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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 4FBB1C43603 for ; Mon, 9 Dec 2019 17:32:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 29A24214AF for ; Mon, 9 Dec 2019 17:32:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="sRk23x/J" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726675AbfLIRcA (ORCPT ); Mon, 9 Dec 2019 12:32:00 -0500 Received: from mail-pf1-f194.google.com ([209.85.210.194]:41538 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726230AbfLIRb7 (ORCPT ); Mon, 9 Dec 2019 12:31:59 -0500 Received: by mail-pf1-f194.google.com with SMTP id s18so7574207pfd.8; Mon, 09 Dec 2019 09:31:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Q72cQM+3SI70k7ctcpb9LKDM8a7LAen8E8Vv2d4hTLo=; b=sRk23x/JpxVKbzZj54qVRUi2aIExQ0SRE7GqFLD/hMDxEVsFavaeMfS44RU6oiuXfb H0xi5LdEkduZ2iYCJYodCJF6Ing7Rv1IW8FMsyWVB2+sCdRzMHiUhKXmMg3xSMH6nHsX ayoDJZab2LVWXwXub2wg/AlQtXMlEvPjhk8JTyMAKviCRlRECgURo0yOcgepZ2IDOykr W3UsS2Gn8bgOe6SddLX7KSOBEYFK9IYdxMuaWv45tRXpfXQSmLLWywYTazar2mRObXn5 1loXAYvQ7kzXfJ7qWWqSuEMjX6mcN+A83MnD5l6sHk/M+WOUax9WPdqqaHvnilPlsfcj gSCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Q72cQM+3SI70k7ctcpb9LKDM8a7LAen8E8Vv2d4hTLo=; b=QDxy+jmJ1Xo2KJOwZlCPmcenyIMnwDJ7oKj0PIu0v+DggwbVzpjIi/iGCbQQ+zmvMC /Y+TSW3d0r+ouiawLGhwdyiLIr1gd38woL0iYQr1ucAPlPVUKzCuikyo5oL3KBqm9Ni0 03OPB30o4y1dgg0O2xiDVNOUGcFTB2H92MoWzVdXwAbBYNV7j4PUDghIJ32XUriV2n4w ACdRnIUMxpWf37coR3abv9VHmnzo6qSeecG7KN125ZTioogkXQsXefghKDMOH7aAVU8S 43lSL0ngXYb/ywZsK0C97c51dX/EWvx6YSeok7utBdqoODveXOYMlAUA/WaQG0qXJI7g CyYQ== X-Gm-Message-State: APjAAAWaH4T9+9bW3VPGIMFo2Hz1Enz04FWy5z01xRVffN8U+IpYnpuj rhDvAvR68VegfnvLEC7lBIY= X-Google-Smtp-Source: APXvYqxlMvkVuCdFoizkUk0kiP7e9NabguDeK3+5YeBoqX6bG5u2+aRmcgQwBwQtLnS2H8IY30slww== X-Received: by 2002:a63:d501:: with SMTP id c1mr19227970pgg.356.1575912719116; Mon, 09 Dec 2019 09:31:59 -0800 (PST) Received: from btopel-mobl.ger.intel.com ([192.55.55.41]) by smtp.gmail.com with ESMTPSA id d23sm54943pfo.176.2019.12.09.09.31.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Dec 2019 09:31:58 -0800 (PST) From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= To: daniel@iogearbox.net, ast@kernel.org, netdev@vger.kernel.org Cc: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , linux-riscv@lists.infradead.org, bpf@vger.kernel.org Subject: [PATCH bpf-next 4/8] riscv, bpf: optimize BPF tail calls Date: Mon, 9 Dec 2019 18:31:32 +0100 Message-Id: <20191209173136.29615-5-bjorn.topel@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191209173136.29615-1-bjorn.topel@gmail.com> References: <20191209173136.29615-1-bjorn.topel@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Remove one addi, and instead use the offset part of jalr. Signed-off-by: Björn Töpel --- arch/riscv/net/bpf_jit_comp.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/arch/riscv/net/bpf_jit_comp.c b/arch/riscv/net/bpf_jit_comp.c index e9cc9832ac2c..cbcb33613d1d 100644 --- a/arch/riscv/net/bpf_jit_comp.c +++ b/arch/riscv/net/bpf_jit_comp.c @@ -562,7 +562,7 @@ static int epilogue_offset(struct rv_jit_context *ctx) return (to - from) << 2; } -static void __build_epilogue(u8 reg, struct rv_jit_context *ctx) +static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx) { int stack_adjust = ctx->stack_size, store_offset = stack_adjust - 8; @@ -599,9 +599,11 @@ static void __build_epilogue(u8 reg, struct rv_jit_context *ctx) emit(rv_addi(RV_REG_SP, RV_REG_SP, stack_adjust), ctx); /* Set return value. */ - if (reg == RV_REG_RA) + if (!is_tail_call) emit(rv_addi(RV_REG_A0, RV_REG_A5, 0), ctx); - emit(rv_jalr(RV_REG_ZERO, reg, 0), ctx); + emit(rv_jalr(RV_REG_ZERO, is_tail_call ? RV_REG_T3 : RV_REG_RA, + is_tail_call ? 4 : 0), /* skip TCC init */ + ctx); } static void emit_zext_32(u8 reg, struct rv_jit_context *ctx) @@ -664,9 +666,8 @@ static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx) if (is_12b_check(off, insn)) return -1; emit(rv_ld(RV_REG_T3, off, RV_REG_T2), ctx); - emit(rv_addi(RV_REG_T3, RV_REG_T3, 4), ctx); emit(rv_addi(RV_REG_TCC, RV_REG_T1, 0), ctx); - __build_epilogue(RV_REG_T3, ctx); + __build_epilogue(true, ctx); return 0; } @@ -1520,7 +1521,7 @@ static void build_prologue(struct rv_jit_context *ctx) static void build_epilogue(struct rv_jit_context *ctx) { - __build_epilogue(RV_REG_RA, ctx); + __build_epilogue(false, ctx); } static int build_body(struct rv_jit_context *ctx, bool extra_pass) -- 2.20.1