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Message-ID: <c2b8abb2-3a1e-6c49-6d3d-d8b29232e41b@huawei.com>
Date:   Tue, 4 Apr 2023 10:03:33 +0800
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Subject: Re: [PATCH] x86: profiling: Using generic unwinding in profile_pc
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To:     Andi Kleen <ak@linux.intel.com>, "x86@kernel.org" <x86@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
CC:     "tglx@linutronix.de" <tglx@linutronix.de>,
        "mingo@redhat.com" <mingo@redhat.com>,
        "bp@alien8.de" <bp@alien8.de>,
        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
        "hpa@zytor.com" <hpa@zytor.com>
References: <20230224021858.120078-1-chenzhongjin@huawei.com>
 <dc0625d2-edaf-22fe-5eea-3088e95a2998@huawei.com>
 <96d44033-3bfd-840b-15d7-80dd3a1a5313@linux.intel.com>
From:   Chen Zhongjin <chenzhongjin@huawei.com>
In-Reply-To: <96d44033-3bfd-840b-15d7-80dd3a1a5313@linux.intel.com>
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On 2023/4/4 2:29, Andi Kleen wrote:
>
> On 4/2/2023 6:24 PM, Chen Zhongjin wrote:
>> Just ping... Or has profile code already been obsoleted?
>
>
> I think it would be reasonable to remove the locked functions hack 
> since lock profiling can be handled with much better other tools these 
> days.
>
> I wouldn't make it depend on the generic unwinder since such a low 
> level facility is likely better off without complex dependencies that 
> could break.
>
> -Andi
>
>
Although now the generic unwinder on x86 is quite stable... I think it's 
acceptable to remove the locked functions unwinding
for !FP case and leave the FP part as is.

I'll send a new patch for this with another bugfix.

Thanks for review and best,
Chen