From: Qi Liu <liuqi115@huawei.com>
To: <catalin.marinas@arm.com>, <will@kernel.org>,
<naveen.n.rao@linux.ibm.com>, <anil.s.keshavamurthy@intel.com>,
<davem@davemloft.net>, <mhiramat@kernel.org>,
<linux-arm-kernel@lists.infradead.org>
Cc: <song.bao.hua@hisilicon.com>, <prime.zeng@hisilicon.com>,
<robin.murphy@arm.com>, <f.fangjian@huawei.com>,
<liuqi115@huawei.com>, <linuxarm@huawei.com>,
<linux-kernel@vger.kernel.org>
Subject: [PATCH v4 0/2] arm64: Enable OPTPROBE for arm64
Date: Wed, 18 Aug 2021 15:33:34 +0800 [thread overview]
Message-ID: <20210818073336.59678-1-liuqi115@huawei.com> (raw)
This patch introduce optprobe for ARM64, using a branch instruction
to replace probed instruction.
The test result on Hip08 platform is shown here, and optprobe could
reduce the latency to 1/4 of normal kprobe
kprobe before optimized:
[280709.846380] do_empty returned 0 and took 1530 ns to execute
[280709.852057] do_empty returned 0 and took 550 ns to execute
[280709.857631] do_empty returned 0 and took 440 ns to execute
[280709.863215] do_empty returned 0 and took 380 ns to execute
[280709.868787] do_empty returned 0 and took 360 ns to execute
[280709.874362] do_empty returned 0 and took 340 ns to execute
[280709.879936] do_empty returned 0 and took 320 ns to execute
[280709.885505] do_empty returned 0 and took 300 ns to execute
[280709.891075] do_empty returned 0 and took 280 ns to execute
[280709.896646] do_empty returned 0 and took 290 ns to execute
[280709.902220] do_empty returned 0 and took 290 ns to execute
[280709.907807] do_empty returned 0 and took 290 ns to execute
optprobe:
[ 2965.964572] do_empty returned 0 and took 90 ns to execute
[ 2965.969952] do_empty returned 0 and took 80 ns to execute
[ 2965.975332] do_empty returned 0 and took 70 ns to execute
[ 2965.980714] do_empty returned 0 and took 60 ns to execute
[ 2965.986128] do_empty returned 0 and took 80 ns to execute
[ 2965.991507] do_empty returned 0 and took 70 ns to execute
[ 2965.996884] do_empty returned 0 and took 70 ns to execute
[ 2966.002262] do_empty returned 0 and took 80 ns to execute
[ 2966.007642] do_empty returned 0 and took 70 ns to execute
[ 2966.013020] do_empty returned 0 and took 70 ns to execute
[ 2966.018400] do_empty returned 0 and took 70 ns to execute
[ 2966.023779] do_empty returned 0 and took 70 ns to execute
[ 2966.029158] do_empty returned 0 and took 70 ns to execute
Changes since V3:
- Address the comments from Masami, reduce the number of aarch64_insn_patch_text
in arch_optimize_kprobes() and arch_unoptimize_kprobes().
- Link: https://lore.kernel.org/lkml/20210810055330.18924-1-liuqi115@huawei.com/
Changes since V2:
- Address the comments from Masami, prepare another writable buffer in
arch_prepare_optimized_kprobe()and build the trampoline code on it.
- Address the comments from Amit, move save_all_base_regs and
restore_all_base_regs to <asm/assembler.h>, as these two macros are reused
in optprobe.
- Link: https://lore.kernel.org/lkml/20210804060209.95817-1-liuqi115@huawei.com/
Changes since V1:
- Address the comments from Masami, checks for all branch instructions, and
use aarch64_insn_patch_text_nosync() instead of aarch64_insn_patch_text()
in each probe.
- Link: https://lore.kernel.org/lkml/20210719122417.10355-1-liuqi115@huawei.com/
Qi Liu (2):
Make save_all_base_regs and restore_all_base_regs as common macro
arm64: kprobe: Enable OPTPROBE for arm64
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/assembler.h | 52 ++++
arch/arm64/include/asm/kprobes.h | 24 ++
arch/arm64/kernel/probes/Makefile | 2 +
arch/arm64/kernel/probes/kprobes.c | 19 +-
arch/arm64/kernel/probes/kprobes_trampoline.S | 52 ----
arch/arm64/kernel/probes/opt_arm64.c | 276 ++++++++++++++++++
.../arm64/kernel/probes/optprobe_trampoline.S | 37 +++
8 files changed, 408 insertions(+), 55 deletions(-)
create mode 100644 arch/arm64/kernel/probes/opt_arm64.c
create mode 100644 arch/arm64/kernel/probes/optprobe_trampoline.S
--
2.17.1
next reply other threads:[~2021-08-18 10:57 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-18 7:33 Qi Liu [this message]
2021-08-18 7:33 ` [PATCH v4 1/2] Make save_all_base_regs and restore_all_base_regs as common macro Qi Liu
2021-08-18 7:33 ` [PATCH v4 2/2] arm64: kprobe: Enable OPTPROBE for arm64 Qi Liu
2021-08-18 16:27 ` Masami Hiramatsu
2021-08-24 10:50 ` Mark Rutland
2021-08-24 11:50 ` Barry Song
2021-08-24 12:11 ` Mark Rutland
2021-08-24 12:42 ` Barry Song
2021-08-25 2:13 ` Masami Hiramatsu
2021-08-25 3:12 ` Barry Song
2021-09-07 3:14 ` liuqi (BA)
2021-11-26 10:31 ` liuqi (BA)
2021-11-27 12:23 ` Masami Hiramatsu
2021-11-29 1:40 ` liuqi (BA)
2021-11-29 5:00 ` Masami Hiramatsu
2021-11-29 6:50 ` liuqi (BA)
2021-11-29 14:35 ` Masami Hiramatsu
2021-11-30 6:48 ` liuqi (BA)
2021-12-01 1:50 ` Masami Hiramatsu
2021-12-01 2:55 ` liuqi (BA)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210818073336.59678-1-liuqi115@huawei.com \
--to=liuqi115@huawei.com \
--cc=anil.s.keshavamurthy@intel.com \
--cc=catalin.marinas@arm.com \
--cc=davem@davemloft.net \
--cc=f.fangjian@huawei.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxarm@huawei.com \
--cc=mhiramat@kernel.org \
--cc=naveen.n.rao@linux.ibm.com \
--cc=prime.zeng@hisilicon.com \
--cc=robin.murphy@arm.com \
--cc=song.bao.hua@hisilicon.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).