linux/tools/perf/util/probe-finder.h
Masami Hiramatsu 221d061182 perf probe: Fix to search local variables in appropriate scope
Fix perf probe to search local variables in appropriate local inlined
function scope. For example, pre_schedule() has only 2 local variables,
as below;

$ perf probe -L pre_schedule
<pre_schedule@/home/mhiramat/ksrc/linux-2.6/kernel/sched.c:0>
      0  static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
         {
      2         if (prev->sched_class->pre_schedule)
      3                 prev->sched_class->pre_schedule(rq, prev);
         }

However, current perf probe shows 4 local variables on pre_schedule(),
because it searches variables in the caller(schedule()) scope.

$ perf probe -V pre_schedule
Available variables at pre_schedule
        @<schedule+445>
                int     cpu
                long unsigned int*      switch_count
                struct rq*      rq
                struct task_struct*     prev

This patch fixes this issue by searching variables in the local scope of
the instance of inlined function. Here is the result.

$ perf probe -V pre_schedule
Available variables at pre_schedule
        @<schedule+445>
                struct rq*      rq
                struct task_struct*     prev

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20110811110259.19900.85664.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-12 09:28:45 -03:00

109 lines
3.0 KiB
C

#ifndef _PROBE_FINDER_H
#define _PROBE_FINDER_H
#include <stdbool.h>
#include "util.h"
#include "probe-event.h"
#define MAX_PATH_LEN 256
#define MAX_PROBE_BUFFER 1024
#define MAX_PROBES 128
static inline int is_c_varname(const char *name)
{
/* TODO */
return isalpha(name[0]) || name[0] == '_';
}
#ifdef DWARF_SUPPORT
#include "dwarf-aux.h"
/* TODO: export debuginfo data structure even if no dwarf support */
/* debug information structure */
struct debuginfo {
Dwarf *dbg;
Dwfl *dwfl;
Dwarf_Addr bias;
};
extern struct debuginfo *debuginfo__new(const char *path);
extern struct debuginfo *debuginfo__new_online_kernel(unsigned long addr);
extern void debuginfo__delete(struct debuginfo *self);
/* Find probe_trace_events specified by perf_probe_event from debuginfo */
extern int debuginfo__find_trace_events(struct debuginfo *self,
struct perf_probe_event *pev,
struct probe_trace_event **tevs,
int max_tevs);
/* Find a perf_probe_point from debuginfo */
extern int debuginfo__find_probe_point(struct debuginfo *self,
unsigned long addr,
struct perf_probe_point *ppt);
/* Find a line range */
extern int debuginfo__find_line_range(struct debuginfo *self,
struct line_range *lr);
/* Find available variables */
extern int debuginfo__find_available_vars_at(struct debuginfo *self,
struct perf_probe_event *pev,
struct variable_list **vls,
int max_points, bool externs);
struct probe_finder {
struct perf_probe_event *pev; /* Target probe event */
/* Callback when a probe point is found */
int (*callback)(Dwarf_Die *sc_die, struct probe_finder *pf);
/* For function searching */
int lno; /* Line number */
Dwarf_Addr addr; /* Address */
const char *fname; /* Real file name */
Dwarf_Die cu_die; /* Current CU */
Dwarf_Die sp_die;
struct list_head lcache; /* Line cache for lazy match */
/* For variable searching */
#if _ELFUTILS_PREREQ(0, 142)
Dwarf_CFI *cfi; /* Call Frame Information */
#endif
Dwarf_Op *fb_ops; /* Frame base attribute */
struct perf_probe_arg *pvar; /* Current target variable */
struct probe_trace_arg *tvar; /* Current result variable */
};
struct trace_event_finder {
struct probe_finder pf;
struct probe_trace_event *tevs; /* Found trace events */
int ntevs; /* Number of trace events */
int max_tevs; /* Max number of trace events */
};
struct available_var_finder {
struct probe_finder pf;
struct variable_list *vls; /* Found variable lists */
int nvls; /* Number of variable lists */
int max_vls; /* Max no. of variable lists */
bool externs; /* Find external vars too */
bool child; /* Search child scopes */
};
struct line_finder {
struct line_range *lr; /* Target line range */
const char *fname; /* File name */
int lno_s; /* Start line number */
int lno_e; /* End line number */
Dwarf_Die cu_die; /* Current CU */
Dwarf_Die sp_die;
int found;
};
#endif /* DWARF_SUPPORT */
#endif /*_PROBE_FINDER_H */