From: Liao Chang <liaochang1@huawei.com>
To: <catalin.marinas@arm.com>, <will@kernel.org>, <guoren@kernel.org>,
<paul.walmsley@sifive.com>, <palmer@dabbelt.com>,
<aou@eecs.berkeley.edu>, <rostedt@goodmis.org>,
<mhiramat@kernel.org>, <liaochang1@huawei.com>, <maz@kernel.org>,
<alexandru.elisei@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>, <linux-csky@vger.kernel.org>,
<linux-riscv@lists.infradead.org>
Subject: [PATCH V2 3/3] arm64/kprobe: Optimize the performance of patching single-step slot
Date: Tue, 13 Sep 2022 11:34:54 +0800 [thread overview]
Message-ID: <20220913033454.104519-4-liaochang1@huawei.com> (raw)
In-Reply-To: <20220913033454.104519-1-liaochang1@huawei.com>
Single-step slot would not be used until kprobe is enabled, that means
no race condition occurs on it under SMP, hence it is safe to pacth ss
slot without stopping machine.
Signed-off-by: Liao Chang <liaochang1@huawei.com>
---
arch/arm64/kernel/probes/kprobes.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index d1d182320245..5902e33fd3b6 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -44,11 +44,10 @@ post_kprobe_handler(struct kprobe *, struct kprobe_ctlblk *, struct pt_regs *);
static void __kprobes arch_prepare_ss_slot(struct kprobe *p)
{
kprobe_opcode_t *addr = p->ainsn.api.insn;
- void *addrs[] = {addr, addr + 1};
- u32 insns[] = {p->opcode, BRK64_OPCODE_KPROBES_SS};
/* prepare insn slot */
- aarch64_insn_patch_text(addrs, insns, 2);
+ aarch64_insn_write(addr, p->opcode);
+ aarch64_insn_write(addr + 1, BRK64_OPCODE_KPROBES_SS);
flush_icache_range((uintptr_t)addr, (uintptr_t)(addr + MAX_INSN_SIZE));
--
2.17.1
next prev parent reply other threads:[~2022-09-13 3:38 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-13 3:34 [PATCH V2 0/3] kprobe: Optimize the performance of patching ss Liao Chang
2022-09-13 3:34 ` [PATCH V2 1/3] riscv/kprobe: Optimize the performance of patching single-step slot Liao Chang
2022-09-13 3:34 ` [PATCH V2 2/3] csky/kprobe: " Liao Chang
2022-09-13 3:34 ` Liao Chang [this message]
2022-09-22 13:38 ` [PATCH V2 3/3] arm64/kprobe: " Will Deacon
2022-09-23 1:24 ` liaochang (A)
2022-09-13 11:19 ` [PATCH V2 0/3] kprobe: Optimize the performance of patching ss Masami Hiramatsu
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