From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37781) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aeF6T-0004l2-9R for qemu-devel@nongnu.org; Thu, 10 Mar 2016 23:55:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aeF6R-00049M-1q for qemu-devel@nongnu.org; Thu, 10 Mar 2016 23:55:09 -0500 Received: from e28smtp05.in.ibm.com ([125.16.236.5]:55186) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aeF6Q-00045m-CU for qemu-devel@nongnu.org; Thu, 10 Mar 2016 23:55:06 -0500 Received: from localhost by e28smtp05.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 11 Mar 2016 10:25:03 +0530 From: Bharata B Rao Date: Fri, 11 Mar 2016 10:24:33 +0530 Message-Id: <1457672078-17307-5-git-send-email-bharata@linux.vnet.ibm.com> In-Reply-To: <1457672078-17307-1-git-send-email-bharata@linux.vnet.ibm.com> References: <1457672078-17307-1-git-send-email-bharata@linux.vnet.ibm.com> Subject: [Qemu-devel] [RFC PATCH v2 4/9] cpu: Add a sync version of cpu_remove() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: mjrosato@linux.vnet.ibm.com, thuth@redhat.com, pkrempa@redhat.com, ehabkost@redhat.com, aik@ozlabs.ru, Bharata B Rao , 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 This sync API will be used by the CPU hotplug code to wait for the CPU to completely get removed before flagging the failure to the device_add command. Sync version of this call is needed to correctly recover from CPU realization failures when ->plug() handler fails. Signed-off-by: Bharata B Rao Reviewed-by: David Gibson --- cpus.c | 12 ++++++++++++ include/qom/cpu.h | 8 ++++++++ 2 files changed, 20 insertions(+) diff --git a/cpus.c b/cpus.c index be0ac6a..05cb096 100644 --- a/cpus.c +++ b/cpus.c @@ -1068,6 +1068,8 @@ static void *qemu_kvm_cpu_thread_fn(void *arg) } while (!cpu->unplug || cpu_can_run(cpu)); qemu_kvm_destroy_vcpu(cpu); + cpu->created = false; + qemu_cond_signal(&qemu_cpu_cond); qemu_mutex_unlock_iothread(); return NULL; } @@ -1168,6 +1170,8 @@ static void *qemu_tcg_cpu_thread_fn(void *arg) } if (remove_cpu) { qemu_tcg_destroy_vcpu(remove_cpu); + cpu->created = false; + qemu_cond_signal(&qemu_cpu_cond); remove_cpu = NULL; } } @@ -1333,6 +1337,14 @@ void cpu_remove(CPUState *cpu) qemu_cpu_kick(cpu); } +void cpu_remove_sync(CPUState *cpu) +{ + cpu_remove(cpu); + while (cpu->created) { + qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex); + } +} + /* For temporary buffers for forming a name */ #define VCPU_THREAD_NAME_SIZE 16 diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 0720dd7..6e20119 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -765,6 +765,14 @@ void cpu_resume(CPUState *cpu); */ void cpu_remove(CPUState *cpu); + /** + * cpu_remove_sync: + * @cpu: The CPU to remove. + * + * Requests the CPU to be removed and waits till it is removed. + */ +void cpu_remove_sync(CPUState *cpu); + /** * qemu_init_vcpu: * @cpu: The vCPU to initialize. -- 2.1.0