From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60235) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dY1qO-00016Y-AP for qemu-devel@nongnu.org; Wed, 19 Jul 2017 23:09:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dY1qJ-0005r4-Sx for qemu-devel@nongnu.org; Wed, 19 Jul 2017 23:09:40 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:33885) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dY1qJ-0005pk-Nv for qemu-devel@nongnu.org; Wed, 19 Jul 2017 23:09:35 -0400 From: "Emilio G. Cota" Date: Wed, 19 Jul 2017 23:09:07 -0400 Message-Id: <1500520169-23367-22-git-send-email-cota@braap.org> In-Reply-To: <1500520169-23367-1-git-send-email-cota@braap.org> References: <1500520169-23367-1-git-send-email-cota@braap.org> Subject: [Qemu-devel] [PATCH v3 21/43] cpu-exec: lookup/generate TB outside exclusive region during step_atomic List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Richard Henderson Now that all code generation has been converted to check CF_PARALLEL, we can generate !CF_PARALLEL code without having yet set !parallel_cpus -- and therefore without having to be in the exclusive region during cpu_exec_step_atomic. While at it, merge cpu_exec_step into cpu_exec_step_atomic. Reviewed-by: Richard Henderson Signed-off-by: Emilio G. Cota --- accel/tcg/cpu-exec.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index b71e015..526cab3 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -223,30 +223,40 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, } #endif -static void cpu_exec_step(CPUState *cpu) +void cpu_exec_step_atomic(CPUState *cpu) { CPUClass *cc = CPU_GET_CLASS(cpu); TranslationBlock *tb; target_ulong cs_base, pc; uint32_t flags; uint32_t cflags = 1 | CF_IGNORE_ICOUNT; + uint32_t cf_mask = cflags & CF_HASH_MASK; if (sigsetjmp(cpu->jmp_env, 0) == 0) { - tb = tb_lookup__cpu_state(cpu, &pc, &cs_base, &flags, - cflags & CF_HASH_MASK); + tb = tb_lookup__cpu_state(cpu, &pc, &cs_base, &flags, cf_mask); if (tb == NULL) { mmap_lock(); tb_lock(); - tb = tb_gen_code(cpu, pc, cs_base, flags, cflags); + tb = tb_htable_lookup(cpu, pc, cs_base, flags, cf_mask); + if (likely(tb == NULL)) { + tb = tb_gen_code(cpu, pc, cs_base, flags, cflags); + } tb_unlock(); mmap_unlock(); } + start_exclusive(); + + /* Since we got here, we know that parallel_cpus must be true. */ + parallel_cpus = false; cc->cpu_exec_enter(cpu); /* execute the generated code */ trace_exec_tb(tb, pc); cpu_tb_exec(cpu, tb); cc->cpu_exec_exit(cpu); + parallel_cpus = true; + + end_exclusive(); } else { /* We may have exited due to another problem here, so we need * to reset any tb_locks we may have taken but didn't release. @@ -260,18 +270,6 @@ static void cpu_exec_step(CPUState *cpu) } } -void cpu_exec_step_atomic(CPUState *cpu) -{ - start_exclusive(); - - /* Since we got here, we know that parallel_cpus must be true. */ - parallel_cpus = false; - cpu_exec_step(cpu); - parallel_cpus = true; - - end_exclusive(); -} - struct tb_desc { target_ulong pc; target_ulong cs_base; -- 2.7.4