@@ -25,6 +25,12 @@
#define XICS_MFRR 0xc
#define XICS_IPI 2 /* interrupt source # for IPIs */
+/* Maximum number of threads per physical core */
+#define MAX_SMT_THREADS 8
+
+/* Maximum number of subcores per physical core */
+#define MAX_SUBCORES 4
+
#ifdef __ASSEMBLY__
#ifdef CONFIG_KVM_BOOK3S_HANDLER
@@ -65,6 +71,19 @@ kvmppc_resume_\intno:
#else /*__ASSEMBLY__ */
+struct kvmppc_vcore;
+
+/* Struct used for coordinating micro-threading (split-core) mode changes */
+struct kvm_split_mode {
+ unsigned long rpr;
+ unsigned long pmmar;
+ unsigned long ldbar;
+ u8 subcore_size;
+ u8 do_nap;
+ u8 napped[MAX_SMT_THREADS];
+ struct kvmppc_vcore *master_vcs[MAX_SUBCORES];
+};
+
/*
* This struct goes in the PACA on 64-bit processors. It is used
* to store host state that needs to be saved when we enter a guest
@@ -100,6 +119,7 @@ struct kvmppc_host_state {
u64 host_spurr;
u64 host_dscr;
u64 dec_expires;
+ struct kvm_split_mode *kvm_split_mode;
#endif
#ifdef CONFIG_PPC_BOOK3S_64
u64 cfar;
@@ -302,6 +302,9 @@ struct kvmppc_vcore {
#define VCORE_EXIT_MAP(vc) ((vc)->entry_exit_map >> 8)
#define VCORE_IS_EXITING(vc) (VCORE_EXIT_MAP(vc) != 0)
+/* This bit is used when a vcore exit is triggered from outside the vcore */
+#define VCORE_EXIT_REQ 0x10000
+
/*
* Values for vcore_state.
* Note that these are arranged such that lower values
@@ -676,7 +676,14 @@ int main(void)
HSTATE_FIELD(HSTATE_DSCR, host_dscr);
HSTATE_FIELD(HSTATE_DABR, dabr);
HSTATE_FIELD(HSTATE_DECEXP, dec_expires);
+ HSTATE_FIELD(HSTATE_SPLIT_MODE, kvm_split_mode);
DEFINE(IPI_PRIORITY, IPI_PRIORITY);
+ DEFINE(KVM_SPLIT_RPR, offsetof(struct kvm_split_mode, rpr));
+ DEFINE(KVM_SPLIT_PMMAR, offsetof(struct kvm_split_mode, pmmar));
+ DEFINE(KVM_SPLIT_LDBAR, offsetof(struct kvm_split_mode, ldbar));
+ DEFINE(KVM_SPLIT_SIZE, offsetof(struct kvm_split_mode, subcore_size));
+ DEFINE(KVM_SPLIT_DO_NAP, offsetof(struct kvm_split_mode, do_nap));
+ DEFINE(KVM_SPLIT_NAPPED, offsetof(struct kvm_split_mode, napped));
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
#ifdef CONFIG_PPC_BOOK3S_64
@@ -81,6 +81,9 @@ static DECLARE_BITMAP(default_enabled_hcalls, MAX_HCALL_OPCODE/4 + 1);
#define MPP_BUFFER_ORDER 3
#endif
+static int dynamic_mt_modes = 6;
+module_param(dynamic_mt_modes, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dynamic_mt_modes, "Set of allowed dynamic micro-threading modes: 0 (= none), 2, 4, or 6 (= 2 or 4)");
static int target_smt_mode;
module_param(target_smt_mode, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(target_smt_mode, "Target threads per core (0 = max)");
@@ -1770,6 +1773,7 @@ static int kvmppc_grab_hwthread(int cpu)
/* Ensure the thread won't go into the kernel if it wakes */
tpaca->kvm_hstate.kvm_vcpu = NULL;
+ tpaca->kvm_hstate.kvm_vcore = NULL;
tpaca->kvm_hstate.napping = 0;
smp_wmb();
tpaca->kvm_hstate.hwthread_req = 1;
@@ -1801,28 +1805,32 @@ static void kvmppc_release_hwthread(int cpu)
tpaca = &paca[cpu];
tpaca->kvm_hstate.hwthread_req = 0;
tpaca->kvm_hstate.kvm_vcpu = NULL;
+ tpaca->kvm_hstate.kvm_vcore = NULL;
+ tpaca->kvm_hstate.kvm_split_mode = NULL;
}
-static void kvmppc_start_thread(struct kvm_vcpu *vcpu)
+static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc)
{
int cpu;
struct paca_struct *tpaca;
- struct kvmppc_vcore *vc = vcpu->arch.vcore;
struct kvmppc_vcore *mvc = vc->master_vcore;
- if (vcpu->arch.timer_running) {
- hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
- vcpu->arch.timer_running = 0;
+ cpu = vc->pcpu;
+ if (vcpu) {
+ if (vcpu->arch.timer_running) {
+ hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
+ vcpu->arch.timer_running = 0;
+ }
+ cpu += vcpu->arch.ptid;
+ vcpu->cpu = mvc->pcpu;
+ vcpu->arch.thread_cpu = cpu;
}
- cpu = vc->pcpu + vcpu->arch.ptid;
tpaca = &paca[cpu];
- tpaca->kvm_hstate.kvm_vcore = mvc;
+ tpaca->kvm_hstate.kvm_vcpu = vcpu;
tpaca->kvm_hstate.ptid = cpu - mvc->pcpu;
- vcpu->cpu = mvc->pcpu;
- vcpu->arch.thread_cpu = cpu;
/* Order stores to hstate.kvm_vcpu etc. before store to kvm_vcore */
smp_wmb();
- tpaca->kvm_hstate.kvm_vcpu = vcpu;
+ tpaca->kvm_hstate.kvm_vcore = mvc;
if (cpu != smp_processor_id())
kvmppc_ipi_thread(cpu);
}
@@ -1835,12 +1843,12 @@ static void kvmppc_wait_for_nap(void)
for (loops = 0; loops < 1000000; ++loops) {
/*
* Check if all threads are finished.
- * We set the vcpu pointer when starting a thread
+ * We set the vcore pointer when starting a thread
* and the thread clears it when finished, so we look
- * for any threads that still have a non-NULL vcpu ptr.
+ * for any threads that still have a non-NULL vcore ptr.
*/
for (i = 1; i < threads_per_subcore; ++i)
- if (paca[cpu + i].kvm_hstate.kvm_vcpu)
+ if (paca[cpu + i].kvm_hstate.kvm_vcore)
break;
if (i == threads_per_subcore) {
HMT_medium();
@@ -1850,7 +1858,7 @@ static void kvmppc_wait_for_nap(void)
}
HMT_medium();
for (i = 1; i < threads_per_subcore; ++i)
- if (paca[cpu + i].kvm_hstate.kvm_vcpu)
+ if (paca[cpu + i].kvm_hstate.kvm_vcore)
pr_err("KVM: CPU %d seems to be stuck\n", cpu + i);
}
@@ -1965,17 +1973,55 @@ static void kvmppc_vcore_end_preempt(struct kvmppc_vcore *vc)
vc->vcore_state = VCORE_INACTIVE;
}
+/*
+ * This stores information about the virtual cores currently
+ * assigned to a physical core.
+ */
struct core_info {
+ int n_subcores;
+ int max_subcore_threads;
int total_threads;
- struct list_head vcs;
+ int subcore_threads[MAX_SUBCORES];
+ struct kvm *subcore_vm[MAX_SUBCORES];
+ struct list_head vcs[MAX_SUBCORES];
};
+/*
+ * This mapping means subcores 0 and 1 can use threads 0-3 and 4-7
+ * respectively in 2-way micro-threading (split-core) mode.
+ */
+static int subcore_thread_map[MAX_SUBCORES] = { 0, 4, 2, 6 };
+
static void init_core_info(struct core_info *cip, struct kvmppc_vcore *vc)
{
+ int sub;
+
memset(cip, 0, sizeof(*cip));
+ cip->n_subcores = 1;
+ cip->max_subcore_threads = vc->num_threads;
cip->total_threads = vc->num_threads;
- INIT_LIST_HEAD(&cip->vcs);
- list_add_tail(&vc->preempt_list, &cip->vcs);
+ cip->subcore_threads[0] = vc->num_threads;
+ cip->subcore_vm[0] = vc->kvm;
+ for (sub = 0; sub < MAX_SUBCORES; ++sub)
+ INIT_LIST_HEAD(&cip->vcs[sub]);
+ list_add_tail(&vc->preempt_list, &cip->vcs[0]);
+}
+
+static bool subcore_config_ok(int n_subcores, int n_threads)
+{
+ /* Can only dynamically split if unsplit to begin with */
+ if (n_subcores > 1 && threads_per_subcore < MAX_SMT_THREADS)
+ return false;
+ if (n_subcores > MAX_SUBCORES)
+ return false;
+ if (n_subcores > 1) {
+ if (!(dynamic_mt_modes & 2))
+ n_subcores = 4;
+ if (n_subcores > 2 && !(dynamic_mt_modes & 4))
+ return false;
+ }
+
+ return n_subcores * roundup_pow_of_two(n_threads) <= MAX_SMT_THREADS;
}
static void init_master_vcore(struct kvmppc_vcore *vc)
@@ -1988,15 +2034,113 @@ static void init_master_vcore(struct kvmppc_vcore *vc)
}
/*
- * Work out whether it is possible to piggyback the execute of
- * vcore *pvc onto the execution of the other vcores described in *cip.
+ * See if the existing subcores can be split into 3 (or fewer) subcores
+ * of at most two threads each, so we can fit in another vcore. This
+ * assumes there are at most two subcores and at most 6 threads in total.
*/
-static bool can_piggyback(struct kvmppc_vcore *pvc, struct core_info *cip,
- int target_threads)
+static bool can_split_piggybacked_subcores(struct core_info *cip)
+{
+ int sub, new_sub;
+ int large_sub = -1;
+ int thr;
+ int n_subcores = cip->n_subcores;
+ struct kvmppc_vcore *vc, *vcnext;
+ struct kvmppc_vcore *master_vc = NULL;
+
+ for (sub = 0; sub < cip->n_subcores; ++sub) {
+ if (cip->subcore_threads[sub] <= 2)
+ continue;
+ if (large_sub >= 0)
+ return false;
+ large_sub = sub;
+ vc = list_first_entry(&cip->vcs[sub], struct kvmppc_vcore,
+ preempt_list);
+ if (vc->num_threads > 2)
+ return false;
+ n_subcores += (cip->subcore_threads[sub] - 1) >> 1;
+ }
+ if (n_subcores > 3 || large_sub < 0)
+ return false;
+
+ /*
+ * Seems feasible, so go through and move vcores to new subcores.
+ * Note that when we have two or more vcores in one subcore,
+ * all those vcores must have only one thread each.
+ */
+ new_sub = cip->n_subcores;
+ thr = 0;
+ sub = large_sub;
+ list_for_each_entry_safe(vc, vcnext, &cip->vcs[sub], preempt_list) {
+ if (thr >= 2) {
+ list_del(&vc->preempt_list);
+ list_add_tail(&vc->preempt_list, &cip->vcs[new_sub]);
+ /* vc->num_threads must be 1 */
+ if (++cip->subcore_threads[new_sub] == 1) {
+ cip->subcore_vm[new_sub] = vc->kvm;
+ init_master_vcore(vc);
+ master_vc = vc;
+ ++cip->n_subcores;
+ } else {
+ vc->master_vcore = master_vc;
+ ++new_sub;
+ }
+ }
+ thr += vc->num_threads;
+ }
+ cip->subcore_threads[large_sub] = 2;
+ cip->max_subcore_threads = 2;
+
+ return true;
+}
+
+static bool can_dynamic_split(struct kvmppc_vcore *vc, struct core_info *cip)
+{
+ int n_threads = vc->num_threads;
+ int sub;
+
+ if (!cpu_has_feature(CPU_FTR_ARCH_207S))
+ return false;
+
+ if (n_threads < cip->max_subcore_threads)
+ n_threads = cip->max_subcore_threads;
+ if (subcore_config_ok(cip->n_subcores + 1, n_threads)) {
+ cip->max_subcore_threads = n_threads;
+ } else if (cip->n_subcores <= 2 && cip->total_threads <= 6 &&
+ vc->num_threads <= 2) {
+ /*
+ * We may be able to fit another subcore in by
+ * splitting an existing subcore with 3 or 4
+ * threads into two 2-thread subcores, or one
+ * with 5 or 6 threads into three subcores.
+ * We can only do this if those subcores have
+ * piggybacked virtual cores.
+ */
+ if (!can_split_piggybacked_subcores(cip))
+ return false;
+ } else {
+ return false;
+ }
+
+ sub = cip->n_subcores;
+ ++cip->n_subcores;
+ cip->total_threads += vc->num_threads;
+ cip->subcore_threads[sub] = vc->num_threads;
+ cip->subcore_vm[sub] = vc->kvm;
+ init_master_vcore(vc);
+ list_del(&vc->preempt_list);
+ list_add_tail(&vc->preempt_list, &cip->vcs[sub]);
+
+ return true;
+}
+
+static bool can_piggyback_subcore(struct kvmppc_vcore *pvc,
+ struct core_info *cip, int sub)
{
struct kvmppc_vcore *vc;
+ int n_thr;
- vc = list_first_entry(&cip->vcs, struct kvmppc_vcore, preempt_list);
+ vc = list_first_entry(&cip->vcs[sub], struct kvmppc_vcore,
+ preempt_list);
/* require same VM and same per-core reg values */
if (pvc->kvm != vc->kvm ||
@@ -2010,17 +2154,44 @@ static bool can_piggyback(struct kvmppc_vcore *pvc, struct core_info *cip,
(vc->num_threads > 1 || pvc->num_threads > 1))
return false;
- if (cip->total_threads + pvc->num_threads > target_threads)
- return false;
+ n_thr = cip->subcore_threads[sub] + pvc->num_threads;
+ if (n_thr > cip->max_subcore_threads) {
+ if (!subcore_config_ok(cip->n_subcores, n_thr))
+ return false;
+ cip->max_subcore_threads = n_thr;
+ }
cip->total_threads += pvc->num_threads;
+ cip->subcore_threads[sub] = n_thr;
pvc->master_vcore = vc;
list_del(&pvc->preempt_list);
- list_add_tail(&pvc->preempt_list, &cip->vcs);
+ list_add_tail(&pvc->preempt_list, &cip->vcs[sub]);
return true;
}
+/*
+ * Work out whether it is possible to piggyback the execution of
+ * vcore *pvc onto the execution of the other vcores described in *cip.
+ */
+static bool can_piggyback(struct kvmppc_vcore *pvc, struct core_info *cip,
+ int target_threads)
+{
+ int sub;
+
+ if (cip->total_threads + pvc->num_threads > target_threads)
+ return false;
+ for (sub = 0; sub < cip->n_subcores; ++sub)
+ if (cip->subcore_threads[sub] &&
+ can_piggyback_subcore(pvc, cip, sub))
+ return true;
+
+ if (can_dynamic_split(pvc, cip))
+ return true;
+
+ return false;
+}
+
static void prepare_threads(struct kvmppc_vcore *vc)
{
struct kvm_vcpu *vcpu, *vnext;
@@ -2135,6 +2306,11 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
int srcu_idx;
struct core_info core_info;
struct kvmppc_vcore *pvc, *vcnext;
+ struct kvm_split_mode split_info, *sip;
+ int split, subcore_size, active;
+ int sub;
+ bool thr0_done;
+ unsigned long cmd_bit, stat_bit;
int pcpu, thr;
int target_threads;
@@ -2182,29 +2358,100 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
if (vc->num_threads < target_threads)
collect_piggybacks(&core_info, target_threads);
- thr = 0;
- list_for_each_entry(pvc, &core_info.vcs, preempt_list) {
- pvc->pcpu = pcpu + thr;
- list_for_each_entry(vcpu, &pvc->runnable_threads,
- arch.run_list) {
- kvmppc_start_thread(vcpu);
- kvmppc_create_dtl_entry(vcpu, pvc);
- trace_kvm_guest_enter(vcpu);
+ /* Decide on micro-threading (split-core) mode */
+ subcore_size = threads_per_subcore;
+ cmd_bit = stat_bit = 0;
+ split = core_info.n_subcores;
+ sip = NULL;
+ if (split > 1) {
+ /* threads_per_subcore must be MAX_SMT_THREADS (8) here */
+ if (split == 2 && (dynamic_mt_modes & 2)) {
+ cmd_bit = HID0_POWER8_1TO2LPAR;
+ stat_bit = HID0_POWER8_2LPARMODE;
+ } else {
+ split = 4;
+ cmd_bit = HID0_POWER8_1TO4LPAR;
+ stat_bit = HID0_POWER8_4LPARMODE;
}
- thr += pvc->num_threads;
+ subcore_size = MAX_SMT_THREADS / split;
+ sip = &split_info;
+ memset(&split_info, 0, sizeof(split_info));
+ split_info.rpr = mfspr(SPRN_RPR);
+ split_info.pmmar = mfspr(SPRN_PMMAR);
+ split_info.ldbar = mfspr(SPRN_LDBAR);
+ split_info.subcore_size = subcore_size;
+ for (sub = 0; sub < core_info.n_subcores; ++sub)
+ split_info.master_vcs[sub] =
+ list_first_entry(&core_info.vcs[sub],
+ struct kvmppc_vcore, preempt_list);
+ /* order writes to split_info before kvm_split_mode pointer */
+ smp_wmb();
}
-
- /* Set this explicitly in case thread 0 doesn't have a vcpu */
- get_paca()->kvm_hstate.kvm_vcore = vc;
- get_paca()->kvm_hstate.ptid = 0;
+ pcpu = smp_processor_id();
+ for (thr = 0; thr < threads_per_subcore; ++thr)
+ paca[pcpu + thr].kvm_hstate.kvm_split_mode = sip;
+
+ /* Initiate micro-threading (split-core) if required */
+ if (cmd_bit) {
+ unsigned long hid0 = mfspr(SPRN_HID0);
+
+ hid0 |= cmd_bit | HID0_POWER8_DYNLPARDIS;
+ mb();
+ mtspr(SPRN_HID0, hid0);
+ isync();
+ for (;;) {
+ hid0 = mfspr(SPRN_HID0);
+ if (hid0 & stat_bit)
+ break;
+ cpu_relax();
+ }
+ split_info.do_nap = 1; /* ask secondaries to nap when done */
+ }
+
+ /* Start all the threads */
+ active = 0;
+ for (sub = 0; sub < core_info.n_subcores; ++sub) {
+ thr = subcore_thread_map[sub];
+ thr0_done = false;
+ active |= 1 << thr;
+ list_for_each_entry(pvc, &core_info.vcs[sub], preempt_list) {
+ pvc->pcpu = pcpu + thr;
+ list_for_each_entry(vcpu, &pvc->runnable_threads,
+ arch.run_list) {
+ kvmppc_start_thread(vcpu, pvc);
+ kvmppc_create_dtl_entry(vcpu, pvc);
+ trace_kvm_guest_enter(vcpu);
+ if (!vcpu->arch.ptid)
+ thr0_done = true;
+ active |= 1 << (thr + vcpu->arch.ptid);
+ }
+ /*
+ * We need to start the first thread of each subcore
+ * even if it doesn't have a vcpu.
+ */
+ if (pvc->master_vcore == pvc && !thr0_done)
+ kvmppc_start_thread(NULL, pvc);
+ thr += pvc->num_threads;
+ }
+ }
+ /*
+ * When doing micro-threading, poke the inactive threads as well.
+ * This gets them to the nap instruction after kvm_do_nap,
+ * which reduces the time taken to unsplit later.
+ */
+ if (split > 1)
+ for (thr = 1; thr < threads_per_subcore; ++thr)
+ if (!(active & (1 << thr)))
+ kvmppc_ipi_thread(pcpu + thr);
vc->vcore_state = VCORE_RUNNING;
preempt_disable();
trace_kvmppc_run_core(vc, 0);
- list_for_each_entry(pvc, &core_info.vcs, preempt_list)
- spin_unlock(&pvc->lock);
+ for (sub = 0; sub < core_info.n_subcores; ++sub)
+ list_for_each_entry(pvc, &core_info.vcs[sub], preempt_list)
+ spin_unlock(&pvc->lock);
kvm_guest_enter();
@@ -2226,16 +2473,44 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
/* wait for secondary threads to finish writing their state to memory */
kvmppc_wait_for_nap();
- for (i = 0; i < threads_per_subcore; ++i)
- kvmppc_release_hwthread(vc->pcpu + i);
+
+ /* Return to whole-core mode if we split the core earlier */
+ if (split > 1) {
+ unsigned long hid0 = mfspr(SPRN_HID0);
+ unsigned long loops = 0;
+
+ hid0 &= ~HID0_POWER8_DYNLPARDIS;
+ stat_bit = HID0_POWER8_2LPARMODE | HID0_POWER8_4LPARMODE;
+ mb();
+ mtspr(SPRN_HID0, hid0);
+ isync();
+ for (;;) {
+ hid0 = mfspr(SPRN_HID0);
+ if (!(hid0 & stat_bit))
+ break;
+ cpu_relax();
+ ++loops;
+ }
+ split_info.do_nap = 0;
+ }
+
+ /* Let secondaries go back to the offline loop */
+ for (i = 0; i < threads_per_subcore; ++i) {
+ kvmppc_release_hwthread(pcpu + i);
+ if (sip && sip->napped[i])
+ kvmppc_ipi_thread(pcpu + i);
+ }
+
spin_unlock(&vc->lock);
/* make sure updates to secondary vcpu structs are visible now */
smp_mb();
kvm_guest_exit();
- list_for_each_entry_safe(pvc, vcnext, &core_info.vcs, preempt_list)
- post_guest_process(pvc, pvc == vc);
+ for (sub = 0; sub < core_info.n_subcores; ++sub)
+ list_for_each_entry_safe(pvc, vcnext, &core_info.vcs[sub],
+ preempt_list)
+ post_guest_process(pvc, pvc == vc);
spin_lock(&vc->lock);
preempt_enable();
@@ -2341,7 +2616,7 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
if (mvc->vcore_state == VCORE_RUNNING &&
!VCORE_IS_EXITING(mvc)) {
kvmppc_create_dtl_entry(vcpu, vc);
- kvmppc_start_thread(vcpu);
+ kvmppc_start_thread(vcpu, vc);
trace_kvm_guest_enter(vcpu);
}
spin_unlock(&mvc->lock);
@@ -2349,7 +2624,7 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
} else if (vc->vcore_state == VCORE_RUNNING &&
!VCORE_IS_EXITING(vc)) {
kvmppc_create_dtl_entry(vcpu, vc);
- kvmppc_start_thread(vcpu);
+ kvmppc_start_thread(vcpu, vc);
trace_kvm_guest_enter(vcpu);
} else if (vc->vcore_state == VCORE_SLEEPING) {
wake_up(&vc->wq);
@@ -239,7 +239,8 @@ void kvmhv_commence_exit(int trap)
{
struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
int ptid = local_paca->kvm_hstate.ptid;
- int me, ee;
+ struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode;
+ int me, ee, i;
/* Set our bit in the threads-exiting-guest map in the 0xff00
bits of vcore->entry_exit_map */
@@ -259,4 +260,26 @@ void kvmhv_commence_exit(int trap)
*/
if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER)
kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid));
+
+ /*
+ * If we are doing dynamic micro-threading, interrupt the other
+ * subcores to pull them out of their guests too.
+ */
+ if (!sip)
+ return;
+
+ for (i = 0; i < MAX_SUBCORES; ++i) {
+ vc = sip->master_vcs[i];
+ if (!vc)
+ break;
+ do {
+ ee = vc->entry_exit_map;
+ /* Already asked to exit? */
+ if ((ee >> 8) != 0)
+ break;
+ } while (cmpxchg(&vc->entry_exit_map, ee,
+ ee | VCORE_EXIT_REQ) != ee);
+ if ((ee >> 8) == 0)
+ kvmhv_interrupt_vcore(vc, ee);
+ }
}
@@ -128,6 +128,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
subf r4, r4, r3
mtspr SPRN_DEC, r4
+ /* hwthread_req may have got set by cede or no vcpu, so clear it */
+ li r0, 0
+ stb r0, HSTATE_HWTHREAD_REQ(r13)
+
/*
* For external and machine check interrupts, we need
* to call the Linux handler to process the interrupt.
@@ -215,7 +219,6 @@ kvm_novcpu_wakeup:
ld r5, HSTATE_KVM_VCORE(r13)
li r0, 0
stb r0, HSTATE_NAPPING(r13)
- stb r0, HSTATE_HWTHREAD_REQ(r13)
/* check the wake reason */
bl kvmppc_check_wake_reason
@@ -315,10 +318,10 @@ kvm_start_guest:
cmpdi r3, 0
bge kvm_no_guest
- /* get vcpu pointer, NULL if we have no vcpu to run */
- ld r4,HSTATE_KVM_VCPU(r13)
- cmpdi r4,0
- /* if we have no vcpu to run, go back to sleep */
+ /* get vcore pointer, NULL if we have nothing to run */
+ ld r5,HSTATE_KVM_VCORE(r13)
+ cmpdi r5,0
+ /* if we have no vcore to run, go back to sleep */
beq kvm_no_guest
kvm_secondary_got_guest:
@@ -327,21 +330,42 @@ kvm_secondary_got_guest:
ld r6, PACA_DSCR_DEFAULT(r13)
std r6, HSTATE_DSCR(r13)
- /* Order load of vcore, ptid etc. after load of vcpu */
+ /* On thread 0 of a subcore, set HDEC to max */
+ lbz r4, HSTATE_PTID(r13)
+ cmpwi r4, 0
+ bne 63f
+ lis r6, 0x7fff
+ ori r6, r6, 0xffff
+ mtspr SPRN_HDEC, r6
+ /* and set per-LPAR registers, if doing dynamic micro-threading */
+ ld r6, HSTATE_SPLIT_MODE(r13)
+ cmpdi r6, 0
+ beq 63f
+ ld r0, KVM_SPLIT_RPR(r6)
+ mtspr SPRN_RPR, r0
+ ld r0, KVM_SPLIT_PMMAR(r6)
+ mtspr SPRN_PMMAR, r0
+ ld r0, KVM_SPLIT_LDBAR(r6)
+ mtspr SPRN_LDBAR, r0
+ isync
+63:
+ /* Order load of vcpu after load of vcore */
lwsync
+ ld r4, HSTATE_KVM_VCPU(r13)
bl kvmppc_hv_entry
/* Back from the guest, go back to nap */
- /* Clear our vcpu pointer so we don't come back in early */
+ /* Clear our vcpu and vcore pointers so we don't come back in early */
li r0, 0
+ std r0, HSTATE_KVM_VCPU(r13)
/*
- * Once we clear HSTATE_KVM_VCPU(r13), the code in
+ * Once we clear HSTATE_KVM_VCORE(r13), the code in
* kvmppc_run_core() is going to assume that all our vcpu
* state is visible in memory. This lwsync makes sure
* that that is true.
*/
lwsync
- std r0, HSTATE_KVM_VCPU(r13)
+ std r0, HSTATE_KVM_VCORE(r13)
/*
* At this point we have finished executing in the guest.
@@ -374,16 +398,63 @@ kvm_no_guest:
b power7_wakeup_loss
53: HMT_LOW
- ld r4, HSTATE_KVM_VCPU(r13)
- cmpdi r4, 0
+ ld r5, HSTATE_KVM_VCORE(r13)
+ cmpdi r5, 0
+ bne 60f
+ ld r3, HSTATE_SPLIT_MODE(r13)
+ cmpdi r3, 0
+ beq kvm_no_guest
+ lbz r0, KVM_SPLIT_DO_NAP(r3)
+ cmpwi r0, 0
beq kvm_no_guest
HMT_MEDIUM
+ b kvm_unsplit_nap
+60: HMT_MEDIUM
b kvm_secondary_got_guest
54: li r0, KVM_HWTHREAD_IN_KVM
stb r0, HSTATE_HWTHREAD_STATE(r13)
b kvm_no_guest
+/*
+ * Here the primary thread is trying to return the core to
+ * whole-core mode, so we need to nap.
+ */
+kvm_unsplit_nap:
+ /* clear any pending message */
+BEGIN_FTR_SECTION
+ lis r6, (PPC_DBELL_SERVER << (63-36))@h
+ PPC_MSGCLR(6)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+ /* Set kvm_split_mode.napped[tid] = 1 */
+ ld r3, HSTATE_SPLIT_MODE(r13)
+ li r0, 1
+ lhz r4, PACAPACAINDEX(r13)
+ clrldi r4, r4, 61 /* micro-threading => P8 => 8 threads/core */
+ addi r4, r4, KVM_SPLIT_NAPPED
+ stbx r0, r3, r4
+ /* Check the do_nap flag again after setting napped[] */
+ sync
+ lbz r0, KVM_SPLIT_DO_NAP(r3)
+ cmpwi r0, 0
+ beq 57f
+ li r3, (LPCR_PECEDH | LPCR_PECE0) >> 4
+ mfspr r4, SPRN_LPCR
+ rlwimi r4, r3, 4, (LPCR_PECEDP | LPCR_PECEDH | LPCR_PECE0 | LPCR_PECE1)
+ mtspr SPRN_LPCR, r4
+ isync
+ std r0, HSTATE_SCRATCH0(r13)
+ ptesync
+ ld r0, HSTATE_SCRATCH0(r13)
+1: cmpd r0, r0
+ bne 1b
+ nap
+ b .
+
+57: li r0, 0
+ stbx r0, r3, r4
+ b kvm_no_guest
+
/******************************************************************************
* *
* Entry code *
@@ -854,7 +925,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
cmpwi r0, 0
bne 21f
HMT_LOW
-20: lbz r0, VCORE_IN_GUEST(r5)
+20: lwz r3, VCORE_ENTRY_EXIT(r5)
+ cmpwi r3, 0x100
+ bge no_switch_exit
+ lbz r0, VCORE_IN_GUEST(r5)
cmpwi r0, 0
beq 20b
HMT_MEDIUM
@@ -985,9 +1059,13 @@ secondary_too_late:
#endif
11: b kvmhv_switch_to_host
+no_switch_exit:
+ HMT_MEDIUM
+ li r12, 0
+ b 12f
hdec_soon:
li r12, BOOK3S_INTERRUPT_HV_DECREMENTER
- stw r12, VCPU_TRAP(r4)
+12: stw r12, VCPU_TRAP(r4)
mr r9, r4
#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
addi r3, r4, VCPU_TB_RMEXIT
@@ -1545,12 +1623,17 @@ kvmhv_switch_to_host:
/* Primary thread waits for all the secondaries to exit guest */
15: lwz r3,VCORE_ENTRY_EXIT(r5)
- srwi r0,r3,8
+ rlwinm r0,r3,32-8,0xff
clrldi r3,r3,56
cmpw r3,r0
bne 15b
isync
+ /* Did we actually switch to the guest at all? */
+ lbz r6, VCORE_IN_GUEST(r5)
+ cmpwi r6, 0
+ beq 19f
+
/* Primary thread switches back to host partition */
ld r6,KVM_HOST_SDR1(r4)
lwz r7,KVM_HOST_LPID(r4)
@@ -1594,7 +1677,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
18:
/* Signal secondary CPUs to continue */
stb r0,VCORE_IN_GUEST(r5)
- lis r8,0x7fff /* MAX_INT@h */
+19: lis r8,0x7fff /* MAX_INT@h */
mtspr SPRN_HDEC,r8
16: ld r8,KVM_HOST_LPCR(r4)