linux/lib/dynamic_debug.c, branch v3.6-rc1

Revert "dynamic_debug: remove unneeded includes"

2012-05-07T23:47:32Z

This reverts commit 04db6e5fddca55186b6a74339a62c800150648bc. Odds are, we really don't want to revert all of these, and need to be more careful in the future to make sure we don't break the build of other arches. Reported-by: Stephen Rothwell Cc: Jim Cromie Signed-off-by: Greg Kroah-Hartman

dynamic_debug: remove unneeded includes

2012-05-05T00:25:46Z

These arent currently needed, so drop them. Some will probably get re-added when static-branches are added, but include loops prevent that at present. Signed-off-by: Jim Cromie Signed-off-by: Greg Kroah-Hartman

dynamic_debug: init with early_initcall, not arch_initcall

2012-04-30T20:26:31Z

1- Call dynamic_debug_init() from early_initcall, not arch_initcall. 2- Call dynamic_debug_init_debugfs() from fs_initcall, not module_init. RFC: This works for me on a 64 bit desktop and a i586 SBC, but is untested on other arches. I presume there is or was a reason original code used arch_initcall, maybe the constraints have changed. This makes facility available as soon as possible. 2nd change has a downside when dynamic_debug.verbose=1; all the vpr_info()s called in the proc-fs code are activated, causing voluminous output from dmesg. TBD: Im unsure of this explanation, but the output is there. This could be fixed by changing those callsites to v2pr_info(if verbose > 1). 1st change is still not early enough to enable pr_debugs in kernel/params, so parsing of boot-args isnt logged. The reparse of those args is however visible after params.dyndbg="+p" is processed. Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: add modname arg to exec_query callchain

2012-04-30T20:25:39Z

Pass module name into ddebug_exec_queries(), ddebug_exec_query(), and ddebug_parse_query() as separate parameter. In ddebug_parse_query(), the module name is added into the query struct before the query-string is parsed. This allows the query-string to be shorter: instead of: $modname.dyndbg="module $modname +fp" do this: $modname.dyndbg="+fp" Omitting "module $modname" from the query string is actually required for $modname.dyndbg rules; the set-only-once check added in a previous patch will throw an error if its added again. ddebug_query="..." has no $modname associated with it, so the query string may include it. This also fixes redundant "module $modname" otherwise needed to handle multiple queries per string: $modname.dyndbg="func foo +fp; func bar +fp" Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: print ram usage by ddebug tables if verbose

2012-04-30T20:25:39Z

Print ram usage of dynamic-debug tables and verbose section so user knows cost of enabling CONFIG_DYNAMIC_DEBUG. This only counts the size of the _ddebug tables for builtins and the __verbose section that they refer to, not those used in loadable modules. Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: simplify dynamic_debug_init error exit

2012-04-30T20:25:39Z

We dont want errors while parsing ddebug_query to unload ddebug tables, so set success after tables are loaded, and return 0 after query parsing is done. Simplify error handling code since its no longer used for success, and change goto label to out_err to clarify this. Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: combine parse_args callbacks together

2012-04-30T20:24:34Z

Refactor ddebug_dyndbg_boot_param_cb and ddebug_dyndbg_module_param_cb into a common helper function, and call it from both. The handling of foo.dyndbg is unneeded by the latter, but harmless. The 2 callers differ only by pr_info and the return code they pass to the helper for when an unknown param is handled. I could slightly reduce dmesg clutter by putting the vpr_info in the common helper, after the return on_err, but that loses __func__ context, is overly silent on module_cb unknown param errors, and the clutter is only when dynamic_debug.verbose=1 anyway. Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: deprecate ddebug_query, suggest dyndbg instead

2012-04-30T20:24:34Z

With ddebug_dyndbg_boot_params_cb() handling bare dyndbg params, we dont need ddebug_query param anymore. Add a warning when processing ddebug_query= param that it is deprecated, and to change it to dyndbg= Add a deprecation notice for v3.8 to feature-removal-schedule.txt, and add a suggested deprecation period of 3 releases to the header. Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: make dynamic-debug work for module initialization

2012-04-30T18:31:46Z

This introduces a fake module param $module.dyndbg. Its based upon Thomas Renninger's $module.ddebug boot-time debugging patch from https://lkml.org/lkml/2010/9/15/397 The 'fake' module parameter is provided for all modules, whether or not they need it. It is not explicitly added to each module, but is implemented in callbacks invoked from parse_args. For builtin modules, dynamic_debug_init() now directly calls parse_args(..., &ddebug_dyndbg_boot_params_cb), to process the params undeclared in the modules, just after the ddebug tables are processed. While its slightly weird to reprocess the boot params, parse_args() is already called repeatedly by do_initcall_levels(). More importantly, the dyndbg queries (given in ddebug_query or dyndbg params) cannot be activated until after the ddebug tables are ready, and reusing parse_args is cleaner than doing an ad-hoc parse. This reparse would break options like inc_verbosity, but they probably should be params, like verbosity=3. ddebug_dyndbg_boot_params_cb() handles both bare dyndbg (aka: ddebug_query) and module-prefixed dyndbg params, and ignores all other parameters. For example, the following will enable pr_debug()s in 4 builtin modules, in the order given: dyndbg="module params +p; module aio +p" module.dyndbg=+p pci.dyndbg For loadable modules, parse_args() in load_module() calls ddebug_dyndbg_module_params_cb(). This handles bare dyndbg params as passed from modprobe, and errors on other unknown params. Note that modprobe reads /proc/cmdline, so "modprobe foo" grabs all foo.params, strips the "foo.", and passes these to the kernel. ddebug_dyndbg_module_params_cb() is again called for the unknown params; it handles dyndbg, and errors on others. The "doing" arg added previously contains the module name. For non CONFIG_DYNAMIC_DEBUG builds, the stub function accepts and ignores $module.dyndbg params, other unknowns get -ENOENT. If no param value is given (as in pci.dyndbg example above), "+p" is assumed, which enables all pr_debug callsites in the module. The dyndbg fake parameter is not shown in /sys/module/*/parameters, thus it does not use any resources. Changes to it are made via the control file. Also change pr_info in ddebug_exec_queries to vpr_info, no need to see it all the time. Signed-off-by: Jim Cromie CC: Thomas Renninger CC: Rusty Russell Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman

dynamic_debug: replace if (verbose) pr_info with macro vpr_info

2012-04-30T17:35:30Z

Use vpr_info to declutter code, reduce indenting, and change one additional pr_info call in ddebug_exec_queries. Signed-off-by: Jim Cromie Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman