| Message ID | 20230825132149.366064-5-david@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio-mem: Expose device memory through multiple memslots | expand |
On 25/8/23 15:21, David Hildenbrand wrote: > Let's return the number of free slots instead of only checking if there > is a free slot. While at it, check all address spaces, which will also > consider SMM under x86 correctly. > > Make the stub return UINT_MAX, such that we can call the function > unconditionally. > > This is a preparation for memory devices that consume multiple memslots. > > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > accel/kvm/kvm-all.c | 33 ++++++++++++++++++++------------- > accel/stubs/kvm-stub.c | 4 ++-- > hw/mem/memory-device.c | 2 +- > include/sysemu/kvm.h | 2 +- > include/sysemu/kvm_int.h | 1 + > 5 files changed, 25 insertions(+), 17 deletions(-) > diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c > index 235dc661bc..f39997d86e 100644 > --- a/accel/stubs/kvm-stub.c > +++ b/accel/stubs/kvm-stub.c > @@ -109,9 +109,9 @@ int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n, > return -ENOSYS; > } > > -bool kvm_has_free_slot(MachineState *ms) > +unsigned int kvm_get_free_memslots(void) > { > - return false; > + return UINT_MAX; Isn't it clearer returning 0 here and keeping kvm_enabled() below? > } > > void kvm_init_cpu_signals(CPUState *cpu) > diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c > index 667d56bd29..7c24685796 100644 > --- a/hw/mem/memory-device.c > +++ b/hw/mem/memory-device.c > @@ -59,7 +59,7 @@ static void memory_device_check_addable(MachineState *ms, MemoryRegion *mr, > const uint64_t size = memory_region_size(mr); > > /* we will need a new memory slot for kvm and vhost */ > - if (kvm_enabled() && !kvm_has_free_slot(ms)) { > + if (!kvm_get_free_memslots()) { (here) > error_setg(errp, "hypervisor has no free memory slots left"); > return; > } > diff --git a/include/sysemu/kvm_int.h b/include/sysemu/kvm_int.h > index 511b42bde5..8b09e78b12 100644 > --- a/include/sysemu/kvm_int.h > +++ b/include/sysemu/kvm_int.h > @@ -40,6 +40,7 @@ typedef struct KVMMemoryUpdate { > typedef struct KVMMemoryListener { > MemoryListener listener; > KVMSlot *slots; > + int nr_used_slots; Preferably using 'unsigned' here: Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
On 29.08.23 00:26, Philippe Mathieu-Daudé wrote: > On 25/8/23 15:21, David Hildenbrand wrote: >> Let's return the number of free slots instead of only checking if there >> is a free slot. While at it, check all address spaces, which will also >> consider SMM under x86 correctly. >> >> Make the stub return UINT_MAX, such that we can call the function >> unconditionally. >> >> This is a preparation for memory devices that consume multiple memslots. >> >> Signed-off-by: David Hildenbrand <david@redhat.com> >> --- >> accel/kvm/kvm-all.c | 33 ++++++++++++++++++++------------- >> accel/stubs/kvm-stub.c | 4 ++-- >> hw/mem/memory-device.c | 2 +- >> include/sysemu/kvm.h | 2 +- >> include/sysemu/kvm_int.h | 1 + >> 5 files changed, 25 insertions(+), 17 deletions(-) > > >> diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c >> index 235dc661bc..f39997d86e 100644 >> --- a/accel/stubs/kvm-stub.c >> +++ b/accel/stubs/kvm-stub.c >> @@ -109,9 +109,9 @@ int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n, >> return -ENOSYS; >> } >> >> -bool kvm_has_free_slot(MachineState *ms) >> +unsigned int kvm_get_free_memslots(void) >> { >> - return false; >> + return UINT_MAX; > > Isn't it clearer returning 0 here and keeping kvm_enabled() below? I tried doing it similarly to vhost_has_free_slot(). Also simplifies patch #12 :) No strong opinion, though. > > >> diff --git a/include/sysemu/kvm_int.h b/include/sysemu/kvm_int.h >> index 511b42bde5..8b09e78b12 100644 >> --- a/include/sysemu/kvm_int.h >> +++ b/include/sysemu/kvm_int.h >> @@ -40,6 +40,7 @@ typedef struct KVMMemoryUpdate { >> typedef struct KVMMemoryListener { >> MemoryListener listener; >> KVMSlot *slots; >> + int nr_used_slots; > > Preferably using 'unsigned' here: Sure, that should work. > > Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Thanks!
On 06.09.23 16:14, David Hildenbrand wrote: > On 29.08.23 00:26, Philippe Mathieu-Daudé wrote: >> On 25/8/23 15:21, David Hildenbrand wrote: >>> Let's return the number of free slots instead of only checking if there >>> is a free slot. While at it, check all address spaces, which will also >>> consider SMM under x86 correctly. >>> >>> Make the stub return UINT_MAX, such that we can call the function >>> unconditionally. >>> >>> This is a preparation for memory devices that consume multiple memslots. >>> >>> Signed-off-by: David Hildenbrand <david@redhat.com> >>> --- >>> accel/kvm/kvm-all.c | 33 ++++++++++++++++++++------------- >>> accel/stubs/kvm-stub.c | 4 ++-- >>> hw/mem/memory-device.c | 2 +- >>> include/sysemu/kvm.h | 2 +- >>> include/sysemu/kvm_int.h | 1 + >>> 5 files changed, 25 insertions(+), 17 deletions(-) >> >> >>> diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c >>> index 235dc661bc..f39997d86e 100644 >>> --- a/accel/stubs/kvm-stub.c >>> +++ b/accel/stubs/kvm-stub.c >>> @@ -109,9 +109,9 @@ int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n, >>> return -ENOSYS; >>> } >>> >>> -bool kvm_has_free_slot(MachineState *ms) >>> +unsigned int kvm_get_free_memslots(void) >>> { >>> - return false; >>> + return UINT_MAX; >> >> Isn't it clearer returning 0 here and keeping kvm_enabled() below? > > I tried doing it similarly to vhost_has_free_slot(). > I'll leave the kvm_enabled() check in place, looks cleaner.
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index d07f1ecbd3..0fcea923a1 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -181,6 +181,24 @@ int kvm_get_max_memslots(void) return s->nr_slots; } +unsigned int kvm_get_free_memslots(void) +{ + unsigned int used_slots = 0; + KVMState *s = kvm_state; + int i; + + kvm_slots_lock(); + for (i = 0; i < s->nr_as; i++) { + if (!s->as[i].ml) { + continue; + } + used_slots = MAX(used_slots, s->as[i].ml->nr_used_slots); + } + kvm_slots_unlock(); + + return s->nr_slots - used_slots; +} + /* Called with KVMMemoryListener.slots_lock held */ static KVMSlot *kvm_get_free_slot(KVMMemoryListener *kml) { @@ -196,19 +214,6 @@ static KVMSlot *kvm_get_free_slot(KVMMemoryListener *kml) return NULL; } -bool kvm_has_free_slot(MachineState *ms) -{ - KVMState *s = KVM_STATE(ms->accelerator); - bool result; - KVMMemoryListener *kml = &s->memory_listener; - - kvm_slots_lock(); - result = !!kvm_get_free_slot(kml); - kvm_slots_unlock(); - - return result; -} - /* Called with KVMMemoryListener.slots_lock held */ static KVMSlot *kvm_alloc_slot(KVMMemoryListener *kml) { @@ -1387,6 +1392,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, } start_addr += slot_size; size -= slot_size; + kml->nr_used_slots--; } while (size); return; } @@ -1412,6 +1418,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, ram_start_offset += slot_size; ram += slot_size; size -= slot_size; + kml->nr_used_slots++; } while (size); } diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c index 235dc661bc..f39997d86e 100644 --- a/accel/stubs/kvm-stub.c +++ b/accel/stubs/kvm-stub.c @@ -109,9 +109,9 @@ int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n, return -ENOSYS; } -bool kvm_has_free_slot(MachineState *ms) +unsigned int kvm_get_free_memslots(void) { - return false; + return UINT_MAX; } void kvm_init_cpu_signals(CPUState *cpu) diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c index 667d56bd29..7c24685796 100644 --- a/hw/mem/memory-device.c +++ b/hw/mem/memory-device.c @@ -59,7 +59,7 @@ static void memory_device_check_addable(MachineState *ms, MemoryRegion *mr, const uint64_t size = memory_region_size(mr); /* we will need a new memory slot for kvm and vhost */ - if (kvm_enabled() && !kvm_has_free_slot(ms)) { + if (!kvm_get_free_memslots()) { error_setg(errp, "hypervisor has no free memory slots left"); return; } diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index ccaf55caf7..321427a543 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -216,7 +216,7 @@ typedef struct KVMRouteChange { /* external API */ -bool kvm_has_free_slot(MachineState *ms); +unsigned int kvm_get_free_memslots(void); bool kvm_has_sync_mmu(void); int kvm_has_vcpu_events(void); int kvm_has_robust_singlestep(void); diff --git a/include/sysemu/kvm_int.h b/include/sysemu/kvm_int.h index 511b42bde5..8b09e78b12 100644 --- a/include/sysemu/kvm_int.h +++ b/include/sysemu/kvm_int.h @@ -40,6 +40,7 @@ typedef struct KVMMemoryUpdate { typedef struct KVMMemoryListener { MemoryListener listener; KVMSlot *slots; + int nr_used_slots; int as_id; QSIMPLEQ_HEAD(, KVMMemoryUpdate) transaction_add; QSIMPLEQ_HEAD(, KVMMemoryUpdate) transaction_del;
Let's return the number of free slots instead of only checking if there is a free slot. While at it, check all address spaces, which will also consider SMM under x86 correctly. Make the stub return UINT_MAX, such that we can call the function unconditionally. This is a preparation for memory devices that consume multiple memslots. Signed-off-by: David Hildenbrand <david@redhat.com> --- accel/kvm/kvm-all.c | 33 ++++++++++++++++++++------------- accel/stubs/kvm-stub.c | 4 ++-- hw/mem/memory-device.c | 2 +- include/sysemu/kvm.h | 2 +- include/sysemu/kvm_int.h | 1 + 5 files changed, 25 insertions(+), 17 deletions(-)