From 7deabd67498869640c937c9bd83472574b7dea0b Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Fri, 3 Mar 2023 11:50:56 -0500 Subject: dyndbg: use the module notifier callbacks Bring dynamic debug in line with other subsystems by using the module notifier callbacks. This results in a net decrease in core module code. Additionally, Jim Cromie has a new dynamic debug classmap feature, which requires that jump labels be initialized prior to dynamic debug. Specifically, the new feature toggles a jump label from the existing dynamic_debug_setup() function. However, this does not currently work properly, because jump labels are initialized via the 'module_notify_list' notifier chain, which is invoked after the current call to dynamic_debug_setup(). Thus, this patch ensures that jump labels are initialized prior to dynamic debug by setting the dynamic debug notifier priority to 0, while jump labels have the higher priority of 1. Tested by Jim using his new test case, and I've verfied the correct printing via: # modprobe test_dynamic_debug dyndbg. Link: https://lore.kernel.org/lkml/20230113193016.749791-21-jim.cromie@gmail.com/ Reported-by: kernel test robot Link: https://lore.kernel.org/oe-kbuild-all/202302190427.9iIK2NfJ-lkp@intel.com/ Tested-by: Jim Cromie Reviewed-by: Vincenzo Palazzo Cc: Peter Zijlstra CC: Jim Cromie Cc: Luis Chamberlain Cc: Greg Kroah-Hartman Signed-off-by: Jason Baron Signed-off-by: Luis Chamberlain --- include/linux/dynamic_debug.h | 13 ------------- 1 file changed, 13 deletions(-) (limited to 'include/linux/dynamic_debug.h') diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index 41682278d2e8..f401414341fb 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -130,9 +130,6 @@ struct ddebug_class_param { #if defined(CONFIG_DYNAMIC_DEBUG_CORE) -int ddebug_add_module(struct _ddebug_info *dyndbg, const char *modname); - -extern int ddebug_remove_module(const char *mod_name); extern __printf(2, 3) void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); @@ -304,16 +301,6 @@ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp); #include #include -static inline int ddebug_add_module(struct _ddebug_info *dinfo, const char *modname) -{ - return 0; -} - -static inline int ddebug_remove_module(const char *mod) -{ - return 0; -} - static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *modname) { -- cgit v1.2.3-70-g09d2 From 7ce93729091dff24e6a1c3578b58b36f4b1cf10a Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Fri, 10 Mar 2023 16:27:28 -0500 Subject: dyndbg: cleanup dynamic usage in ib_srp.c Currently, in dynamic_debug.h we only provide DEFINE_DYNAMIC_DEBUG_METADATA() and DYNAMIC_DEBUG_BRANCH() definitions if CONFIG_DYNAMIC_CORE is enabled. Thus, drivers such as infiniband srp (see: drivers/infiniband/ulp/srp/ib_srp.c) must provide their own definitions for !CONFIG_DYNAMIC_CORE. Thus, let's move this !CONFIG_DYNAMIC_CORE case into dynamic_debug.h. However, the dynamic debug interfaces should really only be defined if CONFIG_DYNAMIC_DEBUG is set or CONFIG_DYNAMIC_CORE is set along with DYNAMIC_DEBUG_MODULE, (see: Documentation/admin-guide/dynamic-debug-howto.rst). Thus, the undefined case becomes: !((CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_CORE && DYNAMIC_DEBUG_MODULE)). With those changes in place, we can remove the !CONFIG_DYNAMIC_CORE case from ib_srp.c This change was prompted by a build breakeage in ib_srp.c stemming from the inclusion of dynamic_debug.h unconditionally in module.h, due to commit 7deabd674988 ("dyndbg: use the module notifier callbacks"). In that case, if we have CONFIG_DYNAMIC_CORE=y and CONFIG_DYNAMIC_DEBUG=n then the definitions for DEFINE_DYNAMIC_DEBUG_METADATA() and DYNAMIC_DEBUG_BRANCH() are defined once in ib_srp.c and then again in the dynamic_debug.h. This had been working prior to the above referenced commit because dynamic_debug.h was only pulled into ib_srp.c conditinally via printk.h if CONFIG_DYNAMIC_DEBUG was set. Also, the exported functions in lib/dynamic_debug.c itself may not have a prototype if CONFIG_DYNAMIC_DEBUG=n and CONFIG_DYNAMIC_CORE=y. This would trigger the -Wmissing-prototypes warning. The exported functions are behind (include/linux/dynamic_debug.h): if defined(CONFIG_DYNAMIC_DEBUG) || \ (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) Thus, by adding -DDYNAMIC_CONFIG_MODULE to the lib/Makefile we can ensure that the exported functions have a prototype in all cases, since lib/dynamic_debug.c is built whenever CONFIG_DYNAMIC_DEBUG_CORE=y. Fixes: 7deabd674988 ("dyndbg: use the module notifier callbacks") Reported-by: kernel test robot Link: https://lore.kernel.org/oe-kbuild-all/202303071444.sIbZTDCy-lkp@intel.com/ Signed-off-by: Jason Baron [mcgrof: adjust commit log, and remove urldefense from URL] Signed-off-by: Luis Chamberlain --- drivers/infiniband/ulp/srp/ib_srp.c | 5 ---- include/linux/dynamic_debug.h | 59 +++++++++++++++++++++++-------------- lib/Makefile | 3 ++ 3 files changed, 40 insertions(+), 27 deletions(-) (limited to 'include/linux/dynamic_debug.h') diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index df21b30b7735..40ba2c6927c6 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -62,11 +62,6 @@ MODULE_AUTHOR("Roland Dreier"); MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator"); MODULE_LICENSE("Dual BSD/GPL"); -#if !defined(CONFIG_DYNAMIC_DEBUG) -#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) -#define DYNAMIC_DEBUG_BRANCH(descriptor) false -#endif - static unsigned int srp_sg_tablesize; static unsigned int cmd_sg_entries; static unsigned int indirect_sg_entries; diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index f401414341fb..061dd84d09f3 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -128,14 +128,16 @@ struct ddebug_class_param { const struct ddebug_class_map *map; }; -#if defined(CONFIG_DYNAMIC_DEBUG_CORE) +/* + * pr_debug() and friends are globally enabled or modules have selectively + * enabled them. + */ +#if defined(CONFIG_DYNAMIC_DEBUG) || \ + (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) extern __printf(2, 3) void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); -extern int ddebug_dyndbg_module_param_cb(char *param, char *val, - const char *modname); - struct device; extern __printf(3, 4) @@ -284,10 +286,6 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, KERN_DEBUG, prefix_str, prefix_type, \ rowsize, groupsize, buf, len, ascii) -struct kernel_param; -int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp); -int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp); - /* for test only, generally expect drm.debug style macro wrappers */ #define __pr_debug_cls(cls, fmt, ...) do { \ BUILD_BUG_ON_MSG(!__builtin_constant_p(cls), \ @@ -295,23 +293,14 @@ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp); dynamic_pr_debug_cls(cls, fmt, ##__VA_ARGS__); \ } while (0) -#else /* !CONFIG_DYNAMIC_DEBUG_CORE */ +#else /* !(CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE)) */ #include #include #include -static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, - const char *modname) -{ - if (!strcmp(param, "dyndbg")) { - /* avoid pr_warn(), which wants pr_fmt() fully defined */ - printk(KERN_WARNING "dyndbg param is supported only in " - "CONFIG_DYNAMIC_DEBUG builds\n"); - return 0; /* allow and ignore */ - } - return -EINVAL; -} +#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) +#define DYNAMIC_DEBUG_BRANCH(descriptor) false #define dynamic_pr_debug(fmt, ...) \ do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0) @@ -324,14 +313,40 @@ static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, rowsize, groupsize, buf, len, ascii); \ } while (0) +#endif /* CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE) */ + + +#ifdef CONFIG_DYNAMIC_DEBUG_CORE + +extern int ddebug_dyndbg_module_param_cb(char *param, char *val, + const char *modname); +struct kernel_param; +int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp); +int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp); + +#else + +static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, + const char *modname) +{ + if (!strcmp(param, "dyndbg")) { + /* avoid pr_warn(), which wants pr_fmt() fully defined */ + printk(KERN_WARNING "dyndbg param is supported only in " + "CONFIG_DYNAMIC_DEBUG builds\n"); + return 0; /* allow and ignore */ + } + return -EINVAL; +} + struct kernel_param; static inline int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) { return 0; } static inline int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) { return 0; } -#endif /* !CONFIG_DYNAMIC_DEBUG_CORE */ +#endif + extern const struct kernel_param_ops param_ops_dyndbg_classes; -#endif +#endif /* _DYNAMIC_DEBUG_H */ diff --git a/lib/Makefile b/lib/Makefile index baf2821f7a00..7afcd85f78f6 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -231,6 +231,9 @@ lib-$(CONFIG_GENERIC_BUG) += bug.o obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o obj-$(CONFIG_DYNAMIC_DEBUG_CORE) += dynamic_debug.o +#ensure exported functions have prototypes +CFLAGS_dynamic_debug.o := -DDYNAMIC_DEBUG_MODULE + obj-$(CONFIG_SYMBOLIC_ERRNAME) += errname.o obj-$(CONFIG_NLATTR) += nlattr.o -- cgit v1.2.3-70-g09d2