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From:   Florian Weimer <fweimer@redhat.com>
To:     Gavin Shan <gshan@redhat.com>
Cc:     kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
        linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org,
        pbonzini@redhat.com, maz@kernel.org, oliver.upton@linux.dev,
        andrew.jones@linux.dev, seanjc@google.com,
        mathieu.desnoyers@efficios.com, yihyu@redhat.com,
        shan.gavin@gmail.com
Subject: Re: [PATCH 2/2] KVM: selftests: Use getcpu() instead of
 sched_getcpu() in rseq_test
References: <20220809060627.115847-1-gshan@redhat.com>
        <20220809060627.115847-3-gshan@redhat.com>
Date:   Tue, 09 Aug 2022 08:35:14 +0200
In-Reply-To: <20220809060627.115847-3-gshan@redhat.com> (Gavin Shan's message
        of "Tue, 9 Aug 2022 14:06:27 +0800")
Message-ID: <87y1vxncv1.fsf@oldenburg.str.redhat.com>
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* Gavin Shan:

> sched_getcpu() is glibc dependent and it can simply return the CPU
> ID from the registered rseq information, as Florian Weimer pointed.
> In this case, it's pointless to compare the return value from
> sched_getcpu() and that fetched from the registered rseq information.
>
> Fix the issue by replacing sched_getcpu() with getcpu(), as Florian
> suggested. The comments are modified accordingly.

Note that getcpu was added in glibc 2.29, so perhaps you need to perform
a direct system call?

Thanks,
Florian