Pranith Kumar <bobby.pr...@gmail.com> writes: > Alex Bennée writes: > >> From: Jan Kiszka <jan.kis...@siemens.com> >> >> This finally allows TCG to benefit from the iothread introduction: Drop >> the global mutex while running pure TCG CPU code. Reacquire the lock >> when entering MMIO or PIO emulation, or when leaving the TCG loop. >> >> We have to revert a few optimization for the current TCG threading >> model, namely kicking the TCG thread in qemu_mutex_lock_iothread and not >> kicking it in qemu_cpu_kick. We also need to disable RAM block >> reordering until we have a more efficient locking mechanism at hand. >> >> Still, a Linux x86 UP guest and my Musicpal ARM model boot fine here. >> These numbers demonstrate where we gain something: >> >> 20338 jan 20 0 331m 75m 6904 R 99 0.9 0:50.95 qemu-system-arm >> 20337 jan 20 0 331m 75m 6904 S 20 0.9 0:26.50 qemu-system-arm >> >> The guest CPU was fully loaded, but the iothread could still run mostly >> independent on a second core. Without the patch we don't get beyond >> >> 32206 jan 20 0 330m 73m 7036 R 82 0.9 1:06.00 qemu-system-arm >> 32204 jan 20 0 330m 73m 7036 S 21 0.9 0:17.03 qemu-system-arm >> >> We don't benefit significantly, though, when the guest is not fully >> loading a host CPU. >> >> Signed-off-by: Jan Kiszka <jan.kis...@siemens.com> >> Message-Id: <1439220437-23957-10-git-send-email-fred.kon...@greensocs.com> >> [FK: Rebase, fix qemu_devices_reset deadlock, rm address_space_* mutex] >> Signed-off-by: KONRAD Frederic <fred.kon...@greensocs.com> >> [EGC: fixed iothread lock for cpu-exec IRQ handling] >> Signed-off-by: Emilio G. Cota <c...@braap.org> >> [AJB: -smp single-threaded fix, clean commit msg, BQL fixes] >> Signed-off-by: Alex Bennée <alex.ben...@linaro.org> >> Reviewed-by: Richard Henderson <r...@twiddle.net> >> >> --- >> v8: >> - merged in BQL fixes for PPC target: ppc_set_irq >> - merged in BQL fixes for ARM target: ARM_CP_IO helpers >> - merged in BQL fixes for ARM target: arm_call_el_change_hook >> >> v5 (ajb, base patches): >> - added an assert to BQL unlock/lock functions instead of hanging >> - ensure all cpu->interrupt_requests *modifications* protected by BQL >> - add a re-read on cpu->interrupt_request for correctness >> - BQL fixes for: >> - assert BQL held for PPC hypercalls (emulate_spar_hypercall) >> - SCLP service calls on s390x >> - merge conflict with kick timer patch >> v4 (ajb, base patches): >> - protect cpu->interrupt updates with BQL >> - fix wording io_mem_notdirty calls >> - s/we/with/ >> v3 (ajb, base-patches): >> - stale iothread_unlocks removed (cpu_exit/resume_from_signal deals >> with it in the longjmp). >> - fix re-base conflicts >> v2 (ajb): >> - merge with tcg: grab iothread lock in cpu-exec interrupt handling >> - use existing fns for tracking lock state >> - lock iothread for mem_region >> - add assert on mem region modification >> - ensure smm_helper holds iothread >> - Add JK s-o-b >> - Fix-up FK s-o-b annotation >> v1 (ajb, base-patches): >> - SMP failure now fixed by previous commit >> >> Changes from Fred Konrad (mttcg-v7 via paolo): >> * Rebase on the current HEAD. >> * Fixes a deadlock in qemu_devices_reset(). >> * Remove the mutex in address_space_* >> --- >> cpu-exec.c | 20 ++++++++++++++++++-- >> cpus.c | 28 +++++----------------------- >> cputlb.c | 21 ++++++++++++++++++++- >> exec.c | 12 +++++++++--- >> hw/core/irq.c | 1 + >> hw/i386/kvmvapic.c | 4 ++-- >> hw/intc/arm_gicv3_cpuif.c | 3 +++ >> hw/ppc/ppc.c | 16 +++++++++++++++- >> hw/ppc/spapr.c | 3 +++ >> include/qom/cpu.h | 1 + >> memory.c | 2 ++ >> qom/cpu.c | 10 ++++++++++ >> target/arm/helper.c | 6 ++++++ >> target/arm/op_helper.c | 43 +++++++++++++++++++++++++++++++++++++++---- >> target/i386/smm_helper.c | 7 +++++++ >> target/s390x/misc_helper.c | 5 ++++- >> translate-all.c | 9 +++++++-- >> translate-common.c | 21 +++++++++++---------- >> 18 files changed, 163 insertions(+), 49 deletions(-) >> >> diff --git a/cpu-exec.c b/cpu-exec.c >> index f9e836c8dd..f42a128bdf 100644 >> --- a/cpu-exec.c >> +++ b/cpu-exec.c >> @@ -29,6 +29,7 @@ >> #include "qemu/rcu.h" >> #include "exec/tb-hash.h" >> #include "exec/log.h" >> +#include "qemu/main-loop.h" >> #if defined(TARGET_I386) && !defined(CONFIG_USER_ONLY) >> #include "hw/i386/apic.h" >> #endif >> @@ -388,8 +389,10 @@ static inline bool cpu_handle_halt(CPUState *cpu) >> if ((cpu->interrupt_request & CPU_INTERRUPT_POLL) >> && replay_interrupt()) { >> X86CPU *x86_cpu = X86_CPU(cpu); >> + qemu_mutex_lock_iothread(); >> apic_poll_irq(x86_cpu->apic_state); >> cpu_reset_interrupt(cpu, CPU_INTERRUPT_POLL); >> + qemu_mutex_unlock_iothread(); >> } >> #endif >> if (!cpu_has_work(cpu)) { >> @@ -443,7 +446,9 @@ static inline bool cpu_handle_exception(CPUState *cpu, >> int *ret) >> #else >> if (replay_exception()) { >> CPUClass *cc = CPU_GET_CLASS(cpu); >> + qemu_mutex_lock_iothread(); >> cc->do_interrupt(cpu); >> + qemu_mutex_unlock_iothread(); >> cpu->exception_index = -1; >> } else if (!replay_has_interrupt()) { >> /* give a chance to iothread in replay mode */ >> @@ -469,9 +474,11 @@ static inline void cpu_handle_interrupt(CPUState *cpu, >> TranslationBlock **last_tb) >> { >> CPUClass *cc = CPU_GET_CLASS(cpu); >> - int interrupt_request = cpu->interrupt_request; >> >> - if (unlikely(interrupt_request)) { >> + if (unlikely(atomic_read(&cpu->interrupt_request))) { >> + int interrupt_request; >> + qemu_mutex_lock_iothread(); >> + interrupt_request = cpu->interrupt_request; >> if (unlikely(cpu->singlestep_enabled & SSTEP_NOIRQ)) { >> /* Mask out external interrupts for this step. */ >> interrupt_request &= ~CPU_INTERRUPT_SSTEP_MASK; >> @@ -526,7 +533,12 @@ static inline void cpu_handle_interrupt(CPUState *cpu, >> the program flow was changed */ >> *last_tb = NULL; >> } >> + >> + /* If we exit via cpu_loop_exit/longjmp it is reset in cpu_exec */ >> + qemu_mutex_unlock_iothread(); >> } >> + >> + >> if (unlikely(atomic_read(&cpu->exit_request) || >> replay_has_interrupt())) { >> atomic_set(&cpu->exit_request, 0); >> cpu->exception_index = EXCP_INTERRUPT; >> @@ -656,8 +668,12 @@ int cpu_exec(CPUState *cpu) >> g_assert(cpu == current_cpu); >> g_assert(cc == CPU_GET_CLASS(cpu)); >> #endif /* buggy compiler */ >> + >> cpu->can_do_io = 1; >> tb_lock_reset(); >> + if (qemu_mutex_iothread_locked()) { >> + qemu_mutex_unlock_iothread(); >> + } >> } >> } /* for(;;) */ >> >> diff --git a/cpus.c b/cpus.c >> index 6d64199831..c48bc8d5b3 100644 >> --- a/cpus.c >> +++ b/cpus.c >> @@ -1026,8 +1026,6 @@ static void qemu_kvm_init_cpu_signals(CPUState *cpu) >> #endif /* _WIN32 */ >> >> static QemuMutex qemu_global_mutex; >> -static QemuCond qemu_io_proceeded_cond; >> -static unsigned iothread_requesting_mutex; >> >> static QemuThread io_thread; >> >> @@ -1041,7 +1039,6 @@ void qemu_init_cpu_loop(void) >> qemu_init_sigbus(); >> qemu_cond_init(&qemu_cpu_cond); >> qemu_cond_init(&qemu_pause_cond); >> - qemu_cond_init(&qemu_io_proceeded_cond); >> qemu_mutex_init(&qemu_global_mutex); >> >> qemu_thread_get_self(&io_thread); >> @@ -1084,10 +1081,6 @@ static void qemu_tcg_wait_io_event(CPUState *cpu) >> >> start_tcg_kick_timer(); >> >> - while (iothread_requesting_mutex) { >> - qemu_cond_wait(&qemu_io_proceeded_cond, &qemu_global_mutex); >> - } >> - >> CPU_FOREACH(cpu) { >> qemu_wait_io_event_common(cpu); >> } >> @@ -1248,9 +1241,11 @@ static int tcg_cpu_exec(CPUState *cpu) >> cpu->icount_decr.u16.low = decr; >> cpu->icount_extra = count; >> } >> + qemu_mutex_unlock_iothread(); >> cpu_exec_start(cpu); >> ret = cpu_exec(cpu); >> cpu_exec_end(cpu); >> + qemu_mutex_lock_iothread(); >> #ifdef CONFIG_PROFILER >> tcg_time += profile_getclock() - ti; >> #endif >> @@ -1478,27 +1473,14 @@ bool qemu_mutex_iothread_locked(void) >> >> void qemu_mutex_lock_iothread(void) >> { >> - atomic_inc(&iothread_requesting_mutex); >> - /* In the simple case there is no need to bump the VCPU thread out of >> - * TCG code execution. >> - */ >> - if (!tcg_enabled() || qemu_in_vcpu_thread() || >> - !first_cpu || !first_cpu->created) { >> - qemu_mutex_lock(&qemu_global_mutex); >> - atomic_dec(&iothread_requesting_mutex); >> - } else { >> - if (qemu_mutex_trylock(&qemu_global_mutex)) { >> - qemu_cpu_kick_rr_cpu(); >> - qemu_mutex_lock(&qemu_global_mutex); >> - } >> - atomic_dec(&iothread_requesting_mutex); >> - qemu_cond_broadcast(&qemu_io_proceeded_cond); >> - } >> + g_assert(!qemu_mutex_iothread_locked()); > > How about using tcg_debug_assert here... > >> + qemu_mutex_lock(&qemu_global_mutex); >> iothread_locked = true; >> } >> >> void qemu_mutex_unlock_iothread(void) >> { >> + g_assert(qemu_mutex_iothread_locked()); > > ... and here?
The iothread mutex is widely used in QEMU for bits other than TCG. In fact I think it was introduced when KVM support was merged. As such I don't want to remove these asserts from KVM mode. It does mean this patch is slowly accreteing fixes for the BQL being taken up by system emulation code though. > >> iothread_locked = false; >> qemu_mutex_unlock(&qemu_global_mutex); >> } >> diff --git a/cputlb.c b/cputlb.c >> index 6c39927455..1cc9d9da51 100644 >> --- a/cputlb.c >> +++ b/cputlb.c >> @@ -18,6 +18,7 @@ >> */ >> >> #include "qemu/osdep.h" >> +#include "qemu/main-loop.h" >> #include "cpu.h" >> #include "exec/exec-all.h" >> #include "exec/memory.h" >> @@ -495,6 +496,7 @@ static uint64_t io_readx(CPUArchState *env, >> CPUIOTLBEntry *iotlbentry, >> hwaddr physaddr = iotlbentry->addr; >> MemoryRegion *mr = iotlb_to_region(cpu, physaddr, iotlbentry->attrs); >> uint64_t val; >> + bool locked = false; >> >> physaddr = (physaddr & TARGET_PAGE_MASK) + addr; >> cpu->mem_io_pc = retaddr; >> @@ -503,7 +505,16 @@ static uint64_t io_readx(CPUArchState *env, >> CPUIOTLBEntry *iotlbentry, >> } >> >> cpu->mem_io_vaddr = addr; >> + >> + if (mr->global_locking) { >> + qemu_mutex_lock_iothread(); >> + locked = true; >> + } >> memory_region_dispatch_read(mr, physaddr, &val, size, >> iotlbentry->attrs); >> + if (locked) { >> + qemu_mutex_unlock_iothread(); >> + } >> + >> return val; >> } >> >> @@ -514,15 +525,23 @@ static void io_writex(CPUArchState *env, CPUIOTLBEntry >> *iotlbentry, >> CPUState *cpu = ENV_GET_CPU(env); >> hwaddr physaddr = iotlbentry->addr; >> MemoryRegion *mr = iotlb_to_region(cpu, physaddr, iotlbentry->attrs); >> + bool locked = false; >> >> physaddr = (physaddr & TARGET_PAGE_MASK) + addr; >> if (mr != &io_mem_rom && mr != &io_mem_notdirty && !cpu->can_do_io) { >> cpu_io_recompile(cpu, retaddr); >> } >> - > > I am not really opposed but, I like having this line.. not sure why > you are removing it? :) Over zealous whitespace trimming, I can put it back ;-) > >> cpu->mem_io_vaddr = addr; >> cpu->mem_io_pc = retaddr; >> + >> + if (mr->global_locking) { >> + qemu_mutex_lock_iothread(); >> + locked = true; >> + } >> memory_region_dispatch_write(mr, physaddr, val, size, >> iotlbentry->attrs); >> + if (locked) { >> + qemu_mutex_unlock_iothread(); >> + } >> } >> >> /* Return true if ADDR is present in the victim tlb, and has been copied >> diff --git a/exec.c b/exec.c >> index f2bed92b64..87cf0db91e 100644 >> --- a/exec.c >> +++ b/exec.c >> @@ -2133,9 +2133,9 @@ static void check_watchpoint(int offset, int len, >> MemTxAttrs attrs, int flags) >> } >> cpu->watchpoint_hit = wp; >> >> - /* The tb_lock will be reset when cpu_loop_exit or >> - * cpu_loop_exit_noexc longjmp back into the cpu_exec >> - * main loop. >> + /* Both tb_lock and iothread_mutex will be reset when >> + * cpu_loop_exit or cpu_loop_exit_noexc longjmp >> + * back into the cpu_exec main loop. >> */ >> tb_lock(); >> tb_check_watchpoint(cpu); >> @@ -2370,8 +2370,14 @@ static void io_mem_init(void) >> memory_region_init_io(&io_mem_rom, NULL, &unassigned_mem_ops, NULL, >> NULL, UINT64_MAX); >> memory_region_init_io(&io_mem_unassigned, NULL, &unassigned_mem_ops, >> NULL, >> NULL, UINT64_MAX); >> + >> + /* io_mem_notdirty calls tb_invalidate_phys_page_fast, >> + * which can be called without the iothread mutex. >> + */ >> memory_region_init_io(&io_mem_notdirty, NULL, ¬dirty_mem_ops, NULL, >> NULL, UINT64_MAX); >> + memory_region_clear_global_locking(&io_mem_notdirty); >> + >> memory_region_init_io(&io_mem_watch, NULL, &watch_mem_ops, NULL, >> NULL, UINT64_MAX); >> } >> diff --git a/hw/core/irq.c b/hw/core/irq.c >> index 49ff2e64fe..b98d1d69f5 100644 >> --- a/hw/core/irq.c >> +++ b/hw/core/irq.c >> @@ -22,6 +22,7 @@ >> * THE SOFTWARE. >> */ >> #include "qemu/osdep.h" >> +#include "qemu/main-loop.h" >> #include "qemu-common.h" >> #include "hw/irq.h" >> #include "qom/object.h" >> diff --git a/hw/i386/kvmvapic.c b/hw/i386/kvmvapic.c >> index 702e281dc8..b3c49b2c61 100644 >> --- a/hw/i386/kvmvapic.c >> +++ b/hw/i386/kvmvapic.c >> @@ -451,8 +451,8 @@ static void patch_instruction(VAPICROMState *s, X86CPU >> *cpu, target_ulong ip) >> resume_all_vcpus(); >> >> if (!kvm_enabled()) { >> - /* tb_lock will be reset when cpu_loop_exit_noexc longjmps >> - * back into the cpu_exec loop. */ >> + /* Both tb_lock and iothread_mutex will be reset when >> + * longjmps back into the cpu_exec loop. */ > > missing cpu_loop_exit_noexc? Well cpu_exec is the main loop, even if cpu_loop_exit_noexc is what takes you there. I'll see if I can make it clearer: /* Both tb_lock and iothread_mutex will be reset when cpu_loop_exit_noexc longjmps back into the cpu_exec loop */ > >> tb_lock(); >> tb_gen_code(cs, current_pc, current_cs_base, current_flags, 1); >> cpu_loop_exit_noexc(cs); >> diff --git a/hw/intc/arm_gicv3_cpuif.c b/hw/intc/arm_gicv3_cpuif.c >> index a9ee7fddf9..2624d8d909 100644 >> --- a/hw/intc/arm_gicv3_cpuif.c >> +++ b/hw/intc/arm_gicv3_cpuif.c >> @@ -14,6 +14,7 @@ >> >> #include "qemu/osdep.h" >> #include "qemu/bitops.h" >> +#include "qemu/main-loop.h" >> #include "trace.h" >> #include "gicv3_internal.h" >> #include "cpu.h" >> @@ -733,6 +734,8 @@ void gicv3_cpuif_update(GICv3CPUState *cs) >> ARMCPU *cpu = ARM_CPU(cs->cpu); >> CPUARMState *env = &cpu->env; >> >> + g_assert(qemu_mutex_iothread_locked()); >> + > > tcg_debug_assert()? Depends if KVM can use this for emulation as well (which I think it can). > >> trace_gicv3_cpuif_update(gicv3_redist_affid(cs), cs->hppi.irq, >> cs->hppi.grp, cs->hppi.prio); >> >> diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c >> index 8945869009..59c3faa6c8 100644 >> --- a/hw/ppc/ppc.c >> +++ b/hw/ppc/ppc.c >> @@ -62,7 +62,16 @@ void ppc_set_irq(PowerPCCPU *cpu, int n_IRQ, int level) >> { >> CPUState *cs = CPU(cpu); >> CPUPPCState *env = &cpu->env; >> - unsigned int old_pending = env->pending_interrupts; >> + unsigned int old_pending; >> + bool locked = false; >> + >> + /* We may already have the BQL if coming from the reset path */ >> + if (!qemu_mutex_iothread_locked()) { >> + locked = true; >> + qemu_mutex_lock_iothread(); >> + } >> + >> + old_pending = env->pending_interrupts; >> >> if (level) { >> env->pending_interrupts |= 1 << n_IRQ; >> @@ -80,9 +89,14 @@ void ppc_set_irq(PowerPCCPU *cpu, int n_IRQ, int level) >> #endif >> } >> >> + >> LOG_IRQ("%s: %p n_IRQ %d level %d => pending %08" PRIx32 >> "req %08x\n", __func__, env, n_IRQ, level, >> env->pending_interrupts, CPU(cpu)->interrupt_request); >> + >> + if (locked) { >> + qemu_mutex_unlock_iothread(); >> + } >> } >> >> /* PowerPC 6xx / 7xx internal IRQ controller */ >> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c >> index a642e663d4..745743d64b 100644 >> --- a/hw/ppc/spapr.c >> +++ b/hw/ppc/spapr.c >> @@ -1012,6 +1012,9 @@ static void emulate_spapr_hypercall(PowerPCCPU *cpu) >> { >> CPUPPCState *env = &cpu->env; >> >> + /* The TCG path should also be holding the BQL at this point */ >> + g_assert(qemu_mutex_iothread_locked()); >> + > > tcg_debug_assert()? > >> if (msr_pr) { >> hcall_dprintf("Hypercall made with MSR[PR]=1\n"); >> env->gpr[3] = H_PRIVILEGE; >> diff --git a/include/qom/cpu.h b/include/qom/cpu.h >> index 11db2015a4..1a06ae5938 100644 >> --- a/include/qom/cpu.h >> +++ b/include/qom/cpu.h >> @@ -325,6 +325,7 @@ struct CPUState { >> bool unplug; >> bool crash_occurred; >> bool exit_request; >> + /* updates protected by BQL */ >> uint32_t interrupt_request; >> int singlestep_enabled; >> int64_t icount_extra; >> diff --git a/memory.c b/memory.c >> index 2bfc37f65c..7d7b285e41 100644 >> --- a/memory.c >> +++ b/memory.c >> @@ -917,6 +917,8 @@ void memory_region_transaction_commit(void) >> AddressSpace *as; >> >> assert(memory_region_transaction_depth); >> + assert(qemu_mutex_iothread_locked()); >> + >> --memory_region_transaction_depth; >> if (!memory_region_transaction_depth) { >> if (memory_region_update_pending) { >> diff --git a/qom/cpu.c b/qom/cpu.c >> index 7f575879f6..bd77c05cd0 100644 >> --- a/qom/cpu.c >> +++ b/qom/cpu.c >> @@ -113,9 +113,19 @@ static void cpu_common_get_memory_mapping(CPUState *cpu, >> error_setg(errp, "Obtaining memory mappings is unsupported on this >> CPU."); >> } >> >> +/* Resetting the IRQ comes from across the code base so we take the >> + * BQL here if we need to. cpu_interrupt assumes it is held.*/ >> void cpu_reset_interrupt(CPUState *cpu, int mask) >> { >> + bool need_lock = !qemu_mutex_iothread_locked(); >> + >> + if (need_lock) { >> + qemu_mutex_lock_iothread(); >> + } >> cpu->interrupt_request &= ~mask; >> + if (need_lock) { >> + qemu_mutex_unlock_iothread(); >> + } >> } >> >> void cpu_exit(CPUState *cpu) >> diff --git a/target/arm/helper.c b/target/arm/helper.c >> index 7111c8cf18..84d789be93 100644 >> --- a/target/arm/helper.c >> +++ b/target/arm/helper.c >> @@ -6693,6 +6693,12 @@ void arm_cpu_do_interrupt(CPUState *cs) >> arm_cpu_do_interrupt_aarch32(cs); >> } >> >> + /* Hooks may change global state so BQL should be held, also the >> + * BQL needs to be held for any modification of >> + * cs->interrupt_request. >> + */ >> + g_assert(qemu_mutex_iothread_locked()); >> + >> arm_call_el_change_hook(cpu); >> >> if (!kvm_enabled()) { >> diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c >> index ba796d898e..e1a883c595 100644 >> --- a/target/arm/op_helper.c >> +++ b/target/arm/op_helper.c >> @@ -18,6 +18,7 @@ >> */ >> #include "qemu/osdep.h" >> #include "qemu/log.h" >> +#include "qemu/main-loop.h" >> #include "cpu.h" >> #include "exec/helper-proto.h" >> #include "internals.h" >> @@ -487,7 +488,9 @@ void HELPER(cpsr_write_eret)(CPUARMState *env, uint32_t >> val) >> */ >> env->regs[15] &= (env->thumb ? ~1 : ~3); >> >> + qemu_mutex_lock_iothread(); >> arm_call_el_change_hook(arm_env_get_cpu(env)); >> + qemu_mutex_unlock_iothread(); >> } >> >> /* Access to user mode registers from privileged modes. */ >> @@ -735,28 +738,58 @@ void HELPER(set_cp_reg)(CPUARMState *env, void *rip, >> uint32_t value) >> { >> const ARMCPRegInfo *ri = rip; >> >> - ri->writefn(env, ri, value); >> + if (ri->type & ARM_CP_IO) { >> + qemu_mutex_lock_iothread(); >> + ri->writefn(env, ri, value); >> + qemu_mutex_unlock_iothread(); >> + } else { >> + ri->writefn(env, ri, value); >> + } >> } >> >> uint32_t HELPER(get_cp_reg)(CPUARMState *env, void *rip) >> { >> const ARMCPRegInfo *ri = rip; >> + uint32_t res; >> >> - return ri->readfn(env, ri); >> + if (ri->type & ARM_CP_IO) { >> + qemu_mutex_lock_iothread(); >> + res = ri->readfn(env, ri); >> + qemu_mutex_unlock_iothread(); >> + } else { >> + res = ri->readfn(env, ri); >> + } >> + >> + return res; >> } >> >> void HELPER(set_cp_reg64)(CPUARMState *env, void *rip, uint64_t value) >> { >> const ARMCPRegInfo *ri = rip; >> >> - ri->writefn(env, ri, value); >> + if (ri->type & ARM_CP_IO) { >> + qemu_mutex_lock_iothread(); >> + ri->writefn(env, ri, value); >> + qemu_mutex_unlock_iothread(); >> + } else { >> + ri->writefn(env, ri, value); >> + } >> } >> >> uint64_t HELPER(get_cp_reg64)(CPUARMState *env, void *rip) >> { >> const ARMCPRegInfo *ri = rip; >> + uint64_t res; >> + >> + if (ri->type & ARM_CP_IO) { >> + qemu_mutex_lock_iothread(); >> + res = ri->readfn(env, ri); >> + qemu_mutex_unlock_iothread(); >> + } else { >> + res = ri->readfn(env, ri); >> + } >> >> - return ri->readfn(env, ri); >> + return res; >> } >> >> void HELPER(msr_i_pstate)(CPUARMState *env, uint32_t op, uint32_t imm) >> @@ -989,7 +1022,9 @@ void HELPER(exception_return)(CPUARMState *env) >> cur_el, new_el, env->pc); >> } >> >> + qemu_mutex_lock_iothread(); >> arm_call_el_change_hook(arm_env_get_cpu(env)); >> + qemu_mutex_unlock_iothread(); >> >> return; >> >> diff --git a/target/i386/smm_helper.c b/target/i386/smm_helper.c >> index 4dd6a2c544..f051a77c4a 100644 >> --- a/target/i386/smm_helper.c >> +++ b/target/i386/smm_helper.c >> @@ -18,6 +18,7 @@ >> */ >> >> #include "qemu/osdep.h" >> +#include "qemu/main-loop.h" >> #include "cpu.h" >> #include "exec/helper-proto.h" >> #include "exec/log.h" >> @@ -42,11 +43,14 @@ void helper_rsm(CPUX86State *env) >> #define SMM_REVISION_ID 0x00020000 >> #endif >> >> +/* Called with iothread lock taken */ >> void cpu_smm_update(X86CPU *cpu) >> { >> CPUX86State *env = &cpu->env; >> bool smm_enabled = (env->hflags & HF_SMM_MASK); >> >> + g_assert(qemu_mutex_iothread_locked()); >> + >> if (cpu->smram) { >> memory_region_set_enabled(cpu->smram, smm_enabled); >> } >> @@ -333,7 +337,10 @@ void helper_rsm(CPUX86State *env) >> } >> env->hflags2 &= ~HF2_SMM_INSIDE_NMI_MASK; >> env->hflags &= ~HF_SMM_MASK; >> + >> + qemu_mutex_lock_iothread(); >> cpu_smm_update(cpu); >> + qemu_mutex_unlock_iothread(); >> >> qemu_log_mask(CPU_LOG_INT, "SMM: after RSM\n"); >> log_cpu_state_mask(CPU_LOG_INT, CPU(cpu), CPU_DUMP_CCOP); >> diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c >> index c9604ea9c7..3cb942e8bb 100644 >> --- a/target/s390x/misc_helper.c >> +++ b/target/s390x/misc_helper.c >> @@ -25,6 +25,7 @@ >> #include "exec/helper-proto.h" >> #include "sysemu/kvm.h" >> #include "qemu/timer.h" >> +#include "qemu/main-loop.h" >> #include "exec/address-spaces.h" >> #ifdef CONFIG_KVM >> #include <linux/kvm.h> >> @@ -109,11 +110,13 @@ void program_interrupt(CPUS390XState *env, uint32_t >> code, int ilen) >> /* SCLP service call */ >> uint32_t HELPER(servc)(CPUS390XState *env, uint64_t r1, uint64_t r2) >> { >> + qemu_mutex_lock_iothread(); >> int r = sclp_service_call(env, r1, r2); >> if (r < 0) { >> program_interrupt(env, -r, 4); >> - return 0; >> + r = 0; >> } >> + qemu_mutex_unlock_iothread(); >> return r; >> } >> >> diff --git a/translate-all.c b/translate-all.c >> index 055436a676..41b36f04c6 100644 >> --- a/translate-all.c >> +++ b/translate-all.c >> @@ -55,6 +55,7 @@ >> #include "translate-all.h" >> #include "qemu/bitmap.h" >> #include "qemu/timer.h" >> +#include "qemu/main-loop.h" >> #include "exec/log.h" >> >> /* #define DEBUG_TB_INVALIDATE */ >> @@ -1521,7 +1522,7 @@ void tb_invalidate_phys_page_range(tb_page_addr_t >> start, tb_page_addr_t end, >> #ifdef CONFIG_SOFTMMU >> /* len must be <= 8 and start must be a multiple of len. >> * Called via softmmu_template.h when code areas are written to with >> - * tb_lock held. >> + * iothread mutex not held. >> */ >> void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) >> { > > Shouldn't this be both tb_lock and iothread mutex? > >> @@ -1723,7 +1724,10 @@ void tb_check_watchpoint(CPUState *cpu) >> >> #ifndef CONFIG_USER_ONLY >> /* in deterministic execution mode, instructions doing device I/Os >> - must be at the end of the TB */ >> + * must be at the end of the TB. >> + * >> + * Called by softmmu_template.h, with iothread mutex not held. >> + */ >> void cpu_io_recompile(CPUState *cpu, uintptr_t retaddr) >> { >> #if defined(TARGET_MIPS) || defined(TARGET_SH4) >> @@ -1935,6 +1939,7 @@ void dump_opcount_info(FILE *f, fprintf_function >> cpu_fprintf) >> >> void cpu_interrupt(CPUState *cpu, int mask) >> { >> + g_assert(qemu_mutex_iothread_locked()); >> cpu->interrupt_request |= mask; >> cpu->tcg_exit_req = 1; >> } >> diff --git a/translate-common.c b/translate-common.c >> index 5e989cdf70..d504dd0d33 100644 >> --- a/translate-common.c >> +++ b/translate-common.c >> @@ -21,6 +21,7 @@ >> #include "qemu-common.h" >> #include "qom/cpu.h" >> #include "sysemu/cpus.h" >> +#include "qemu/main-loop.h" >> >> uintptr_t qemu_real_host_page_size; >> intptr_t qemu_real_host_page_mask; >> @@ -30,6 +31,7 @@ intptr_t qemu_real_host_page_mask; >> static void tcg_handle_interrupt(CPUState *cpu, int mask) >> { >> int old_mask; >> + g_assert(qemu_mutex_iothread_locked()); >> >> old_mask = cpu->interrupt_request; >> cpu->interrupt_request |= mask; >> @@ -40,17 +42,16 @@ static void tcg_handle_interrupt(CPUState *cpu, int mask) >> */ >> if (!qemu_cpu_is_self(cpu)) { >> qemu_cpu_kick(cpu); >> - return; >> - } >> - >> - if (use_icount) { >> - cpu->icount_decr.u16.high = 0xffff; >> - if (!cpu->can_do_io >> - && (mask & ~old_mask) != 0) { >> - cpu_abort(cpu, "Raised interrupt while not in I/O function"); >> - } >> } else { >> - cpu->tcg_exit_req = 1; >> + if (use_icount) { >> + cpu->icount_decr.u16.high = 0xffff; >> + if (!cpu->can_do_io >> + && (mask & ~old_mask) != 0) { >> + cpu_abort(cpu, "Raised interrupt while not in I/O >> function"); >> + } >> + } else { >> + cpu->tcg_exit_req = 1; >> + } >> } >> } > > Reviewed-by: Pranith Kumar <bobby.pr...@gmail.com> Thanks. -- Alex Bennée