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[73.78.62.130]) by smtp.googlemail.com with ESMTPSA id 8926c6da1cb9f-4c210f23f1csm75301173.102.2024.07.16.11.58.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Jul 2024 11:58:43 -0700 (PDT) From: Jim Cromie To: linux-kernel@vger.kernel.org, jbaron@akamai.com, gregkh@linuxfoundation.org, daniel.vetter@ffwll.ch, tvrtko.ursulin@linux.intel.com, jani.nikula@intel.com, ville.syrjala@linux.intel.com Cc: ukaszb@chromium.org, linux@rasmusvillemoes.dk, joe@perches.com, mcgrof@kernel.org, seanpaul@chromium.org, robdclark@gmail.com, groeck@google.com, yanivt@google.com, bleung@google.com, linux-doc@vger.kernel.org, dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, kernelnewbies@kernelnewbies.org, Jim Cromie Subject: [PATCH v9-resend 15/54] dyndbg-API: fix DECLARE_DYNDBG_CLASSMAP Date: Tue, 16 Jul 2024 12:57:27 -0600 Message-ID: <20240716185806.1572048-16-jim.cromie@gmail.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716185806.1572048-1-jim.cromie@gmail.com> References: <20240716185806.1572048-1-jim.cromie@gmail.com> MIME-Version: 1.0 X-Mailman-Approved-At: Wed, 17 Jul 2024 15:01:12 +0000 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" 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. Worse, it causes the CONFIG_DRM_USE_DYNAMIC_DEBUG=Y regression; 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 reuses a renamed DECLARE_DYNDBG_CLASSMAP to construct the struct classmap variable, but it drops 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" args * fixes 2nd-defn problem * creates a ddebug_class_user record in new __dyndbg_class_users section this allows ddebug_add_module(etal) to handle them per-module. 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. 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 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 more fields to keep the new section with the others: 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 the 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. DEBUG details: ``#define DEBUG`` in src enables all pr_debugs after it, including any class'd pr_debugs; its not necessarily all-or-nothing, unless you do the define in a header. Also, the only way to disable a class'd pr_debug is via the classmap-kparam or using "class foo" in control queries, to address the classes by name. NB: this patch ignores a checkpatch do-while warning; which is wrong for declarative macros like these: arch/powerpc/platforms/cell/spu_base.c 48:static DEFINE_SPINLOCK(spu_lock); 62:static DEFINE_SPINLOCK(spu_full_list_lock); 63:static DEFINE_MUTEX(spu_full_list_mutex); Fixes: aad0214f3026 ("dyndbg: add DECLARE_DYNDBG_CLASSMAP macro") Signed-off-by: Jim Cromie --- 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 --- MAINTAINERS | 2 +- include/asm-generic/vmlinux.lds.h | 1 + include/linux/dynamic_debug.h | 62 ++++++++-- kernel/module/main.c | 3 + lib/Kconfig.debug | 24 +++- lib/Makefile | 3 + lib/dynamic_debug.c | 184 ++++++++++++++++++++++++++---- lib/test_dynamic_debug.c | 111 ++++++++++++------ lib/test_dynamic_debug_submod.c | 10 ++ 9 files changed, 332 insertions(+), 68 deletions(-) create mode 100644 lib/test_dynamic_debug_submod.c diff --git a/MAINTAINERS b/MAINTAINERS index 958e935449e5..eb8312ea681f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7684,7 +7684,7 @@ 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 5703526d6ebf..05fbf9f05eb4 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -367,6 +367,7 @@ /* 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..189e3f60c31a 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -72,8 +72,8 @@ enum ddebug_class_map_type { }; 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; const char **class_names; const int length; const int base; /* index of 1st .class_id, allows split/shared space */ @@ -81,11 +81,34 @@ 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 a set of debug-classes used by a module. + * @_var: name of the classmap, exported for other modules coordinated use. + * @_type: enum ddebug_class_map_type, chooses bits/verbose, numeric/names. + * @_base: offset of 1st class-name, used to share 0..62 classid space + * @classes: vals are stringified enum-vals, like DRM_UT_* + * + * Defines and exports a struct ddebug_class_map whose @classes are + * used to validate a "class FOO .." >control command on the module + */ +#define __DYNDBG_CLASSMAP_DEFINE(_var, _maptype, _base, ...) \ + const char *_var##_classnames[] = { __VA_ARGS__ }; \ + struct ddebug_class_map __aligned(8) __used \ + __section("__dyndbg_classes") _var = { \ + .mod = THIS_MODULE, \ + .mod_name = KBUILD_MODNAME, \ + .base = _base, \ + .map_type = _maptype, \ + .length = ARRAY_SIZE(_var##_classnames), \ + .class_names = _var##_classnames, \ + } +#define DYNDBG_CLASSMAP_DEFINE(_var, ...) \ + __DYNDBG_CLASSMAP_DEFINE(_var, __VA_ARGS__); \ + EXPORT_SYMBOL(_var) + +/* + * XXX: keep this until DRM adapts to use the DEFINE/USE api, it + * differs from __DYNDBG_CLASSMAP_DEFINE only in the static on the + * struct decl. */ #define DECLARE_DYNDBG_CLASSMAP(_var, _maptype, _base, ...) \ static const char *_var##_classnames[] = { __VA_ARGS__ }; \ @@ -99,12 +122,37 @@ struct ddebug_class_map { .class_names = _var##_classnames, \ } +struct ddebug_class_user { + char *user_mod_name; + struct ddebug_class_map *map; +}; + +/** + * DYNDBG_CLASSMAP_USE - refer to a classmap, DEFINEd elsewhere. + * @_var: name of the exported classmap var + * + * This registers a module's use of another module's classmap defn, so + * dyndbg can authorize "class DRM_CORE ..." >control commands upon + * this module. + */ +#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 = { \ + .user_mod_name = KBUILD_MODNAME, \ + .map = &(_var), \ + } + /* 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 { diff --git a/kernel/module/main.c b/kernel/module/main.c index d18a94b973e1..49329ca1df93 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -2235,6 +2235,9 @@ 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 59b6765d86b8..8662e26aceac 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2831,12 +2831,26 @@ 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 30337431d10e..81afaa5b756e 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -82,6 +82,7 @@ obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o obj-$(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-$(CONFIG_TEST_SCANF) += test_scanf.o @@ -224,6 +225,8 @@ obj-$(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 d5701207febc..9150e0e5145f 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 { @@ -148,21 +151,39 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg) query->first_lineno, query->last_lineno, query->class_string); } +#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); \ + }) + #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) { 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; + vpr_dt_info(dt, "good-class: %s.%s ", map->mod_name, class_string); return map; } } + 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) { + *class_id = idx + cli->map->base; + vpr_dt_info(dt, "class-ref: %s.%s ", + cli->user_mod_name, class_string); + return cli->map; + } + } *class_id = -ENOENT; return NULL; } @@ -559,7 +580,7 @@ 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 +709,12 @@ 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 +1059,17 @@ 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 +1150,134 @@ static const struct proc_ops proc_fops = { .proc_write = ddebug_proc_write }; +static const char * const ddebug_classmap_typenames[] = { + "DISJOINT_BITS", "LEVEL_NUM" +}; + +#define vpr_cm_info(cm_p, msg_p, ...) ({ \ + struct ddebug_class_map const *_cm = cm_p; \ + v2pr_info(msg_p " module:%s base:%d len:%d type:%s\n", ##__VA_ARGS__, \ + _cm->mod_name, _cm->base, _cm->length, \ + ddebug_classmap_typenames[_cm->map_type]); \ + }) + +static void ddebug_sync_classbits(const struct ddebug_class_param *dcp, const char *modname) +{ + /* 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("found kp:%s =0x%lx", kp->name, *dcp->bits); + vpr_cm_info(map, "mapped to:"); + ddebug_sync_classbits(dcp, 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 class:"); + /* 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 class:"); + 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, 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->user_mod_name)) + continue; + + if (!strcmp(cli->user_mod_name, dt->mod_name)) { + + vpr_cm_info(cli->map, "class_ref[%d] %s -> %s", i, + cli->user_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->user_mod_name); + + vpr_dt_info(dt, "attach-client-module: "); } /* @@ -1158,6 +1287,8 @@ 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 +1312,20 @@ 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 +1475,10 @@ 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 9e950a911b6c..ff9b879286d5 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) +/* + * 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, + 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(); } 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"