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From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <71bba48c-317f-b553-ad27-ae6ca66cb878@redhat.com>
Date: Thu, 4 May 2017 09:38:06 +0200
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Subject: Re: [Qemu-devel] [PATCH 09/17] util: add stats64 module
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To: Fam Zheng <famz@redhat.com>
Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org



On 04/05/2017 09:36, Fam Zheng wrote:
>> +
>> +    /* If there is a concurrent writer, wait for it.  */
>> +    while (atomic_read(&s->lock) & 1) {
>> +        g_usleep(5);
> What's the difference of g_usleep() from cpu_relax() in
> qemu_co_mutex_lock_unlock?

cpu_relax() did not exist when I wrote this patch. :)  I'll change it.

Paolo