move the DYNDBG_CLASSMAP_PARAM macro from test-dynamic-debug.c into the header, and refine it, by distinguishing the 2 use cases: 1.DYNDBG_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.DYNDBG_CLASSMAP_PARAM new user (test_dynamic_debug) doesn't need to share state, decls a static long unsigned int to store the bitvec. __DYNDBG_CLASSMAP_PARAM bottom layer - allocate,init a ddebug-class-param, module-param-cb. Also clean up and improve comments in test-code, and add MODULE_DESCRIPTIONs. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- fixup drm-print.h add PARAM_REF forwarding macros with DYNDBG_CLASSMAP_PARAM_REF in the API, add DRM_ variant --- include/linux/dynamic_debug.h | 37 ++++++++++++++++- lib/dynamic_debug.c | 70 ++++++++++++++++++++++----------- lib/test_dynamic_debug.c | 50 +++++++++-------------- lib/test_dynamic_debug_submod.c | 9 ++++- 4 files changed, 110 insertions(+), 56 deletions(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index 189e3f60c31a..4a9b9cd53eb7 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -91,7 +91,7 @@ struct ddebug_class_map { * used to validate a "class FOO .." >control command on the module */ #define __DYNDBG_CLASSMAP_DEFINE(_var, _maptype, _base, ...) \ - const char *_var##_classnames[] = { __VA_ARGS__ }; \ + static const char *_var##_classnames[] = { __VA_ARGS__ }; \ struct ddebug_class_map __aligned(8) __used \ __section("__dyndbg_classes") _var = { \ .mod = THIS_MODULE, \ @@ -164,6 +164,41 @@ struct ddebug_class_param { const struct ddebug_class_map *map; }; +/** + * DYNDBG_CLASSMAP_PARAM - wrap a dyndbg-classmap with a controlling sys-param + * @_name sysfs node name + * @_var name of the struct classmap var defining the controlled classes + * @_flags flags to be toggled, typically just 'p' + * + * Creates a sysfs-param to control the classes defined by the + * classmap. Keeps bits in a private/static + */ +#define DYNDBG_CLASSMAP_PARAM(_name, _var, _flags) \ + static unsigned long _name##_bvec; \ + __DYNDBG_CLASSMAP_PARAM(_name, _name##_bvec, _var, _flags) + +/** + * DYNDBG_CLASSMAP_PARAM_REF - wrap a dyndbg-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 struct classmap var defining the controlled classes + * @_flags flags to be toggled, typically just 'p' + * + * Creates a sysfs-param to control the classmap, keeping bitvec in user @_bits. + * This lets drm use __drm_debug elsewhere too. + */ +#define DYNDBG_CLASSMAP_PARAM_REF(_name, _bits, _var, _flags) \ + __DYNDBG_CLASSMAP_PARAM(_name, _bits, _var, _flags) + +#define __DYNDBG_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 9150e0e5145f..e9a95b0f3757 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -657,6 +657,30 @@ 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 *modnm) @@ -675,26 +699,15 @@ 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, modnm ?: "*", KP_NAME(kp)); totct += ddebug_apply_class_bitmap(dcp, &inrep, *dcp->bits, modnm); *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)); @@ -1161,16 +1174,27 @@ static const char * const ddebug_classmap_typenames[] = { ddebug_classmap_typenames[_cm->map_type]); \ }) -static void ddebug_sync_classbits(const struct ddebug_class_param *dcp, const char *modname) +static void ddebug_sync_classbits(const struct kernel_param *kp, 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); + struct ddebug_class_param *dcp = kp->arg; + unsigned long new_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, @@ -1185,9 +1209,9 @@ static void ddebug_match_apply_kparam(const struct kernel_param *kp, 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); + v2pr_info(" found kp:%s =0x%lx", kp->name, *dcp->bits); + vpr_cm_info(map, " mapped to:"); + ddebug_sync_classbits(kp, modnm); } } diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c index ff9b879286d5..b3c6f90b9fe8 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 <jim.cromie@gmail.com> @@ -35,24 +36,8 @@ 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 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) -#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. + * Demonstrate/test both types of classmaps, each with a sys-param. * * Each is 3 part: client-enum decl, _DEFINE, _PARAM. * Declare them in blocks to show patterns of use (repetitions and @@ -64,7 +49,7 @@ module_param_cb(do_prints, ¶m_ops_do_prints, NULL, 0600); * 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 + * Declare all enums now, for different types */ /* numeric input, independent bits */ @@ -83,12 +68,15 @@ enum cat_disjoint_bits { /* numeric verbosity, V2 > V1 related */ enum cat_level_num { V0 = 14, V1, V2, V3, V4, V5, V6, V7 }; -/* recapitulate DRM's parent(drm.ko) <-- _submod(drivers,helpers) */ +/* + * 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. */ DYNDBG_CLASSMAP_DEFINE(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, D2_CORE, @@ -107,19 +95,18 @@ 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 + * 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. */ - -DYNDBG_CLASSMAP_PARAM(disjoint_bits, p); -DYNDBG_CLASSMAP_PARAM(level_num, p); +DYNDBG_CLASSMAP_PARAM(p_disjoint_bits, map_disjoint_bits, p); +DYNDBG_CLASSMAP_PARAM(p_level_num, map_level_num, p); #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. */ - DYNDBG_CLASSMAP_USE(map_disjoint_bits); DYNDBG_CLASSMAP_USE(map_level_num); @@ -180,5 +167,6 @@ 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 <jim.cromie@gmail.com>"); MODULE_LICENSE("GPL"); diff --git a/lib/test_dynamic_debug_submod.c b/lib/test_dynamic_debug_submod.c index 9a893402ce1a..0d15f3ffe466 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 <jim.cromie@gmail.com> @@ -8,3 +11,7 @@ #define TEST_DYNAMIC_DEBUG_SUBMOD #include "test_dynamic_debug.c" + +MODULE_DESCRIPTION("test/demonstrate dynamic-debug subsystem support"); +MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>"); +MODULE_LICENSE("GPL"); -- 2.45.2