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Message-ID: <9d070742-8a82-3cb0-cea0-8ecce01c06b6@huawei.com>
Date:   Fri, 9 Sep 2022 17:40:08 +0800
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Subject: Re: [PATCH 2/2] riscv: tracing: Improve hardirq tracing message
To:     <linux-riscv@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        <rostedt@goodmis.org>, <mingo@redhat.com>,
        <paul.walmsley@sifive.com>, <palmer@dabbelt.com>,
        <aou@eecs.berkeley.edu>
CC:     <liaochang1@huawei.com>, <chris.zjh@huawei.com>
References: <20220901104515.135162-1-zouyipeng@huawei.com>
 <20220901104515.135162-3-zouyipeng@huawei.com>
From:   Yipeng Zou <zouyipeng@huawei.com>
In-Reply-To: <20220901104515.135162-3-zouyipeng@huawei.com>
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Ping.

在 2022/9/1 18:45, Yipeng Zou 写道:
> Use trace_hardirqs_on_caller to improve irq_tracing message.
>
> lockdep log in riscv showing the last {enabled,disabled} at
> __trace_hardirqs_{on,off} all the time(if called by).
> But that's not what we want to see, the caller is what we want.
>
> Before this commit:
> [   57.853175] hardirqs last  enabled at (2519): __trace_hardirqs_on+0xc/0x14
> [   57.853848] hardirqs last disabled at (2520): __trace_hardirqs_off+0xc/0x14
>
> After this commit
> [   53.781428] hardirqs last  enabled at (2595): restore_all+0xe/0x66
> [   53.782185] hardirqs last disabled at (2596): ret_from_exception+0xa/0x10
>
> Signed-off-by: Yipeng Zou <zouyipeng@huawei.com>
> ---
>   arch/riscv/kernel/trace_irq.c | 4 ++--
>   include/linux/irqflags.h      | 2 ++
>   2 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/kernel/trace_irq.c b/arch/riscv/kernel/trace_irq.c
> index 095ac976d7da..7ca24b26e19f 100644
> --- a/arch/riscv/kernel/trace_irq.c
> +++ b/arch/riscv/kernel/trace_irq.c
> @@ -16,12 +16,12 @@
>   
>   void __trace_hardirqs_on(void)
>   {
> -	trace_hardirqs_on();
> +	trace_hardirqs_on_caller(CALLER_ADDR0);
>   }
>   NOKPROBE_SYMBOL(__trace_hardirqs_on);
>   
>   void __trace_hardirqs_off(void)
>   {
> -	trace_hardirqs_off();
> +	trace_hardirqs_off_caller(CALLER_ADDR0);
>   }
>   NOKPROBE_SYMBOL(__trace_hardirqs_off);
> diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
> index 5ec0fa71399e..46774fa85cde 100644
> --- a/include/linux/irqflags.h
> +++ b/include/linux/irqflags.h
> @@ -53,6 +53,8 @@ extern void trace_hardirqs_on_prepare(void);
>   extern void trace_hardirqs_off_finish(void);
>   extern void trace_hardirqs_on(void);
>   extern void trace_hardirqs_off(void);
> +extern void trace_hardirqs_on_caller(unsigned long caller_addr);
> +extern void trace_hardirqs_off_caller(unsigned long caller_addr);
>   
>   # define lockdep_hardirq_context()	(raw_cpu_read(hardirq_context))
>   # define lockdep_softirq_context(p)	((p)->softirq_context)

-- 
Regards,
Yipeng Zou