Precompute the initial tb->cflags value for a cpu from its cluster and the number of cpus live in the system. This avoids having to compute this constant data every time we look up a TB.
Signed-off-by: Richard Henderson <[email protected]> --- Based-on: <[email protected]> ("Experimenting with tb-lookup tweaks") --- accel/tcg/tcg-accel-ops.h | 1 + include/exec/exec-all.h | 5 +---- include/hw/core/cpu.h | 2 ++ accel/tcg/cpu-exec.c | 3 --- accel/tcg/tcg-accel-ops-mttcg.c | 3 +-- accel/tcg/tcg-accel-ops-rr.c | 2 +- accel/tcg/tcg-accel-ops.c | 10 ++++++++++ accel/tcg/translate-all.c | 1 - linux-user/main.c | 1 + linux-user/sh4/signal.c | 2 +- linux-user/syscall.c | 18 ++++++++++-------- 11 files changed, 28 insertions(+), 20 deletions(-) diff --git a/accel/tcg/tcg-accel-ops.h b/accel/tcg/tcg-accel-ops.h index 48130006de..656c922a67 100644 --- a/accel/tcg/tcg-accel-ops.h +++ b/accel/tcg/tcg-accel-ops.h @@ -17,5 +17,6 @@ void tcg_cpus_destroy(CPUState *cpu); int tcg_cpus_exec(CPUState *cpu); void tcg_handle_interrupt(CPUState *cpu, int mask); +void tcg_set_cpus_cflags(uint32_t cflags_base); #endif /* TCG_CPUS_H */ diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h index 75f8c3981a..074d88f99a 100644 --- a/include/exec/exec-all.h +++ b/include/exec/exec-all.h @@ -510,8 +510,6 @@ struct TranslationBlock { uintptr_t jmp_dest[2]; }; -extern bool parallel_cpus; - /* Hide the qatomic_read to make code a little easier on the eyes */ static inline uint32_t tb_cflags(const TranslationBlock *tb) { @@ -521,8 +519,7 @@ static inline uint32_t tb_cflags(const TranslationBlock *tb) /* current cflags for hashing/comparison */ static inline uint32_t curr_cflags(CPUState *cpu) { - uint32_t cflags = deposit32(0, CF_CLUSTER_SHIFT, 8, cpu->cluster_index); - cflags |= parallel_cpus ? CF_PARALLEL : 0; + uint32_t cflags = cpu->cflags_base; cflags |= icount_enabled() ? CF_USE_ICOUNT : 0; return cflags; } diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h index c005d3dc2d..5fd397f37d 100644 --- a/include/hw/core/cpu.h +++ b/include/hw/core/cpu.h @@ -282,6 +282,7 @@ struct qemu_work_item; * to a cluster this will be UNASSIGNED_CLUSTER_INDEX; otherwise it will * be the same as the cluster-id property of the CPU object's TYPE_CPU_CLUSTER * QOM parent. + * @cflags_base: Precompute @cluster_index and #CF_PARALLEL for this cpu. * @nr_cores: Number of cores within this CPU package. * @nr_threads: Number of threads within this CPU. * @running: #true if CPU is currently running (lockless). @@ -412,6 +413,7 @@ struct CPUState { /* TODO Move common fields from CPUArchState here. */ int cpu_index; int cluster_index; + uint32_t cflags_base; uint32_t halted; uint32_t can_do_io; int32_t exception_index; diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index 931da96c2b..bdfa036ac8 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -267,8 +267,6 @@ void cpu_exec_step_atomic(CPUState *cpu) mmap_unlock(); } - /* Since we got here, we know that parallel_cpus must be true. */ - parallel_cpus = false; cpu_exec_enter(cpu); /* execute the generated code */ trace_exec_tb(tb, pc); @@ -296,7 +294,6 @@ void cpu_exec_step_atomic(CPUState *cpu) * the execution. */ g_assert(cpu_in_exclusive_context(cpu)); - parallel_cpus = true; cpu->running = false; end_exclusive(); } diff --git a/accel/tcg/tcg-accel-ops-mttcg.c b/accel/tcg/tcg-accel-ops-mttcg.c index 42973fb062..6676e05182 100644 --- a/accel/tcg/tcg-accel-ops-mttcg.c +++ b/accel/tcg/tcg-accel-ops-mttcg.c @@ -114,8 +114,7 @@ void mttcg_start_vcpu_thread(CPUState *cpu) char thread_name[VCPU_THREAD_NAME_SIZE]; g_assert(tcg_enabled()); - - parallel_cpus = (current_machine->smp.max_cpus > 1); + tcg_set_cpus_cflags(current_machine->smp.max_cpus > 1 ? CF_PARALLEL : 0); cpu->thread = g_malloc0(sizeof(QemuThread)); cpu->halt_cond = g_malloc0(sizeof(QemuCond)); diff --git a/accel/tcg/tcg-accel-ops-rr.c b/accel/tcg/tcg-accel-ops-rr.c index 4a66055e0d..c10868f736 100644 --- a/accel/tcg/tcg-accel-ops-rr.c +++ b/accel/tcg/tcg-accel-ops-rr.c @@ -269,7 +269,7 @@ void rr_start_vcpu_thread(CPUState *cpu) static QemuThread *single_tcg_cpu_thread; g_assert(tcg_enabled()); - parallel_cpus = false; + tcg_set_cpus_cflags(0); if (!single_tcg_cpu_thread) { cpu->thread = g_malloc0(sizeof(QemuThread)); diff --git a/accel/tcg/tcg-accel-ops.c b/accel/tcg/tcg-accel-ops.c index 6144d9df87..6bf260acf0 100644 --- a/accel/tcg/tcg-accel-ops.c +++ b/accel/tcg/tcg-accel-ops.c @@ -41,6 +41,16 @@ /* common functionality among all TCG variants */ +void tcg_set_cpus_cflags(uint32_t cflags_base) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + cpu->cflags_base = deposit32(cflags_base, CF_CLUSTER_SHIFT, 8, + cpu->cluster_index); + } +} + void tcg_cpus_destroy(CPUState *cpu) { cpu_thread_signal_destroyed(cpu); diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c index 0b0bfd35ab..ec46b88bfe 100644 --- a/accel/tcg/translate-all.c +++ b/accel/tcg/translate-all.c @@ -224,7 +224,6 @@ static void *l1_map[V_L1_MAX_SIZE]; TCGContext tcg_init_ctx; __thread TCGContext *tcg_ctx; TBContext tb_ctx; -bool parallel_cpus; static void page_table_config_init(void) { diff --git a/linux-user/main.c b/linux-user/main.c index 81f48ff54e..c37040ceec 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -205,6 +205,7 @@ CPUArchState *cpu_copy(CPUArchState *env) /* Reset non arch specific state */ cpu_reset(new_cpu); + new_cpu->cflags_base = cpu->cflags_base; memcpy(new_env, env, sizeof(CPUArchState)); /* Clone all break/watchpoints. diff --git a/linux-user/sh4/signal.c b/linux-user/sh4/signal.c index cc89a48ff8..deb569babe 100644 --- a/linux-user/sh4/signal.c +++ b/linux-user/sh4/signal.c @@ -83,7 +83,7 @@ static abi_ulong get_sigframe(struct target_sigaction *ka, } /* Notice when we're in the middle of a gUSA region and reset. - Note that this will only occur for !parallel_cpus, as we will + Note that this will only occur for !CF_PARALLEL, as we will translate such sequences differently in a parallel context. */ static void unwind_gusa(CPUSH4State *regs) { diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 389ec09764..83a6e51de3 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -6481,6 +6481,16 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp, /* Grab a mutex so that thread setup appears atomic. */ pthread_mutex_lock(&clone_lock); + /* + * If this is our first additional thread, we need to ensure we + * generate code for parallel execution and flush old translations. + * Do this now so that the copy gets CF_PARALLEL too. + */ + if (!(cpu->cflags_base & CF_PARALLEL)) { + cpu->cflags_base |= CF_PARALLEL; + tb_flush(cpu); + } + /* we create a new CPU instance. */ new_env = cpu_copy(env); /* Init regs that differ from the parent. */ @@ -6521,14 +6531,6 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp, sigprocmask(SIG_BLOCK, &sigmask, &info.sigmask); cpu->random_seed = qemu_guest_random_seed_thread_part1(); - /* If this is our first additional thread, we need to ensure we - * generate code for parallel execution and flush old translations. - */ - if (!parallel_cpus) { - parallel_cpus = true; - tb_flush(cpu); - } - ret = pthread_create(&info.thread, &attr, clone_func, &info); /* TODO: Free new CPU state if thread creation failed. */ -- 2.25.1
