From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53619) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1acxwt-0002ts-Ga for qemu-devel@nongnu.org; Mon, 07 Mar 2016 11:24:00 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1acxwq-0008FS-A2 for qemu-devel@nongnu.org; Mon, 07 Mar 2016 11:23:59 -0500 References: <1457074461-14285-1-git-send-email-bharata@linux.vnet.ibm.com> <1457074461-14285-2-git-send-email-bharata@linux.vnet.ibm.com> From: Thomas Huth Message-ID: <56DDAB14.8020507@redhat.com> Date: Mon, 7 Mar 2016 17:23:48 +0100 MIME-Version: 1.0 In-Reply-To: <1457074461-14285-2-git-send-email-bharata@linux.vnet.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [RFC PATCH v1 01/10] exec: Remove cpu from cpus list during cpu_exec_exit() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bharata B Rao , 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 04.03.2016 07:54, Bharata B Rao wrote: > CPUState *cpu gets added to the cpus list during cpu_exec_init(). It > should be removed from cpu_exec_exit(). >=20 > cpu_exec_init() is called from generic CPU::instance_finalize and some s/cpu_exec_init/cpu_exec_exit/ > archs like PowerPC call it from CPU unrealizefn. So ensure that we > dequeue the cpu only once. >=20 > Now -1 value for cpu->cpu_index indicates that we have already dequeued > the cpu for CONFIG_USER_ONLY case also. >=20 > Signed-off-by: Bharata B Rao > --- > exec.c | 32 ++++++++++++++++++++++++-------- > 1 file changed, 24 insertions(+), 8 deletions(-) >=20 > diff --git a/exec.c b/exec.c > index c62c439..7c3f747 100644 > --- a/exec.c > +++ b/exec.c > @@ -588,15 +588,9 @@ static int cpu_get_free_index(Error **errp) > return cpu; > } > =20 > -void cpu_exec_exit(CPUState *cpu) > +static void cpu_release_index(CPUState *cpu) > { > - if (cpu->cpu_index =3D=3D -1) { > - /* cpu_index was never allocated by this @cpu or was already f= reed. */ > - return; > - } > - > bitmap_clear(cpu_index_map, cpu->cpu_index, 1); > - cpu->cpu_index =3D -1; > } > #else > =20 > @@ -611,11 +605,33 @@ static int cpu_get_free_index(Error **errp) > return cpu_index; > } > =20 > -void cpu_exec_exit(CPUState *cpu) > +static void cpu_release_index(CPUState *cpu) > { > + return; You could also simply leave that return statement away, I think. > } > #endif > =20 > +void cpu_exec_exit(CPUState *cpu) > +{ > +#if defined(CONFIG_USER_ONLY) > + cpu_list_lock(); > +#endif > + if (cpu->cpu_index =3D=3D -1) { > + /* cpu_index was never allocated by this @cpu or was already f= reed. */ > +#if defined(CONFIG_USER_ONLY) > + cpu_list_unlock(); > +#endif > + return; > + } > + > + QTAILQ_REMOVE(&cpus, cpu, node); > + cpu_release_index(cpu); > + cpu->cpu_index =3D -1; > +#if defined(CONFIG_USER_ONLY) > + cpu_list_unlock(); > +#endif > +} Since there are a couple of these #if defined(CONFIG_USER_ONLY) cpu_list_[un]lock(); #endif in exec.c already, it might be somewhat nices to declare them at the beginning of the file as empty functions, somewhat like: #if !defined(CONFIG_USER_ONLY) static inline void cpu_list_lock(void) { } static inline void cpu_list_unlock(void) { } #endif What do you think about that? Apart from that, the patch looks fine to me. Thomas