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 CA28C1CABB; Tue, 25 Jun 2024 05:29:05 +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=1719293345; cv=none; b=Ig5y5h9gvjzS83C9ufMsYc14UihpL2ZYlwLLjpYk7nHEoAzcEvhUeogtfT8HEZJygztvU/sIN/kZq13wvPYYt8EeAq7uF5d9zVluhS+AW9uQSvvDvHn0dY3+hRRh87hdbMXKFeg0z/Q6LhKljZ1XzXgdj/BPMprwzfSheaejHr8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719293345; c=relaxed/simple; bh=LFjHwemcdLE3RjWfSMOIzmFSkp1A8AtvyedlXK7t8pw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QflbRNvDdvuszMavZwaVykpS3BgOKj8/y8MDgIbW3v16lyFQfAz2GPn7kzXPnRAM04J3byMp4NUPVgh+Pi2ZeKVbFHiIOYDjk6VFl1ds6BmRb/IxemT7mJWuoAcYSknUcVfWzPRGyo9/slXp0wsbNF2rXF3xquX69PqmXc6H5tQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WFOh9e1U; 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="WFOh9e1U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDF01C32782; Tue, 25 Jun 2024 05:29:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719293345; bh=LFjHwemcdLE3RjWfSMOIzmFSkp1A8AtvyedlXK7t8pw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WFOh9e1UamzVzR7qSL/yChRjYlxaBXB6f8W5q8tw8hoYeS29+3rL/a+apGHJSHDzE 2OcUL8Dw0boWrZUGYX9s9lEg5VMWD0Z6BAqUgqiKhAn9h+lBo2DiGjZXdxjs9phJIm A9llAwF0m0nErvkjo60MNHszvFkkuY45WeJ+GER84SvY3fUgmsxIp+KUU5+PuR6wwt 28lcLCCZh/9Grkq4O5iCvQFv5RDTuVSDDKP3rbYVOklJblkCrxLON5Otcrvbv54c5+ NlkSixGGSqRWzZT7NkT7rfljL2hABX5T/V0EYe4qhukBYW8XpViUQKR5C9Ym+FV4NM WDV/GSEdzo+gg== Date: Mon, 24 Jun 2024 22:29:03 -0700 From: Namhyung Kim To: Athira Rajeev Cc: acme@kernel.org, jolsa@kernel.org, adrian.hunter@intel.com, irogers@google.com, segher@kernel.crashing.org, christophe.leroy@csgroup.eu, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, akanksha@linux.ibm.com, maddy@linux.ibm.com, kjain@linux.ibm.com, disgoel@linux.vnet.ibm.com Subject: Re: [V4 03/16] tools/perf: Add support to capture and parse raw instruction in powerpc using dso__data_read_offset utility Message-ID: References: <20240614172631.56803-1-atrajeev@linux.vnet.ibm.com> <20240614172631.56803-4-atrajeev@linux.vnet.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20240614172631.56803-4-atrajeev@linux.vnet.ibm.com> On Fri, Jun 14, 2024 at 10:56:18PM +0530, Athira Rajeev wrote: > Add support to capture and parse raw instruction in powerpc. > Currently, the perf tool infrastructure uses two ways to disassemble > and understand the instruction. One is objdump and other option is > via libcapstone. > > Currently, the perf tool infrastructure uses "--no-show-raw-insn" option > with "objdump" while disassemble. Example from powerpc with this option > for an instruction address is: > > Snippet from: > objdump --start-address=
--stop-address=
-d --no-show-raw-insn -C > > c0000000010224b4: lwz r10,0(r9) What about removing --no-show-raw-insn and parse the raw byte code in the output for powerpc? I think it's better to support normal annotation together. > > This line "lwz r10,0(r9)" is parsed to extract instruction name, > registers names and offset. Also to find whether there is a memory > reference in the operands, "memory_ref_char" field of objdump is used. > For x86, "(" is used as memory_ref_char to tackle instructions of the > form "mov (%rax), %rcx". > > In case of powerpc, not all instructions using "(" are the only memory > instructions. Example, above instruction can also be of extended form (X > form) "lwzx r10,0,r19". Inorder to easy identify the instruction category > and extract the source/target registers, patch adds support to use raw > instruction for powerpc. Approach used is to read the raw instruction > directly from the DSO file using "dso__data_read_offset" utility which > is already implemented in perf infrastructure in "util/dso.c". > > Example: > > 38 01 81 e8 ld r4,312(r1) > > Here "38 01 81 e8" is the raw instruction representation. In powerpc, > this translates to instruction form: "ld RT,DS(RA)" and binary code > as: > > | 58 | RT | RA | DS | | > ------------------------------------- > 0 6 11 16 30 31 > > Function "symbol__disassemble_dso" is updated to read raw instruction > directly from DSO using dso__data_read_offset utility. In case of > above example, this captures: > line: 38 01 81 e8 > > Signed-off-by: Athira Rajeev > --- > tools/perf/util/disasm.c | 98 ++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 98 insertions(+) > > diff --git a/tools/perf/util/disasm.c b/tools/perf/util/disasm.c > index b5fe3a7508bb..f19496133bf0 100644 > --- a/tools/perf/util/disasm.c > +++ b/tools/perf/util/disasm.c > @@ -1586,6 +1586,91 @@ static int symbol__disassemble_capstone(char *filename, struct symbol *sym, > } > #endif > > +static int symbol__disassemble_dso(char *filename, struct symbol *sym, Maybe rename to symbol__disassemble_raw() ? > + struct annotate_args *args) > +{ > + struct annotation *notes = symbol__annotation(sym); > + struct map *map = args->ms.map; > + struct dso *dso = map__dso(map); > + u64 start = map__rip_2objdump(map, sym->start); > + u64 end = map__rip_2objdump(map, sym->end); > + u64 len = end - start; > + u64 offset; > + int i, count; > + u8 *buf = NULL; > + char disasm_buf[512]; > + struct disasm_line *dl; > + u32 *line; > + > + /* Return if objdump is specified explicitly */ > + if (args->options->objdump_path) > + return -1; > + > + pr_debug("Reading raw instruction from : %s using dso__data_read_offset\n", filename); You may want to print the actual offset and remove the "using dso__data_read_offset" part. Thanks, Namhyung > + > + buf = malloc(len); > + if (buf == NULL) > + goto err; > + > + count = dso__data_read_offset(dso, NULL, sym->start, buf, len); > + > + line = (u32 *)buf; > + > + if ((u64)count != len) > + goto err; > + > + /* add the function address and name */ > + scnprintf(disasm_buf, sizeof(disasm_buf), "%#"PRIx64" <%s>:", > + start, sym->name); > + > + args->offset = -1; > + args->line = disasm_buf; > + args->line_nr = 0; > + args->fileloc = NULL; > + args->ms.sym = sym; > + > + dl = disasm_line__new(args); > + if (dl == NULL) > + goto err; > + > + annotation_line__add(&dl->al, ¬es->src->source); > + > + /* Each raw instruction is 4 byte */ > + count = len/4; > + > + for (i = 0, offset = 0; i < count; i++) { > + args->offset = offset; > + sprintf(args->line, "%x", line[i]); > + dl = disasm_line__new(args); > + if (dl == NULL) > + goto err; > + > + annotation_line__add(&dl->al, ¬es->src->source); > + offset += 4; > + } > + > + /* It failed in the middle */ > + if (offset != len) { > + struct list_head *list = ¬es->src->source; > + > + /* Discard all lines and fallback to objdump */ > + while (!list_empty(list)) { > + dl = list_first_entry(list, struct disasm_line, al.node); > + > + list_del_init(&dl->al.node); > + disasm_line__free(dl); > + } > + count = -1; > + } > + > +out: > + free(buf); > + return count < 0 ? count : 0; > + > +err: > + count = -1; > + goto out; > +} > /* > * Possibly create a new version of line with tabs expanded. Returns the > * existing or new line, storage is updated if a new line is allocated. If > @@ -1710,6 +1795,19 @@ int symbol__disassemble(struct symbol *sym, struct annotate_args *args) > strcpy(symfs_filename, tmp); > } > > + /* > + * For powerpc data type profiling, use the dso__data_read_offset > + * to read raw instruction directly and interpret the binary code > + * to understand instructions and register fields. For sort keys as > + * type and typeoff, disassemble to mnemonic notation is > + * not required in case of powerpc. > + */ > + if (arch__is(args->arch, "powerpc")) { > + err = symbol__disassemble_dso(symfs_filename, sym, args); > + if (err == 0) > + goto out_remove_tmp; > + } > + > #ifdef HAVE_LIBCAPSTONE_SUPPORT > err = symbol__disassemble_capstone(symfs_filename, sym, args); > if (err == 0) > -- > 2.43.0 >