diff options
| -rw-r--r-- | cpu-exec.c | 12 | ||||
| -rw-r--r-- | include/exec/tb-context.h | 2 | ||||
| -rw-r--r-- | include/qom/cpu.h | 2 | ||||
| -rw-r--r-- | translate-all.c | 38 |
4 files changed, 31 insertions, 23 deletions
diff --git a/cpu-exec.c b/cpu-exec.c index 9f4bd0b6dd..8823d23df7 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -204,20 +204,16 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, TranslationBlock *orig_tb, bool ignore_icount) { TranslationBlock *tb; - bool old_tb_flushed; /* Should never happen. We only end up here when an existing TB is too long. */ if (max_cycles > CF_COUNT_MASK) max_cycles = CF_COUNT_MASK; - old_tb_flushed = cpu->tb_flushed; - cpu->tb_flushed = false; tb = tb_gen_code(cpu, orig_tb->pc, orig_tb->cs_base, orig_tb->flags, max_cycles | CF_NOCACHE | (ignore_icount ? CF_IGNORE_ICOUNT : 0)); - tb->orig_tb = cpu->tb_flushed ? NULL : orig_tb; - cpu->tb_flushed |= old_tb_flushed; + tb->orig_tb = orig_tb; /* execute the generated code */ trace_exec_tb_nocache(tb, tb->pc); cpu_tb_exec(cpu, tb); @@ -338,10 +334,7 @@ static inline TranslationBlock *tb_find(CPUState *cpu, tb_lock(); have_tb_lock = true; } - /* Check if translation buffer has been flushed */ - if (cpu->tb_flushed) { - cpu->tb_flushed = false; - } else if (!tb->invalid) { + if (!tb->invalid) { tb_add_jump(last_tb, tb_exit, tb); } } @@ -606,7 +599,6 @@ int cpu_exec(CPUState *cpu) break; } - atomic_mb_set(&cpu->tb_flushed, false); /* reset before first TB lookup */ for(;;) { cpu_handle_interrupt(cpu, &last_tb); tb = tb_find(cpu, last_tb, tb_exit); diff --git a/include/exec/tb-context.h b/include/exec/tb-context.h index dce95d92d6..c7f17f26e0 100644 --- a/include/exec/tb-context.h +++ b/include/exec/tb-context.h @@ -38,7 +38,7 @@ struct TBContext { QemuMutex tb_lock; /* statistics */ - int tb_flush_count; + unsigned tb_flush_count; int tb_phys_invalidate_count; }; diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 4092dd919b..5dfe74a0e7 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -253,7 +253,6 @@ struct qemu_work_item; * @crash_occurred: Indicates the OS reported a crash (panic) for this CPU * @tcg_exit_req: Set to force TCG to stop executing linked TBs for this * CPU and return to its top level loop. - * @tb_flushed: Indicates the translation buffer has been flushed. * @singlestep_enabled: Flags for single-stepping. * @icount_extra: Instructions until next timer event. * @icount_decr: Number of cycles left, with interrupt flag in high bit. @@ -306,7 +305,6 @@ struct CPUState { bool unplug; bool crash_occurred; bool exit_request; - bool tb_flushed; uint32_t interrupt_request; int singlestep_enabled; int64_t icount_extra; diff --git a/translate-all.c b/translate-all.c index e9bc90c654..8ca393c9d0 100644 --- a/translate-all.c +++ b/translate-all.c @@ -834,12 +834,19 @@ static void page_flush_tb(void) } /* flush all the translation blocks */ -/* XXX: tb_flush is currently not thread safe */ -void tb_flush(CPUState *cpu) +static void do_tb_flush(CPUState *cpu, void *data) { - if (!tcg_enabled()) { - return; + unsigned tb_flush_req = (unsigned) (uintptr_t) data; + + tb_lock(); + + /* If it's already been done on request of another CPU, + * just retry. + */ + if (tcg_ctx.tb_ctx.tb_flush_count != tb_flush_req) { + goto done; } + #if defined(DEBUG_FLUSH) printf("qemu: flush code_size=%ld nb_tbs=%d avg_tb_size=%ld\n", (unsigned long)(tcg_ctx.code_gen_ptr - tcg_ctx.code_gen_buffer), @@ -858,7 +865,6 @@ void tb_flush(CPUState *cpu) for (i = 0; i < TB_JMP_CACHE_SIZE; ++i) { atomic_set(&cpu->tb_jmp_cache[i], NULL); } - atomic_mb_set(&cpu->tb_flushed, true); } tcg_ctx.tb_ctx.nb_tbs = 0; @@ -868,7 +874,19 @@ void tb_flush(CPUState *cpu) tcg_ctx.code_gen_ptr = tcg_ctx.code_gen_buffer; /* XXX: flush processor icache at this point if cache flush is expensive */ - tcg_ctx.tb_ctx.tb_flush_count++; + atomic_mb_set(&tcg_ctx.tb_ctx.tb_flush_count, + tcg_ctx.tb_ctx.tb_flush_count + 1); + +done: + tb_unlock(); +} + +void tb_flush(CPUState *cpu) +{ + if (tcg_enabled()) { + uintptr_t tb_flush_req = atomic_mb_read(&tcg_ctx.tb_ctx.tb_flush_count); + async_safe_run_on_cpu(cpu, do_tb_flush, (void *) tb_flush_req); + } } #ifdef DEBUG_TB_CHECK @@ -1175,9 +1193,8 @@ TranslationBlock *tb_gen_code(CPUState *cpu, buffer_overflow: /* flush must be done */ tb_flush(cpu); - /* cannot fail at this point */ - tb = tb_alloc(pc); - assert(tb != NULL); + mmap_unlock(); + cpu_loop_exit(cpu); } gen_code_buf = tcg_ctx.code_gen_ptr; @@ -1775,7 +1792,8 @@ void dump_exec_info(FILE *f, fprintf_function cpu_fprintf) qht_statistics_destroy(&hst); cpu_fprintf(f, "\nStatistics:\n"); - cpu_fprintf(f, "TB flush count %d\n", tcg_ctx.tb_ctx.tb_flush_count); + cpu_fprintf(f, "TB flush count %u\n", + atomic_read(&tcg_ctx.tb_ctx.tb_flush_count)); cpu_fprintf(f, "TB invalidate count %d\n", tcg_ctx.tb_ctx.tb_phys_invalidate_count); cpu_fprintf(f, "TLB flush count %d\n", tlb_flush_count); |