Message ID | 20170531092516.5112-1-lvivier@redhat.com |
---|---|
State | New |
Headers | show |
On Wed, 31 May 2017 11:25:16 +0200 Laurent Vivier <lvivier@redhat.com> wrote: > For QEMU, a hotlugged device is a device added using the HMP/QMP > interface. > For SPAPR, a hotplugged device is a device added while the > machine is running. In this case QEMU doesn't update internal > state but relies on the OS for this part > > In the case of migration, when we (libvirt) hotplug a device > on the source guest, we (libvirt) generally hotplug the same > device on the destination guest. But in this case, the machine > is stopped (RUN_STATE_INMIGRATE) and QEMU must not expect > the OS will manage it as an hotplugged device as it will > be "imported" by the migration. > > This patch changes the meaning of "hotplugged" in spapr.c > to manage a QEMU hotplugged device like a "coldplugged" one > when the machine is awaiting an incoming migration. > > Signed-off-by: Laurent Vivier <lvivier@redhat.com> > --- Reviewed-by: Greg Kurz <groug@kaod.org> > v2: > - don't replace dev->hotplugged to test if CPU hotplug > is supported. > > hw/ppc/spapr.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index ab3aab1..f0c543c 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -2521,6 +2521,12 @@ static void spapr_nmi(NMIState *n, int cpu_index, Error **errp) > } > } > > +static bool spapr_coldplugged(DeviceState *dev) > +{ > + return runstate_check(RUN_STATE_INMIGRATE) || > + !dev->hotplugged; > +} > + > static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > uint32_t node, bool dedicated_hp_event_source, > Error **errp) > @@ -2531,6 +2537,7 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > int i, fdt_offset, fdt_size; > void *fdt; > uint64_t addr = addr_start; > + bool coldplugged = spapr_coldplugged(dev); > > for (i = 0; i < nr_lmbs; i++) { > drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > @@ -2542,9 +2549,9 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > SPAPR_MEMORY_BLOCK_SIZE); > > drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - drck->attach(drc, dev, fdt, fdt_offset, !dev->hotplugged, errp); > + drck->attach(drc, dev, fdt, fdt_offset, coldplugged, errp); > addr += SPAPR_MEMORY_BLOCK_SIZE; > - if (!dev->hotplugged) { > + if (coldplugged) { > /* guests expect coldplugged LMBs to be pre-allocated */ > drck->set_allocation_state(drc, SPAPR_DR_ALLOCATION_STATE_USABLE); > drck->set_isolation_state(drc, SPAPR_DR_ISOLATION_STATE_UNISOLATED); > @@ -2553,7 +2560,7 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > /* send hotplug notification to the > * guest only in case of hotplugged memory > */ > - if (dev->hotplugged) { > + if (!coldplugged) { > if (dedicated_hp_event_source) { > drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > addr_start / SPAPR_MEMORY_BLOCK_SIZE); > @@ -2867,6 +2874,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, > int smt = kvmppc_smt_threads(); > CPUArchId *core_slot; > int index; > + bool coldplugged = spapr_coldplugged(dev); > > core_slot = spapr_find_cpu_slot(MACHINE(hotplug_dev), cc->core_id, &index); > if (!core_slot) { > @@ -2888,7 +2896,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, > > if (drc) { > sPAPRDRConnectorClass *drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - drck->attach(drc, dev, fdt, fdt_offset, !dev->hotplugged, &local_err); > + drck->attach(drc, dev, fdt, fdt_offset, coldplugged, &local_err); > if (local_err) { > g_free(fdt); > error_propagate(errp, local_err); > @@ -2896,7 +2904,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, > } > } > > - if (dev->hotplugged) { > + if (!coldplugged) { > /* > * Send hotplug notification interrupt to the guest only in case > * of hotplugged CPUs.
Hi, This series seems to have some coding style problems. See output below for more information: Subject: [Qemu-devel] [PATCH v2] spapr: manage hotplugged devices while the VM is not started Type: series Message-id: 20170531092516.5112-1-lvivier@redhat.com === TEST SCRIPT BEGIN === #!/bin/bash BASE=base n=1 total=$(git log --oneline $BASE.. | wc -l) failed=0 git config --local diff.renamelimit 0 git config --local diff.renames True commits="$(git log --format=%H --reverse $BASE..)" for c in $commits; do echo "Checking PATCH $n/$total: $(git log -n 1 --format=%s $c)..." if ! git show $c --format=email | ./scripts/checkpatch.pl --mailback -; then failed=1 echo fi n=$((n+1)) done exit $failed === TEST SCRIPT END === Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384 fatal: unable to access 'https://github.com/patchew-project/qemu/': Failed to connect to github.com port 443: Connection timed out error: Could not fetch 3c8cf5a9c21ff8782164d1def7f44bd888713384 Traceback (most recent call last): File "/usr/bin/patchew", line 409, in test_one git_clone_repo(clone, r["repo"], r["head"], logf) File "/usr/bin/patchew", line 48, in git_clone_repo stdout=logf, stderr=logf) File "/usr/lib64/python3.5/subprocess.py", line 581, in check_call raise CalledProcessError(retcode, cmd) subprocess.CalledProcessError: Command '['git', 'remote', 'add', '-f', '--mirror=fetch', '3c8cf5a9c21ff8782164d1def7f44bd888713384', 'https://github.com/patchew-project/qemu']' returned non-zero exit status 1 --- Email generated automatically by Patchew [http://patchew.org/]. Please send your feedback to patchew-devel@freelists.org
On Wed, May 31, 2017 at 11:25:16AM +0200, Laurent Vivier wrote: > For QEMU, a hotlugged device is a device added using the HMP/QMP > interface. > For SPAPR, a hotplugged device is a device added while the > machine is running. In this case QEMU doesn't update internal > state but relies on the OS for this part > > In the case of migration, when we (libvirt) hotplug a device > on the source guest, we (libvirt) generally hotplug the same > device on the destination guest. But in this case, the machine > is stopped (RUN_STATE_INMIGRATE) and QEMU must not expect > the OS will manage it as an hotplugged device as it will > be "imported" by the migration. > > This patch changes the meaning of "hotplugged" in spapr.c > to manage a QEMU hotplugged device like a "coldplugged" one > when the machine is awaiting an incoming migration. > > Signed-off-by: Laurent Vivier <lvivier@redhat.com> > --- > v2: > - don't replace dev->hotplugged to test if CPU hotplug > is supported. So, this addresses the specific points mentioned on the last version, but not the wider query: what exactly in the previous behaviour was causing problems. On a related note, having better understood the DRC code while writing my cleanups, I'm reconsidering your earlier suggestion of simply disabling hotplugs until after CAS. I rejected that approach before because I was assuming the problem was due to hotplug events being lost, and I was confident that CAS marked a transition from losing to not-losing events (other than by accident). However, later discussions have shown that the problem is more to do with device tree updates being essentially duplicated between the DT given to the guest during CAS and further updates from hotplug events. On that new understanding CAS does seem like a logical watershed, since it's the point at which the guest gets the final version of the "cold plugged" device tree. I still have some concerns about the details, but the basic approach seems sound. Sorry for the misdirection. > > hw/ppc/spapr.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index ab3aab1..f0c543c 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -2521,6 +2521,12 @@ static void spapr_nmi(NMIState *n, int cpu_index, Error **errp) > } > } > > +static bool spapr_coldplugged(DeviceState *dev) > +{ > + return runstate_check(RUN_STATE_INMIGRATE) || > + !dev->hotplugged; > +} > + > static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > uint32_t node, bool dedicated_hp_event_source, > Error **errp) > @@ -2531,6 +2537,7 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > int i, fdt_offset, fdt_size; > void *fdt; > uint64_t addr = addr_start; > + bool coldplugged = spapr_coldplugged(dev); > > for (i = 0; i < nr_lmbs; i++) { > drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > @@ -2542,9 +2549,9 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > SPAPR_MEMORY_BLOCK_SIZE); > > drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - drck->attach(drc, dev, fdt, fdt_offset, !dev->hotplugged, errp); > + drck->attach(drc, dev, fdt, fdt_offset, coldplugged, errp); > addr += SPAPR_MEMORY_BLOCK_SIZE; > - if (!dev->hotplugged) { > + if (coldplugged) { > /* guests expect coldplugged LMBs to be pre-allocated */ > drck->set_allocation_state(drc, SPAPR_DR_ALLOCATION_STATE_USABLE); > drck->set_isolation_state(drc, SPAPR_DR_ISOLATION_STATE_UNISOLATED); > @@ -2553,7 +2560,7 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, > /* send hotplug notification to the > * guest only in case of hotplugged memory > */ > - if (dev->hotplugged) { > + if (!coldplugged) { > if (dedicated_hp_event_source) { > drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > addr_start / SPAPR_MEMORY_BLOCK_SIZE); > @@ -2867,6 +2874,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, > int smt = kvmppc_smt_threads(); > CPUArchId *core_slot; > int index; > + bool coldplugged = spapr_coldplugged(dev); > > core_slot = spapr_find_cpu_slot(MACHINE(hotplug_dev), cc->core_id, &index); > if (!core_slot) { > @@ -2888,7 +2896,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, > > if (drc) { > sPAPRDRConnectorClass *drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - drck->attach(drc, dev, fdt, fdt_offset, !dev->hotplugged, &local_err); > + drck->attach(drc, dev, fdt, fdt_offset, coldplugged, &local_err); > if (local_err) { > g_free(fdt); > error_propagate(errp, local_err); > @@ -2896,7 +2904,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, > } > } > > - if (dev->hotplugged) { > + if (!coldplugged) { > /* > * Send hotplug notification interrupt to the guest only in case > * of hotplugged CPUs.
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index ab3aab1..f0c543c 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -2521,6 +2521,12 @@ static void spapr_nmi(NMIState *n, int cpu_index, Error **errp) } } +static bool spapr_coldplugged(DeviceState *dev) +{ + return runstate_check(RUN_STATE_INMIGRATE) || + !dev->hotplugged; +} + static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, uint32_t node, bool dedicated_hp_event_source, Error **errp) @@ -2531,6 +2537,7 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, int i, fdt_offset, fdt_size; void *fdt; uint64_t addr = addr_start; + bool coldplugged = spapr_coldplugged(dev); for (i = 0; i < nr_lmbs; i++) { drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, @@ -2542,9 +2549,9 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, SPAPR_MEMORY_BLOCK_SIZE); drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); - drck->attach(drc, dev, fdt, fdt_offset, !dev->hotplugged, errp); + drck->attach(drc, dev, fdt, fdt_offset, coldplugged, errp); addr += SPAPR_MEMORY_BLOCK_SIZE; - if (!dev->hotplugged) { + if (coldplugged) { /* guests expect coldplugged LMBs to be pre-allocated */ drck->set_allocation_state(drc, SPAPR_DR_ALLOCATION_STATE_USABLE); drck->set_isolation_state(drc, SPAPR_DR_ISOLATION_STATE_UNISOLATED); @@ -2553,7 +2560,7 @@ static void spapr_add_lmbs(DeviceState *dev, uint64_t addr_start, uint64_t size, /* send hotplug notification to the * guest only in case of hotplugged memory */ - if (dev->hotplugged) { + if (!coldplugged) { if (dedicated_hp_event_source) { drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, addr_start / SPAPR_MEMORY_BLOCK_SIZE); @@ -2867,6 +2874,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, int smt = kvmppc_smt_threads(); CPUArchId *core_slot; int index; + bool coldplugged = spapr_coldplugged(dev); core_slot = spapr_find_cpu_slot(MACHINE(hotplug_dev), cc->core_id, &index); if (!core_slot) { @@ -2888,7 +2896,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, if (drc) { sPAPRDRConnectorClass *drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); - drck->attach(drc, dev, fdt, fdt_offset, !dev->hotplugged, &local_err); + drck->attach(drc, dev, fdt, fdt_offset, coldplugged, &local_err); if (local_err) { g_free(fdt); error_propagate(errp, local_err); @@ -2896,7 +2904,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev, } } - if (dev->hotplugged) { + if (!coldplugged) { /* * Send hotplug notification interrupt to the guest only in case * of hotplugged CPUs.
For QEMU, a hotlugged device is a device added using the HMP/QMP interface. For SPAPR, a hotplugged device is a device added while the machine is running. In this case QEMU doesn't update internal state but relies on the OS for this part In the case of migration, when we (libvirt) hotplug a device on the source guest, we (libvirt) generally hotplug the same device on the destination guest. But in this case, the machine is stopped (RUN_STATE_INMIGRATE) and QEMU must not expect the OS will manage it as an hotplugged device as it will be "imported" by the migration. This patch changes the meaning of "hotplugged" in spapr.c to manage a QEMU hotplugged device like a "coldplugged" one when the machine is awaiting an incoming migration. Signed-off-by: Laurent Vivier <lvivier@redhat.com> --- v2: - don't replace dev->hotplugged to test if CPU hotplug is supported. hw/ppc/spapr.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)