From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:48754)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <thuth@redhat.com>) id 1aeLL9-0002jx-TY
	for qemu-devel@nongnu.org; Fri, 11 Mar 2016 06:34:44 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <thuth@redhat.com>) id 1aeLL6-0004re-O2
	for qemu-devel@nongnu.org; Fri, 11 Mar 2016 06:34:43 -0500
References: <1457672078-17307-1-git-send-email-bharata@linux.vnet.ibm.com>
	<1457672078-17307-2-git-send-email-bharata@linux.vnet.ibm.com>
From: Thomas Huth <thuth@redhat.com>
Message-ID: <56E2AD40.5060606@redhat.com>
Date: Fri, 11 Mar 2016 12:34:24 +0100
MIME-Version: 1.0
In-Reply-To: <1457672078-17307-2-git-send-email-bharata@linux.vnet.ibm.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [RFC PATCH v2 1/9] exec: Remove cpu from cpus list
 during cpu_exec_exit()
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Bharata B Rao <bharata@linux.vnet.ibm.com>, qemu-devel@nongnu.org
Cc: mjrosato@linux.vnet.ibm.com, pkrempa@redhat.com, ehabkost@redhat.com, aik@ozlabs.ru, armbru@redhat.com, agraf@suse.de, borntraeger@de.ibm.com, qemu-ppc@nongnu.org, pbonzini@redhat.com, imammedo@redhat.com, mdroth@linux.vnet.ibm.com, afaerber@suse.de, david@gibson.dropbear.id.au

On 11.03.2016 05:54, Bharata B Rao wrote:
> CPUState *cpu gets added to the cpus list during cpu_exec_init(). It
> should be removed from cpu_exec_exit().
> 
> cpu_exec_exit() is called from generic CPU::instance_finalize and some
> archs like PowerPC call it from CPU unrealizefn. So ensure that we
> dequeue the cpu only once.
> 
> Now -1 value for cpu->cpu_index indicates that we have already dequeued
> the cpu for CONFIG_USER_ONLY case also.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>  exec.c | 32 ++++++++++++++++++++++++--------
>  1 file changed, 24 insertions(+), 8 deletions(-)
> 
> diff --git a/exec.c b/exec.c
> index f09dd4e..49ae593 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -609,15 +609,9 @@ static int cpu_get_free_index(Error **errp)
>      return cpu;
>  }
>  
> -void cpu_exec_exit(CPUState *cpu)
> +static void cpu_release_index(CPUState *cpu)
>  {
> -    if (cpu->cpu_index == -1) {
> -        /* cpu_index was never allocated by this @cpu or was already freed. */
> -        return;
> -    }
> -
>      bitmap_clear(cpu_index_map, cpu->cpu_index, 1);
> -    cpu->cpu_index = -1;
>  }
>  #else
>  
> @@ -632,11 +626,33 @@ static int cpu_get_free_index(Error **errp)
>      return cpu_index;
>  }
>  
> -void cpu_exec_exit(CPUState *cpu)
> +static void cpu_release_index(CPUState *cpu)
>  {
> +    return;
>  }
>  #endif
>  
> +void cpu_exec_exit(CPUState *cpu)
> +{
> +#if defined(CONFIG_USER_ONLY)
> +    cpu_list_lock();
> +#endif
> +    if (cpu->cpu_index == -1) {
> +        /* cpu_index was never allocated by this @cpu or was already freed. */
> +#if defined(CONFIG_USER_ONLY)
> +        cpu_list_unlock();
> +#endif
> +        return;
> +    }
> +
> +    QTAILQ_REMOVE(&cpus, cpu, node);
> +    cpu_release_index(cpu);
> +    cpu->cpu_index = -1;
> +#if defined(CONFIG_USER_ONLY)
> +    cpu_list_unlock();
> +#endif
> +}
> +
>  void cpu_exec_init(CPUState *cpu, Error **errp)
>  {
>      CPUClass *cc = CPU_GET_CLASS(cpu);
> 

Reviewed-by: Thomas Huth <thuth@redhat.com>