From patchwork Sat Nov 9 00:41:55 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vadim Fedorenko X-Patchwork-Id: 13869118 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B1E798C07 for ; Sat, 9 Nov 2024 00:42:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=67.231.153.30 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731112959; cv=none; b=rM2aPM4uJpman0vuiWBU3OXavInPztciowj+43Nj57OTw72OfqfZXL7SWZponEGeCMnzFw9M9Dqxxb/chb8SIFBgVLBwt+TTxD/tPWRwbwnAdx+WBAV7sPNFRZMOnrM+G4YFo61H1jq9XTE4fVLLuEhZnJVxITLwz1Y9jBg5kpw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731112959; c=relaxed/simple; bh=lCA7kE8eJPbbby/OWYXwaSgudjElro42JjrwaPz8fko=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hpc7L5/Ef3Hr4o+pfuDM4ucWG9HwRZIWEHjRELfVFZGwqpgH/G0BHIVbcJi4xvCbqI33quelRzCYFmYdhmDAYFDqKfBEY56Nf4TWpKB5aMkF3KUtqyjVrOSUTvHyEmVFsh4/Vws6iZzRLOKLOS9KzxPPd57oesI1uAMa3qhAkEQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com; spf=pass smtp.mailfrom=meta.com; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b=QVgvVCTb; arc=none smtp.client-ip=67.231.153.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=meta.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b="QVgvVCTb" Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.18.1.2/8.18.1.2) with ESMTP id 4A905Rcd031770; Fri, 8 Nov 2024 16:42:12 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=s2048-2021-q4; bh=KSj1dXaY4HBmCHkzSYAKNoaKkZ7HsCKIEK6LG7RtK+U=; b=QVgvVCTb/QvV A7YVp5WJdWUj0SpTMdnZtp/NOAp7umAE8ekwQKVgnMADiZuXzleqTC6HQMIDF6i7 XXl3ewzVYCHdujNL+sx90TMjEywEiVBDFCl5SjWz5IaA4kbqxwqrrMPhax+zNPl0 hjhqtOA6QVQ2YQjOTDUtoMYYVgoTov3928wV8ATX1i4ypyFJq/S2qguUxUOeC2C2 RcsrR7a4Vsye1CIEEuNQemQVRNdrZQV9EnHmH1pCo2Tp+pzADcv5/PcEFJWRguae CA3SlvczStP9qXD9GcTTKA5p/M/rRSPu/lvyNsnslFH6H9hG5H4LNflZShi0CGrk 4dn9Mv/6ig== Received: from mail.thefacebook.com ([163.114.134.16]) by m0001303.ppops.net (PPS) with ESMTPS id 42svvsg65e-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Fri, 08 Nov 2024 16:42:12 -0800 (PST) Received: from devvm4158.cln0.facebook.com (2620:10d:c085:108::4) by mail.thefacebook.com (2620:10d:c08b:78::2ac9) with Microsoft SMTP Server id 15.2.1544.11; Sat, 9 Nov 2024 00:42:08 +0000 From: Vadim Fedorenko To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Thomas Gleixner , Vadim Fedorenko , Mykola Lysenko , Jakub Kicinski CC: , , Vadim Fedorenko , Martin KaFai Lau Subject: [PATCH bpf-next v5 2/4] bpf: add bpf_cpu_cycles_to_ns helper Date: Fri, 8 Nov 2024 16:41:55 -0800 Message-ID: <20241109004158.2259301-2-vadfed@meta.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20241109004158.2259301-1-vadfed@meta.com> References: <20241109004158.2259301-1-vadfed@meta.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-ORIG-GUID: X2YPAdLbcbBEVufkNP00XKR47RdL772g X-Proofpoint-GUID: X2YPAdLbcbBEVufkNP00XKR47RdL772g X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-05_03,2024-10-04_01,2024-09-30_01 X-Patchwork-Delegate: bpf@iogearbox.net The new helper should be used to convert cycles received by bpf_get_cpu_cycle() into nanoseconds. Signed-off-by: Vadim Fedorenko Reviewed-by: Eduard Zingerman --- v5: * no changes v4: * change helper name to bpf_cpu_cycles_to_ns. * hide it behind CONFIG_GENERIC_GETTIMEOFDAY to avoid exposing on unsupported architectures. --- arch/x86/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ arch/x86/net/bpf_jit_comp32.c | 19 +++++++++++++++++++ include/linux/bpf.h | 1 + kernel/bpf/helpers.c | 10 +++++++++- 4 files changed, 51 insertions(+), 1 deletion(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 4f78ed93ee7f..ddc73d9a90f4 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -2146,6 +2147,24 @@ st: if (is_imm8(insn->off)) break; } + if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL && + imm32 == BPF_CALL_IMM(bpf_cpu_cycles_to_ns) && + boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { + u32 mult, shift; + + clocks_calc_mult_shift(&mult, &shift, tsc_khz, USEC_PER_SEC, 0); + /* imul RAX, RDI, mult */ + maybe_emit_mod(&prog, BPF_REG_1, BPF_REG_0, true); + EMIT2_off32(0x69, add_2reg(0xC0, BPF_REG_1, BPF_REG_0), + mult); + + /* shr RAX, shift (which is less than 64) */ + maybe_emit_1mod(&prog, BPF_REG_0, true); + EMIT3(0xC1, add_1reg(0xE8, BPF_REG_0), shift); + + break; + } + func = (u8 *) __bpf_call_base + imm32; if (tail_call_reachable) { LOAD_TAIL_CALL_CNT_PTR(bpf_prog->aux->stack_depth); @@ -3678,5 +3697,8 @@ bool bpf_jit_inlines_kfunc_call(s32 imm) { if (imm == BPF_CALL_IMM(bpf_get_cpu_cycles)) return true; + if (imm == BPF_CALL_IMM(bpf_cpu_cycles_to_ns) && + boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) + return true; return false; } diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c index e6097a371b69..34f762f28c82 100644 --- a/arch/x86/net/bpf_jit_comp32.c +++ b/arch/x86/net/bpf_jit_comp32.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -2100,6 +2101,24 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, EMIT2(0x0F, 0x31); break; } + if (imm32 == BPF_CALL_IMM(bpf_cpu_cycles_to_ns) && + boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { + u32 mult, shift; + + clocks_calc_mult_shift(&mult, &shift, tsc_khz, + USEC_PER_SEC, 0); + + /* move parameter to BPF_REG_0 */ + emit_ia32_mov_r64(true, bpf2ia32[BPF_REG_0], + bpf2ia32[BPF_REG_1], true, true, + &prog, bpf_prog->aux); + /* multiply parameter by mut */ + emit_ia32_mul_i64(bpf2ia32[BPF_REG_0], + mult, true, &prog); + /* shift parameter by shift which is less than 64 */ + emit_ia32_rsh_i64(bpf2ia32[BPF_REG_0], + shift, true, &prog); + } err = emit_kfunc_call(bpf_prog, image + addrs[i], diff --git a/include/linux/bpf.h b/include/linux/bpf.h index fed5f36d387a..46fa662d95e4 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -3331,6 +3331,7 @@ u64 bpf_get_raw_cpu_id(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); /* Inlined kfuncs */ #if IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY) u64 bpf_get_cpu_cycles(void); +u64 bpf_cpu_cycles_to_ns(u64 cycles); #endif #if defined(CONFIG_NET) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 5c6c0383ebf4..72d5819e5df2 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -25,6 +25,7 @@ #include #if IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY) #include +#include #endif #include "../../lib/kstrtox.h" @@ -3031,8 +3032,14 @@ __bpf_kfunc u64 bpf_get_cpu_cycles(void) { return __arch_get_hw_counter(1, NULL); } -#endif +__bpf_kfunc u64 bpf_cpu_cycles_to_ns(u64 cycles) +{ + const struct vdso_data *vd = __arch_get_k_vdso_data(); + + return mul_u64_u32_shr(cycles, vd->mult, vd->shift); +} +#endif __bpf_kfunc_end_defs(); BTF_KFUNCS_START(generic_btf_ids) @@ -3127,6 +3134,7 @@ BTF_ID_FLAGS(func, bpf_iter_kmem_cache_next, KF_ITER_NEXT | KF_RET_NULL | KF_SLE BTF_ID_FLAGS(func, bpf_iter_kmem_cache_destroy, KF_ITER_DESTROY | KF_SLEEPABLE) #if IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY) BTF_ID_FLAGS(func, bpf_get_cpu_cycles, KF_FASTCALL) +BTF_ID_FLAGS(func, bpf_cpu_cycles_to_ns, KF_FASTCALL) #endif BTF_KFUNCS_END(common_btf_ids)