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 C811FC43603 for ; Mon, 9 Dec 2019 17:32:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 981D320836 for ; Mon, 9 Dec 2019 17:32:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dHqonQVZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726816AbfLIRcG (ORCPT ); Mon, 9 Dec 2019 12:32:06 -0500 Received: from mail-pf1-f194.google.com ([209.85.210.194]:38998 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726230AbfLIRcG (ORCPT ); Mon, 9 Dec 2019 12:32:06 -0500 Received: by mail-pf1-f194.google.com with SMTP id 2so7576683pfx.6; Mon, 09 Dec 2019 09:32:05 -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=+poYiv+8PtDbY0kklYLAZ46MuOoXr5bUTyoS0TPIaGc=; b=dHqonQVZ3ujeSFRJMFtSGpE2eEwMEk45rbKxlpuuJmALXtzb+jILOwh6xuPC+D5KyN NZzpDTQIapqhXwCycBNG1+J5rVbbXoKHAdduigDRySfVkNxyFuVqN1xb7TIc2AzOrdKl aiorNkA4ycTHePbaALmZ+GE6KiAQHoTwCgB2KE+BFWdAXn3BtFQJkRqzkVo/NoBFIO8S 2FOnSdPLojp1MIarTbxJInL5vb3w/JWZIiBL9xmHuXjGACR1qRmK6oaSDPH2jnWns4XQ 36h5HQ0H/5wL3qwfjyOgJvAMoswfbDmWAUTueNFLXcQ37OkygjwjgVIN13djZeKbo8r9 chXw== 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=+poYiv+8PtDbY0kklYLAZ46MuOoXr5bUTyoS0TPIaGc=; b=jOlYIWrXJ1lcYb/h80mfuj8yY8x0s+/DJDxMs55baEo+ZvvDzTD5FWEg8OBrz5dGi5 f4tcwPmhai0k0HR9zTo6lybv1+3m4q01QYFl3uI5GJbLs9UfaGSIi87Dxx09nYqP2qBZ 7VjUaYUG+VPs4w4fBa9yLvbWjyO4G29ikgC9txnwqe1Yl4Dy7/ylDp1vW20shzRzm4NP IC2FWD4J5YLoukbQzMufXshRJujOU1crWYtFRWiIScxNi1UV6v3n7Svj6fJVvazvgmyz TLR15NYKhkcJJYRMNuc/LfdHEBBtda57rNIX6fMyn2eJgC2HY871pDk4RP+tpR2dMbul teUw== X-Gm-Message-State: APjAAAVlyl0wsG4d21Z5ylzzmptKBa1DX4Eoo4+lRKNMJubJPXDrJSpA U1bk3YWSaOQdxUsqbgg/lctoKBGJQfc= X-Google-Smtp-Source: APXvYqyGewL1ziYSiaxyGVrbvZGP4Pfkl6VVi14TKt9OHRmgsGBv1ENpkokaLMh/72xQ5D162f9Gqw== X-Received: by 2002:aa7:9af1:: with SMTP id y17mr30579052pfp.21.1575912724538; Mon, 09 Dec 2019 09:32:04 -0800 (PST) Received: from btopel-mobl.ger.intel.com ([192.55.55.41]) by smtp.gmail.com with ESMTPSA id d23sm54943pfo.176.2019.12.09.09.32.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Dec 2019 09:32:04 -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 6/8] riscv, bpf: optimize calls Date: Mon, 9 Dec 2019 18:31:34 +0100 Message-Id: <20191209173136.29615-7-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 Instead of using emit_imm() and emit_jalr() which can expand to six instructions, start using jal or auipc+jalr. Signed-off-by: Björn Töpel --- arch/riscv/net/bpf_jit_comp.c | 101 +++++++++++++++++++++------------- 1 file changed, 64 insertions(+), 37 deletions(-) diff --git a/arch/riscv/net/bpf_jit_comp.c b/arch/riscv/net/bpf_jit_comp.c index f7b1ae3a968f..260df0a87fd3 100644 --- a/arch/riscv/net/bpf_jit_comp.c +++ b/arch/riscv/net/bpf_jit_comp.c @@ -724,11 +724,12 @@ static void emit_sext_32_rd(u8 *rd, struct rv_jit_context *ctx) *rd = RV_REG_T2; } -static void emit_jump_and_link(u8 rd, int rvoff, struct rv_jit_context *ctx) +static void emit_jump_and_link(u8 rd, s64 rvoff, bool force_jalr, + struct rv_jit_context *ctx) { s64 upper, lower; - if (is_21b_int(rvoff)) { + if (rvoff && is_21b_int(rvoff) && !force_jalr) { emit(rv_jal(rd, rvoff >> 1), ctx); return; } @@ -848,6 +849,28 @@ static bool is_signed_bpf_cond(u8 cond) cond == BPF_JSGE || cond == BPF_JSLE; } +static int emit_call(bool fixed, u64 addr, struct rv_jit_context *ctx) +{ + s64 off = 0; + u64 ip; + u8 rd; + + if (addr && ctx->insns) { + ip = (u64)(long)(ctx->insns + ctx->ninsns); + off = addr - ip; + if (!is_32b_int(off)) { + pr_err("bpf-jit: target call addr %pK is out of range\n", + (void *)addr); + return -ERANGE; + } + } + + emit_jump_and_link(RV_REG_RA, off, !fixed, ctx); + rd = bpf_to_rv_reg(BPF_REG_0, ctx); + emit(rv_addi(rd, RV_REG_A0, 0), ctx); + return 0; +} + static int emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, bool extra_pass) { @@ -1123,7 +1146,7 @@ static int emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, /* JUMP off */ case BPF_JMP | BPF_JA: rvoff = rv_offset(i, off, ctx); - emit_jump_and_link(RV_REG_ZERO, rvoff, ctx); + emit_jump_and_link(RV_REG_ZERO, rvoff, false, ctx); break; /* IF (dst COND src) JUMP off */ @@ -1225,7 +1248,7 @@ static int emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, case BPF_JMP | BPF_CALL: { bool fixed; - int i, ret; + int ret; u64 addr; mark_call(ctx); @@ -1233,20 +1256,9 @@ static int emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, &fixed); if (ret < 0) return ret; - if (fixed) { - emit_imm(RV_REG_T1, addr, ctx); - } else { - i = ctx->ninsns; - emit_imm(RV_REG_T1, addr, ctx); - for (i = ctx->ninsns - i; i < 8; i++) { - /* nop */ - emit(rv_addi(RV_REG_ZERO, RV_REG_ZERO, 0), - ctx); - } - } - emit(rv_jalr(RV_REG_RA, RV_REG_T1, 0), ctx); - rd = bpf_to_rv_reg(BPF_REG_0, ctx); - emit(rv_addi(rd, RV_REG_A0, 0), ctx); + ret = emit_call(fixed, addr, ctx); + if (ret) + return ret; break; } /* tail call */ @@ -1261,7 +1273,7 @@ static int emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, break; rvoff = epilogue_offset(ctx); - emit_jump_and_link(RV_REG_ZERO, rvoff, ctx); + emit_jump_and_link(RV_REG_ZERO, rvoff, false, ctx); break; /* dst = imm64 */ @@ -1524,7 +1536,7 @@ static void build_epilogue(struct rv_jit_context *ctx) __build_epilogue(false, ctx); } -static int build_body(struct rv_jit_context *ctx, bool extra_pass) +static int build_body(struct rv_jit_context *ctx, bool extra_pass, int *offset) { const struct bpf_prog *prog = ctx->prog; int i; @@ -1536,12 +1548,12 @@ static int build_body(struct rv_jit_context *ctx, bool extra_pass) ret = emit_insn(insn, ctx, extra_pass); if (ret > 0) { i++; - if (ctx->insns == NULL) - ctx->offset[i] = ctx->ninsns; + if (offset) + offset[i] = ctx->ninsns; continue; } - if (ctx->insns == NULL) - ctx->offset[i] = ctx->ninsns; + if (offset) + offset[i] = ctx->ninsns; if (ret) return ret; } @@ -1569,8 +1581,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) struct bpf_prog *tmp, *orig_prog = prog; int pass = 0, prev_ninsns = 0, i; struct rv_jit_data *jit_data; + unsigned int image_size = 0; struct rv_jit_context *ctx; - unsigned int image_size; if (!prog->jit_requested) return orig_prog; @@ -1615,36 +1627,51 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) for (i = 0; i < 16; i++) { pass++; ctx->ninsns = 0; - if (build_body(ctx, extra_pass)) { + if (build_body(ctx, extra_pass, ctx->offset)) { prog = orig_prog; goto out_offset; } build_prologue(ctx); ctx->epilogue_offset = ctx->ninsns; build_epilogue(ctx); - if (ctx->ninsns == prev_ninsns) - break; + + if (ctx->ninsns == prev_ninsns) { + if (jit_data->header) + break; + + image_size = sizeof(u32) * ctx->ninsns; + jit_data->header = + bpf_jit_binary_alloc(image_size, + &jit_data->image, + sizeof(u32), + bpf_fill_ill_insns); + if (!jit_data->header) { + prog = orig_prog; + goto out_offset; + } + + ctx->insns = (u32 *)jit_data->image; + /* Now, when the image is allocated, the image + * can potentially shrink more (auipc/jalr -> + * jal). + */ + } prev_ninsns = ctx->ninsns; } - /* Allocate image, now that we know the size. */ - image_size = sizeof(u32) * ctx->ninsns; - jit_data->header = bpf_jit_binary_alloc(image_size, &jit_data->image, - sizeof(u32), - bpf_fill_ill_insns); - if (!jit_data->header) { + if (i == 16) { + pr_err("bpf-jit: image did not converge in <%d passes!\n", i); + bpf_jit_binary_free(jit_data->header); prog = orig_prog; goto out_offset; } - /* Second, real pass, that acutally emits the image. */ - ctx->insns = (u32 *)jit_data->image; skip_init_ctx: pass++; ctx->ninsns = 0; build_prologue(ctx); - if (build_body(ctx, extra_pass)) { + if (build_body(ctx, extra_pass, NULL)) { bpf_jit_binary_free(jit_data->header); prog = orig_prog; goto out_offset; -- 2.20.1