From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Otte Date: Fri, 21 May 2010 07:35:03 +0000 Subject: Re: [PATCH 0/7] Consolidate vcpu ioctl locking Message-Id: <4BF637A7.3010203@de.ibm.com> List-Id: References: <1273749459-622-1-git-send-email-avi@redhat.com> In-Reply-To: <1273749459-622-1-git-send-email-avi@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ia64@vger.kernel.org On 15.05.2010 10:26, Alexander Graf wrote: > On S390, I'm also still sceptical if the implementation we have really works. A device injects an S390_INTERRUPT with its address and on the next vcpu_run, an according interrupt is issued. But what happens if two devices trigger an S390_INTERRUPT before the vcpu_run? We'd have lost an interrupt by then... We're safe on that: the interrupt info field in both struct kvm (for floating interrupts) and struct vcpu (for cpu local interrupts) have their own locking and can queue up interrupts. cheers, Carsten From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Otte Date: Fri, 21 May 2010 07:35:03 +0000 Subject: Re: [PATCH 0/7] Consolidate vcpu ioctl locking Message-Id: <4BF637A7.3010203@de.ibm.com> List-Id: References: <1273749459-622-1-git-send-email-avi@redhat.com> <4BEBEA25.8080309@redhat.com> <4BEBEA7E.80202@redhat.com> <4BEBEAAE.9030502@redhat.com> <24423079-CDE0-4DEA-BC73-3B6976BE0CA6@suse.de> <4BEBF0BF.2020404@redhat.com> <4BEE3C56.2070007@redhat.com> <4BEE544B.50405@redhat.com> <20442124-2400-4273-A256-6846017D3141@suse.de> In-Reply-To: <20442124-2400-4273-A256-6846017D3141-l3A5Bk7waGM@public.gmane.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Alexander Graf Cc: Avi Kivity , Marcelo Tosatti , "kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "kvm-ia64-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "kvm-ppc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" On 15.05.2010 10:26, Alexander Graf wrote: > On S390, I'm also still sceptical if the implementation we have really works. A device injects an S390_INTERRUPT with its address and on the next vcpu_run, an according interrupt is issued. But what happens if two devices trigger an S390_INTERRUPT before the vcpu_run? We'd have lost an interrupt by then... We're safe on that: the interrupt info field in both struct kvm (for floating interrupts) and struct vcpu (for cpu local interrupts) have their own locking and can queue up interrupts. cheers, Carsten From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Otte Subject: Re: [PATCH 0/7] Consolidate vcpu ioctl locking Date: Fri, 21 May 2010 09:35:03 +0200 Message-ID: <4BF637A7.3010203@de.ibm.com> References: <1273749459-622-1-git-send-email-avi@redhat.com> <4BEBEA25.8080309@redhat.com> <4BEBEA7E.80202@redhat.com> <4BEBEAAE.9030502@redhat.com> <24423079-CDE0-4DEA-BC73-3B6976BE0CA6@suse.de> <4BEBF0BF.2020404@redhat.com> <4BEE3C56.2070007@redhat.com> <4BEE544B.50405@redhat.com> <20442124-2400-4273-A256-6846017D3141@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Marcelo Tosatti , "kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "kvm-ia64-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "kvm-ppc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" To: Alexander Graf Return-path: In-Reply-To: <20442124-2400-4273-A256-6846017D3141-l3A5Bk7waGM@public.gmane.org> Sender: kvm-ppc-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: kvm.vger.kernel.org On 15.05.2010 10:26, Alexander Graf wrote: > On S390, I'm also still sceptical if the implementation we have really works. A device injects an S390_INTERRUPT with its address and on the next vcpu_run, an according interrupt is issued. But what happens if two devices trigger an S390_INTERRUPT before the vcpu_run? We'd have lost an interrupt by then... We're safe on that: the interrupt info field in both struct kvm (for floating interrupts) and struct vcpu (for cpu local interrupts) have their own locking and can queue up interrupts. cheers, Carsten