From 5b23186a954a88ecabb2696cd846e0e67a9e349c Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 26 Sep 2023 20:57:24 +0200 Subject: [PATCH] kvm: Return number of free memslots MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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. This is a preparation for memory devices that consume multiple memslots. Message-ID: <20230926185738.277351-5-david@redhat.com> Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Maciej S. Szmigiero Reviewed-by: Michael S. Tsirkin Signed-off-by: David Hildenbrand --- 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/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 72e1d1141c..5937e46e12 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..a5d4442d8f 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 0; } void kvm_init_cpu_signals(CPUState *cpu) diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c index 667d56bd29..98e355c960 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_enabled() && !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 ee9025f8e9..c3d831baef 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -215,7 +215,7 @@ 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 a5b9122cb8..075939a3c4 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; + unsigned int nr_used_slots; int as_id; QSIMPLEQ_HEAD(, KVMMemoryUpdate) transaction_add; QSIMPLEQ_HEAD(, KVMMemoryUpdate) transaction_del; -- 2.39.2