From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E021C4361B for ; Mon, 14 Dec 2020 14:21:42 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D7DA922B47 for ; Mon, 14 Dec 2020 14:21:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D7DA922B47 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:39442 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1koojM-00077h-Nb for qemu-devel@archiver.kernel.org; Mon, 14 Dec 2020 09:21:40 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:36406) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kooSB-0001rz-DU for qemu-devel@nongnu.org; Mon, 14 Dec 2020 09:03:55 -0500 Received: from mail-ot1-x32b.google.com ([2607:f8b0:4864:20::32b]:37238) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kooS8-0003xm-KX for qemu-devel@nongnu.org; Mon, 14 Dec 2020 09:03:55 -0500 Received: by mail-ot1-x32b.google.com with SMTP id o11so15760047ote.4 for ; Mon, 14 Dec 2020 06:03:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=PE5zDJYupwBF6LFLJEA3Vgnp30HPDgVW1boJkF7byFo=; b=Wa68fek1X12CUOK+gMbuQ/TFhZrtUUcTu8d13SdLArDPFpOF1WN/DYYHl5gh7GnM+3 Ju03VB+HMsG3HFp4ewb2i3EghKpKBc38fIMRlmAXROHvCLjREmErTKNZsFLhWEtG9Yxd 38+N1chOFLuQrmwnDdnfUzvY36+tzY+4NcXUpJf1fbRpcOq6VdY6J3tPOjU4wN6w301Y caLyzOm58Yz+J2SZbJCy4kmnoKOwllel0uhrutrT9k36Brmd4R9uxk8KZ8ym82POd7vW liySuTRPLhKyzNXlC3yavgAsfFNdDhG/NX2t/I4pT/zzaiJ197lmWDOBFxtaLBQNGwDz kNKg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=PE5zDJYupwBF6LFLJEA3Vgnp30HPDgVW1boJkF7byFo=; b=gXjJsiHKOuLx/MzegPxFlw8ESvsT+02WDV9sH7ZF25NSOk3m76b/lafCd123wLUPM9 ahgjVvH2jGLjIDQdvJD3FTQSMUf9aFy4BQB58I6Ni64bGLAn4RfRjGTfsWAaVFwC64F+ coH5ZoR8E8XhZCoguctQCYIRw2YrO9viW4Z7Vkm8n6Lq0LNvXBt4aBWLrRmyokhAyaSI GYClnBt8Zm893wWMgi8HhBGVXS0uPb9f5gYRqRI6g2sZyIbQJBv0BbbUP96GOuX78zPm bGkCtcppHcip7+tciFI1Tm06YmxarDCdqh6CrOSKHsoOjUhX+3HNrHDPQrPrIcXZbDEC CPhQ== X-Gm-Message-State: AOAM5317K02LMsTtiobDijD3zWmUX5VH7Zmei787Co5lZtCnceIOo6w8 Voe3E27G2evjfrI1Kia5rRB16K8bAT4captk X-Google-Smtp-Source: ABdhPJzDyfJTTk46nOXZllp+EIetReafEfZXcot+0UQP9yaB71ffODP7o4Yaj/M8p1f1i06SVNci4w== X-Received: by 2002:a05:6830:114e:: with SMTP id x14mr19411679otq.253.1607954630753; Mon, 14 Dec 2020 06:03:50 -0800 (PST) Received: from localhost.localdomain (fixed-187-189-51-144.totalplay.net. [187.189.51.144]) by smtp.gmail.com with ESMTPSA id t24sm3940146oou.4.2020.12.14.06.03.49 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Dec 2020 06:03:50 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Subject: [PATCH v4 20/43] tcg: Return the TB pointer from the rx region from exit_tb Date: Mon, 14 Dec 2020 08:02:51 -0600 Message-Id: <20201214140314.18544-21-richard.henderson@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201214140314.18544-1-richard.henderson@linaro.org> References: <20201214140314.18544-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::32b; envelope-from=richard.henderson@linaro.org; helo=mail-ot1-x32b.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This produces a small pc-relative displacement within the generated code to the TB structure that preceeds it. Signed-off-by: Richard Henderson --- accel/tcg/cpu-exec.c | 35 ++++++++++++++++++++++------------- tcg/tcg-op.c | 13 ++++++++++++- 2 files changed, 34 insertions(+), 14 deletions(-) diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index 272d596e0c..8df0a1782e 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -144,12 +144,13 @@ static void init_delay_params(SyncClocks *sc, const CPUState *cpu) #endif /* CONFIG USER ONLY */ /* Execute a TB, and fix up the CPU state afterwards if necessary */ -static inline tcg_target_ulong cpu_tb_exec(CPUState *cpu, TranslationBlock *itb) +static inline TranslationBlock *cpu_tb_exec(CPUState *cpu, + TranslationBlock *itb, + int *tb_exit) { CPUArchState *env = cpu->env_ptr; uintptr_t ret; TranslationBlock *last_tb; - int tb_exit; const void *tb_ptr = itb->tc.ptr; qemu_log_mask_and_addr(CPU_LOG_EXEC, itb->pc, @@ -177,11 +178,20 @@ static inline tcg_target_ulong cpu_tb_exec(CPUState *cpu, TranslationBlock *itb) ret = tcg_qemu_tb_exec(env, tb_ptr); cpu->can_do_io = 1; - last_tb = (TranslationBlock *)(ret & ~TB_EXIT_MASK); - tb_exit = ret & TB_EXIT_MASK; - trace_exec_tb_exit(last_tb, tb_exit); + /* + * TODO: Delay swapping back to the read-write region of the TB + * until we actually need to modify the TB. The read-only copy, + * coming from the rx region, shares the same host TLB entry as + * the code that executed the exit_tb opcode that arrived here. + * If we insist on touching both the RX and the RW pages, we + * double the host TLB pressure. + */ + last_tb = tcg_splitwx_to_rw((void *)(ret & ~TB_EXIT_MASK)); + *tb_exit = ret & TB_EXIT_MASK; - if (tb_exit > TB_EXIT_IDX1) { + trace_exec_tb_exit(last_tb, *tb_exit); + + if (*tb_exit > TB_EXIT_IDX1) { /* We didn't start executing this TB (eg because the instruction * counter hit zero); we must restore the guest PC to the address * of the start of the TB. @@ -199,7 +209,7 @@ static inline tcg_target_ulong cpu_tb_exec(CPUState *cpu, TranslationBlock *itb) cc->set_pc(cpu, last_tb->pc); } } - return ret; + return last_tb; } #ifndef CONFIG_USER_ONLY @@ -210,6 +220,7 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, { TranslationBlock *tb; uint32_t cflags = curr_cflags() | CF_NOCACHE; + int tb_exit; if (ignore_icount) { cflags &= ~CF_USE_ICOUNT; @@ -227,7 +238,7 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, /* execute the generated code */ trace_exec_tb_nocache(tb, tb->pc); - cpu_tb_exec(cpu, tb); + cpu_tb_exec(cpu, tb, &tb_exit); mmap_lock(); tb_phys_invalidate(tb, -1); @@ -244,6 +255,7 @@ void cpu_exec_step_atomic(CPUState *cpu) uint32_t flags; uint32_t cflags = 1; uint32_t cf_mask = cflags & CF_HASH_MASK; + int tb_exit; if (sigsetjmp(cpu->jmp_env, 0) == 0) { start_exclusive(); @@ -260,7 +272,7 @@ void cpu_exec_step_atomic(CPUState *cpu) cc->cpu_exec_enter(cpu); /* execute the generated code */ trace_exec_tb(tb, pc); - cpu_tb_exec(cpu, tb); + cpu_tb_exec(cpu, tb, &tb_exit); cc->cpu_exec_exit(cpu); } else { /* @@ -653,13 +665,10 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb, TranslationBlock **last_tb, int *tb_exit) { - uintptr_t ret; int32_t insns_left; trace_exec_tb(tb, tb->pc); - ret = cpu_tb_exec(cpu, tb); - tb = (TranslationBlock *)(ret & ~TB_EXIT_MASK); - *tb_exit = ret & TB_EXIT_MASK; + tb = cpu_tb_exec(cpu, tb, tb_exit); if (*tb_exit != TB_EXIT_REQUESTED) { *last_tb = tb; return; diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c index e3dc0cb4cb..56bb8db040 100644 --- a/tcg/tcg-op.c +++ b/tcg/tcg-op.c @@ -2666,7 +2666,18 @@ void tcg_gen_extr32_i64(TCGv_i64 lo, TCGv_i64 hi, TCGv_i64 arg) void tcg_gen_exit_tb(const TranslationBlock *tb, unsigned idx) { - uintptr_t val = (uintptr_t)tb + idx; + /* + * Let the jit code return the read-only version of the + * TranslationBlock, so that we minimize the pc-relative + * distance of the address of the exit_tb code to TB. + * This will improve utilization of pc-relative address loads. + * + * TODO: Move this to translator_loop, so that all const + * TranslationBlock pointers refer to read-only memory. + * This requires coordination with targets that do not use + * the translator_loop. + */ + uintptr_t val = (uintptr_t)tcg_splitwx_to_rx((void *)tb) + idx; if (tb == NULL) { tcg_debug_assert(idx == 0); -- 2.25.1