linux/include/trace/events/module.h
Linus Torvalds f322e26238 This contains two fixes.
The first is a long standing bug that causes bogus data to show up
 in the refcnt field of the module_refcnt tracepoint. It was
 introduced by a merge conflict resolution back in 2.6.35-rc days.
 
 The result should be refcnt = incs - decs, but instead it did
 refcnt = incs + decs.
 
 The second fix is to a bug that was introduced in this merge window
 that allowed for a tracepoint funcs pointer to be used after it
 was freed. Moving the location of where the probes are released
 solved the problem.
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Merge tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This contains two fixes.

  The first is a long standing bug that causes bogus data to show up in
  the refcnt field of the module_refcnt tracepoint.  It was introduced
  by a merge conflict resolution back in 2.6.35-rc days.

  The result should be 'refcnt = incs - decs', but instead it did
  'refcnt = incs + decs'.

  The second fix is to a bug that was introduced in this merge window
  that allowed for a tracepoint funcs pointer to be used after it was
  freed.  Moving the location of where the probes are released solved
  the problem"

* tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracepoint: Fix use of tracepoint funcs after rcu free
  trace: module: Maintain a valid user count
2014-05-08 14:17:13 -07:00

134 lines
2.8 KiB
C

/*
* Because linux/module.h has tracepoints in the header, and ftrace.h
* used to include this file, define_trace.h includes linux/module.h
* But we do not want the module.h to override the TRACE_SYSTEM macro
* variable that define_trace.h is processing, so we only set it
* when module events are being processed, which would happen when
* CREATE_TRACE_POINTS is defined.
*/
#ifdef CREATE_TRACE_POINTS
#undef TRACE_SYSTEM
#define TRACE_SYSTEM module
#endif
#if !defined(_TRACE_MODULE_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_MODULE_H
#include <linux/tracepoint.h>
#ifdef CONFIG_MODULES
struct module;
#define show_module_flags(flags) __print_flags(flags, "", \
{ (1UL << TAINT_PROPRIETARY_MODULE), "P" }, \
{ (1UL << TAINT_OOT_MODULE), "O" }, \
{ (1UL << TAINT_FORCED_MODULE), "F" }, \
{ (1UL << TAINT_CRAP), "C" }, \
{ (1UL << TAINT_UNSIGNED_MODULE), "E" })
TRACE_EVENT(module_load,
TP_PROTO(struct module *mod),
TP_ARGS(mod),
TP_STRUCT__entry(
__field( unsigned int, taints )
__string( name, mod->name )
),
TP_fast_assign(
__entry->taints = mod->taints;
__assign_str(name, mod->name);
),
TP_printk("%s %s", __get_str(name), show_module_flags(__entry->taints))
);
TRACE_EVENT(module_free,
TP_PROTO(struct module *mod),
TP_ARGS(mod),
TP_STRUCT__entry(
__string( name, mod->name )
),
TP_fast_assign(
__assign_str(name, mod->name);
),
TP_printk("%s", __get_str(name))
);
#ifdef CONFIG_MODULE_UNLOAD
/* trace_module_get/put are only used if CONFIG_MODULE_UNLOAD is defined */
DECLARE_EVENT_CLASS(module_refcnt,
TP_PROTO(struct module *mod, unsigned long ip),
TP_ARGS(mod, ip),
TP_STRUCT__entry(
__field( unsigned long, ip )
__field( int, refcnt )
__string( name, mod->name )
),
TP_fast_assign(
__entry->ip = ip;
__entry->refcnt = __this_cpu_read(mod->refptr->incs) - __this_cpu_read(mod->refptr->decs);
__assign_str(name, mod->name);
),
TP_printk("%s call_site=%pf refcnt=%d",
__get_str(name), (void *)__entry->ip, __entry->refcnt)
);
DEFINE_EVENT(module_refcnt, module_get,
TP_PROTO(struct module *mod, unsigned long ip),
TP_ARGS(mod, ip)
);
DEFINE_EVENT(module_refcnt, module_put,
TP_PROTO(struct module *mod, unsigned long ip),
TP_ARGS(mod, ip)
);
#endif /* CONFIG_MODULE_UNLOAD */
TRACE_EVENT(module_request,
TP_PROTO(char *name, bool wait, unsigned long ip),
TP_ARGS(name, wait, ip),
TP_STRUCT__entry(
__field( unsigned long, ip )
__field( bool, wait )
__string( name, name )
),
TP_fast_assign(
__entry->ip = ip;
__entry->wait = wait;
__assign_str(name, name);
),
TP_printk("%s wait=%d call_site=%pf",
__get_str(name), (int)__entry->wait, (void *)__entry->ip)
);
#endif /* CONFIG_MODULES */
#endif /* _TRACE_MODULE_H */
/* This part must be outside protection */
#include <trace/define_trace.h>