| Message ID | 20231012035111.676789-35-namhyung@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | perf tools: Introduce data type profiling (v1) | expand |
On Wed, 11 Oct 2023 20:50:57 -0700 Namhyung Kim <namhyung@kernel.org> wrote: > The die_collect_vars() is to find all variable information in the scope > including function parameters. The struct die_var_type is to save the > type of the variable with the location (reg and offset) as well as where > it's defined in the code (addr). > This looks good to me. Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> BTW, I did similar thing in collect_variables_cb()@probe-finder.c, maybe this can simplify that too. Thank you, > Signed-off-by: Namhyung Kim <namhyung@kernel.org> > --- > tools/perf/util/dwarf-aux.c | 60 +++++++++++++++++++++++++++++++++++++ > tools/perf/util/dwarf-aux.h | 17 +++++++++++ > 2 files changed, 77 insertions(+) > > diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c > index 093d7e82b333..16e63d8caf83 100644 > --- a/tools/perf/util/dwarf-aux.c > +++ b/tools/perf/util/dwarf-aux.c > @@ -1545,6 +1545,66 @@ int die_get_cfa(Dwarf *dwarf, u64 pc, int *preg, int *poffset) > return -1; > } > > +static int __die_collect_vars_cb(Dwarf_Die *die_mem, void *arg) > +{ > + struct die_var_type **var_types = arg; > + Dwarf_Die type_die; > + int tag = dwarf_tag(die_mem); > + Dwarf_Attribute attr; > + Dwarf_Addr base, start, end; > + Dwarf_Op *ops; > + size_t nops; > + struct die_var_type *vt; > + > + if (tag != DW_TAG_variable && tag != DW_TAG_formal_parameter) > + return DIE_FIND_CB_SIBLING; > + > + if (dwarf_attr(die_mem, DW_AT_location, &attr) == NULL) > + return DIE_FIND_CB_SIBLING; > + > + /* > + * Only collect the first location as it can reconstruct the > + * remaining state by following the instructions. > + * start = 0 means it covers the whole range. > + */ > + if (dwarf_getlocations(&attr, 0, &base, &start, &end, &ops, &nops) <= 0) > + return DIE_FIND_CB_SIBLING; > + > + if (die_get_real_type(die_mem, &type_die) == NULL) > + return DIE_FIND_CB_SIBLING; > + > + vt = malloc(sizeof(*vt)); > + if (vt == NULL) > + return DIE_FIND_CB_END; > + > + vt->die_off = dwarf_dieoffset(&type_die); > + vt->addr = start; > + vt->reg = reg_from_dwarf_op(ops); > + vt->offset = offset_from_dwarf_op(ops); > + vt->next = *var_types; > + *var_types = vt; > + > + return DIE_FIND_CB_SIBLING; > +} > + > +/** > + * die_collect_vars - Save all variables and parameters > + * @sc_die: a scope DIE > + * @var_types: a pointer to save the resulting list > + * > + * Save all variables and parameters in the @sc_die and save them to @var_types. > + * The @var_types is a singly-linked list containing type and location info. > + * Actual type can be retrieved using dwarf_offdie() with 'die_off' later. > + * > + * Callers should free @var_types. > + */ > +void die_collect_vars(Dwarf_Die *sc_die, struct die_var_type **var_types) > +{ > + Dwarf_Die die_mem; > + > + die_find_child(sc_die, __die_collect_vars_cb, (void *)var_types, &die_mem); > +} > + > #endif > > /* > diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h > index dc7e98678216..d0ef41738abd 100644 > --- a/tools/perf/util/dwarf-aux.h > +++ b/tools/perf/util/dwarf-aux.h > @@ -135,6 +135,15 @@ void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die, > /* Get the list of including scopes */ > int die_get_scopes(Dwarf_Die *cu_die, Dwarf_Addr pc, Dwarf_Die **scopes); > > +/* Variable type information */ > +struct die_var_type { > + struct die_var_type *next; > + u64 die_off; > + u64 addr; > + int reg; > + int offset; > +}; > + > #ifdef HAVE_DWARF_GETLOCATIONS_SUPPORT > > /* Get byte offset range of given variable DIE */ > @@ -153,6 +162,9 @@ Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die, Dwarf_Addr pc, > /* Get the frame base information from CFA */ > int die_get_cfa(Dwarf *dwarf, u64 pc, int *preg, int *poffset); > > +/* Save all variables and parameters in this scope */ > +void die_collect_vars(Dwarf_Die *sc_die, struct die_var_type **var_types); > + > #else /* HAVE_DWARF_GETLOCATIONS_SUPPORT */ > > static inline int die_get_var_range(Dwarf_Die *sp_die __maybe_unused, > @@ -187,6 +199,11 @@ static inline int die_get_cfa(Dwarf *dwarf __maybe_unused, u64 pc __maybe_unused > return -1; > } > > +static inline void die_collect_vars(Dwarf_Die *sc_die __maybe_unused, > + struct die_var_type **var_types __maybe_unused) > +{ > +} > + > #endif /* HAVE_DWARF_GETLOCATIONS_SUPPORT */ > > #endif /* _DWARF_AUX_H */ > -- > 2.42.0.655.g421f12c284-goog >
On Wed, Nov 8, 2023 at 2:52 AM Masami Hiramatsu <mhiramat@kernel.org> wrote: > > On Wed, 11 Oct 2023 20:50:57 -0700 > Namhyung Kim <namhyung@kernel.org> wrote: > > > The die_collect_vars() is to find all variable information in the scope > > including function parameters. The struct die_var_type is to save the > > type of the variable with the location (reg and offset) as well as where > > it's defined in the code (addr). > > > > This looks good to me. > > Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Thanks! > > BTW, I did similar thing in collect_variables_cb()@probe-finder.c, maybe > this can simplify that too. Ok, I'll take a look later. Thanks, Namhyung
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c index 093d7e82b333..16e63d8caf83 100644 --- a/tools/perf/util/dwarf-aux.c +++ b/tools/perf/util/dwarf-aux.c @@ -1545,6 +1545,66 @@ int die_get_cfa(Dwarf *dwarf, u64 pc, int *preg, int *poffset) return -1; } +static int __die_collect_vars_cb(Dwarf_Die *die_mem, void *arg) +{ + struct die_var_type **var_types = arg; + Dwarf_Die type_die; + int tag = dwarf_tag(die_mem); + Dwarf_Attribute attr; + Dwarf_Addr base, start, end; + Dwarf_Op *ops; + size_t nops; + struct die_var_type *vt; + + if (tag != DW_TAG_variable && tag != DW_TAG_formal_parameter) + return DIE_FIND_CB_SIBLING; + + if (dwarf_attr(die_mem, DW_AT_location, &attr) == NULL) + return DIE_FIND_CB_SIBLING; + + /* + * Only collect the first location as it can reconstruct the + * remaining state by following the instructions. + * start = 0 means it covers the whole range. + */ + if (dwarf_getlocations(&attr, 0, &base, &start, &end, &ops, &nops) <= 0) + return DIE_FIND_CB_SIBLING; + + if (die_get_real_type(die_mem, &type_die) == NULL) + return DIE_FIND_CB_SIBLING; + + vt = malloc(sizeof(*vt)); + if (vt == NULL) + return DIE_FIND_CB_END; + + vt->die_off = dwarf_dieoffset(&type_die); + vt->addr = start; + vt->reg = reg_from_dwarf_op(ops); + vt->offset = offset_from_dwarf_op(ops); + vt->next = *var_types; + *var_types = vt; + + return DIE_FIND_CB_SIBLING; +} + +/** + * die_collect_vars - Save all variables and parameters + * @sc_die: a scope DIE + * @var_types: a pointer to save the resulting list + * + * Save all variables and parameters in the @sc_die and save them to @var_types. + * The @var_types is a singly-linked list containing type and location info. + * Actual type can be retrieved using dwarf_offdie() with 'die_off' later. + * + * Callers should free @var_types. + */ +void die_collect_vars(Dwarf_Die *sc_die, struct die_var_type **var_types) +{ + Dwarf_Die die_mem; + + die_find_child(sc_die, __die_collect_vars_cb, (void *)var_types, &die_mem); +} + #endif /* diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h index dc7e98678216..d0ef41738abd 100644 --- a/tools/perf/util/dwarf-aux.h +++ b/tools/perf/util/dwarf-aux.h @@ -135,6 +135,15 @@ void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die, /* Get the list of including scopes */ int die_get_scopes(Dwarf_Die *cu_die, Dwarf_Addr pc, Dwarf_Die **scopes); +/* Variable type information */ +struct die_var_type { + struct die_var_type *next; + u64 die_off; + u64 addr; + int reg; + int offset; +}; + #ifdef HAVE_DWARF_GETLOCATIONS_SUPPORT /* Get byte offset range of given variable DIE */ @@ -153,6 +162,9 @@ Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die, Dwarf_Addr pc, /* Get the frame base information from CFA */ int die_get_cfa(Dwarf *dwarf, u64 pc, int *preg, int *poffset); +/* Save all variables and parameters in this scope */ +void die_collect_vars(Dwarf_Die *sc_die, struct die_var_type **var_types); + #else /* HAVE_DWARF_GETLOCATIONS_SUPPORT */ static inline int die_get_var_range(Dwarf_Die *sp_die __maybe_unused, @@ -187,6 +199,11 @@ static inline int die_get_cfa(Dwarf *dwarf __maybe_unused, u64 pc __maybe_unused return -1; } +static inline void die_collect_vars(Dwarf_Die *sc_die __maybe_unused, + struct die_var_type **var_types __maybe_unused) +{ +} + #endif /* HAVE_DWARF_GETLOCATIONS_SUPPORT */ #endif /* _DWARF_AUX_H */
The die_collect_vars() is to find all variable information in the scope including function parameters. The struct die_var_type is to save the type of the variable with the location (reg and offset) as well as where it's defined in the code (addr). Signed-off-by: Namhyung Kim <namhyung@kernel.org> --- tools/perf/util/dwarf-aux.c | 60 +++++++++++++++++++++++++++++++++++++ tools/perf/util/dwarf-aux.h | 17 +++++++++++ 2 files changed, 77 insertions(+)