieekrddtrddvtdgnpdhmrghilhhfrhhomheplhhouhhishdrtghhrghuvhgvthessghoohhtlhhinhdrtghomhdpnhgspghrtghpthhtohepudegpdhrtghpthhtohepjhhimhdrtghrohhmihgvsehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtohepjhgsrghrohhnsegrkhgrmhgrihdrtghomhdprhgtphhtthhopehgrhgvghhkhheslhhinhhugihfohhunhgurghtihhonhdrohhrghdprhgtphhtthhopehukhgrshiisgestghhrhhomhhiu hhmrdhorhhgpdhrtghpthhtohepihhnthgvlhdqghhfgidqthhrhigsohhtsehlihhsthhsrdhfrhgvvgguvghskhhtohhprdhorhhgpdhrtghpthhtohepughrihdquggvvhgvlheslhhishhtshdrfhhrvggvuggvshhkthhophdrohhrghdprhgtphhtthhopegrmhguqdhgfhigsehlihhsthhsrdhfrhgvvgguvghskhhtohhprdhorhhg X-GND-Sasl: louis.chauvet@bootlin.com X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Le 16/03/2025 à 20:46, jim.cromie@gmail.com a écrit : > hi Louis, > > On Tue, Feb 25, 2025 at 7:16 AM Louis Chauvet wrote: >> >> >> >> Le 25/01/2025 à 07:45, Jim Cromie a écrit : >>> DECLARE_DYNDBG_CLASSMAP() has a design error; its usage fails a basic >>> K&R rule: "define once, refer many times". >>> >>> It is used across DRM core & drivers, each use re-defines the classmap >>> understood by that module; and all must match for the modules to >>> respond together when DRM.debug categories are enabled. This is >>> brittle; a maintenance foot-gun. >>> >>> Further, its culpable in the CONFIG_DRM_USE_DYNAMIC_DEBUG=Y >>> regression; its use in both core & drivers obfuscates the 2 roles. >>> So 1st drm.ko loads, and dyndbg initializes its DRM.debug callsites, >>> then a drm-driver loads, but too late - it missed the DRM.debug >>> enablement. >>> >>> So replace it with 2 macros: >>> DYNDBG_CLASSMAP_DEFINE - invoked once from core - drm.ko >>> DYNDBG_CLASSMAP_USE - from all drm drivers and helpers. >>> >>> DYNDBG_CLASSMAP_DEFINE: it just modifies DECLARE_DYNDBG_CLASSMAP, >>> dropping drop the static qualifier, and exports it instead. >>> >>> DYNDBG_CLASSMAP_USE: then refers to the exported var by name: >>> used from drivers, helper-mods >>> lets us drop the repetitive "classname" declarations >>> fixes 2nd-defn problem >>> creates a ddebug_class_user record in new __dyndbg_class_users section >>> this allows ddebug_add_module(etal) to handle users differently. >>> >>> DECLARE_DYNDBG_CLASSMAP is preserved temporarily, to decouple DRM >>> adaptation work and avoid compile-errs before its done. IOW, DRM gets >>> fixed when they commit the adopt-new-api patches, and remove the >>> BROKEN marking. >>> >>> The DEFINE,USE distinction, and the separate classmap-use record, >>> allows dyndbg to initialize the driver's & helper's DRM.debug >>> callsites separately after each is modprobed. >>> >>> Basically, the classmap init-scan is repeated for classmap-users. >>> >>> To review, dyndbg's existing __dyndbg_classes[] section does: >>> >>> . catalogs the classmaps defined by a module (or builtin modules) >>> . tells dyndbg the module has class'd prdbgs, allowing >control >>> . DYNDBG_CLASSMAP_DEFINE creates classmaps in this section. >>> >>> This patch adds __dyndbg_class_users[] section: >>> >>> . catalogs uses/references to the classmap definitions. >>> . authorizes dyndbg to >control those class'd prdbgs in ref'g module. >>> . DYNDBG_CLASSMAP_USE() creates classmap-user records in this new section. >>> >>> Now ddebug_add_module(etal) can handle classmap-uses similar to (and >>> after) classmaps; when a dependent module is loaded, if it has >>> classmap-uses (to a classmap-def in another module), that module's >>> kernel params are scanned to find if it has a kparam that is wired to >>> dyndbg's param-ops, and whose classmap is the one being ref'd. >>> >>> To support this, theres a few data/header changes: >>> >>> new struct ddebug_class_user >>> contains: user-module-name, &classmap-defn >>> it records drm-driver's use of a classmap in the section, allowing lookup >>> >>> struct ddebug_info gets 2 new fields for the new sections: >>> class_users, num_class_users. >>> set by dynamic_debug_init() for builtins. >>> or by kernel/module/main:load_info() for loadable modules. >>> >>> vmlinux.lds.h: new BOUNDED_SECTION for __dyndbg_class_users >>> >>> dynamic_debug.c has 2 changes in ddebug_add_module(), ddebug_change(): >>> >>> ddebug_add_module() already calls ddebug_attach_module_classes() >>> to handle classmaps DEFINEd by a module, now it also calls >>> ddebug_attach_user_module_classes() to handle USEd classmaps. To >>> avoid this work when possible, 1st scan the module's descriptors and >>> count the number of class'd pr_debugs. >>> >>> ddebug_attach_user_module_classes() scans the module's class_users >>> section, follows the refs to the parent's classmap, and calls >>> ddebug_apply_params() on each. It also avoids work by checking the >>> module's class-ct. >>> >>> ddebug_apply_params(new fn): >>> >>> It scans module's/builtin kernel-params, calls ddebug_match_apply_kparam >>> for each to find any params/sysfs-nodes which may be wired to a classmap. >>> >>> ddebug_match_apply_kparam(new fn): >>> >>> 1st, it tests the kernel-param.ops is dyndbg's; this guarantees that >>> the attached arg is a struct ddebug_class_param, which has a ref to >>> the param's state, and to the classmap defining the param's handling. >>> >>> 2nd, it requires that the classmap ref'd by the kparam is the one >>> we're called for; modules can use many separate classmaps (as >>> test_dynamic_debug does). >>> >>> Then apply the "parent" kparam's setting to the dependent module, >>> using ddebug_apply_class_bitmap(). >>> >>> ddebug_change(and callees) also gets adjustments: >>> >>> ddebug_find_valid_class(): This does a search over the module's >>> classmaps, looking for the class FOO echo'd to >control. So now it >>> searches over __dyndbg_class_users[] after __dyndbg_classes[]. >>> >>> ddebug_class_name(): return class-names for defined AND used classes. >>> >>> test_dynamic_debug.c, test_dynamic_debug_submod.c: >>> >>> This demonstrates the 2 types of classmaps & sysfs-params, following >>> the 4-part recipe: >>> >>> 1. define an enum for the classmap: DRM.debug has DRM_UT_{CORE,KMS,...} >>> multiple classes must share 0-62 classid space. >>> 2. DYNDBG_CLASSMAP_DEFINE(.. DRM_UT_{CORE,KMS,...}) >>> 3. DYNDBG_CLASSMAP_PARAM* (classmap) >>> 4. DYNDBG_CLASSMAP_USE() >>> by _submod only, skipping 2,3 >>> >>> Move all the enum declarations together, to better explain how they >>> share the 0..62 class-id space available to a module (non-overlapping >>> subranges). >>> >>> reorg macros 2,3 by name. This gives a tabular format, making it easy >>> to see the pattern of repetition, and the points of change. >>> >>> And extend the test to replicate the 2-module (parent & dependent) >>> scenario which caused the CONFIG_DRM_USE_DYNAMIC_DEBUG=y regression >>> seen in drm & drivers. >>> >>> The _submod.c is a 2-line file: #define _SUBMOD, #include parent. >>> >>> This gives identical complements of prdbgs in parent & _submod, and >>> thus identical print behavior when all of: >control, >params, and >>> parent->_submod propagation are working correctly. >>> >>> It also puts all the parent/_submod declarations together in the same >>> source, with the new ifdef _SUBMOD block invoking DYNDBG_CLASSMAP_USE >>> for the 2 test-interfaces. I think this is clearer. >>> >>> These 2 modules are both tristate, allowing 3 super/sub combos: Y/Y, >>> Y/M, M/M (not N/N). Y/Y testing exposed a missing __align(8) in the >>> _METADATA macro, which M/M didn't see because the module-loader memory >>> placement constrains it instead. >>> >>> NB: this patch ignores a checkpatch do-while warning which is fixed by >>> a preceding commit, which would be wrong for declarative macros like >>> module_param_named() etc. >>> >>> Fixes: aad0214f3026 ("dyndbg: add DECLARE_DYNDBG_CLASSMAP macro") >>> Signed-off-by: Jim Cromie >>> --- >>> v9 - commit-msg tweaks >>> DRM:CHECK warnings on macros: add parens >>> extern DEFINEd _var, static classnames >>> change ddebug_class_user.user_mod_name to .mod_name >>> simplify ddebug_find_valid_class >>> improve vpr_cm_info msg format >>> wrap (base) in macro body >>> move __DYNDBG_CLASSMAP_CHECK above kdoc for DYNDBG_CLASSMAP_DEFINE >>> >>> v8 - split drm parts to separate commits. >>> preserve DECLARE_DYNDBG_CLASSMAP to decouple DRM, no flag day. >>> fixup block comment >>> >>> v7 - previous submission-blocking bug: >>> >>> missing __align(8) in DYNAMIC_DEBUG_DECLARE_METADATA on >>> ddebug_class_user caused corrupt records, but only for builtin >>> modules; module loader code probably pinned allocations to the right >>> alignment naturally, hiding the bug for typical builds. >>> >>> v6- get rid of WARN_ON_ONCE >>> v?- fix _var expanded 2x in macro >>> >>> dyndbg: >>> >>> This fn formerly returned the map which contained the class (thus >>> validating it), and as a side-effect set the class-id in an outvar. >>> >>> But the caller didn't use the map (after checking its not null), only >>> the valid class-id. So simplify the fn to return the class-id of the >>> validated classname, or -ENOENT when the queried classname is not >>> found. >>> >>> Convey more useful info in the debug-msg: print class-names[0,last], >>> and [base,+len] instead of the class-type printout, which is currently >>> always "type:DISJOINT_BITS". And drop ddebug_classmap_typenames, >>> which is now unused. >>> >>> [root@v6 b0-dd]# modprobe test_dynamic_debug_submod >>> [ 18.864962] dyndbg: loaded classmap: test_dynamic_debug [16..24] V0..V7 >>> [ 18.865046] dyndbg: found kp:p_level_num =0x0 >>> [ 18.865048] dyndbg: mapped to: test_dynamic_debug [16..24] V0..V7 >>> [ 18.865164] dyndbg: p_level_num: lvl:0 bits:0x0 >>> [ 18.865217] dyndbg: loaded classmap: test_dynamic_debug [0..10] D2_CORE..D2_DRMRES >>> [ 18.865297] dyndbg: found kp:p_disjoint_bits =0x0 >>> [ 18.865298] dyndbg: mapped to: test_dynamic_debug [0..10] D2_CORE..D2_DRMRES >>> [ 18.865424] dyndbg: p_disjoint_bits: classbits: 0x0 >>> [ 18.865472] dyndbg: module:test_dynamic_debug attached 2 classmaps >>> [ 18.865533] dyndbg: 23 debug prints in module test_dynamic_debug >>> [ 18.866558] dyndbg: loaded classmap: test_dynamic_debug_submod [16..24] V0..V7 >>> [ 18.866698] dyndbg: found kp:p_level_num =0x0 >>> [ 18.866699] dyndbg: mapped to: test_dynamic_debug_submod [16..24] V0..V7 >>> [ 18.866865] dyndbg: p_level_num: lvl:0 bits:0x0 >>> [ 18.866926] dyndbg: loaded classmap: test_dynamic_debug_submod [0..10] D2_CORE..D2_DRMRES >>> [ 18.867026] dyndbg: found kp:p_disjoint_bits =0x0 >>> [ 18.867027] dyndbg: mapped to: test_dynamic_debug_submod [0..10] D2_CORE..D2_DRMRES >>> [ 18.867193] dyndbg: p_disjoint_bits: classbits: 0x0 >>> [ 18.867255] dyndbg: module:test_dynamic_debug_submod attached 2 classmap uses >>> [ 18.867351] dyndbg: 23 debug prints in module test_dynamic_debug_submod >>> --- >>> MAINTAINERS | 2 +- >>> include/asm-generic/vmlinux.lds.h | 1 + >>> include/linux/dynamic_debug.h | 83 ++++++++++-- >>> kernel/module/main.c | 3 + >>> lib/Kconfig.debug | 24 +++- >>> lib/Makefile | 3 + >>> lib/dynamic_debug.c | 203 ++++++++++++++++++++++++------ >>> lib/test_dynamic_debug.c | 111 +++++++++++----- >>> lib/test_dynamic_debug_submod.c | 10 ++ >> >> Hi Jim, >> >> While reading the files test_dynamic_debug*, I was wondering, they are >> more samples than tests. Does it make sense to move them in samples/? >> There is no need to do it in this series. >> >>> 9 files changed, 355 insertions(+), 85 deletions(-) >>> create mode 100644 lib/test_dynamic_debug_submod.c >>> >>> diff --git a/MAINTAINERS b/MAINTAINERS >>> index 0fa7c5728f1e..38afccb3b71e 100644 >>> --- a/MAINTAINERS >>> +++ b/MAINTAINERS >>> @@ -8041,7 +8041,7 @@ M: Jim Cromie >>> S: Maintained >>> F: include/linux/dynamic_debug.h >>> F: lib/dynamic_debug.c >>> -F: lib/test_dynamic_debug.c >>> +F: lib/test_dynamic_debug*.c >>> >>> DYNAMIC INTERRUPT MODERATION >>> M: Tal Gilboa >>> diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h >>> index 54504013c749..eb93fd09832b 100644 >>> --- a/include/asm-generic/vmlinux.lds.h >>> +++ b/include/asm-generic/vmlinux.lds.h >>> @@ -366,6 +366,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) >>> /* implement dynamic printk debug */ \ >>> . = ALIGN(8); \ >>> BOUNDED_SECTION_BY(__dyndbg_classes, ___dyndbg_classes) \ >>> + BOUNDED_SECTION_BY(__dyndbg_class_users, ___dyndbg_class_users) \ >>> BOUNDED_SECTION_BY(__dyndbg, ___dyndbg) \ >>> CODETAG_SECTIONS() \ >>> LIKELY_PROFILE() \ >>> diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h >>> index c8102e89beb2..dc610a12b91c 100644 >>> --- a/include/linux/dynamic_debug.h >>> +++ b/include/linux/dynamic_debug.h >>> @@ -71,9 +71,28 @@ enum ddebug_class_map_type { >>> */ >>> }; >>> >>> +/* > > BTW, Im gonna refine this ... > >>> + * dyndbg-classmaps are devised to support DRM.debug directly: >>> + * 10 enum-vals: DRM_UT_* define the categories >>> + * ~23 categorized *_dbg() macros, each passing a DRM_UT_* val as 1st arg >>> + * 2 macros below them: drm_dev_dbg, __drm_dbg >>> + * ~5000 calls to the categorized macros, across all of drivers/gpu/drm/ >>> + * >>> + * When CONFIG_DRM_USE_DYNAMIC_DEBUG=y, the 2 low macros are redefined >>> + * to invoke _dynamic_func_call_cls(). This compiles the category >>> + * into each callsite's class_id field, where dyndbg can select on it >>> + * and alter a callsite's patch-state, avoiding repeated __drm_debug >>> + * checks. >>> + * >>> + * To make the callsites manageable from the >control file, authors >>> + * provide a "classmap" of names to class_ids in use by the module(s), >>> + * usually by stringifying the enum-vals. Modules with multiple >>> + * classmaps must arrange to share the 0..62 class_id space. >>> + */ >>> + >>> struct ddebug_class_map { >>> - struct module *mod; >>> - const char *mod_name; /* needed for builtins */ >>> + const struct module *mod; /* NULL for builtins */ >>> + const char *mod_name; >> >> Is this change belongs to this patch? If not can you move this in a >> "cleanup" patch? > > It belongs, insofar as the mod field is actually NULL checked to determine > builtin vs modular, mod_name is backup. > Also its more specific than "needed for builtins" > > But, grumble, ya, the above was an existing test, not a new one. > OTOH - I guess Ive just written the cleanup commit msg :-) > >> >>> const char **class_names; >>> const int length; >>> const int base; /* index of 1st .class_id, allows split/shared space */ >>> @@ -81,11 +100,34 @@ struct ddebug_class_map { >>> }; >>> >>> /** >>> - * DECLARE_DYNDBG_CLASSMAP - declare classnames known by a module >>> - * @_var: a struct ddebug_class_map, passed to module_param_cb >>> - * @_type: enum class_map_type, chooses bits/verbose, numeric/symbolic >>> - * @_base: offset of 1st class-name. splits .class_id space >>> - * @classes: class-names used to control class'd prdbgs >>> + * DYNDBG_CLASSMAP_DEFINE - define debug classes used by a module. >>> + * @_var: name of the classmap, exported for other modules coordinated use. >>> + * @_mapty: enum ddebug_class_map_type: 0:DISJOINT - independent, 1:LEVEL - v2>v1> + * @_base: reserve N classids starting at _base, to split 0..62 >> classid space >>> + * @classes: names of the N classes. >>> + * >>> + * This tells dyndbg what class_ids the module is using: _base..+N, by >>> + * mapping names onto them. This qualifies "class NAME" >controls on >>> + * the defining module, ignoring unknown names. >>> + */ >>> +#define DYNDBG_CLASSMAP_DEFINE(_var, _mapty, _base, ...) \ >>> + static const char *_var##_classnames[] = { __VA_ARGS__ }; \ >>> + extern struct ddebug_class_map _var; \ >>> + struct ddebug_class_map __aligned(8) __used \ >>> + __section("__dyndbg_classes") _var = { \ >>> + .mod = THIS_MODULE, \ >>> + .mod_name = KBUILD_MODNAME, \ >>> + .base = (_base), \ >>> + .map_type = (_mapty), \ >>> + .length = ARRAY_SIZE(_var##_classnames), \ >>> + .class_names = _var##_classnames, \ >>> + }; \ >>> + EXPORT_SYMBOL(_var) >>> + >>> +/* >>> + * XXX: keep this until DRM adapts to use the DEFINE/USE api, it >>> + * differs from DYNDBG_CLASSMAP_DEFINE by the static replacing the >>> + * extern/EXPORT on the struct init. >>> */ >>> #define DECLARE_DYNDBG_CLASSMAP(_var, _maptype, _base, ...) \ >>> static const char *_var##_classnames[] = { __VA_ARGS__ }; \ >>> @@ -99,12 +141,37 @@ struct ddebug_class_map { >>> .class_names = _var##_classnames, \ >>> } >>> >>> +struct ddebug_class_user { >>> + char *mod_name; >>> + struct ddebug_class_map *map; >>> +}; >>> + >>> +/** >>> + * DYNDBG_CLASSMAP_USE - refer to a classmap, DEFINEd elsewhere. >>> + * @_var: name of the exported classmap var >>> + * >>> + * This tells dyndbg that the module has prdbgs with classids defined >>> + * in the named classmap. This qualifies "class NAME" >controls on >>> + * the user module, ignoring unknown names. >>> + */ >>> +#define DYNDBG_CLASSMAP_USE(_var) \ >>> + DYNDBG_CLASSMAP_USE_(_var, __UNIQUE_ID(ddebug_class_user)) >>> +#define DYNDBG_CLASSMAP_USE_(_var, _uname) \ >>> + extern struct ddebug_class_map _var; \ >>> + static struct ddebug_class_user __aligned(8) __used \ >>> + __section("__dyndbg_class_users") _uname = { \ >>> + .mod_name = KBUILD_MODNAME, \ >>> + .map = &(_var), \ >>> + } >>> + >> >> I'm not sure I understand properly how __section works, but can we use >> multiple DYNDBG_CLASSMAP_USE in one module? Can we also use >> DYNDBG_CLASSMAP_DEFINE while also importing an other classmap >> DYNDBG_CLASSMAP_USE? >> > > Yes, its supposed to work that way. > > I havent tested that specific scenario (yet), but > a _USEr module, like test-dynamic-debug-submod, > could also _DEFINE its own, as long as it honors > the class-id mapping it is using and therefore sharing. > The on-modprobe conflict check should catch this condition. > > And __section (ISTM) accumulates entries, typically static struct var > initializations. > AFAICT, scanning the sections is how these { scoped statics } are > often reachable. > > For example, dd's _METADATA_ builds a { static _ddebug } for every pr_debug. > They all go into the __dyndbg section (renamed with _descriptors suffix soon), > in the order their respective definer objects are linked. > > include/asm-generic/vmlinux.lds.h then places the __dyndbg_* sections > into DATA, along with lots of other freight, for the various > mechanisms they serve. > > > > >> If not, does it make sense to allow it (for example MFD devices can >> touch multiple subsystems)? > > We have another use case ! > Do you know your way around that case ? > No, I don't have other use cases, I was just thinking about possible scenarios of the "include multiple classmap". So, happy to konw it is not an issue with the section, but do I understand properly the code (completly hypotetical example): if drm.ko defines classes 0..10 and spi.ko defines classes 0..4, it means driver.ko can't use both classmap? (I don't have such use-case, and maybe this use-case does not exists!) The only solution I see is to add more stuff in the _ddebug structure (for example a "classmap identifier"). But for now, the current user will be DRM, so we don't really need to fix this issue right now. I just found a possible user for dyndbg classes [1], it seems to implement something similar. [1]:https://elixir.bootlin.com/linux/v6.13.7/source/drivers/block/drbd/drbd_polymorph_printk.h > Note that DEFINEr & USEr calls set up linkage dependencies, > As long as these are consistent with other module deps, > it should work. > > >> >>> /* encapsulate linker provided built-in (or module) dyndbg data */ >>> struct _ddebug_info { >>> struct _ddebug *descs; >>> struct ddebug_class_map *classes; >>> + struct ddebug_class_user *class_users; >>> unsigned int num_descs; >>> unsigned int num_classes; >>> + unsigned int num_class_users; >>> }; >>> >>> struct ddebug_class_param { >>> @@ -205,7 +272,7 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, >>> * (|_no_desc): former gets callsite descriptor as 1st arg (for prdbgs) >>> */ >>> #define __dynamic_func_call_cls(id, cls, fmt, func, ...) do { \ >>> - DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \ >>> + DEFINE_DYNAMIC_DEBUG_METADATA_CLS((id), cls, fmt); \ >> >> Can you move this in a "cleanup" patch? >> >>> if (DYNAMIC_DEBUG_BRANCH(id)) \ >>> func(&id, ##__VA_ARGS__); \ >>> } while (0) >>> diff --git a/kernel/module/main.c b/kernel/module/main.c >>> index 5399c182b3cb..c394a0c6e8c6 100644 >>> --- a/kernel/module/main.c >>> +++ b/kernel/module/main.c >>> @@ -2546,6 +2546,9 @@ static int find_module_sections(struct module *mod, struct load_info *info) >>> mod->dyndbg_info.classes = section_objs(info, "__dyndbg_classes", >>> sizeof(*mod->dyndbg_info.classes), >>> &mod->dyndbg_info.num_classes); >>> + mod->dyndbg_info.class_users = section_objs(info, "__dyndbg_class_users", >>> + sizeof(*mod->dyndbg_info.class_users), >>> + &mod->dyndbg_info.num_class_users); >>> #endif >>> >>> return 0; >>> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug >>> index f3d723705879..933f69ef87f8 100644 >>> --- a/lib/Kconfig.debug >>> +++ b/lib/Kconfig.debug >>> @@ -2884,12 +2884,26 @@ config TEST_STATIC_KEYS >>> If unsure, say N. >>> >>> config TEST_DYNAMIC_DEBUG >>> - tristate "Test DYNAMIC_DEBUG" >>> - depends on DYNAMIC_DEBUG >>> + tristate "Build test-dynamic-debug module" >>> + depends on DYNAMIC_DEBUG || DYNAMIC_DEBUG_CORE >>> help >>> - This module registers a tracer callback to count enabled >>> - pr_debugs in a 'do_debugging' function, then alters their >>> - enablements, calls the function, and compares counts. >>> + This module exercises/demonstrates dyndbg's classmap API, by >>> + creating 2 classes: a DISJOINT classmap (supporting DRM.debug) >>> + and a LEVELS/VERBOSE classmap (like verbose2 > verbose1). >>> + >>> + If unsure, say N. >>> + >>> +config TEST_DYNAMIC_DEBUG_SUBMOD >>> + tristate "Build test-dynamic-debug submodule" >>> + default m >>> + depends on DYNAMIC_DEBUG || DYNAMIC_DEBUG_CORE >>> + depends on TEST_DYNAMIC_DEBUG >>> + help >>> + This sub-module uses a classmap defined and exported by the >>> + parent module, recapitulating drm & driver's shared use of >>> + drm.debug to control enabled debug-categories. >>> + It is tristate, independent of parent, to allow testing all >>> + proper combinations of parent=y/m submod=y/m. >>> >>> If unsure, say N. >>> >>> diff --git a/lib/Makefile b/lib/Makefile >>> index a8155c972f02..7f66fc1c163d 100644 >>> --- a/lib/Makefile >>> +++ b/lib/Makefile >>> @@ -84,6 +84,7 @@ obj-$(CONFIG_TEST_SORT) += test_sort.o >>> obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o >>> obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o >>> obj-$(CONFIG_TEST_DYNAMIC_DEBUG) += test_dynamic_debug.o >>> +obj-$(CONFIG_TEST_DYNAMIC_DEBUG_SUBMOD) += test_dynamic_debug_submod.o >>> obj-$(CONFIG_TEST_PRINTF) += test_printf.o >>> obj-$(CONFIG_TEST_SCANF) += test_scanf.o >>> >>> @@ -228,6 +229,8 @@ obj-$(CONFIG_ARCH_NEED_CMPXCHG_1_EMU) += cmpxchg-emu.o >>> obj-$(CONFIG_DYNAMIC_DEBUG_CORE) += dynamic_debug.o >>> #ensure exported functions have prototypes >>> CFLAGS_dynamic_debug.o := -DDYNAMIC_DEBUG_MODULE >>> +CFLAGS_test_dynamic_debug.o := -DDYNAMIC_DEBUG_MODULE >>> +CFLAGS_test_dynamic_debug_submod.o := -DDYNAMIC_DEBUG_MODULE >>> >>> obj-$(CONFIG_SYMBOLIC_ERRNAME) += errname.o >>> >>> diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c >>> index 094d6e62a9d1..6bca0c6727d4 100644 >>> --- a/lib/dynamic_debug.c >>> +++ b/lib/dynamic_debug.c >>> @@ -43,13 +43,16 @@ extern struct _ddebug __start___dyndbg[]; >>> extern struct _ddebug __stop___dyndbg[]; >>> extern struct ddebug_class_map __start___dyndbg_classes[]; >>> extern struct ddebug_class_map __stop___dyndbg_classes[]; >>> +extern struct ddebug_class_user __start___dyndbg_class_users[]; >>> +extern struct ddebug_class_user __stop___dyndbg_class_users[]; >>> >>> struct ddebug_table { >>> struct list_head link; >>> const char *mod_name; >>> struct _ddebug *ddebugs; >>> struct ddebug_class_map *classes; >>> - unsigned int num_ddebugs, num_classes; >>> + struct ddebug_class_user *class_users; >>> + unsigned int num_ddebugs, num_classes, num_class_users; >>> }; >>> >>> struct ddebug_query { >>> @@ -148,23 +151,35 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg) >>> query->first_lineno, query->last_lineno, query->class_string); >>> } >>> >>> -#define __outvar /* filled by callee */ >>> -static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt, >>> - const char *class_string, >>> - __outvar int *class_id) >>> +#define vpr_dt_info(dt_p, msg_p, ...) ({ \ >>> + struct ddebug_table const *_dt = dt_p; \ >>> + v2pr_info(msg_p " module:%s nd:%d nc:%d nu:%d\n", ##__VA_ARGS__, \ >>> + _dt->mod_name, _dt->num_ddebugs, _dt->num_classes, \ >>> + _dt->num_class_users); \ >>> + }) >>> + >>> +static int ddebug_find_valid_class(struct ddebug_table const *dt, const char *class_string) >>> { >>> struct ddebug_class_map *map; >>> + struct ddebug_class_user *cli; >>> int i, idx; >>> >>> - for (map = dt->classes, i = 0; i < dt->num_classes; i++, map++) { >>> + for (i = 0, map = dt->classes; i < dt->num_classes; i++, map++) { >>> idx = match_string(map->class_names, map->length, class_string); >>> if (idx >= 0) { >>> - *class_id = idx + map->base; >>> - return map; >>> + vpr_dt_info(dt, "good-class: %s.%s ", map->mod_name, class_string); >>> + return idx + map->base; >>> } >>> } >>> - *class_id = -ENOENT; >>> - return NULL; >>> + for (i = 0, cli = dt->class_users; i < dt->num_class_users; i++, cli++) { >>> + idx = match_string(cli->map->class_names, cli->map->length, class_string); >>> + if (idx >= 0) { >>> + vpr_dt_info(dt, "class-ref: %s -> %s.%s ", >>> + cli->mod_name, cli->map->mod_name, class_string); >>> + return idx + cli->map->base; >>> + } >>> + } >>> + return -ENOENT; >>> } >>> >>> /* >>> @@ -173,16 +188,14 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons >>> * callsites, normally the same as number of changes. If verbose, >>> * logs the changes. Takes ddebug_lock. >>> */ >>> -static int ddebug_change(const struct ddebug_query *query, >>> - struct flag_settings *modifiers) >>> +static int ddebug_change(const struct ddebug_query *query, struct flag_settings *modifiers) >>> { >>> int i; >>> struct ddebug_table *dt; >>> unsigned int newflags; >>> unsigned int nfound = 0; >>> struct flagsbuf fbuf, nbuf; >>> - struct ddebug_class_map *map = NULL; >>> - int __outvar valid_class; >>> + int valid_class; >>> >>> /* search for matching ddebugs */ >>> mutex_lock(&ddebug_lock); >>> @@ -194,8 +207,8 @@ static int ddebug_change(const struct ddebug_query *query, >>> continue; >>> >>> if (query->class_string) { >>> - map = ddebug_find_valid_class(dt, query->class_string, &valid_class); >>> - if (!map) >>> + valid_class = ddebug_find_valid_class(dt, query->class_string); >>> + if (valid_class < 0) >>> continue; >>> } else { >>> /* constrain query, do not touch class'd callsites */ >>> @@ -559,7 +572,7 @@ static int ddebug_exec_query(char *query_string, const char *modname) >>> >>> /* handle multiple queries in query string, continue on error, return >>> last error or number of matching callsites. Module name is either >>> - in param (for boot arg) or perhaps in query string. >>> + in the modname arg (for boot args) or perhaps in query string. >>> */ >>> static int ddebug_exec_queries(char *query, const char *modname) >>> { >>> @@ -688,12 +701,12 @@ static int param_set_dyndbg_module_classes(const char *instr, >>> } >>> >>> /** >>> - * param_set_dyndbg_classes - class FOO >control >>> + * param_set_dyndbg_classes - set all classes in a classmap >>> * @instr: string echo>d to sysfs, input depends on map_type >>> - * @kp: kp->arg has state: bits/lvl, map, map_type >>> + * @kp: kp->arg has state: bits/lvl, classmap, map_type >>> * >>> - * Enable/disable prdbgs by their class, as given in the arguments to >>> - * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative >>> + * For all classes in the classmap, enable/disable them per the input >>> + * (depending on map_type). For LEVEL map-types, enforce relative >>> * levels by bitpos. >>> * >>> * Returns: 0 or <0 if error. >>> @@ -1038,12 +1051,17 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) >>> static const char *ddebug_class_name(struct ddebug_table *dt, struct _ddebug *dp) >>> { >>> struct ddebug_class_map *map = dt->classes; >>> + struct ddebug_class_user *cli = dt->class_users; >>> int i; >>> >>> for (i = 0; i < dt->num_classes; i++, map++) >>> if (class_in_range(dp->class_id, map)) >>> return map->class_names[dp->class_id - map->base]; >>> >>> + for (i = 0; i < dt->num_class_users; i++, cli++) >>> + if (class_in_range(dp->class_id, cli->map)) >>> + return cli->map->class_names[dp->class_id - cli->map->base]; >>> + >>> return NULL; >>> } >>> >>> @@ -1124,31 +1142,129 @@ static const struct proc_ops proc_fops = { >>> .proc_write = ddebug_proc_write >>> }; >>> >>> -static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug_info *di) >>> +#define vpr_cm_info(cm_p, msg_fmt, ...) ({ \ >>> + struct ddebug_class_map const *_cm = cm_p; \ >>> + v2pr_info(msg_fmt " %s [%d..%d] %s..%s\n", ##__VA_ARGS__, \ >>> + _cm->mod_name, _cm->base, _cm->base + _cm->length, \ >>> + _cm->class_names[0], _cm->class_names[_cm->length - 1]); \ >>> + }) >>> + >>> +static void ddebug_sync_classbits(const struct kernel_param *kp, const char *modname) >>> +{ >>> + const struct ddebug_class_param *dcp = kp->arg; >>> + >>> + /* 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); >>> + } >>> + /* 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, >>> + const struct ddebug_class_map *map, >>> + const char *modnm) >>> +{ >>> + struct ddebug_class_param *dcp; >>> + >>> + if (kp->ops != ¶m_ops_dyndbg_classes) >>> + return; >>> + >>> + dcp = (struct ddebug_class_param *)kp->arg; >>> + >>> + if (map == dcp->map) { >>> + v2pr_info(" kp:%s.%s =0x%lx", modnm, kp->name, *dcp->bits); >>> + vpr_cm_info(map, " %s mapped to: ", modnm); >>> + ddebug_sync_classbits(kp, modnm); >>> + } >>> +} >>> + >>> +static void ddebug_apply_params(const struct ddebug_class_map *cm, const char *modnm) >>> +{ >>> + const struct kernel_param *kp; >>> +#if IS_ENABLED(CONFIG_MODULES) >>> + int i; >>> + >>> + if (cm->mod) { >>> + vpr_cm_info(cm, "loaded classmap: %s", modnm); >>> + /* ifdef protects the cm->mod->kp deref */ >>> + for (i = 0, kp = cm->mod->kp; i < cm->mod->num_kp; i++, kp++) >>> + ddebug_match_apply_kparam(kp, cm, modnm); >>> + } >>> +#endif >>> + if (!cm->mod) { >>> + vpr_cm_info(cm, "builtin classmap: %s", modnm); >>> + for (kp = __start___param; kp < __stop___param; kp++) >>> + ddebug_match_apply_kparam(kp, cm, modnm); >>> + } >>> +} >>> + >>> +/* >>> + * Find this module's classmaps in a sub/whole-range of the builtin/ >>> + * modular classmap vector/section. Save the start and length of the >>> + * subrange at its edges. >>> + */ >>> +static void ddebug_attach_module_classes(struct ddebug_table *dt, >>> + const struct _ddebug_info *di) >>> { >>> struct ddebug_class_map *cm; >>> int i, nc = 0; >>> >>> - /* >>> - * Find this module's classmaps in a subrange/wholerange of >>> - * the builtin/modular classmap vector/section. Save the start >>> - * and length of the subrange at its edges. >>> - */ >>> - for (cm = di->classes, i = 0; i < di->num_classes; i++, cm++) { >>> - >>> + for (i = 0, cm = di->classes; i < di->num_classes; i++, cm++) { >>> if (!strcmp(cm->mod_name, dt->mod_name)) { >>> - if (!nc) { >>> - v2pr_info("start subrange, class[%d]: module:%s base:%d len:%d ty:%d\n", >>> - i, cm->mod_name, cm->base, cm->length, cm->map_type); >>> + vpr_cm_info(cm, "classes[%d]:", i); >>> + if (!nc++) >>> dt->classes = cm; >>> - } >>> - nc++; >>> } >>> } >>> - if (nc) { >>> - dt->num_classes = nc; >>> - vpr_info("module:%s attached %d classes\n", dt->mod_name, nc); >>> + if (!nc) >>> + return; >>> + >>> + vpr_info("module:%s attached %d classes\n", dt->mod_name, nc); >>> + dt->num_classes = nc; >>> + >>> + for (i = 0, cm = dt->classes; i < dt->num_classes; i++, cm++) >>> + ddebug_apply_params(cm, cm->mod_name); >>> +} >>> + >>> +/* >>> + * propagates class-params thru their classmaps to class-users. this >>> + * means a query against the dt/module, which means it must be on the >>> + * list to be seen by ddebug_change. >>> + */ >>> +static void ddebug_attach_user_module_classes(struct ddebug_table *dt, >>> + const struct _ddebug_info *di) >>> +{ >>> + struct ddebug_class_user *cli; >>> + int i, nc = 0; >>> + >>> + /* >>> + * For builtins: scan the array, find start/length of this >>> + * module's refs, save to dt. For loadables, this is the >>> + * whole array. >>> + */ >>> + for (i = 0, cli = di->class_users; i < di->num_class_users; i++, cli++) { >>> + if (WARN_ON_ONCE(!cli || !cli->map || !cli->mod_name)) >>> + continue; >>> + if (!strcmp(cli->mod_name, dt->mod_name)) { >>> + vpr_cm_info(cli->map, "class_ref[%d] %s -> %s", i, >>> + cli->mod_name, cli->map->mod_name); >>> + if (!nc++) >>> + dt->class_users = cli; >>> + } >>> } >>> + if (!nc) >>> + return; >>> + >>> + dt->num_class_users = nc; >>> + >>> + /* now iterate dt */ >>> + for (i = 0, cli = dt->class_users; i < dt->num_class_users; i++, cli++) >>> + ddebug_apply_params(cli->map, cli->mod_name); >>> + >>> + vpr_dt_info(dt, "attach-client-module: "); >>> } >>> >>> /* >>> @@ -1158,6 +1274,8 @@ static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug >>> static int ddebug_add_module(struct _ddebug_info *di, const char *modname) >>> { >>> struct ddebug_table *dt; >>> + struct _ddebug *iter; >>> + int i, class_ct = 0; >>> >>> if (!di->num_descs) >>> return 0; >>> @@ -1181,13 +1299,20 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname) >>> >>> INIT_LIST_HEAD(&dt->link); >>> >>> - if (di->classes && di->num_classes) >>> + for (i = 0, iter = di->descs; i < di->num_descs; i++, iter++) >>> + if (iter->class_id != _DPRINTK_CLASS_DFLT) >>> + class_ct++; >>> + >>> + if (class_ct && di->num_classes) >>> ddebug_attach_module_classes(dt, di); >>> >>> mutex_lock(&ddebug_lock); >>> list_add_tail(&dt->link, &ddebug_tables); >>> mutex_unlock(&ddebug_lock); >>> >>> + if (class_ct && di->num_class_users) >>> + ddebug_attach_user_module_classes(dt, di); >>> + >>> vpr_info("%3u debug prints in module %s\n", di->num_descs, modname); >>> return 0; >>> } >>> @@ -1337,8 +1462,10 @@ static int __init dynamic_debug_init(void) >>> struct _ddebug_info di = { >>> .descs = __start___dyndbg, >>> .classes = __start___dyndbg_classes, >>> + .class_users = __start___dyndbg_class_users, >>> .num_descs = __stop___dyndbg - __start___dyndbg, >>> .num_classes = __stop___dyndbg_classes - __start___dyndbg_classes, >>> + .num_class_users = __stop___dyndbg_class_users - __start___dyndbg_class_users, >>> }; >>> >>> #ifdef CONFIG_MODULES >>> diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c >>> index 74d183ebf3e0..1838f62738c4 100644 >>> --- a/lib/test_dynamic_debug.c >>> +++ b/lib/test_dynamic_debug.c >>> @@ -6,11 +6,15 @@ >>> * Jim Cromie >>> */ >>> >>> -#define pr_fmt(fmt) "test_dd: " fmt >>> +#if defined(TEST_DYNAMIC_DEBUG_SUBMOD) >>> + #define pr_fmt(fmt) "test_dd_submod: " fmt >>> +#else >>> + #define pr_fmt(fmt) "test_dd: " fmt >>> +#endif >>> >>> #include >>> >>> -/* run tests by reading or writing sysfs node: do_prints */ >>> +/* re-gen output by reading or writing sysfs node: do_prints */ >>> >>> static void do_prints(void); /* device under test */ >>> static int param_set_do_prints(const char *instr, const struct kernel_param *kp) >>> @@ -29,24 +33,39 @@ static const struct kernel_param_ops param_ops_do_prints = { >>> }; >>> module_param_cb(do_prints, ¶m_ops_do_prints, NULL, 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 DD_SYS_WRAP(_model, _flags) \ >>> - static unsigned long bits_##_model; \ >>> - static struct ddebug_class_param _flags##_model = { \ >>> +#define CLASSMAP_BITMASK(width, base) (((1UL << (width)) - 1) << (base)) >>> + >>> +/* sysfs param wrapper, proto-API */ >>> +#define DYNDBG_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) >>> + module_param_cb(_flags##_##_model, ¶m_ops_dyndbg_classes, \ >>> + &_flags##_##_model, 0600) >>> +#ifdef DEBUG >>> +#define DYNDBG_CLASSMAP_PARAM(_model, _flags) DYNDBG_CLASSMAP_PARAM_(_model, _flags, ~0) >>> +#else >>> +#define DYNDBG_CLASSMAP_PARAM(_model, _flags) DYNDBG_CLASSMAP_PARAM_(_model, _flags, 0) >>> +#endif >>> + >>> +/* >>> + * Demonstrate/test all 4 class-typed classmaps with a sys-param. >>> + * >>> + * Each is 3 part: client-enum decl, _DEFINE, _PARAM. >>> + * Declare them in blocks to show patterns of use (repetitions and >>> + * changes) within each. >>> + * >>> + * 1st, dyndbg expects a client-provided enum-type as source of >>> + * category/classid truth. DRM has DRM_UT_. >>> + * >>> + * Modules with multiple CLASSMAPS must have enums with distinct >>> + * value-ranges, arranged below with explicit enum_sym = X inits. >>> + * >>> + * Declare all 4 enums now, for different types >>> + */ >>> >>> /* numeric input, independent bits */ >>> enum cat_disjoint_bits { >>> @@ -60,26 +79,51 @@ enum cat_disjoint_bits { >>> D2_LEASE, >>> D2_DP, >>> D2_DRMRES }; >>> -DECLARE_DYNDBG_CLASSMAP(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, 0, >>> - "D2_CORE", >>> - "D2_DRIVER", >>> - "D2_KMS", >>> - "D2_PRIME", >>> - "D2_ATOMIC", >>> - "D2_VBL", >>> - "D2_STATE", >>> - "D2_LEASE", >>> - "D2_DP", >>> - "D2_DRMRES"); >>> -DD_SYS_WRAP(disjoint_bits, p); >>> -DD_SYS_WRAP(disjoint_bits, T); >>> >>> /* numeric verbosity, V2 > V1 related */ >>> enum cat_level_num { V0 = 14, V1, V2, V3, V4, V5, V6, V7 }; >>> -DECLARE_DYNDBG_CLASSMAP(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, 14, >>> - "V0", "V1", "V2", "V3", "V4", "V5", "V6", "V7"); >>> -DD_SYS_WRAP(level_num, p); >>> -DD_SYS_WRAP(level_num, T); >>> + >>> +/* recapitulate DRM's parent(drm.ko) <-- _submod(drivers,helpers) */ >>> +#if !defined(TEST_DYNAMIC_DEBUG_SUBMOD) >> >> It was not clear at first read that the test_dynamic_debug.c code is >> used twice. >> > > Yes, that was a miss. Now in big comment block at the top of both, > right before the pr-fmt mod-name shortening for the logs. > > >> What do you think about creating a third file "common" with >> do_prints/do_levels/... implementations and avoid this #if !defined? >> > > I'd rather not. I think the multi-module usage is sufficiently interconnected > (common enum, parent side, clone side) that all-in-one presentation > helps to communicate this "linkage". > > I hope the new comments clearly elucidate this. PLMK if not. > >>> +/* >>> + * 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. >>> + */ >>> +DYNDBG_CLASSMAP_DEFINE(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, >> >> map_disjoint_bits is defined in both test_dynamic_debug.c and >> test_dynamic_debug_submodule.c, is it normal/required? > > Its the enum : cat_disjoint_bits, that is defined for both. > > the _DEFINE itself is right after the ifdef TEST_MOD_SUBMOD. > > do you think it needs a better MOD_SUBMOD name ? > or an ifndef ? > >> >>> + D2_CORE, >>> + "D2_CORE", >>> + "D2_DRIVER", >>> + "D2_KMS", >>> + "D2_PRIME", >>> + "D2_ATOMIC", >>> + "D2_VBL", >>> + "D2_STATE", >>> + "D2_LEASE", >>> + "D2_DP", >>> + "D2_DRMRES"); >>> + >>> +DYNDBG_CLASSMAP_DEFINE(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, >>> + V0, "V0", "V1", "V2", "V3", "V4", "V5", "V6", "V7"); >>> + >>> +/* >>> + * now add the sysfs-params >>> + */ >>> + >>> +DYNDBG_CLASSMAP_PARAM(disjoint_bits, p); >>> +DYNDBG_CLASSMAP_PARAM(level_num, p); >>> + >>> +#else /* TEST_DYNAMIC_DEBUG_SUBMOD */ >>> + >>> +/* >>> + * in submod/drm-drivers, use the classmaps defined in top/parent >>> + * module above. >>> + */ >>> + >>> +DYNDBG_CLASSMAP_USE(map_disjoint_bits); >>> +DYNDBG_CLASSMAP_USE(map_level_num); >>> + >>> +#endif >>> >>> /* stand-in for all pr_debug etc */ >>> #define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n") >>> @@ -115,6 +159,7 @@ static void do_levels(void) >>> >>> static void do_prints(void) >>> { >>> + pr_debug("do_prints:\n"); >>> do_cats(); >>> do_levels(); >> >> I just observed it, is the ordering of logs garanteed in >> /proc/dynamic_debug/control? >> > > Yes. the fully ordered table/__section is pretty important. > If its not true for descriptors, its probably not true for class-maps > or users either > and the list-iter --> vector-block conversion a few commits ago isnt > solid either. > > its also an explicit assumption under these commits > > 773beabbb8e8 dyndbg: reverse module.callsite walk in cat control > 2ad556f70043 dyndbg: reverse module walk in cat control > > All in all, I think something would have broken by now. > > >> When I run this test, I have this order: >> >> do_cats =_ "doing categories\n" >> [...] >> do_levels =_ "doing levels\n" >> [...] >> do_prints =_ "do_prints:\n" >> test_dynamic_debug_init =_ "init start\n" >> test_dynamic_debug_init =_ "init done\n" >> test_dynamic_debug_exit =_ "exited\n" >> >> Which is clearly not the code execution order. > > Youre correct. > the control file reflects compile link order. > > Im pretty sure the appearance of init 1st in control derives from init/builtin.a > being built 1st and/or linked 1st. > >> >>> } >>> diff --git a/lib/test_dynamic_debug_submod.c b/lib/test_dynamic_debug_submod.c >>> new file mode 100644 >>> index 000000000000..9a893402ce1a >>> --- /dev/null >>> +++ b/lib/test_dynamic_debug_submod.c >>> @@ -0,0 +1,10 @@ >>> +// SPDX-License-Identifier: GPL-2.0 >>> +/* >>> + * Kernel module for testing dynamic_debug >>> + * >>> + * Authors: >>> + * Jim Cromie >>> + */ >>> + >>> +#define TEST_DYNAMIC_DEBUG_SUBMOD >>> +#include "test_dynamic_debug.c" >> >> -- >> Louis Chauvet, Bootlin >> Embedded Linux and Kernel engineering >> https://bootlin.com >> > > thanks again Lous, > Jim -- Louis Chauvet, Bootlin Embedded Linux and Kernel engineering https://bootlin.com