| Message ID | 20170627060756.j6aabc5opui7knf3@oak.ozlabs.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jun 27, 2017 at 04:07:56PM +1000, Paul Mackerras wrote: > Since commit b009031f74da ("KVM: PPC: Book3S HV: Take out virtual > core piggybacking code", 2016-09-15), we only have at most one > vcore per subcore. Previously, the fact that there might be more > than one vcore per subcore meant that we had the notion of a > "master vcore", which was the vcore that controlled thread 0 of > the subcore. We also needed a list per subcore in the core_info > struct to record which vcores belonged to each subcore. Now that > there can only be one vcore in the subcore, we can replace the > list with a simple pointer and get rid of the notion of the > master vcore (and in fact treat every vcore as a master vcore). > > We can also get rid of the subcore_vm[] field in the core_info > struct since it is never read. > > Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> > --- > arch/powerpc/include/asm/kvm_book3s.h | 1 - > arch/powerpc/include/asm/kvm_book3s_asm.h | 2 +- > arch/powerpc/kvm/book3s_hv.c | 88 +++++++++++++------------------ > arch/powerpc/kvm/book3s_hv_builtin.c | 2 +- > 4 files changed, 39 insertions(+), 54 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h > index 2bf35017ffc0..b8d5b8e35244 100644 > --- a/arch/powerpc/include/asm/kvm_book3s.h > +++ b/arch/powerpc/include/asm/kvm_book3s.h > @@ -86,7 +86,6 @@ struct kvmppc_vcore { > u16 last_cpu; > u8 vcore_state; > u8 in_guest; > - struct kvmppc_vcore *master_vcore; > struct kvm_vcpu *runnable_threads[MAX_SMT_THREADS]; > struct list_head preempt_list; > spinlock_t lock; > diff --git a/arch/powerpc/include/asm/kvm_book3s_asm.h b/arch/powerpc/include/asm/kvm_book3s_asm.h > index b148496ffe36..7cea76f11c26 100644 > --- a/arch/powerpc/include/asm/kvm_book3s_asm.h > +++ b/arch/powerpc/include/asm/kvm_book3s_asm.h > @@ -81,7 +81,7 @@ struct kvm_split_mode { > u8 subcore_size; > u8 do_nap; > u8 napped[MAX_SMT_THREADS]; > - struct kvmppc_vcore *master_vcs[MAX_SUBCORES]; > + struct kvmppc_vcore *vc[MAX_SUBCORES]; > }; > > /* > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c > index c4ada89be658..03d6c7f9b547 100644 > --- a/arch/powerpc/kvm/book3s_hv.c > +++ b/arch/powerpc/kvm/book3s_hv.c > @@ -2171,7 +2171,6 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc) > { > int cpu; > struct paca_struct *tpaca; > - struct kvmppc_vcore *mvc = vc->master_vcore; > struct kvm *kvm = vc->kvm; > > cpu = vc->pcpu; > @@ -2181,7 +2180,7 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc) > vcpu->arch.timer_running = 0; > } > cpu += vcpu->arch.ptid; > - vcpu->cpu = mvc->pcpu; > + vcpu->cpu = vc->pcpu; > vcpu->arch.thread_cpu = cpu; > > /* > @@ -2207,10 +2206,10 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc) > } > tpaca = &paca[cpu]; > tpaca->kvm_hstate.kvm_vcpu = vcpu; > - tpaca->kvm_hstate.ptid = cpu - mvc->pcpu; > + tpaca->kvm_hstate.ptid = cpu - vc->pcpu; > /* Order stores to hstate.kvm_vcpu etc. before store to kvm_vcore */ > smp_wmb(); > - tpaca->kvm_hstate.kvm_vcore = mvc; > + tpaca->kvm_hstate.kvm_vcore = vc; > if (cpu != smp_processor_id()) > kvmppc_ipi_thread(cpu); > } > @@ -2339,8 +2338,7 @@ struct core_info { > int max_subcore_threads; > int total_threads; > int subcore_threads[MAX_SUBCORES]; > - struct kvm *subcore_vm[MAX_SUBCORES]; > - struct list_head vcs[MAX_SUBCORES]; > + struct kvmppc_vcore *vc[MAX_SUBCORES]; > }; > > /* > @@ -2351,17 +2349,12 @@ 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; > 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]); > + cip->vc[0] = vc; > } > > static bool subcore_config_ok(int n_subcores, int n_threads) > @@ -2381,9 +2374,8 @@ static bool subcore_config_ok(int n_subcores, int n_threads) > return n_subcores * roundup_pow_of_two(n_threads) <= MAX_SMT_THREADS; > } > > -static void init_master_vcore(struct kvmppc_vcore *vc) > +static void init_vcore_to_run(struct kvmppc_vcore *vc) > { > - vc->master_vcore = vc; > vc->entry_exit_map = 0; > vc->in_guest = 0; > vc->napping_threads = 0; > @@ -2408,9 +2400,9 @@ static bool can_dynamic_split(struct kvmppc_vcore *vc, struct core_info *cip) > ++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_move_tail(&vc->preempt_list, &cip->vcs[sub]); > + cip->vc[sub] = vc; > + init_vcore_to_run(vc); > + list_del_init(&vc->preempt_list); > > return true; > } > @@ -2515,7 +2507,6 @@ static void post_guest_process(struct kvmppc_vcore *vc, bool is_master) > wake_up(&vcpu->arch.cpu_run); > } > } > - list_del_init(&vc->preempt_list); > if (!is_master) { > if (still_running > 0) { > kvmppc_vcore_preempt(vc); > @@ -2587,7 +2578,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) > int i; > int srcu_idx; > struct core_info core_info; > - struct kvmppc_vcore *pvc, *vcnext; > + struct kvmppc_vcore *pvc; > struct kvm_split_mode split_info, *sip; > int split, subcore_size, active; > int sub; > @@ -2610,7 +2601,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) > /* > * Initialize *vc. > */ > - init_master_vcore(vc); > + init_vcore_to_run(vc); > vc->preempt_tb = TB_NIL; > > /* > @@ -2670,9 +2661,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) > 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); > + split_info.vc[sub] = core_info.vc[sub]; > /* order writes to split_info before kvm_split_mode pointer */ > smp_wmb(); > } > @@ -2704,24 +2693,23 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) > 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; > - for_each_runnable_thread(i, vcpu, pvc) { > - 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; > + pvc = core_info.vc[sub]; > + pvc->pcpu = pcpu + thr; > + for_each_runnable_thread(i, vcpu, pvc) { > + 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 (!thr0_done) > + kvmppc_start_thread(NULL, pvc); > + thr += pvc->num_threads; > } > > /* > @@ -2748,8 +2736,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) > trace_kvmppc_run_core(vc, 0); > > for (sub = 0; sub < core_info.n_subcores; ++sub) > - list_for_each_entry(pvc, &core_info.vcs[sub], preempt_list) > - spin_unlock(&pvc->lock); > + spin_unlock(&core_info.vc[sub]->lock); > > guest_enter(); > > @@ -2802,10 +2789,10 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) > smp_mb(); > guest_exit(); > > - 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); > + for (sub = 0; sub < core_info.n_subcores; ++sub) { > + pvc = core_info.vc[sub]; > + post_guest_process(pvc, pvc == vc); > + } > > spin_lock(&vc->lock); > preempt_enable(); > @@ -3026,15 +3013,14 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) > */ > if (!signal_pending(current)) { > if (vc->vcore_state == VCORE_PIGGYBACK) { > - struct kvmppc_vcore *mvc = vc->master_vcore; > - if (spin_trylock(&mvc->lock)) { > - if (mvc->vcore_state == VCORE_RUNNING && > - !VCORE_IS_EXITING(mvc)) { > + if (spin_trylock(&vc->lock)) { > + if (vc->vcore_state == VCORE_RUNNING && > + !VCORE_IS_EXITING(vc)) { > kvmppc_create_dtl_entry(vcpu, vc); > kvmppc_start_thread(vcpu, vc); > trace_kvm_guest_enter(vcpu); > } > - spin_unlock(&mvc->lock); > + spin_unlock(&vc->lock); > } > } else if (vc->vcore_state == VCORE_RUNNING && > !VCORE_IS_EXITING(vc)) { > diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c > index ee4c2558c305..90644db9d38e 100644 > --- a/arch/powerpc/kvm/book3s_hv_builtin.c > +++ b/arch/powerpc/kvm/book3s_hv_builtin.c > @@ -307,7 +307,7 @@ void kvmhv_commence_exit(int trap) > return; > > for (i = 0; i < MAX_SUBCORES; ++i) { > - vc = sip->master_vcs[i]; > + vc = sip->vc[i]; > if (!vc) > break; > do {
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index 2bf35017ffc0..b8d5b8e35244 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -86,7 +86,6 @@ struct kvmppc_vcore { u16 last_cpu; u8 vcore_state; u8 in_guest; - struct kvmppc_vcore *master_vcore; struct kvm_vcpu *runnable_threads[MAX_SMT_THREADS]; struct list_head preempt_list; spinlock_t lock; diff --git a/arch/powerpc/include/asm/kvm_book3s_asm.h b/arch/powerpc/include/asm/kvm_book3s_asm.h index b148496ffe36..7cea76f11c26 100644 --- a/arch/powerpc/include/asm/kvm_book3s_asm.h +++ b/arch/powerpc/include/asm/kvm_book3s_asm.h @@ -81,7 +81,7 @@ struct kvm_split_mode { u8 subcore_size; u8 do_nap; u8 napped[MAX_SMT_THREADS]; - struct kvmppc_vcore *master_vcs[MAX_SUBCORES]; + struct kvmppc_vcore *vc[MAX_SUBCORES]; }; /* diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index c4ada89be658..03d6c7f9b547 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2171,7 +2171,6 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc) { int cpu; struct paca_struct *tpaca; - struct kvmppc_vcore *mvc = vc->master_vcore; struct kvm *kvm = vc->kvm; cpu = vc->pcpu; @@ -2181,7 +2180,7 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc) vcpu->arch.timer_running = 0; } cpu += vcpu->arch.ptid; - vcpu->cpu = mvc->pcpu; + vcpu->cpu = vc->pcpu; vcpu->arch.thread_cpu = cpu; /* @@ -2207,10 +2206,10 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu, struct kvmppc_vcore *vc) } tpaca = &paca[cpu]; tpaca->kvm_hstate.kvm_vcpu = vcpu; - tpaca->kvm_hstate.ptid = cpu - mvc->pcpu; + tpaca->kvm_hstate.ptid = cpu - vc->pcpu; /* Order stores to hstate.kvm_vcpu etc. before store to kvm_vcore */ smp_wmb(); - tpaca->kvm_hstate.kvm_vcore = mvc; + tpaca->kvm_hstate.kvm_vcore = vc; if (cpu != smp_processor_id()) kvmppc_ipi_thread(cpu); } @@ -2339,8 +2338,7 @@ struct core_info { int max_subcore_threads; int total_threads; int subcore_threads[MAX_SUBCORES]; - struct kvm *subcore_vm[MAX_SUBCORES]; - struct list_head vcs[MAX_SUBCORES]; + struct kvmppc_vcore *vc[MAX_SUBCORES]; }; /* @@ -2351,17 +2349,12 @@ 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; 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]); + cip->vc[0] = vc; } static bool subcore_config_ok(int n_subcores, int n_threads) @@ -2381,9 +2374,8 @@ static bool subcore_config_ok(int n_subcores, int n_threads) return n_subcores * roundup_pow_of_two(n_threads) <= MAX_SMT_THREADS; } -static void init_master_vcore(struct kvmppc_vcore *vc) +static void init_vcore_to_run(struct kvmppc_vcore *vc) { - vc->master_vcore = vc; vc->entry_exit_map = 0; vc->in_guest = 0; vc->napping_threads = 0; @@ -2408,9 +2400,9 @@ static bool can_dynamic_split(struct kvmppc_vcore *vc, struct core_info *cip) ++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_move_tail(&vc->preempt_list, &cip->vcs[sub]); + cip->vc[sub] = vc; + init_vcore_to_run(vc); + list_del_init(&vc->preempt_list); return true; } @@ -2515,7 +2507,6 @@ static void post_guest_process(struct kvmppc_vcore *vc, bool is_master) wake_up(&vcpu->arch.cpu_run); } } - list_del_init(&vc->preempt_list); if (!is_master) { if (still_running > 0) { kvmppc_vcore_preempt(vc); @@ -2587,7 +2578,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) int i; int srcu_idx; struct core_info core_info; - struct kvmppc_vcore *pvc, *vcnext; + struct kvmppc_vcore *pvc; struct kvm_split_mode split_info, *sip; int split, subcore_size, active; int sub; @@ -2610,7 +2601,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) /* * Initialize *vc. */ - init_master_vcore(vc); + init_vcore_to_run(vc); vc->preempt_tb = TB_NIL; /* @@ -2670,9 +2661,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) 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); + split_info.vc[sub] = core_info.vc[sub]; /* order writes to split_info before kvm_split_mode pointer */ smp_wmb(); } @@ -2704,24 +2693,23 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) 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; - for_each_runnable_thread(i, vcpu, pvc) { - 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; + pvc = core_info.vc[sub]; + pvc->pcpu = pcpu + thr; + for_each_runnable_thread(i, vcpu, pvc) { + 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 (!thr0_done) + kvmppc_start_thread(NULL, pvc); + thr += pvc->num_threads; } /* @@ -2748,8 +2736,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) trace_kvmppc_run_core(vc, 0); for (sub = 0; sub < core_info.n_subcores; ++sub) - list_for_each_entry(pvc, &core_info.vcs[sub], preempt_list) - spin_unlock(&pvc->lock); + spin_unlock(&core_info.vc[sub]->lock); guest_enter(); @@ -2802,10 +2789,10 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) smp_mb(); guest_exit(); - 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); + for (sub = 0; sub < core_info.n_subcores; ++sub) { + pvc = core_info.vc[sub]; + post_guest_process(pvc, pvc == vc); + } spin_lock(&vc->lock); preempt_enable(); @@ -3026,15 +3013,14 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) */ if (!signal_pending(current)) { if (vc->vcore_state == VCORE_PIGGYBACK) { - struct kvmppc_vcore *mvc = vc->master_vcore; - if (spin_trylock(&mvc->lock)) { - if (mvc->vcore_state == VCORE_RUNNING && - !VCORE_IS_EXITING(mvc)) { + if (spin_trylock(&vc->lock)) { + if (vc->vcore_state == VCORE_RUNNING && + !VCORE_IS_EXITING(vc)) { kvmppc_create_dtl_entry(vcpu, vc); kvmppc_start_thread(vcpu, vc); trace_kvm_guest_enter(vcpu); } - spin_unlock(&mvc->lock); + spin_unlock(&vc->lock); } } else if (vc->vcore_state == VCORE_RUNNING && !VCORE_IS_EXITING(vc)) { diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index ee4c2558c305..90644db9d38e 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -307,7 +307,7 @@ void kvmhv_commence_exit(int trap) return; for (i = 0; i < MAX_SUBCORES; ++i) { - vc = sip->master_vcs[i]; + vc = sip->vc[i]; if (!vc) break; do {
Since commit b009031f74da ("KVM: PPC: Book3S HV: Take out virtual core piggybacking code", 2016-09-15), we only have at most one vcore per subcore. Previously, the fact that there might be more than one vcore per subcore meant that we had the notion of a "master vcore", which was the vcore that controlled thread 0 of the subcore. We also needed a list per subcore in the core_info struct to record which vcores belonged to each subcore. Now that there can only be one vcore in the subcore, we can replace the list with a simple pointer and get rid of the notion of the master vcore (and in fact treat every vcore as a master vcore). We can also get rid of the subcore_vm[] field in the core_info struct since it is never read. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> --- arch/powerpc/include/asm/kvm_book3s.h | 1 - arch/powerpc/include/asm/kvm_book3s_asm.h | 2 +- arch/powerpc/kvm/book3s_hv.c | 88 +++++++++++++------------------ arch/powerpc/kvm/book3s_hv_builtin.c | 2 +- 4 files changed, 39 insertions(+), 54 deletions(-)