From patchwork Thu Feb 1 08:33:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Pu Lehui X-Patchwork-Id: 13540797 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 62F1EC47DDB for ; Thu, 1 Feb 2024 08:33:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=TuVNsYgFJTcFbSmJZEuKuPqK7FjNGGkhZBzioMEwo34=; b=slwEl7VsBkCnGi 095l99MMN+3Ek0AmP0JC5GD0xJgbfLD3z1hOGOXUSLQw4OTIWz2RwoNtoWe5SIWb7yBvMkUp5zC64 yfkKrJ3NUaNI/B0EzxPg3bAa/wUzzSJBOD928LulLp5iZltAjdiQRRkH7au8Nc3+jYMTeBYrtF/S2 ud7vatgnQsTBSHXiebs+Ky2GJ+upzOY7kJRY75JKMwu0IRKoPZelKjZzfBay8BlCsajaSKn68lyIY BUQ5wkRtdEvB8S+n5l/WHGIjjUFpAJHCPrWiCIj+2rVtfFS+FE9mEqkMqIH3nJQgwhU4R36I/b+dx 8RQ5iIXc0J1vCPf+XpRQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVSVU-0000000759J-08f0; Thu, 01 Feb 2024 08:33:12 +0000 Received: from [45.249.212.51] (helo=dggsgout11.his.huawei.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVSVQ-00000007576-2tD0 for linux-riscv@lists.infradead.org; Thu, 01 Feb 2024 08:33:10 +0000 Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4TQXGZ0Qj0z4f3mHc for ; Thu, 1 Feb 2024 16:32:54 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 9458E1A0199 for ; Thu, 1 Feb 2024 16:33:00 +0800 (CST) Received: from ultra.huawei.com (unknown [10.90.53.71]) by APP4 (Coremail) with SMTP id gCh0CgA3PnA8V7tlRXylCg--.9426S3; Thu, 01 Feb 2024 16:33:00 +0800 (CST) From: Pu Lehui To: bpf@vger.kernel.org, linux-riscv@lists.infradead.org, netdev@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Palmer Dabbelt , Luke Nelson , Pu Lehui , Pu Lehui Subject: [PATCH bpf-next v3 1/4] riscv, bpf: Remove redundant ctx->offset initialization Date: Thu, 1 Feb 2024 08:33:48 +0000 Message-Id: <20240201083351.943121-2-pulehui@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240201083351.943121-1-pulehui@huaweicloud.com> References: <20240201083351.943121-1-pulehui@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgA3PnA8V7tlRXylCg--.9426S3 X-Coremail-Antispam: 1UD129KBjvdXoW7XFW8Jr15KF1fuF45XrW5KFg_yoW3tFX_C3 4xta4fXrWrJa1qkw1jvr1rXr1qyw1rtFyruF1fXry5C3Z0qw1vy3s7KrnrGry7urn8ZrW8 WFZ7JrW7Xw1YgjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbD8FF20E14v26rWj6s0DM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGwA2048vs2IY02 0Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xv wVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r106r15McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY04 v7MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_ Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x 0EwIxGrwCI42IY6xIIjxv20xvE14v26r1I6r4UMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWx JVW8Jr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUSYLPUUUUU = X-CM-SenderInfo: psxovxtxl6x35dzhxuhorxvhhfrp/ X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240201_003308_935949_18B15587 X-CRM114-Status: UNSURE ( 6.79 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Pu Lehui There is no gain in initializing ctx->offset and prev_insns, and ctx->offset is already zero-initialized. Let's remove this code. Signed-off-by: Pu Lehui Acked-by: Björn Töpel --- arch/riscv/net/bpf_jit_core.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c index 7b70ccb7fec3..b271240f48c9 100644 --- a/arch/riscv/net/bpf_jit_core.c +++ b/arch/riscv/net/bpf_jit_core.c @@ -91,11 +91,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) goto out_offset; } - for (i = 0; i < prog->len; i++) { - prev_ninsns += 32; - ctx->offset[i] = prev_ninsns; - } - for (i = 0; i < NR_JIT_ITERATIONS; i++) { pass++; ctx->ninsns = 0; From patchwork Thu Feb 1 08:33:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Pu Lehui X-Patchwork-Id: 13540796 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8DB05C47DDF for ; 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Thu, 01 Feb 2024 08:33:13 +0000 Received: from [45.249.212.51] (helo=dggsgout11.his.huawei.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVSVQ-0000000756i-2tT1 for linux-riscv@lists.infradead.org; Thu, 01 Feb 2024 08:33:11 +0000 Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4TQXGf0vRQz4f3k5r for ; Thu, 1 Feb 2024 16:32:58 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id B28AD1A0175 for ; Thu, 1 Feb 2024 16:33:00 +0800 (CST) Received: from ultra.huawei.com (unknown [10.90.53.71]) by APP4 (Coremail) with SMTP id gCh0CgA3PnA8V7tlRXylCg--.9426S4; Thu, 01 Feb 2024 16:33:00 +0800 (CST) From: Pu Lehui To: bpf@vger.kernel.org, linux-riscv@lists.infradead.org, netdev@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Palmer Dabbelt , Luke Nelson , Pu Lehui , Pu Lehui Subject: [PATCH bpf-next v3 2/4] riscv, bpf: Using kvcalloc to allocate cache buffer Date: Thu, 1 Feb 2024 08:33:49 +0000 Message-Id: <20240201083351.943121-3-pulehui@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240201083351.943121-1-pulehui@huaweicloud.com> References: <20240201083351.943121-1-pulehui@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgA3PnA8V7tlRXylCg--.9426S4 X-Coremail-Antispam: 1UD129KBjvJXoW7WFW3Cw13GrWfGw4Utr4fXwb_yoW8ZF15pF 4DGrnxA3yjvr1kXF1vqr4kXFy5J3Wqg3W7GFWUuFyfXF90qrWrXan5C34Y9rZ8CrWFkryS v3yY9rnxu34kXwUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPj14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jryl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUGVWUXwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8Jw CI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUFrcTDUUU U X-CM-SenderInfo: psxovxtxl6x35dzhxuhorxvhhfrp/ X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240201_003309_119116_723D56AB X-CRM114-Status: UNSURE ( 9.61 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Pu Lehui It is unnecessary to allocate continuous physical memory for cache buffer, and when ebpf program is too large, it may cause memory allocation failure. Signed-off-by: Pu Lehui Acked-by: Björn Töpel --- arch/riscv/net/bpf_jit_comp64.c | 4 ++-- arch/riscv/net/bpf_jit_core.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index fda6b4f6a4c1..74f995abf2c2 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -911,7 +911,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, } if (fmod_ret->nr_links) { - branches_off = kcalloc(fmod_ret->nr_links, sizeof(int), GFP_KERNEL); + branches_off = kvcalloc(fmod_ret->nr_links, sizeof(int), GFP_KERNEL); if (!branches_off) return -ENOMEM; @@ -1001,7 +1001,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, ret = ctx->ninsns; out: - kfree(branches_off); + kvfree(branches_off); return ret; } diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c index b271240f48c9..5ba68b1888ab 100644 --- a/arch/riscv/net/bpf_jit_core.c +++ b/arch/riscv/net/bpf_jit_core.c @@ -80,7 +80,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) } ctx->prog = prog; - ctx->offset = kcalloc(prog->len, sizeof(int), GFP_KERNEL); + ctx->offset = kvcalloc(prog->len, sizeof(int), GFP_KERNEL); if (!ctx->offset) { prog = orig_prog; goto out_offset; @@ -188,7 +188,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) ctx->offset[i] = ninsns_rvoff(ctx->offset[i]); bpf_prog_fill_jited_linfo(prog, ctx->offset); out_offset: - kfree(ctx->offset); + kvfree(ctx->offset); kfree(jit_data); prog->aux->jit_data = NULL; } From patchwork Thu Feb 1 08:33:50 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Pu Lehui X-Patchwork-Id: 13540798 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ED810C4828E for ; 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Thu, 01 Feb 2024 08:33:15 +0000 Received: from [45.249.212.56] (helo=dggsgout12.his.huawei.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVSVS-0000000756j-3X3S for linux-riscv@lists.infradead.org; Thu, 01 Feb 2024 08:33:12 +0000 Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4TQXGc4DBRz4f3l2m for ; Thu, 1 Feb 2024 16:32:56 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id C99391A0390 for ; Thu, 1 Feb 2024 16:33:00 +0800 (CST) Received: from ultra.huawei.com (unknown [10.90.53.71]) by APP4 (Coremail) with SMTP id gCh0CgA3PnA8V7tlRXylCg--.9426S5; Thu, 01 Feb 2024 16:33:00 +0800 (CST) From: Pu Lehui To: bpf@vger.kernel.org, linux-riscv@lists.infradead.org, netdev@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Palmer Dabbelt , Luke Nelson , Pu Lehui , Pu Lehui Subject: [PATCH bpf-next v3 3/4] riscv, bpf: Add RV_TAILCALL_OFFSET macro to format tailcall offset Date: Thu, 1 Feb 2024 08:33:50 +0000 Message-Id: <20240201083351.943121-4-pulehui@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240201083351.943121-1-pulehui@huaweicloud.com> References: <20240201083351.943121-1-pulehui@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgA3PnA8V7tlRXylCg--.9426S5 X-Coremail-Antispam: 1UD129KBjvJXoW7WrW5JFW5uFyxXrW8ArykGrg_yoW8AF1xpF 4UCwn3uF9Yqr18Cry7AF4DWa1YkFn0qF47GrW3CrW3G3ZF9rykG3WDK3yYvry5CFy8Jr18 Jryq9w1fC34kArJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPY14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JrWl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUGVWUXwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr 1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUCXdbU UUUU= X-CM-SenderInfo: psxovxtxl6x35dzhxuhorxvhhfrp/ X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240201_003311_264006_6BA6AE3B X-CRM114-Status: UNSURE ( 9.48 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Pu Lehui Add RV_TAILCALL_OFFSET macro to format tailcall offset, and correct the relevant comments. Signed-off-by: Pu Lehui Acked-by: Björn Töpel --- arch/riscv/net/bpf_jit_comp64.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index 74f995abf2c2..3516d425c5eb 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -13,7 +13,9 @@ #include #include "bpf_jit.h" -#define RV_FENTRY_NINSNS 2 +#define RV_FENTRY_NINSNS 2 +/* fentry and TCC init insns will be skipped on tailcall */ +#define RV_TAILCALL_OFFSET ((RV_FENTRY_NINSNS + 1) * 4) #define RV_REG_TCC RV_REG_A6 #define RV_REG_TCC_SAVED RV_REG_S6 /* Store A6 in S6 if program do calls */ @@ -260,8 +262,7 @@ static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx) if (!is_tail_call) emit_addiw(RV_REG_A0, RV_REG_A5, 0, ctx); emit_jalr(RV_REG_ZERO, is_tail_call ? RV_REG_T3 : RV_REG_RA, - is_tail_call ? (RV_FENTRY_NINSNS + 1) * 4 : 0, /* skip reserved nops and TCC init */ - ctx); + is_tail_call ? RV_TAILCALL_OFFSET : 0, ctx); } static void emit_bcc(u8 cond, u8 rd, u8 rs, int rvoff, @@ -382,7 +383,7 @@ static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx) off = ninsns_rvoff(tc_ninsn - (ctx->ninsns - start_insn)); emit_branch(BPF_JEQ, RV_REG_T2, RV_REG_ZERO, off, ctx); - /* goto *(prog->bpf_func + 4); */ + /* goto *(prog->bpf_func + RV_TAILCALL_OFFSET); */ off = offsetof(struct bpf_prog, bpf_func); if (is_12b_check(off, insn)) return -1; From patchwork Thu Feb 1 08:33:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pu Lehui X-Patchwork-Id: 13540799 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 09881C48286 for ; 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Thu, 01 Feb 2024 08:33:14 +0000 Received: from [45.249.212.51] (helo=dggsgout11.his.huawei.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVSVQ-0000000756k-2t8W for linux-riscv@lists.infradead.org; Thu, 01 Feb 2024 08:33:11 +0000 Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4TQXGf2GWqz4f3k6D for ; Thu, 1 Feb 2024 16:32:58 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id E04A41A0175 for ; Thu, 1 Feb 2024 16:33:00 +0800 (CST) Received: from ultra.huawei.com (unknown [10.90.53.71]) by APP4 (Coremail) with SMTP id gCh0CgA3PnA8V7tlRXylCg--.9426S6; Thu, 01 Feb 2024 16:33:00 +0800 (CST) From: Pu Lehui To: bpf@vger.kernel.org, linux-riscv@lists.infradead.org, netdev@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Palmer Dabbelt , Luke Nelson , Pu Lehui , Pu Lehui Subject: [PATCH bpf-next v3 4/4] riscv, bpf: Mixing bpf2bpf and tailcalls Date: Thu, 1 Feb 2024 08:33:51 +0000 Message-Id: <20240201083351.943121-5-pulehui@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240201083351.943121-1-pulehui@huaweicloud.com> References: <20240201083351.943121-1-pulehui@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgA3PnA8V7tlRXylCg--.9426S6 X-Coremail-Antispam: 1UD129KBjvJXoWxtF4DWr1kZFy8Zr4ruF15Jwb_yoWfCw1Upa 4kKw4fCFW0qa15JFZrGF1DXw1Sk3yvvF9Ikry3Kwsaya1qqrykG3WxKayYvFy5Cr95Zw1x Xr4Dt3ZIga17JrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPI14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUGVWUXwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVW8JVW5JwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr 0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUA rcfUUUUU= X-CM-SenderInfo: psxovxtxl6x35dzhxuhorxvhhfrp/ X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240201_003309_140347_7008C931 X-CRM114-Status: GOOD ( 20.93 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Pu Lehui In the current RV64 JIT, if we just don't initialize the TCC in subprog, the TCC can be propagated from the parent process to the subprocess, but the TCC of the parent process cannot be restored when the subprocess exits. Since the RV64 TCC is initialized before saving the callee saved registers into the stack, we cannot use the callee saved register to pass the TCC, otherwise the original value of the callee saved register will be destroyed. So we implemented mixing bpf2bpf and tailcalls similar to x86_64, i.e. using a non-callee saved register to transfer the TCC between functions, and saving that register to the stack to protect the TCC value. At the same time, we also consider the scenario of mixing trampoline. Tests test_bpf.ko and test_verifier have passed, as well as the relative testcases of test_progs*. Signed-off-by: Pu Lehui --- arch/riscv/net/bpf_jit.h | 1 + arch/riscv/net/bpf_jit_comp64.c | 88 +++++++++++++-------------------- 2 files changed, 36 insertions(+), 53 deletions(-) diff --git a/arch/riscv/net/bpf_jit.h b/arch/riscv/net/bpf_jit.h index 8b35f12a4452..d8be89dadf18 100644 --- a/arch/riscv/net/bpf_jit.h +++ b/arch/riscv/net/bpf_jit.h @@ -81,6 +81,7 @@ struct rv_jit_context { int nexentries; unsigned long flags; int stack_size; + int tcc_offset; }; /* Convert from ninsns to bytes. */ diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index 3516d425c5eb..25cd7808e262 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -13,13 +13,11 @@ #include #include "bpf_jit.h" +#define RV_REG_TCC RV_REG_A6 #define RV_FENTRY_NINSNS 2 /* fentry and TCC init insns will be skipped on tailcall */ #define RV_TAILCALL_OFFSET ((RV_FENTRY_NINSNS + 1) * 4) -#define RV_REG_TCC RV_REG_A6 -#define RV_REG_TCC_SAVED RV_REG_S6 /* Store A6 in S6 if program do calls */ - static const int regmap[] = { [BPF_REG_0] = RV_REG_A5, [BPF_REG_1] = RV_REG_A0, @@ -51,14 +49,12 @@ static const int pt_regmap[] = { }; enum { - RV_CTX_F_SEEN_TAIL_CALL = 0, RV_CTX_F_SEEN_CALL = RV_REG_RA, RV_CTX_F_SEEN_S1 = RV_REG_S1, RV_CTX_F_SEEN_S2 = RV_REG_S2, RV_CTX_F_SEEN_S3 = RV_REG_S3, RV_CTX_F_SEEN_S4 = RV_REG_S4, RV_CTX_F_SEEN_S5 = RV_REG_S5, - RV_CTX_F_SEEN_S6 = RV_REG_S6, }; static u8 bpf_to_rv_reg(int bpf_reg, struct rv_jit_context *ctx) @@ -71,7 +67,6 @@ static u8 bpf_to_rv_reg(int bpf_reg, struct rv_jit_context *ctx) case RV_CTX_F_SEEN_S3: case RV_CTX_F_SEEN_S4: case RV_CTX_F_SEEN_S5: - case RV_CTX_F_SEEN_S6: __set_bit(reg, &ctx->flags); } return reg; @@ -86,7 +81,6 @@ static bool seen_reg(int reg, struct rv_jit_context *ctx) case RV_CTX_F_SEEN_S3: case RV_CTX_F_SEEN_S4: case RV_CTX_F_SEEN_S5: - case RV_CTX_F_SEEN_S6: return test_bit(reg, &ctx->flags); } return false; @@ -102,32 +96,6 @@ static void mark_call(struct rv_jit_context *ctx) __set_bit(RV_CTX_F_SEEN_CALL, &ctx->flags); } -static bool seen_call(struct rv_jit_context *ctx) -{ - return test_bit(RV_CTX_F_SEEN_CALL, &ctx->flags); -} - -static void mark_tail_call(struct rv_jit_context *ctx) -{ - __set_bit(RV_CTX_F_SEEN_TAIL_CALL, &ctx->flags); -} - -static bool seen_tail_call(struct rv_jit_context *ctx) -{ - return test_bit(RV_CTX_F_SEEN_TAIL_CALL, &ctx->flags); -} - -static u8 rv_tail_call_reg(struct rv_jit_context *ctx) -{ - mark_tail_call(ctx); - - if (seen_call(ctx)) { - __set_bit(RV_CTX_F_SEEN_S6, &ctx->flags); - return RV_REG_S6; - } - return RV_REG_A6; -} - static bool is_32b_int(s64 val) { return -(1L << 31) <= val && val < (1L << 31); @@ -252,10 +220,6 @@ static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx) emit_ld(RV_REG_S5, store_offset, RV_REG_SP, ctx); store_offset -= 8; } - if (seen_reg(RV_REG_S6, ctx)) { - emit_ld(RV_REG_S6, store_offset, RV_REG_SP, ctx); - store_offset -= 8; - } emit_addi(RV_REG_SP, RV_REG_SP, stack_adjust, ctx); /* Set return value. */ @@ -343,7 +307,6 @@ static void emit_branch(u8 cond, u8 rd, u8 rs, int rvoff, static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx) { int tc_ninsn, off, start_insn = ctx->ninsns; - u8 tcc = rv_tail_call_reg(ctx); /* a0: &ctx * a1: &array @@ -366,9 +329,11 @@ static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx) /* if (--TCC < 0) * goto out; */ - emit_addi(RV_REG_TCC, tcc, -1, ctx); + emit_ld(RV_REG_TCC, ctx->tcc_offset, RV_REG_SP, ctx); + emit_addi(RV_REG_TCC, RV_REG_TCC, -1, ctx); off = ninsns_rvoff(tc_ninsn - (ctx->ninsns - start_insn)); emit_branch(BPF_JSLT, RV_REG_TCC, RV_REG_ZERO, off, ctx); + emit_sd(RV_REG_SP, ctx->tcc_offset, RV_REG_TCC, ctx); /* prog = array->ptrs[index]; * if (!prog) @@ -767,7 +732,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, int i, ret, offset; int *branches_off = NULL; int stack_size = 0, nregs = m->nr_args; - int retval_off, args_off, nregs_off, ip_off, run_ctx_off, sreg_off; + int retval_off, args_off, nregs_off, ip_off, run_ctx_off, sreg_off, tcc_off; struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY]; struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT]; struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN]; @@ -812,6 +777,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, * * FP - sreg_off [ callee saved reg ] * + * FP - tcc_off [ tail call count ] BPF_TRAMP_F_TAIL_CALL_CTX + * * [ pads ] pads for 16 bytes alignment */ @@ -853,6 +820,11 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, stack_size += 8; sreg_off = stack_size; + if (flags & BPF_TRAMP_F_TAIL_CALL_CTX) { + stack_size += 8; + tcc_off = stack_size; + } + stack_size = round_up(stack_size, 16); if (!is_struct_ops) { @@ -879,6 +851,10 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, emit_addi(RV_REG_FP, RV_REG_SP, stack_size, ctx); } + /* store tail call count */ + if (flags & BPF_TRAMP_F_TAIL_CALL_CTX) + emit_sd(RV_REG_FP, -tcc_off, RV_REG_TCC, ctx); + /* callee saved register S1 to pass start time */ emit_sd(RV_REG_FP, -sreg_off, RV_REG_S1, ctx); @@ -932,6 +908,9 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, if (flags & BPF_TRAMP_F_CALL_ORIG) { restore_args(nregs, args_off, ctx); + /* restore TCC to RV_REG_TCC before calling the original function */ + if (flags & BPF_TRAMP_F_TAIL_CALL_CTX) + emit_ld(RV_REG_TCC, -tcc_off, RV_REG_FP, ctx); ret = emit_call((const u64)orig_call, true, ctx); if (ret) goto out; @@ -963,6 +942,9 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, ret = emit_call((const u64)__bpf_tramp_exit, true, ctx); if (ret) goto out; + } else if (flags & BPF_TRAMP_F_TAIL_CALL_CTX) { + /* restore TCC to RV_REG_TCC before calling the original function */ + emit_ld(RV_REG_TCC, -tcc_off, RV_REG_FP, ctx); } if (flags & BPF_TRAMP_F_RESTORE_REGS) @@ -1455,6 +1437,9 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, if (ret < 0) return ret; + /* restore TCC from stack to RV_REG_TCC */ + emit_ld(RV_REG_TCC, ctx->tcc_offset, RV_REG_SP, ctx); + ret = emit_call(addr, fixed_addr, ctx); if (ret) return ret; @@ -1733,8 +1718,7 @@ void bpf_jit_build_prologue(struct rv_jit_context *ctx) stack_adjust += 8; if (seen_reg(RV_REG_S5, ctx)) stack_adjust += 8; - if (seen_reg(RV_REG_S6, ctx)) - stack_adjust += 8; + stack_adjust += 8; /* RV_REG_TCC */ stack_adjust = round_up(stack_adjust, 16); stack_adjust += bpf_stack_adjust; @@ -1749,7 +1733,8 @@ void bpf_jit_build_prologue(struct rv_jit_context *ctx) * (TCC) register. This instruction is skipped for tail calls. * Force using a 4-byte (non-compressed) instruction. */ - emit(rv_addi(RV_REG_TCC, RV_REG_ZERO, MAX_TAIL_CALL_CNT), ctx); + if (!bpf_is_subprog(ctx->prog)) + emit(rv_addi(RV_REG_TCC, RV_REG_ZERO, MAX_TAIL_CALL_CNT), ctx); emit_addi(RV_REG_SP, RV_REG_SP, -stack_adjust, ctx); @@ -1779,22 +1764,14 @@ void bpf_jit_build_prologue(struct rv_jit_context *ctx) emit_sd(RV_REG_SP, store_offset, RV_REG_S5, ctx); store_offset -= 8; } - if (seen_reg(RV_REG_S6, ctx)) { - emit_sd(RV_REG_SP, store_offset, RV_REG_S6, ctx); - store_offset -= 8; - } + emit_sd(RV_REG_SP, store_offset, RV_REG_TCC, ctx); + ctx->tcc_offset = store_offset; emit_addi(RV_REG_FP, RV_REG_SP, stack_adjust, ctx); if (bpf_stack_adjust) emit_addi(RV_REG_S5, RV_REG_SP, bpf_stack_adjust, ctx); - /* Program contains calls and tail calls, so RV_REG_TCC need - * to be saved across calls. - */ - if (seen_tail_call(ctx) && seen_call(ctx)) - emit_mv(RV_REG_TCC_SAVED, RV_REG_TCC, ctx); - ctx->stack_size = stack_adjust; } @@ -1807,3 +1784,8 @@ bool bpf_jit_supports_kfunc_call(void) { return true; } + +bool bpf_jit_supports_subprog_tailcalls(void) +{ + return true; +}