From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EB6048060A; Tue, 19 Mar 2024 13:45:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710855944; cv=none; b=dD6uv4WmrbIUR/98mKp69jH6Dlb98CDzKkvqOr5E+z6BQrjMflB9TXJq1KESqHSvJmrD/lEcTPYRofj7CR5iLCMJwYfRCw3SHjmYXyC2EqZwEq8Lh0lapyxJ8WR6S0ebLIRli3887kLhToOYiz8xvbosutanys4tMPy8P/BEeY4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710855944; c=relaxed/simple; bh=zkpPzHkw72QXh0PXml5o0fAbrp7+GSEBgMu/g08LkEs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZII0Gx54+Unn7aacE5d2oVklGyuZkmS7NRHt8Utw30+8DZQBvz8hRiumJrR/M54SeKKTWtlIQsNwqadifcNH9ykrHamVKduC5OY4xfGafjizBScizxzD2FiTAdc/nc6lfJAZ32KPfIm5XCwkXK/o4KmLJuDUlRC5TeUOTxyFYRM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BvA5Y+dQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BvA5Y+dQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED34EC433C7; Tue, 19 Mar 2024 13:45:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1710855943; bh=zkpPzHkw72QXh0PXml5o0fAbrp7+GSEBgMu/g08LkEs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BvA5Y+dQZv6M6dBJNAN9I+EPj7iONJVKrxd2ODJOx8z1vXg+v9umxAKyczOR9dBgR Q7737GVcT0bppE7yuAxsk015bJ29hUeZJIEiOMV1OkmY5rMp8yWwCsrORqbT/subLZ CmSwIBNNBAuDh24siRwcmIwVUPaDDt1WXvEHXyma49bczRYsJMzalKHb+2KzYN54cn I9uPlzA9pa1XC8sVh1fACYVSZkcAreYAdgnu3yqmmn8EiQsKrnbd5RlM+BSms52m/N DMB6/63kwKWWZ9OgQwpWR0ZIxZjyOjJNnnhYC3/IfND29h3p2q3C/5NttFw1KQLCOQ 8lHbgoSSRW6/g== Date: Tue, 19 Mar 2024 10:45:40 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Ian Rogers , Jiri Olsa , Adrian Hunter , Peter Zijlstra , Ingo Molnar , LKML , linux-perf-users@vger.kernel.org, Linus Torvalds , Stephane Eranian , Masami Hiramatsu , linux-toolchains@vger.kernel.org, linux-trace-devel@vger.kernel.org Subject: Re: [PATCH 02/23] perf dwarf-aux: Add die_collect_vars() Message-ID: References: <20240319055115.4063940-1-namhyung@kernel.org> <20240319055115.4063940-3-namhyung@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240319055115.4063940-3-namhyung@kernel.org> On Mon, Mar 18, 2024 at 10:50:54PM -0700, Namhyung Kim 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). > > Acked-by: Masami Hiramatsu (Google) Acked-by: Arnaldo Carvalho de Melo - Arnaldo > Signed-off-by: Namhyung Kim > --- > tools/perf/util/dwarf-aux.c | 118 +++++++++++++++++++++++++++--------- > tools/perf/util/dwarf-aux.h | 17 ++++++ > 2 files changed, 107 insertions(+), 28 deletions(-) > > diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c > index e84d0d6a7750..785aa7a3d725 100644 > --- a/tools/perf/util/dwarf-aux.c > +++ b/tools/perf/util/dwarf-aux.c > @@ -1136,6 +1136,40 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf) > return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die)); > } > > +#if defined(HAVE_DWARF_GETLOCATIONS_SUPPORT) || defined(HAVE_DWARF_CFI_SUPPORT) > +static int reg_from_dwarf_op(Dwarf_Op *op) > +{ > + switch (op->atom) { > + case DW_OP_reg0 ... DW_OP_reg31: > + return op->atom - DW_OP_reg0; > + case DW_OP_breg0 ... DW_OP_breg31: > + return op->atom - DW_OP_breg0; > + case DW_OP_regx: > + case DW_OP_bregx: > + return op->number; > + default: > + break; > + } > + return -1; > +} > + > +static int offset_from_dwarf_op(Dwarf_Op *op) > +{ > + switch (op->atom) { > + case DW_OP_reg0 ... DW_OP_reg31: > + case DW_OP_regx: > + return 0; > + case DW_OP_breg0 ... DW_OP_breg31: > + return op->number; > + case DW_OP_bregx: > + return op->number2; > + default: > + break; > + } > + return -1; > +} > +#endif /* HAVE_DWARF_GETLOCATIONS_SUPPORT || HAVE_DWARF_CFI_SUPPORT */ > + > #ifdef HAVE_DWARF_GETLOCATIONS_SUPPORT > /** > * die_get_var_innermost_scope - Get innermost scope range of given variable DIE > @@ -1476,41 +1510,69 @@ Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die, Dwarf_Addr addr, > *offset = data.offset; > return result; > } > -#endif /* HAVE_DWARF_GETLOCATIONS_SUPPORT */ > > -#ifdef HAVE_DWARF_CFI_SUPPORT > -static int reg_from_dwarf_op(Dwarf_Op *op) > +static int __die_collect_vars_cb(Dwarf_Die *die_mem, void *arg) > { > - switch (op->atom) { > - case DW_OP_reg0 ... DW_OP_reg31: > - return op->atom - DW_OP_reg0; > - case DW_OP_breg0 ... DW_OP_breg31: > - return op->atom - DW_OP_breg0; > - case DW_OP_regx: > - case DW_OP_bregx: > - return op->number; > - default: > - break; > - } > - return -1; > + 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; > } > > -static int offset_from_dwarf_op(Dwarf_Op *op) > +/** > + * 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) > { > - switch (op->atom) { > - case DW_OP_reg0 ... DW_OP_reg31: > - case DW_OP_regx: > - return 0; > - case DW_OP_breg0 ... DW_OP_breg31: > - return op->number; > - case DW_OP_bregx: > - return op->number2; > - default: > - break; > - } > - return -1; > + Dwarf_Die die_mem; > + > + die_find_child(sc_die, __die_collect_vars_cb, (void *)var_types, &die_mem); > } > +#endif /* HAVE_DWARF_GETLOCATIONS_SUPPORT */ > > +#ifdef HAVE_DWARF_CFI_SUPPORT > /** > * die_get_cfa - Get frame base information > * @dwarf: a Dwarf info > diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h > index 9973801a20c1..cd171b06fd4c 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 */ > @@ -149,6 +158,9 @@ Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die, Dwarf_Addr pc, int reg, > Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die, Dwarf_Addr addr, > Dwarf_Die *die_mem, int *offset); > > +/* 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, > @@ -176,6 +188,11 @@ static inline Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die __maybe_unu > return NULL; > } > > +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 */ > > #ifdef HAVE_DWARF_CFI_SUPPORT > -- > 2.44.0.291.gc1ea87d7ee-goog