search for: vcpuop_down

The xen_play_dead is an undead function. When the vCPU is told to offline it ends up calling xen_play_dead wherin it calls the VCPUOP_down hypercall which offlines the vCPU. However, when the vCPU is onlined back, it resumes execution right after VCPUOP_down hypercall. That was OK (albeit the API for play_dead assumes that the CPU stays dead and never returns) but with commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down) th...

...ions(+), 8 deletions(-) diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 09a7199..602d6b7 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -417,14 +417,6 @@ static void __cpuinit xen_play_dead(void) /* used only with HOTPLUG_CPU */ { play_dead_common(); HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL); - cpu_bringup(); - /* - * Balance out the preempt calls - as we are running in cpu_idle - * loop which has been called at bootup from cpu_bringup_and_idle. - * The cpucpu_bringup_and_idle called cpu_bringup which made a - * preempt_disable() So this preempt_enable wi...

...ions(+), 8 deletions(-) diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 09a7199..602d6b7 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -417,14 +417,6 @@ static void __cpuinit xen_play_dead(void) /* used only with HOTPLUG_CPU */ { play_dead_common(); HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL); - cpu_bringup(); - /* - * Balance out the preempt calls - as we are running in cpu_idle - * loop which has been called at bootup from cpu_bringup_and_idle. - * The cpucpu_bringup_and_idle called cpu_bringup which made a - * preempt_disable() So this preempt_enable wi...

...to report that the vcpu is down: while (HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) { current->state = TASK_UNINTERRUPTIBLE; schedule_timeout(HZ/10); } the critical difference is that play_dead in arch/i386/process-xen.c and arch/x86_64/process-xen.c differ. the i386 version makes a VCPUOP_down call to the hypervisor while the x86_64 version schedules a SCHEDOP_yield among other things. plopping the i386 version (patch below) into x86_64/process-xen.c makes hotplugging in x86_64 behavior like i386. does anyone know why the x86_64 play_dead function is in the current state? thanks, ryan...

...should be used. There are two major tricks in regards to CPU, page tables, LDT and GDT management and CPU stopping during crash. Xen does not allow you to destroy CPU context if it was started. This behavior makes a lot of difficulties if SMP system must be restarted. Every CPU could be stopped by VCPUOP_down but page tables, LDT and GDT used when VCPUOP_down is executed on given procesor are locked (e.g. page tables are pinned and they must be unpinned before destroying them). This way those CPU strutures could not be destroyed. There is workaround which gives a chance to stop all unneeded processors i...

...should be used. There are two major tricks in regards to CPU, page tables, LDT and GDT management and CPU stopping during crash. Xen does not allow you to destroy CPU context if it was started. This behavior makes a lot of difficulties if SMP system must be restarted. Every CPU could be stopped by VCPUOP_down but page tables, LDT and GDT used when VCPUOP_down is executed on given procesor are locked (e.g. page tables are pinned and they must be unpinned before destroying them). This way those CPU strutures could not be destroyed. There is workaround which gives a chance to stop all unneeded processors i...

...should be used. There are two major tricks in regards to CPU, page tables, LDT and GDT management and CPU stopping during crash. Xen does not allow you to destroy CPU context if it was started. This behavior makes a lot of difficulties if SMP system must be restarted. Every CPU could be stopped by VCPUOP_down but page tables, LDT and GDT used when VCPUOP_down is executed on given procesor are locked (e.g. page tables are pinned and they must be unpinned before destroying them). This way those CPU strutures could not be destroyed. There is workaround which gives a chance to stop all unneeded processors i...

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-rc7 + your patches + the last batch of pv_ops patches I posted. This patch generally restricts itself to Xen-specific parts of the tree, though it does make a few small changes elsewhere. These patches include: - some helper routines for allocating address space and walking pagetables - Xen

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-rc7 + your patches + the last batch of pv_ops patches I posted. This patch generally restricts itself to Xen-specific parts of the tree, though it does make a few small changes elsewhere. These patches include: - some helper routines for allocating address space and walking pagetables - Xen

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-git13 + patches-2.6.21-git7-070507-1.tar.gz (I think "unwinder" is the only patch which doesn't apply to git13, and the sched-clock patches are the only ones which this series actually needs). Changes since the last posting: - More netfront review and cleanup - Added ability to

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-git13 + patches-2.6.21-git7-070507-1.tar.gz (I think "unwinder" is the only patch which doesn't apply to git13, and the sched-clock patches are the only ones which this series actually needs). Changes since the last posting: - More netfront review and cleanup - Added ability to

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-git13 + patches-2.6.21-git7-070507-1.tar.gz (I think "unwinder" is the only patch which doesn't apply to git13, and the sched-clock patches are the only ones which this series actually needs). Changes since the last posting: - More netfront review and cleanup - Added ability to

Hi, This is the Xen implementation for the paravirt_ops interface. The series is based on 2.6.22-rc1-mm1, and I think its ready to be cooked in -mm with a view to being merged in 2.6.23. The first part of the series is some small changes to the core kernel. Apart from the new code added in "Allocate and free vmalloc areas" (posted many times before), they are simply a few one-liners

Hi, This is the Xen implementation for the paravirt_ops interface. The series is based on 2.6.22-rc1-mm1, and I think its ready to be cooked in -mm with a view to being merged in 2.6.23. The first part of the series is some small changes to the core kernel. Apart from the new code added in "Allocate and free vmalloc areas" (posted many times before), they are simply a few one-liners

Hi, This is the Xen implementation for the paravirt_ops interface. The series is based on 2.6.22-rc1-mm1, and I think its ready to be cooked in -mm with a view to being merged in 2.6.23. The first part of the series is some small changes to the core kernel. Apart from the new code added in "Allocate and free vmalloc areas" (posted many times before), they are simply a few one-liners

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-git3 + ff patches-2.6.21-git3-070501-1.tar.gz. Changes since the last posting: - reviews of xenbus (me), netfront (hch, rusty, herbert xu) and blockfront (hch), with most comments addressed. Netfront review revealed a couple of real bugs, and the code for all three is looking cleaner

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21-git3 + ff patches-2.6.21-git3-070501-1.tar.gz. Changes since the last posting: - reviews of xenbus (me), netfront (hch, rusty, herbert xu) and blockfront (hch), with most comments addressed. Netfront review revealed a couple of real bugs, and the code for all three is looking cleaner

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21 + 2.6.21-070428-1 + the patches I've posted over the last couple of days. Changes since the last posting: - update per review comments - comment each file - comment barrier use - use common cpu sibling setup - fixed a few minor bugs, specifically a traceirq mismatch warning - some

Hi Andi, This series of patches implements the Xen paravirt-ops interface. It applies to 2.6.21 + 2.6.21-070428-1 + the patches I've posted over the last couple of days. Changes since the last posting: - update per review comments - comment each file - comment barrier use - use common cpu sibling setup - fixed a few minor bugs, specifically a traceirq mismatch warning - some

Hi Andi, This patch series implements the Linux Xen guest as a paravirt_ops backend. The features in implemented this patch series are: * domU only * UP and SMP guest support (NEW!) * dynamic ticks (NEW!) * writable pagetables, with late pinning/early unpinning (no shadow pagetable support) * supports both PAE and non-PAE modes (non-PAE may be broken at the moment) * xen hvc console