First this fixes the fact that statistics where only being updated if the build was built with DEBUG_TLB. Also it now counts the flush cases based on the degree of synchronisation required to run. This is a more useful discriminator for seeing what is slowing down the translation.
Signed-off-by: Alex Bennée <[email protected]> --- cputlb.c | 27 ++++++++++++++++++++++++--- include/exec/cputlb.h | 4 +++- translate-all.c | 4 +++- 3 files changed, 30 insertions(+), 5 deletions(-) diff --git a/cputlb.c b/cputlb.c index f5d056cc08..224863ed76 100644 --- a/cputlb.c +++ b/cputlb.c @@ -92,8 +92,13 @@ static void flush_all_helper(CPUState *src, run_on_cpu_func fn, } } -/* statistics */ -int tlb_flush_count; +/* Useful statistics - in rough order of expensiveness to the whole + * simulation. Synced flushes are the most expensive as all vCPUs need + * to be paused for the flush. + */ +int tlb_self_flush_count; /* from vCPU context */ +int tlb_async_flush_count; /* Deferred flush */ +int tlb_synced_flush_count; /* Synced flush, all vCPUs halted */ /* This is OK because CPU architectures generally permit an * implementation to drop entries from the TLB at any time, so @@ -112,7 +117,6 @@ static void tlb_flush_nocheck(CPUState *cpu) } assert_cpu_is_self(cpu); - tlb_debug("(count: %d)\n", tlb_flush_count++); tb_lock(); @@ -131,6 +135,7 @@ static void tlb_flush_nocheck(CPUState *cpu) static void tlb_flush_global_async_work(CPUState *cpu, run_on_cpu_data data) { + atomic_inc(&tlb_async_flush_count); tlb_flush_nocheck(cpu); } @@ -143,6 +148,7 @@ void tlb_flush(CPUState *cpu) RUN_ON_CPU_NULL); } } else { + atomic_inc(&tlb_self_flush_count); tlb_flush_nocheck(cpu); } } @@ -157,6 +163,7 @@ void tlb_flush_all_cpus(CPUState *src_cpu) void tlb_flush_all_cpus_synced(CPUState *src_cpu) { const run_on_cpu_func fn = tlb_flush_global_async_work; + atomic_inc(&tlb_synced_flush_count); flush_all_helper(src_cpu, fn, RUN_ON_CPU_NULL); async_safe_run_on_cpu(src_cpu, fn, RUN_ON_CPU_NULL); } @@ -168,6 +175,7 @@ static void tlb_flush_by_mmuidx_async_work(CPUState *cpu, run_on_cpu_data data) int mmu_idx; assert_cpu_is_self(cpu); + atomic_inc(&tlb_async_flush_count); tb_lock(); @@ -206,6 +214,7 @@ void tlb_flush_by_mmuidx(CPUState *cpu, uint16_t idxmap) RUN_ON_CPU_HOST_INT(pending_flushes)); } } else { + atomic_inc(&tlb_self_flush_count); tlb_flush_by_mmuidx_async_work(cpu, RUN_ON_CPU_HOST_INT(idxmap)); } @@ -219,6 +228,7 @@ void tlb_flush_by_mmuidx_all_cpus(CPUState *src_cpu, uint16_t idxmap) flush_all_helper(src_cpu, fn, RUN_ON_CPU_HOST_INT(idxmap)); fn(src_cpu, RUN_ON_CPU_HOST_INT(idxmap)); + atomic_inc(&tlb_self_flush_count); } void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *src_cpu, @@ -230,6 +240,7 @@ void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *src_cpu, flush_all_helper(src_cpu, fn, RUN_ON_CPU_HOST_INT(idxmap)); async_safe_run_on_cpu(src_cpu, fn, RUN_ON_CPU_HOST_INT(idxmap)); + atomic_inc(&tlb_synced_flush_count); } @@ -282,6 +293,8 @@ static void tlb_flush_page_async_work(CPUState *cpu, run_on_cpu_data data) } tb_flush_jmp_cache(cpu, addr); + + atomic_inc(&tlb_async_flush_count); } void tlb_flush_page(CPUState *cpu, target_ulong addr) @@ -293,6 +306,7 @@ void tlb_flush_page(CPUState *cpu, target_ulong addr) RUN_ON_CPU_TARGET_PTR(addr)); } else { tlb_flush_page_async_work(cpu, RUN_ON_CPU_TARGET_PTR(addr)); + atomic_inc(&tlb_self_flush_count); } } @@ -329,6 +343,7 @@ static void tlb_flush_page_by_mmuidx_async_work(CPUState *cpu, } tb_flush_jmp_cache(cpu, addr); + atomic_inc(&tlb_async_flush_count); } static void tlb_check_page_and_flush_by_mmuidx_async_work(CPUState *cpu, @@ -351,6 +366,7 @@ static void tlb_check_page_and_flush_by_mmuidx_async_work(CPUState *cpu, RUN_ON_CPU_HOST_INT(mmu_idx_bitmap)); } else { tlb_flush_page_by_mmuidx_async_work(cpu, data); + atomic_inc(&tlb_self_flush_count); } } @@ -370,6 +386,7 @@ void tlb_flush_page_by_mmuidx(CPUState *cpu, target_ulong addr, uint16_t idxmap) } else { tlb_check_page_and_flush_by_mmuidx_async_work( cpu, RUN_ON_CPU_TARGET_PTR(addr_and_mmu_idx)); + atomic_inc(&tlb_self_flush_count); } } @@ -387,6 +404,7 @@ void tlb_flush_page_by_mmuidx_all_cpus(CPUState *src_cpu, target_ulong addr, flush_all_helper(src_cpu, fn, RUN_ON_CPU_TARGET_PTR(addr_and_mmu_idx)); fn(src_cpu, RUN_ON_CPU_TARGET_PTR(addr_and_mmu_idx)); + atomic_inc(&tlb_self_flush_count); } void tlb_flush_page_by_mmuidx_all_cpus_synced(CPUState *src_cpu, @@ -404,6 +422,7 @@ void tlb_flush_page_by_mmuidx_all_cpus_synced(CPUState *src_cpu, flush_all_helper(src_cpu, fn, RUN_ON_CPU_TARGET_PTR(addr_and_mmu_idx)); async_safe_run_on_cpu(src_cpu, fn, RUN_ON_CPU_TARGET_PTR(addr_and_mmu_idx)); + atomic_inc(&tlb_synced_flush_count); } void tlb_flush_page_all_cpus(CPUState *src, target_ulong addr) @@ -412,6 +431,7 @@ void tlb_flush_page_all_cpus(CPUState *src, target_ulong addr) flush_all_helper(src, fn, RUN_ON_CPU_TARGET_PTR(addr)); fn(src, RUN_ON_CPU_TARGET_PTR(addr)); + atomic_inc(&tlb_self_flush_count); } void tlb_flush_page_all_cpus_synced(CPUState *src, @@ -421,6 +441,7 @@ void tlb_flush_page_all_cpus_synced(CPUState *src, flush_all_helper(src, fn, RUN_ON_CPU_TARGET_PTR(addr)); async_safe_run_on_cpu(src, fn, RUN_ON_CPU_TARGET_PTR(addr)); + atomic_inc(&tlb_synced_flush_count); } /* update the TLBs so that writes to code in the virtual page 'addr' diff --git a/include/exec/cputlb.h b/include/exec/cputlb.h index 3f941783c5..5085384014 100644 --- a/include/exec/cputlb.h +++ b/include/exec/cputlb.h @@ -23,7 +23,9 @@ /* cputlb.c */ void tlb_protect_code(ram_addr_t ram_addr); void tlb_unprotect_code(ram_addr_t ram_addr); -extern int tlb_flush_count; +extern int tlb_self_flush_count; +extern int tlb_async_flush_count; +extern int tlb_synced_flush_count; #endif #endif diff --git a/translate-all.c b/translate-all.c index b3ee876526..0578ae6123 100644 --- a/translate-all.c +++ b/translate-all.c @@ -1927,7 +1927,9 @@ void dump_exec_info(FILE *f, fprintf_function cpu_fprintf) 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); + cpu_fprintf(f, "TLB flush counts self:%d async:%d synced:%d\n", + tlb_self_flush_count, tlb_async_flush_count, + tlb_synced_flush_count); tcg_dump_info(f, cpu_fprintf); tb_unlock(); -- 2.11.0
