Received: by 2002:ab2:1347:0:b0:1f4:ac9d:b246 with SMTP id g7csp97082lqg; Wed, 10 Apr 2024 17:15:58 -0700 (PDT) X-Forwarded-Encrypted: i=3; AJvYcCXjasMOaBonWuhrxiU+t6ddKrKqmsUCbKKZ7Z80SghaSVsRDnRHgQF4iOqZ8P1N/oAZykoxji0R5YSjSTPkeLNtxJy4yu8f6cfr/abrSw== X-Google-Smtp-Source: AGHT+IFwvs1gge/b6/5iXPye5VBhXoKwsJ/dgNreZppyStsNJojTJI0qNHPZxOsnxWlMK3Xq+zoG X-Received: by 2002:a17:906:2499:b0:a51:85d8:5892 with SMTP id e25-20020a170906249900b00a5185d85892mr646924ejb.36.1712794558118; Wed, 10 Apr 2024 17:15:58 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1712794558; cv=pass; d=google.com; s=arc-20160816; b=PG/m2AoOfQKqqPGvvCQg0VoqwsUHobDZRVbMvMiy/x1V/Qz+vQyOAWiS9AbWE0jm4i QYAQ1frSMqFq6RbuF9zFfBGpRSpAB+7Tk+QFk4MVbL2WYch8szmIFoJvRTYj5LQFP8rr 6lbnEncim7Fw1ar44tE3O0d22gSHdCjCHKDfOLp6PW13ZQcyfLZgYJWRFDVvpDJuRjPh NkXX7hZcOav5Ac/7jfRRrkAm+LaLOxElfBoC6Fc0e+RqknoI8w35gbyu+Y2rDCVDjgyZ /Cy9YDYNmrCezAtDkhZGnPhZNrfy+OBKCzm+9+JpIhI3aOZ3WiFsOnN05zcyR5ZVbEad BtJQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:list-unsubscribe :list-subscribe:list-id:precedence:references:in-reply-to:message-id :date:subject:cc:to:from:dkim-signature; bh=CMnuEfMmhTbxsHuHfbuFwM+0a2BQQDxSVtnwpOahwcE=; fh=MkZxQ8wToPY4nGax2MWhoW2aeRGSsPNQv6VhgppkNH8=; b=1Fgt/i2gXFUH0HsTTWoAIV2enmjFP4iZxDkmqX8Yuf20dcdkYQG8f3x7QvdIkK3w1y V3i2N/exn+32iNMcz2M5Smjaf7PwNIPpPUNXJ/uJRqC47CBrE7M6WRqWlpUmAoRac/ZF rIoxUN8Pnj6lLQ+LXUXzSzC8WktsygtOxcVc6/jlBx3qewPt0YQftJHN3ubL7HnyTD2d lHzYvzvUQjeCssCd8dlCa1QasCNuBd6MbyhK4mI4gBhNusA8B6vFdpw5kUDa5Jb7RjVS sTJFBB/37ZPThUrVTr0ISEN40sKy3wJLfVEkb7qACm+V9KaxUSbufNRjmdB91aXYecab Crhw==; dara=google.com ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@rivosinc-com.20230601.gappssmtp.com header.s=20230601 header.b=diTtMBnK; arc=pass (i=1 spf=pass spfdomain=rivosinc.com dkim=pass dkdomain=rivosinc-com.20230601.gappssmtp.com); spf=pass (google.com: domain of linux-kernel+bounces-139577-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) smtp.mailfrom="linux-kernel+bounces-139577-linux.lists.archive=gmail.com@vger.kernel.org" Return-Path: Received: from am.mirrors.kernel.org (am.mirrors.kernel.org. [2604:1380:4601:e00::3]) by mx.google.com with ESMTPS id a12-20020a1709062b0c00b00a51d844d82bsi156462ejg.377.2024.04.10.17.15.58 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Apr 2024 17:15:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-139577-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3; Authentication-Results: mx.google.com; dkim=pass header.i=@rivosinc-com.20230601.gappssmtp.com header.s=20230601 header.b=diTtMBnK; arc=pass (i=1 spf=pass spfdomain=rivosinc.com dkim=pass dkdomain=rivosinc-com.20230601.gappssmtp.com); spf=pass (google.com: domain of linux-kernel+bounces-139577-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) smtp.mailfrom="linux-kernel+bounces-139577-linux.lists.archive=gmail.com@vger.kernel.org" Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by am.mirrors.kernel.org (Postfix) with ESMTPS id AD18A1F24A44 for ; Thu, 11 Apr 2024 00:15:57 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DFB9847F6F; Thu, 11 Apr 2024 00:09:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b="diTtMBnK" Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9024C46B80 for ; Thu, 11 Apr 2024 00:09:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712794150; cv=none; b=jxkBQ8obkFTXY3/dnqDxyhaS231PRVlXgPA0hnvbvUGfgTCO7Zzb0vs2SaRFvZW/P3KTO75fer5vfTnkyyHXj6qHyA4KmnC62fbqZlfzJZOUyAfxPUA+TArwZJk29gEKRhzw1FsNhpE7BYFieVhU2yIuYCTl5CIrF6eUMOwEKrg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712794150; c=relaxed/simple; bh=xb672rs5EJibOYFJVRiF/hfLQII8MwUbiEEA7QXjucc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=VsMJDe5Rq27WXuopX6VuEVcUFCY+6SEZH1tSmt/Iq8q24H+1PNbBiuRar7irT5pb4GAZPO7r/zvve9b7dZUA2luyUKg+nzU4cH/aOwtLfoZRM6wM7hqk5O6ufnhP/AQmXgWwFs6K33i+QmrdiNP3h4Ii6amcgFVJeudRV6bTzYs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com; spf=pass smtp.mailfrom=rivosinc.com; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b=diTtMBnK; arc=none smtp.client-ip=209.85.214.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rivosinc.com Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-1e3dda73192so31196435ad.3 for ; Wed, 10 Apr 2024 17:09:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1712794147; x=1713398947; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=CMnuEfMmhTbxsHuHfbuFwM+0a2BQQDxSVtnwpOahwcE=; b=diTtMBnK1ltNvQnlY4qWuBi/V/hPbHjF6fnEaOVVIVRIbUmdlQFUvTEWDtegXkfp/q yGP2tkPcNlQoLAz/D1fAfa2eziTzNC3OE8VI2lVnrFDx++5cp2613TmuvfVsFou1dfbV Tc1JEDEk+7+Tvr1uEgsEEnuLlbjO1um4QcpFJGqKOHlVEFYi/Zr/4PcFlfM154IsCD0N xrSzHxLuAB05C+KsHaI6jqbUxum7KCEuIznT+qqAxwMwDP/kE4BRxukTlQPY7T1IweFW byTGJ354vtlNR2fpB+J+gAUMHlDX/heNqxN+pK700PdRW2UIEUt+g2ZAZ0QFoog0uc3z 5PoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712794147; x=1713398947; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CMnuEfMmhTbxsHuHfbuFwM+0a2BQQDxSVtnwpOahwcE=; b=JjIKLTY4LpjTYmKyCm2o2JWddmBKb4sCsKlyQ65YdSpnMJiXZMJuBwoIXRxFLHiE6Y h9k/Z4Qjv/CixY6eDOLMv1AcHxjz3feJHODmDMDHMvk5IvU0UUzuJNWUFJ0AjnhYA5J/ SgEL+wj6KTcSEIAsjN4vBb/BOaCbPxGmDXXekyG73MjcPL62Z4cf4embGAaue9iIHBEP sQNJSlnC6cYUuCpKG55vl0QpDi1J9WvDWDrCVxW6aQJT83V+Dd/8fe/h8226kL/VNAJc cIu1sEoOoraHs0HHeUWw6oGlMFfsudVdt3lklrw47p4drx/OC+vcCDKsSJ+2J0gIDfqr +k1w== X-Gm-Message-State: AOJu0YwPfGmH1z1Ue4bAns+Wj7OECvcSlcytwvPI6Xfs6ZgzfSHJ9te6 myV95dCHD6tHTUZYZfo9d6EpPvTE8S6iwZhsGZZmf7bQ7edJFjdSeF+EWiwpT3XSloJTvVjDs/e q X-Received: by 2002:a17:902:d511:b0:1e0:b62a:c0a2 with SMTP id b17-20020a170902d51100b001e0b62ac0a2mr5132273plg.51.1712794147134; Wed, 10 Apr 2024 17:09:07 -0700 (PDT) Received: from atishp.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id f7-20020a170902684700b001e3d8a70780sm130351pln.171.2024.04.10.17.09.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Apr 2024 17:09:05 -0700 (PDT) From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Andrew Jones , Anup Patel , Ajay Kaher , Albert Ou , Alexandre Ghiti , Alexey Makhalov , Atish Patra , Broadcom internal kernel review list , Conor Dooley , Juergen Gross , kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-riscv@lists.infradead.org, Mark Rutland , Palmer Dabbelt , Paolo Bonzini , Paul Walmsley , Shuah Khan , virtualization@lists.linux.dev, Will Deacon , x86@kernel.org Subject: [PATCH v6 22/24] KVM: riscv: selftests: Add a test for PMU snapshot functionality Date: Wed, 10 Apr 2024 17:07:50 -0700 Message-Id: <20240411000752.955910-23-atishp@rivosinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240411000752.955910-1-atishp@rivosinc.com> References: <20240411000752.955910-1-atishp@rivosinc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Verify PMU snapshot functionality by setting up the shared memory correctly and reading the counter values from the shared memory instead of the CSR. Reviewed-by: Andrew Jones Reviewed-by: Anup Patel Signed-off-by: Atish Patra --- .../testing/selftests/kvm/include/riscv/sbi.h | 25 +++ .../selftests/kvm/lib/riscv/processor.c | 12 ++ .../selftests/kvm/riscv/sbi_pmu_test.c | 144 ++++++++++++++++++ 3 files changed, 181 insertions(+) diff --git a/tools/testing/selftests/kvm/include/riscv/sbi.h b/tools/testing/selftests/kvm/include/riscv/sbi.h index 6675ca673c77..1b995481a3fa 100644 --- a/tools/testing/selftests/kvm/include/riscv/sbi.h +++ b/tools/testing/selftests/kvm/include/riscv/sbi.h @@ -8,6 +8,12 @@ #ifndef SELFTEST_KVM_SBI_H #define SELFTEST_KVM_SBI_H +/* SBI spec version fields */ +#define SBI_SPEC_VERSION_DEFAULT 0x1 +#define SBI_SPEC_VERSION_MAJOR_SHIFT 24 +#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f +#define SBI_SPEC_VERSION_MINOR_MASK 0xffffff + /* SBI return error codes */ #define SBI_SUCCESS 0 #define SBI_ERR_FAILURE -1 @@ -33,6 +39,9 @@ enum sbi_ext_id { }; enum sbi_ext_base_fid { + SBI_EXT_BASE_GET_SPEC_VERSION = 0, + SBI_EXT_BASE_GET_IMP_ID, + SBI_EXT_BASE_GET_IMP_VERSION, SBI_EXT_BASE_PROBE_EXT = 3, }; enum sbi_ext_pmu_fid { @@ -60,6 +69,12 @@ union sbi_pmu_ctr_info { }; }; +struct riscv_pmu_snapshot_data { + u64 ctr_overflow_mask; + u64 ctr_values[64]; + u64 reserved[447]; +}; + struct sbiret { long error; long value; @@ -113,4 +128,14 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, bool guest_sbi_probe_extension(int extid, long *out_val); +/* Make SBI version */ +static inline unsigned long sbi_mk_version(unsigned long major, + unsigned long minor) +{ + return ((major & SBI_SPEC_VERSION_MAJOR_MASK) << SBI_SPEC_VERSION_MAJOR_SHIFT + | (minor & SBI_SPEC_VERSION_MINOR_MASK)); +} + +unsigned long get_host_sbi_spec_version(void); + #endif /* SELFTEST_KVM_SBI_H */ diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c index e8211f5d6863..ccb35573749c 100644 --- a/tools/testing/selftests/kvm/lib/riscv/processor.c +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c @@ -502,3 +502,15 @@ bool guest_sbi_probe_extension(int extid, long *out_val) return true; } + +unsigned long get_host_sbi_spec_version(void) +{ + struct sbiret ret; + + ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION, 0, + 0, 0, 0, 0, 0); + + GUEST_ASSERT(!ret.error); + + return ret.value; +} diff --git a/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c b/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c index 7c81691e39c5..9002ff451abf 100644 --- a/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c +++ b/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c @@ -19,6 +19,11 @@ #define RISCV_MAX_PMU_COUNTERS 64 union sbi_pmu_ctr_info ctrinfo_arr[RISCV_MAX_PMU_COUNTERS]; +/* Snapshot shared memory data */ +#define PMU_SNAPSHOT_GPA_BASE BIT(30) +static void *snapshot_gva; +static vm_paddr_t snapshot_gpa; + /* Cache the available counters in a bitmask */ static unsigned long counter_mask_available; @@ -186,6 +191,32 @@ static unsigned long read_counter(int idx, union sbi_pmu_ctr_info ctrinfo) return counter_val; } +static inline void verify_sbi_requirement_assert(void) +{ + long out_val = 0; + bool probe; + + probe = guest_sbi_probe_extension(SBI_EXT_PMU, &out_val); + GUEST_ASSERT(probe && out_val == 1); + + if (get_host_sbi_spec_version() < sbi_mk_version(2, 0)) + __GUEST_ASSERT(0, "SBI implementation version doesn't support PMU Snapshot"); +} + +static void snapshot_set_shmem(vm_paddr_t gpa, unsigned long flags) +{ + unsigned long lo = (unsigned long)gpa; +#if __riscv_xlen == 32 + unsigned long hi = (unsigned long)(gpa >> 32); +#else + unsigned long hi = gpa == -1 ? -1 : 0; +#endif + struct sbiret ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_SNAPSHOT_SET_SHMEM, + lo, hi, flags, 0, 0, 0); + + GUEST_ASSERT(ret.value == 0 && ret.error == 0); +} + static void test_pmu_event(unsigned long event) { unsigned long counter; @@ -234,6 +265,59 @@ static void test_pmu_event(unsigned long event) stop_reset_counter(counter, 0); } +static void test_pmu_event_snapshot(unsigned long event) +{ + unsigned long counter; + unsigned long counter_value_pre, counter_value_post; + unsigned long counter_init_value = 100; + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; + + counter = get_counter_index(0, counter_mask_available, 0, event); + counter_value_pre = read_counter(counter, ctrinfo_arr[counter]); + + /* Do not set the initial value */ + start_counter(counter, 0, 0); + dummy_func_loop(10000); + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); + + /* The counter value is updated w.r.t relative index of cbase */ + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); + __GUEST_ASSERT(counter_value_post > counter_value_pre, + "Event update verification failed: post [%lx] pre [%lx]\n", + counter_value_post, counter_value_pre); + + /* + * We can't just update the counter without starting it. + * Do start/stop twice to simulate that by first initializing to a very + * high value and a low value after that. + */ + WRITE_ONCE(snapshot_data->ctr_values[0], ULONG_MAX/2); + start_counter(counter, SBI_PMU_START_FLAG_INIT_SNAPSHOT, 0); + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); + counter_value_pre = READ_ONCE(snapshot_data->ctr_values[0]); + + WRITE_ONCE(snapshot_data->ctr_values[0], counter_init_value); + start_counter(counter, SBI_PMU_START_FLAG_INIT_SNAPSHOT, 0); + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); + __GUEST_ASSERT(counter_value_pre > counter_value_post, + "Counter reinitialization verification failed : post [%lx] pre [%lx]\n", + counter_value_post, counter_value_pre); + + /* Now set the initial value and compare */ + WRITE_ONCE(snapshot_data->ctr_values[0], counter_init_value); + start_counter(counter, SBI_PMU_START_FLAG_INIT_SNAPSHOT, 0); + dummy_func_loop(10000); + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); + + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); + __GUEST_ASSERT(counter_value_post > counter_init_value, + "Event update verification failed: post [%lx] pre [%lx]\n", + counter_value_post, counter_init_value); + + stop_reset_counter(counter, 0); +} + static void test_invalid_event(void) { struct sbiret ret; @@ -301,6 +385,34 @@ static void test_pmu_basic_sanity(void) GUEST_DONE(); } +static void test_pmu_events_snaphost(void) +{ + int num_counters = 0; + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; + int i; + + /* Verify presence of SBI PMU and minimum requrired SBI version */ + verify_sbi_requirement_assert(); + + snapshot_set_shmem(snapshot_gpa, 0); + + /* Get the counter details */ + num_counters = get_num_counters(); + update_counter_info(num_counters); + + /* Validate shared memory access */ + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_overflow_mask), 0); + for (i = 0; i < num_counters; i++) { + if (counter_mask_available & (BIT(i))) + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_values[i]), 0); + } + /* Only these two events are guranteed to be present */ + test_pmu_event_snapshot(SBI_PMU_HW_CPU_CYCLES); + test_pmu_event_snapshot(SBI_PMU_HW_INSTRUCTIONS); + + GUEST_DONE(); +} + static void run_vcpu(struct kvm_vcpu *vcpu) { struct ucall uc; @@ -357,6 +469,35 @@ static void test_vm_events_test(void *guest_code) test_vm_destroy(vm); } +static void test_vm_setup_snapshot_mem(struct kvm_vm *vm, struct kvm_vcpu *vcpu) +{ + /* PMU Snapshot requires single page only */ + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, PMU_SNAPSHOT_GPA_BASE, 1, 1, 0); + /* PMU_SNAPSHOT_GPA_BASE is identity mapped */ + virt_map(vm, PMU_SNAPSHOT_GPA_BASE, PMU_SNAPSHOT_GPA_BASE, 1); + + snapshot_gva = (void *)(PMU_SNAPSHOT_GPA_BASE); + snapshot_gpa = addr_gva2gpa(vcpu->vm, (vm_vaddr_t)snapshot_gva); + sync_global_to_guest(vcpu->vm, snapshot_gva); + sync_global_to_guest(vcpu->vm, snapshot_gpa); +} + +static void test_vm_events_snapshot_test(void *guest_code) +{ + struct kvm_vm *vm = NULL; + struct kvm_vcpu *vcpu; + + vm = vm_create_with_one_vcpu(&vcpu, guest_code); + __TEST_REQUIRE(__vcpu_has_sbi_ext(vcpu, KVM_RISCV_SBI_EXT_PMU), + "SBI PMU not available, skipping test"); + + test_vm_setup_snapshot_mem(vm, vcpu); + + run_vcpu(vcpu); + + test_vm_destroy(vm); +} + int main(void) { test_vm_basic_test(test_pmu_basic_sanity); @@ -365,5 +506,8 @@ int main(void) test_vm_events_test(test_pmu_events); pr_info("SBI PMU event verification test : PASS\n"); + test_vm_events_snapshot_test(test_pmu_events_snaphost); + pr_info("SBI PMU event verification with snapshot test : PASS\n"); + return 0; } -- 2.34.1