When a dyndbg classname is unknown to a kernel module (as before previous patch), the callsite is un-addressable via >control queries. The control-file displays this condition as "class unknown," currently. That spelling is sub-optimal/too-generic, so change it to "class:_UNKNOWN_" to loudly announce the erroneous situation, and to make it exceedingly greppable. NB: pr_debugs are only alterable via >control, and to protect class'd debug's from unintended alteration, "class name" must be given to change them. Classmaps map known classes to reserved .class_ids (the 1..64 val range per module). Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index f2c5e7910bb1..73ccf947d4aa 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -1154,7 +1154,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) if (class) seq_printf(m, " class:%s", class); else - seq_printf(m, " class unknown, _id:%d", dp->class_id); + seq_printf(m, " class:_UNKNOWN_ _id:%d", dp->class_id); } seq_puts(m, "\n"); -- 2.45.2

Classmaps are stored in an elf section/array, but are individually list-linked onto dyndbg's per-module ddebug_table for operation. This is unnecessary; even when ddebug_attach_classmap() is handling the builtin section (with classmaps for multiple builtin modules), its contents are ordered, so a module's possibly multiple classmaps will be consecutive in the section, and could be treated as a vector/block, since both start-address and subrange length are in the ddebug_info arg. IOW, this treats classmaps similarly to _ddebugs, which are already kept as vector-refs (address+len). So this changes: struct ddebug_class_map drops list-head link. struct ddebug_table drops the list-head maps, and gets: classes & num_classes for the start-address and num_classes, placed to improve struct packing. The loading: in ddebug_attach_module_classes(), replace the for-the-modname list-add loop, with a forloop that finds the module's subrange (start,length) of matching classmaps within the possibly builtin classmaps vector, and saves those to the ddebug_table. The reading/using: change list-foreach loops in ddebug_class_name() & ddebug_find_valid_class() to walk the array from start to length. Also: Move #define __outvar up, above an added use in a fn-prototype. Simplify ddebug_attach_module_classes args, ref has both address & len. no functional changes Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- include/linux/dynamic_debug.h | 1 - lib/dynamic_debug.c | 61 ++++++++++++++++++----------------- 2 files changed, 32 insertions(+), 30 deletions(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index b9afc7731b7c..2b0057058ecf 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -83,7 +83,6 @@ enum class_map_type { }; struct ddebug_class_map { - struct list_head link; struct module *mod; const char *mod_name; /* needed for builtins */ const char **class_names; diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 152b04c05981..46e4cdd8e6be 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -45,10 +45,11 @@ extern struct ddebug_class_map __start___dyndbg_classes[]; extern struct ddebug_class_map __stop___dyndbg_classes[]; struct ddebug_table { - struct list_head link, maps; + struct list_head link; const char *mod_name; - unsigned int num_ddebugs; struct _ddebug *ddebugs; + struct ddebug_class_map *classes; + unsigned int num_ddebugs, num_classes; }; struct ddebug_query { @@ -147,13 +148,15 @@ 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, int *class_id) + const char *class_string, + __outvar int *class_id) { struct ddebug_class_map *map; - int idx; + int i, idx; - list_for_each_entry(map, &dt->maps, link) { + for (map = dt->classes, i = 0; i < dt->num_classes; i++, map++) { idx = match_string(map->class_names, map->length, class_string); if (idx >= 0) { *class_id = idx + map->base; @@ -164,7 +167,6 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons return NULL; } -#define __outvar /* filled by callee */ /* * Search the tables for _ddebug's which match the given `query' and * apply the `flags' and `mask' to them. Returns number of matching @@ -1114,9 +1116,10 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) static const char *ddebug_class_name(struct ddebug_iter *iter, struct _ddebug *dp) { - struct ddebug_class_map *map; + struct ddebug_class_map *map = iter->table->classes; + int i, nc = iter->table->num_classes; - list_for_each_entry(map, &iter->table->maps, link) + for (i = 0; i < nc; i++, map++) if (class_in_range(dp->class_id, map)) return map->class_names[dp->class_id - map->base]; @@ -1200,30 +1203,31 @@ static const struct proc_ops proc_fops = { .proc_write = ddebug_proc_write }; -static void ddebug_attach_module_classes(struct ddebug_table *dt, - struct ddebug_class_map *classes, - int num_classes) +static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug_info *di) { struct ddebug_class_map *cm; - int i, j, ct = 0; + int i, nc = 0; - for (cm = classes, i = 0; i < num_classes; i++, cm++) { + /* + * 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++) { if (!strcmp(cm->mod_name, dt->mod_name)) { - - v2pr_info("class[%d]: module:%s base:%d len:%d ty:%d\n", i, - cm->mod_name, cm->base, cm->length, cm->map_type); - - for (j = 0; j < cm->length; j++) - v3pr_info(" %d: %d %s\n", j + cm->base, j, - cm->class_names[j]); - - list_add(&cm->link, &dt->maps); - ct++; + 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); + dt->classes = cm; + } + nc++; } } - if (ct) - vpr_info("module:%s attached %d classes\n", dt->mod_name, ct); + if (nc) { + dt->num_classes = nc; + vpr_info("module:%s attached %d classes\n", dt->mod_name, nc); + } } /* @@ -1256,10 +1260,9 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname) dt->num_ddebugs = di->num_descs; INIT_LIST_HEAD(&dt->link); - INIT_LIST_HEAD(&dt->maps); if (di->classes && di->num_classes) - ddebug_attach_module_classes(dt, di->classes, di->num_classes); + ddebug_attach_module_classes(dt, di); mutex_lock(&ddebug_lock); list_add_tail(&dt->link, &ddebug_tables); @@ -1372,8 +1375,8 @@ static void ddebug_remove_all_tables(void) mutex_lock(&ddebug_lock); while (!list_empty(&ddebug_tables)) { struct ddebug_table *dt = list_entry(ddebug_tables.next, - struct ddebug_table, - link); + struct ddebug_table, + link); ddebug_table_free(dt); } mutex_unlock(&ddebug_lock); -- 2.45.2

Split api-fn: param_set_dyndbg_classes(), adding modname param and passing NULL in from api-fn. The new arg allows caller to specify that only one module is affected by a prdbgs update. This selectivity will be used later to narrow the scope of changes made. no functional change. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 37 ++++++++++++++++++++++--------------- 1 file changed, 22 insertions(+), 15 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index a1fd2e9dbafb..4a48f830507f 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -711,18 +711,9 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa return 0; } -/** - * param_set_dyndbg_classes - class FOO >control - * @instr: string echo>d to sysfs, input depends on map_type - * @kp: kp->arg has state: bits/lvl, map, map_type - * - * Enable/disable prdbgs by their class, as given in the arguments to - * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative - * levels by bitpos. - * - * Returns: 0 or <0 if error. - */ -int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) +static int param_set_dyndbg_module_classes(const char *instr, + const struct kernel_param *kp, + const char *modnm) { const struct ddebug_class_param *dcp = kp->arg; const struct ddebug_class_map *map = dcp->map; @@ -759,8 +750,8 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); inrep &= CLASSMAP_BITMASK(map->length); } - v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, NULL); + 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: @@ -773,7 +764,7 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) 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)); - totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, NULL); + totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, modnm); *dcp->lvl = inrep; break; default: @@ -782,6 +773,22 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) vpr_info("%s: total matches: %d\n", KP_NAME(kp), totct); return 0; } + +/** + * param_set_dyndbg_classes - class FOO >control + * @instr: string echo>d to sysfs, input depends on map_type + * @kp: kp->arg has state: bits/lvl, map, map_type + * + * Enable/disable prdbgs by their class, as given in the arguments to + * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative + * levels by bitpos. + * + * Returns: 0 or <0 if error. + */ +int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) +{ + return param_set_dyndbg_module_classes(instr, kp, NULL); +} EXPORT_SYMBOL(param_set_dyndbg_classes); /** -- 2.45.2

currently, for verbose=3, these are logged (blank lines for clarity): dyndbg: query 0: "class DRM_UT_CORE +p" mod:* dyndbg: split into words: "class" "DRM_UT_CORE" "+p" dyndbg: op='+' dyndbg: flags=0x1 dyndbg: *flagsp=0x1 *maskp=0xffffffff dyndbg: parsed: func="" file="" module="" format="" lineno=0-0 class=... dyndbg: no matches for query dyndbg: no-match: func="" file="" module="" format="" lineno=0-0 class=... dyndbg: processed 1 queries, with 0 matches, 0 errs That is excessive, so this patch: - shrinks 3 lines of 2nd stanza to single line - drops 1st 2 lines of 3rd stanza 3rd line is like 1st, with result, not procedure. 2nd line is just status, retold in 4th, with more info. New output: dyndbg: query 0: "class DRM_UT_CORE +p" mod:* dyndbg: split into words: "class" "DRM_UT_CORE" "+p" dyndbg: op='+' flags=0x1 *flagsp=0x1 *maskp=0xffffffff dyndbg: no-match: func="" file="" module="" format="" lineno=0-0 class=... dyndbg: processed 1 queries, with 0 matches, 0 errs no functional change. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 4a48f830507f..368381dbd266 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -266,9 +266,6 @@ static int ddebug_change(const struct ddebug_query *query, } mutex_unlock(&ddebug_lock); - if (!nfound && verbose) - pr_info("no matches for query\n"); - return nfound; } @@ -501,7 +498,6 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) pr_err("bad flag-op %c, at start of %s\n", *str, str); return -EINVAL; } - v3pr_info("op='%c'\n", op); for (; *str ; ++str) { for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { @@ -515,7 +511,6 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) return -EINVAL; } } - v3pr_info("flags=0x%x\n", modifiers->flags); /* calculate final flags, mask based upon op */ switch (op) { @@ -531,7 +526,7 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) modifiers->flags = 0; break; } - v3pr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask); + v3pr_info("op='%c' flags=0x%x maskp=0x%x\n", op, modifiers->flags, modifiers->mask); return 0; } @@ -541,7 +536,7 @@ static int ddebug_exec_query(char *query_string, const char *modname) struct flag_settings modifiers = {}; struct ddebug_query query = {}; #define MAXWORDS 9 - int nwords, nfound; + int nwords; char *words[MAXWORDS]; nwords = ddebug_tokenize(query_string, words, MAXWORDS); @@ -559,10 +554,7 @@ static int ddebug_exec_query(char *query_string, const char *modname) return -EINVAL; } /* actually go and implement the change */ - nfound = ddebug_change(&query, &modifiers); - vpr_info_dq(&query, nfound ? "applied" : "no-match"); - - return nfound; + return ddebug_change(&query, &modifiers); } /* handle multiple queries in query string, continue on error, return -- 2.45.2

Change function's 1st arg-type, and deref in the caller. The fn doesn't need any other fields in the struct. no functional change. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 8320cadeb251..882354e1e78f 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -1120,12 +1120,12 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) #define class_in_range(class_id, map) \ (class_id >= map->base && class_id < map->base + map->length) -static const char *ddebug_class_name(struct ddebug_iter *iter, struct _ddebug *dp) +static const char *ddebug_class_name(struct ddebug_table *dt, struct _ddebug *dp) { - struct ddebug_class_map *map = iter->table->classes; - int i, nc = iter->table->num_classes; + struct ddebug_class_map *map = dt->classes; + int i; - for (i = 0; i < nc; i++, map++) + 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]; @@ -1159,7 +1159,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) seq_puts(m, "\""); if (dp->class_id != _DPRINTK_CLASS_DFLT) { - class = ddebug_class_name(iter, dp); + class = ddebug_class_name(iter->table, dp); if (class) seq_printf(m, " class:%s", class); else -- 2.45.2

When modprobing a module, dyndbg currently logs/says "add-module", and then "skipping" if the module has no prdbgs. Instead just check 1st and return quietly. no functional change Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index d4a0ae31d059..43a8e04b8599 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -1245,11 +1245,10 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname) { struct ddebug_table *dt; - v3pr_info("add-module: %s.%d sites\n", modname, di->num_descs); - if (!di->num_descs) { - v3pr_info(" skip %s\n", modname); + if (!di->num_descs) return 0; - } + + v3pr_info("add-module: %s %d sites\n", modname, di->num_descs); dt = kzalloc(sizeof(*dt), GFP_KERNEL); if (dt == NULL) { -- 2.45.2

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 <jim.cromie@gmail.com> --- 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 <jim.cromie@gmail.com> 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 <talgi@nvidia.com> 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 <jim.cromie@gmail.com> */ -#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 <linux/module.h> -/* 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_<CORE,DRIVER,KMS,etc>. + * + * 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 <jim.cromie@gmail.com> + */ + +#define TEST_DYNAMIC_DEBUG_SUBMOD +#include "test_dynamic_debug.c" -- 2.45.2

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

Treat comma as a token terminator, just like a space. This allows a user to avoid quoting hassles when spaces are otherwise needed: :#> modprobe drm dyndbg=class,DRM_UT_CORE,+p\;class,DRM_UT_KMS,+p or as a boot arg: drm.dyndbg=class,DRM_UT_CORE,+p # todo: support multi-query here Given the many ways a boot-line +args can be assembled and then passed in/down/around shell based tools, this may allow side-stepping all sorts of quoting hassles thru those layers. existing query format: modprobe test_dynamic_debug dyndbg="class D2_CORE +p" new format: modprobe test_dynamic_debug dyndbg=class,D2_CORE,+p Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Co-developed-by: Łukasz Bartosik <ukaszb@chromium.org> Signed-off-by: Łukasz Bartosik <ukaszb@chromium.org> --- lib/dynamic_debug.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index e9a95b0f3757..235d85765b63 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -290,6 +290,14 @@ static int ddebug_change(const struct ddebug_query *query, return nfound; } +static char *skip_spaces_and_commas(const char *str) +{ + str = skip_spaces(str); + while (*str == ',') + str = skip_spaces(++str); + return (char *)str; +} + /* * Split the buffer `buf' into space-separated words. * Handles simple " and ' quoting, i.e. without nested, @@ -303,8 +311,8 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords) while (*buf) { char *end; - /* Skip leading whitespace */ - buf = skip_spaces(buf); + /* Skip leading whitespace and comma */ + buf = skip_spaces_and_commas(buf); if (!*buf) break; /* oh, it was trailing whitespace */ if (*buf == '#') @@ -320,7 +328,7 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords) return -EINVAL; /* unclosed quote */ } } else { - for (end = buf; *end && !isspace(*end); end++) + for (end = buf; *end && !isspace(*end) && *end != ','; end++) ; if (end == buf) { pr_err("parse err after word:%d=%s\n", nwords, @@ -592,7 +600,8 @@ static int ddebug_exec_queries(char *query, const char *modname) if (split) *split++ = '\0'; - query = skip_spaces(query); + query = skip_spaces_and_commas(query); + if (!query || !*query || *query == '#') continue; -- 2.45.2

Since commit 85f7f6c0edb8 ("dynamic_debug: process multiple debug-queries on a line") Multi-query commands have been allowed: modprobe drm dyndbg="class DRM_UT_CORE +p; class DRM_UT_KMS +p" modprobe drm dyndbg=<<EOX class DRM_UT_CORE +p class DRM_UT_KMS +p EOX More recently, the need for quoting was avoided by treating a comma like a space/token-terminator: modprobe drm dyndbg=class,DRM_UT_CORE,+p\;class,DRM_UT_KMS,+p That works, but it needs the escaped semicolon, which is a shell special-char (one of the bash control operators), so it is brittle when passed in/down/around scripts. In particular, it fails when passed to vng (virtme-ng). So this patch adds '%' to the existing ';' and '\n' multi-command separators, which is more shell-friendly, so you can more fully avoid quoting and escaping hassles. NOTE: it does break format matching on '%' patterns: bash-5.2# ddcmd 'format "find-me: %foo" +p' [ 203.900581] dyndbg: read 26 bytes from userspace [ 203.900883] dyndbg: query 0: "format "find-me: " mod:* [ 203.901118] dyndbg: unclosed quote: find-me: [ 203.901355] dyndbg: tokenize failed [ 203.901529] dyndbg: query 1: "foo" +p" mod:* [ 203.901957] dyndbg: split into words: "foo"" "+p" [ 203.902243] dyndbg: op='+' flags=0x1 maskp=0xffffffff [ 203.902458] dyndbg: expecting pairs of match-spec <value> [ 203.902703] dyndbg: query parse failed [ 203.902871] dyndbg: processed 2 queries, with 0 matches, 2 errs bash: echo: write error: Invalid argument The '%' splits the input into 2 queries, and both fail. Given the limited utility of matching against the working parts of a format string "foo: %d bar %s", nothing is actually lost here. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 235d85765b63..dcec7b3657bb 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -596,7 +596,7 @@ static int ddebug_exec_queries(char *query, const char *modname) int i, errs = 0, exitcode = 0, rc, nfound = 0; for (i = 0; query; query = split) { - split = strpbrk(query, ";\n"); + split = strpbrk(query, "%;\n"); if (split) *split++ = '\0'; -- 2.45.2

Add mention of comma and percent delimiters into the respective paragraphs describing their equivalents: space and newline. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- .../admin-guide/dynamic-debug-howto.rst | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst index 742eb4230c6e..7b570f29ae98 100644 --- a/Documentation/admin-guide/dynamic-debug-howto.rst +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -73,16 +73,18 @@ Command Language Reference ========================== At the basic lexical level, a command is a sequence of words separated -by spaces or tabs. So these are all equivalent:: +by spaces, tabs, or commas. So these are all equivalent:: :#> ddcmd file svcsock.c line 1603 +p :#> ddcmd "file svcsock.c line 1603 +p" :#> ddcmd ' file svcsock.c line 1603 +p ' + :#> ddcmd file,svcsock.c,line,1603,+p -Command submissions are bounded by a write() system call. -Multiple commands can be written together, separated by ``;`` or ``\n``:: +Command submissions are bounded by a write() system call. Multiple +commands can be written together, separated by ``%``, ``;`` or ``\n``:: - :#> ddcmd "func pnpacpi_get_resources +p; func pnp_assign_mem +p" + :#> ddcmd func foo +p % func bar +p + :#> ddcmd func foo +p \; func bar +p :#> ddcmd <<"EOC" func pnpacpi_get_resources +p func pnp_assign_mem +p @@ -104,7 +106,6 @@ The match-spec's select *prdbgs* from the catalog, upon which to apply the flags-spec, all constraints are ANDed together. An absent keyword is the same as keyword "*". - A match specification is a keyword, which selects the attribute of the callsite to be compared, and a value to compare against. Possible keywords are::: @@ -128,7 +129,6 @@ keywords are::: ``line-range`` cannot contain space, e.g. "1-30" is valid range but "1 - 30" is not. - The meanings of each keyword are: func @@ -153,9 +153,11 @@ module The given string is compared against the module name of each callsite. The module name is the string as seen in ``lsmod``, i.e. without the directory or the ``.ko`` - suffix and with ``-`` changed to ``_``. Examples:: + suffix and with ``-`` changed to ``_``. + + Examples:: - module sunrpc + module,sunrpc # with ',' as token separator module nfsd module drm* # both drm, drm_kms_helper -- 2.45.2

When writing queries to >control, flags are parsed 1st, since they are the only required field. So if the flags draw an error, then keyword errors aren't reported. This can be mildly confusing/annoying, so explain it instead. This note could be moved up to just after the grammar id's the flags, and before the match-spec is detailed. Opinions ? Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- Documentation/admin-guide/dynamic-debug-howto.rst | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst index 7b570f29ae98..ccf3704f2143 100644 --- a/Documentation/admin-guide/dynamic-debug-howto.rst +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -106,6 +106,16 @@ The match-spec's select *prdbgs* from the catalog, upon which to apply the flags-spec, all constraints are ANDed together. An absent keyword is the same as keyword "*". +Note: because the match-spec can be empty, the flags are checked 1st, +then the pairs of keyword values. Flag errs will hide keyword errs: + + bash-5.2# ddcmd mod bar +foo + dyndbg: read 13 bytes from userspace + dyndbg: query 0: "mod bar +foo" mod:* + dyndbg: unknown flag 'o' + dyndbg: flags parse failed + dyndbg: processed 1 queries, with 0 matches, 1 errs + A match specification is a keyword, which selects the attribute of the callsite to be compared, and a value to compare against. Possible keywords are::: -- 2.45.2

Several tests are dependent upon config choices. Lets avoid failing where that is noise. The KCONFIG_CONFIG var exists to convey the config-file around. If the var names a file, read it and extract the relevant CONFIG items, and use them to skip the dependent tests, thus avoiding the fails that would follow, and the disruption to whatever CI is running these selftests. If the envar doesn't name a config-file, ".config" is assumed. CONFIG_DYNAMIC_DEBUG=y: basic-tests() and comma-terminator-tests() test for the presence of the builtin pr_debugs in module/main.c, which I deemed stable and therefore safe to count. That said, the test fails if only CONFIG_DYNAMIC_DEBUG_CORE=y is set. It could be rewritten to test against test-dynamic-debug.ko, but that just trades one config dependence for another. CONFIG_TEST_DYNAMIC_DEBUG=m As written, test_percent_splitting() modprobes test_dynamic_debug, enables several classes, and count them. It could be re-written to work for the builtin module also, but builtin test modules are not a common or desirable build/config. CONFIG_TEST_DYNAMIC_DEBUG=m && CONFIG_TEST_DYNAMIC_DEBUG_SUBMOD=m test_mod_submod() recaps the bug found in DRM-CI where drivers werent enabled by drm.debug=<bits>. It modprobes both test_dynamic_debug & test_dynamic_debug_submod, so it depends on a loadable modules config. It could be rewritten to work in a builtin parent config; DRM=y is common enough to be pertinent, but testing that config also wouldn't really test anything more fully than all-loadable modules, since they default together. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> fixup-kconfig --- .../dynamic_debug/dyndbg_selftest.sh | 45 ++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh b/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh index fccd2012b548..d09ef26b2308 100755 --- a/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh +++ b/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh @@ -11,6 +11,30 @@ CYAN="\033[0;36m" NC="\033[0;0m" error_msg="" +[ -e /proc/dynamic_debug/control ] || { + echo -e "${RED}: this test requires CONFIG_DYNAMIC_DEBUG=y ${NC}" + exit 0 # nothing to test here, no good reason to fail. +} + +# need info to avoid failures due to untestable configs + +[ -f "$KCONFIG_CONFIG" ] || KCONFIG_CONFIG=".config" +if [ -f "$KCONFIG_CONFIG" ]; then + echo "# consulting KCONFIG_CONFIG: $KCONFIG_CONFIG" + grep -q "CONFIG_DYNAMIC_DEBUG=y" $KCONFIG_CONFIG ; LACK_DD_BUILTIN=$? + grep -q "CONFIG_TEST_DYNAMIC_DEBUG=m" $KCONFIG_CONFIG ; LACK_TMOD=$? + grep -q "CONFIG_TEST_DYNAMIC_DEBUG_SUBMOD=m" $KCONFIG_CONFIG ; LACK_TMOD_SUBMOD=$? + if [ $V -eq 1 ]; then + echo LACK_DD_BUILTIN: $LACK_DD_BUILTIN + echo LACK_TMOD: $LACK_TMOD + echo LACK_TMOD_SUBMOD: $LACK_TMOD_SUBMOD + fi +else + LACK_DD_BUILTIN=0 + LACK_TMOD=0 + LACK_TMOD_SUBMOD=0 +fi + function vx () { echo $1 > /sys/module/dynamic_debug/parameters/verbose } @@ -192,6 +216,10 @@ function check_err_msg() { function basic_tests { echo -e "${GREEN}# BASIC_TESTS ${NC}" + if [ $LACK_DD_BUILTIN -eq 1 ]; then + echo "SKIP" + return + fi ddcmd =_ # zero everything (except class'd sites) check_match_ct =p 0 # there are several main's :-/ @@ -214,6 +242,10 @@ EOF function comma_terminator_tests { echo -e "${GREEN}# COMMA_TERMINATOR_TESTS ${NC}" + if [ $LACK_DD_BUILTIN -eq 1 ]; then + echo "SKIP" + return + fi # try combos of spaces & commas check_match_ct '\[params\]' 4 -r ddcmd module,params,=_ # commas as spaces @@ -226,9 +258,12 @@ function comma_terminator_tests { ddcmd =_ } - function test_percent_splitting { echo -e "${GREEN}# TEST_PERCENT_SPLITTING - multi-command splitting on % ${NC}" + if [ $LACK_TMOD -eq 1 ]; then + echo "SKIP" + return + fi ifrmmod test_dynamic_debug_submod ifrmmod test_dynamic_debug ddcmd =_ @@ -248,6 +283,14 @@ function test_percent_splitting { function test_mod_submod { echo -e "${GREEN}# TEST_MOD_SUBMOD ${NC}" + if [ $LACK_TMOD -eq 1 ]; then + echo "SKIP" + return + fi + if [ $LACK_TMOD_SUBMOD -eq 1 ]; then + echo "SKIP" + return + fi ifrmmod test_dynamic_debug_submod ifrmmod test_dynamic_debug ddcmd =_ -- 2.45.2

Incorrectly spelled CFLAGS- failed to add -DDYNAMIC_DEBUG_MODULE, which broke builds with: CONFIG_DRM_USE_DYNAMIC_DEBUG=y CONFIG_DYNAMIC_DEBUG_CORE=y CONFIG_DYNAMIC_DEBUG=n Also add subdir-ccflags so that all drivers pick up the addition. Fixes: 84ec67288c10 ("drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro") Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index f9ca4f8fa6c5..78b464cd4348 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -3,7 +3,8 @@ # Makefile for the drm device driver. This driver provides support for the # Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher. -CFLAGS-$(CONFIG_DRM_USE_DYNAMIC_DEBUG) += -DDYNAMIC_DEBUG_MODULE +ccflags-$(CONFIG_DRM_USE_DYNAMIC_DEBUG) += -DDYNAMIC_DEBUG_MODULE +subdir-ccflags-$(CONFIG_DRM_USE_DYNAMIC_DEBUG) += -DDYNAMIC_DEBUG_MODULE # Unconditionally enable W=1 warnings locally # --- begin copy-paste W=1 warnings from scripts/Makefile.extrawarn -- 2.45.2

Invoke DYNDBG_CLASSMAP_PARAM to hook drm.debug (__drm_debug) to the DRM_UT_* classmap, replacing the ad-hoc wiring previously doing it. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/drm_print.c | 8 ++------ include/drm/drm_print.h | 6 ++++-- 2 files changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c index 41f167082042..c7455f2076b4 100644 --- a/drivers/gpu/drm/drm_print.c +++ b/drivers/gpu/drm/drm_print.c @@ -69,12 +69,8 @@ DRM_CLASSMAP_DEFINE(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, "DRM_UT_DP", "DRM_UT_DRMRES"); -static struct ddebug_class_param drm_debug_bitmap = { - .bits = &__drm_debug, - .flags = "p", - .map = &drm_debug_classes, -}; -module_param_cb(debug, ¶m_ops_dyndbg_classes, &drm_debug_bitmap, 0600); +DRM_CLASSMAP_PARAM_REF(debug, __drm_debug, drm_debug_classes, p); + #endif void __drm_puts_coredump(struct drm_printer *p, const char *str) diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h index b467ee67a281..aa3708c7b6d8 100644 --- a/include/drm/drm_print.h +++ b/include/drm/drm_print.h @@ -141,11 +141,13 @@ enum drm_debug_category { }; #ifdef CONFIG_DRM_USE_DYNAMIC_DEBUG -#define DRM_CLASSMAP_DEFINE(...) DYNDBG_CLASSMAP_DEFINE(__VA_ARGS__) -#define DRM_CLASSMAP_USE(name) DYNDBG_CLASSMAP_USE(name) +#define DRM_CLASSMAP_DEFINE(...) DYNDBG_CLASSMAP_DEFINE(__VA_ARGS__) +#define DRM_CLASSMAP_USE(name) DYNDBG_CLASSMAP_USE(name) +#define DRM_CLASSMAP_PARAM_REF(...) DYNDBG_CLASSMAP_PARAM_REF(__VA_ARGS__) #else #define DRM_CLASSMAP_DEFINE(...) #define DRM_CLASSMAP_USE(name) +#define DRM_CLASSMAP_PARAM_REF(...) #endif static inline bool drm_debug_enabled_raw(enum drm_debug_category category) -- 2.45.2

Following the dyndbg-api-fix, replace DECLARE_DYNDBG_CLASSMAP with DRM_CLASSMAP_USE. This refs the defined & exported classmap, rather than re-declaring it redundantly, and error-prone-ly. This resolves the appearance of "class:_UNKNOWN_" in the control file for the driver's drm_dbg()s. Fixes: f158936b60a7 ("drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.") Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/i915/i915_params.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 8c00169e3ab7..a8f51f138895 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -29,17 +29,7 @@ #include "i915_params.h" #include "i915_drv.h" -DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0, - "DRM_UT_CORE", - "DRM_UT_DRIVER", - "DRM_UT_KMS", - "DRM_UT_PRIME", - "DRM_UT_ATOMIC", - "DRM_UT_VBL", - "DRM_UT_STATE", - "DRM_UT_LEASE", - "DRM_UT_DP", - "DRM_UT_DRMRES"); +DRM_CLASSMAP_USE(drm_debug_classes); #define i915_param_named(name, T, perm, desc) \ module_param_named(name, i915_modparams.name, T, perm); \ -- 2.45.2

Following the dyndbg-api-fix, replace DECLARE_DYNDBG_CLASSMAP with DRM_CLASSMAP_USE. This refs the defined & exported classmap, rather than re-declaring it redundantly, and error-prone-ly. This resolves the appearance of "class:_UNKNOWN_" in the control file for the driver's drm_dbg()s. Fixes: f158936b60a7 ("drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.") Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/display/drm_dp_helper.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index 79a615667aab..26e01845531e 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -41,17 +41,7 @@ #include "drm_dp_helper_internal.h" -DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0, - "DRM_UT_CORE", - "DRM_UT_DRIVER", - "DRM_UT_KMS", - "DRM_UT_PRIME", - "DRM_UT_ATOMIC", - "DRM_UT_VBL", - "DRM_UT_STATE", - "DRM_UT_LEASE", - "DRM_UT_DP", - "DRM_UT_DRMRES"); +DRM_CLASSMAP_USE(drm_debug_classes); struct dp_aux_backlight { struct backlight_device *base; -- 2.45.2

With CONFIG_DRM_USE_DYNAMIC_DEBUG=y, I'm getting an unused variable warning/error on 'category', though the usage follows immediately, in drm_debug_enabled(). This drops the local var and refs the field directly in the macro-call, which avoids the warning. For static-key optimized dyndbg, the macro doesn't actually check the category, since the static-key patches in the proper state. This is also likely why the auto var appears to be unused by the compiler. commit 9fd6f61a297e ("drm/print: add drm_dbg_printer() for drm device specific printer") CC: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/drm_print.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c index c7455f2076b4..0980210a5146 100644 --- a/drivers/gpu/drm/drm_print.c +++ b/drivers/gpu/drm/drm_print.c @@ -183,11 +183,10 @@ void __drm_printfn_dbg(struct drm_printer *p, struct va_format *vaf) { const struct drm_device *drm = p->arg; const struct device *dev = drm ? drm->dev : NULL; - enum drm_debug_category category = p->category; const char *prefix = p->prefix ?: ""; const char *prefix_pad = p->prefix ? " " : ""; - if (!__drm_debug_enabled(category)) + if (!__drm_debug_enabled(p->category)) return; /* Note: __builtin_return_address(0) is useless here. */ -- 2.45.2

virtio_gpu has 10 DRM_UT_CORE debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module has class'd debugs. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/virtio/virtgpu_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c index 188e126383c2..d69d517de2a3 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.c +++ b/drivers/gpu/drm/virtio/virtgpu_drv.c @@ -44,6 +44,8 @@ static const struct drm_driver driver; static int virtio_gpu_modeset = -1; +DRM_CLASSMAP_USE(drm_debug_classes); + MODULE_PARM_DESC(modeset, "Disable/Enable modesetting"); module_param_named(modeset, virtio_gpu_modeset, int, 0400); -- 2.45.2

tiny/bochs has 5 DRM_UT_* debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module has class'd debugs. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/tiny/bochs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/tiny/bochs.c b/drivers/gpu/drm/tiny/bochs.c index c23c9f0cf49c..ee98fab5597e 100644 --- a/drivers/gpu/drm/tiny/bochs.c +++ b/drivers/gpu/drm/tiny/bochs.c @@ -54,6 +54,8 @@ static int bochs_modeset = -1; static int defx = 1024; static int defy = 768; +DRM_CLASSMAP_USE(drm_debug_classes); + module_param_named(modeset, bochs_modeset, int, 0444); MODULE_PARM_DESC(modeset, "enable/disable kernel modesetting"); -- 2.45.2

The gma500 has 126 DRM_UT_* debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module has class'd debugs. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/gma500/psb_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/gma500/psb_drv.c b/drivers/gpu/drm/gma500/psb_drv.c index 8b64f61ffaf9..5e03ac7ff433 100644 --- a/drivers/gpu/drm/gma500/psb_drv.c +++ b/drivers/gpu/drm/gma500/psb_drv.c @@ -39,6 +39,8 @@ static const struct drm_driver driver; static int psb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent); +DRM_CLASSMAP_USE(drm_debug_classes); + /* * The table below contains a mapping of the PCI vendor ID and the PCI Device ID * to the different groups of PowerVR 5-series chip designs -- 2.45.2

The vmwgfx driver has a number of DRM_UT_* debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module uses them. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c index 823d8d2da17c..fd6cd62608a9 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c @@ -277,6 +277,8 @@ static int vmw_probe(struct pci_dev *, const struct pci_device_id *); static int vmwgfx_pm_notifier(struct notifier_block *nb, unsigned long val, void *ptr); +DRM_CLASSMAP_USE(drm_debug_classes); + MODULE_PARM_DESC(restrict_iommu, "Try to limit IOMMU usage for TTM pages"); module_param_named(restrict_iommu, vmw_restrict_iommu, int, 0600); MODULE_PARM_DESC(force_coherent, "Force coherent TTM pages"); -- 2.45.2

The udl driver has a number of DRM_UT_* debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module uses them. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/udl/udl_main.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/udl/udl_main.c b/drivers/gpu/drm/udl/udl_main.c index 3ebe2ce55dfd..ba57c14454e5 100644 --- a/drivers/gpu/drm/udl/udl_main.c +++ b/drivers/gpu/drm/udl/udl_main.c @@ -19,6 +19,8 @@ #define NR_USB_REQUEST_CHANNEL 0x12 +DRM_CLASSMAP_USE(drm_debug_classes); + #define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE) #define WRITES_IN_FLIGHT (20) #define MAX_VENDOR_DESCRIPTOR_SIZE 256 -- 2.45.2

The gud driver has a number of DRM_UT_* debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module uses them. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/gud/gud_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/gud/gud_drv.c b/drivers/gpu/drm/gud/gud_drv.c index 9d7bf8ee45f1..5b555045fce4 100644 --- a/drivers/gpu/drm/gud/gud_drv.c +++ b/drivers/gpu/drm/gud/gud_drv.c @@ -31,6 +31,8 @@ #include "gud_internal.h" +DRM_CLASSMAP_USE(drm_debug_classes); + /* Only used internally */ static const struct drm_format_info gud_drm_format_r1 = { .format = GUD_DRM_FORMAT_R1, -- 2.45.2

The drm_gem_shmem_helper driver has a number of DRM_UT_* debugs, make them controllable when CONFIG_DRM_USE_DYNAMIC_DEBUG=y by telling dyndbg that the module uses them. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 53c003983ad1..2b269ae9ea18 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -22,6 +22,8 @@ #include <drm/drm_prime.h> #include <drm/drm_print.h> +DRM_CLASSMAP_USE(drm_debug_classes); + MODULE_IMPORT_NS(DMA_BUF); /** -- 2.45.2

The DYNDBG_CLASSMAP_DEFINE expects a list of classnames, and maps them to consecutive classids starting at _base. That 1- list-of-classnames can be syntactically replaced by a 2- designated-initializers-list/map. But this creates ambiguity. The 1st thing the macro does: static const char *_var##_classnames[] = { __VA_ARGS__ }; This construct accepts either list form, cannot distinguish between them, and they place data differently. 1. puts the string values into array[0..N-1] 2. puts them into array[_base..N+_base-1] 2 wastes 0.._base-1 indices, and more importantly, also spec's _base twice: as a parameter, and then in the designated-initializers-list/map. Further, the code is written for a contiguous range of classnames and classids, and passing a map allows casual violation of this reasonable design choice. In particular, DRM_UT_* is a contiguous range, and each maps to a bit in drm.debug. The macro interface shouldn't suggest a sparse map is possible. So reword DYNDBG_CLASSMAP_* macro kdoc to more actively guide reader away from designated initializers here. TBD probably squash this back into the patchset. CC: ville.syrjala@linux.intel.com Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- include/linux/dynamic_debug.h | 52 +++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 21 deletions(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index c958085e0df4..d75a5d3ae388 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -80,15 +80,22 @@ struct ddebug_class_map { enum ddebug_class_map_type map_type; }; +/* + * modules using dyndbg-classmaps must invoke either + */ /** - * DYNDBG_CLASSMAP_DEFINE - define a set of debug-classes used by a module. + * DYNDBG_CLASSMAP_DEFINE - define 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_* + * @_type: enum ddebug_class_map_type: DISJOINT - independent, LEVEL - v2>v1 + * @_base: reserve N classids starting at _base, to split 0..62 classid space + * @classes: names of the N classes. * - * Defines and exports a struct ddebug_class_map whose @classes are - * used to validate a "class FOO .." >control command on the module + * This tells dyndbg what classids the module is using, by mapping + * names onto them. This qualifies "class NAME" >controls on the + * defining module, ignoring unknown names. + * + * The @classes also name the bits 0.. in any CLASSMAP_PARAM referring + * to the classmap. */ #define __DYNDBG_CLASSMAP_DEFINE(_var, _maptype, _base, ...) \ static const char *_var##_classnames[] = { __VA_ARGS__ }; \ @@ -131,9 +138,9 @@ struct ddebug_class_user { * 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. + * 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)) @@ -165,27 +172,30 @@ struct ddebug_class_param { }; /** - * 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' + * DYNDBG_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 - * classmap. Keeps bits in a private/static + * exported classmap, with bits 0..N-1 mapped to the classes named. + * This version keeps class-state in a private long int. */ #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' + * DYNDBG_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 classmap, keeping bitvec in user @_bits. - * This lets drm use __drm_debug elsewhere too. + * 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 DYNDBG_CLASSMAP_PARAM_REF(_name, _bits, _var, _flags) \ __DYNDBG_CLASSMAP_PARAM(_name, _bits, _var, _flags) -- 2.45.2