From patchwork Tue Mar 5 06:43:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 13581699 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-oi1-f174.google.com (mail-oi1-f174.google.com [209.85.167.174]) (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 C5E631EA6F for ; Tue, 5 Mar 2024 06:44:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.174 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709621049; cv=none; b=cNK/N97TNzasP3sulbvFflJjBJBbTttyFz+PoE0kfb6LNt9o3XUjX7nej5HLtgw8kmcwageAtzjAYzvPzLbOns0KwUc0lYTJhCcFPYHLB1m9K+thpjliPNt6np0tt1CRwBHQzXGLnWLFSTwEqcr2edf+jKwGAC0xaVv2pz8bAJw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709621049; c=relaxed/simple; bh=mf8yMKZPIxIbiyH0ekDAI1hMR9qnE76DYdITOuowuq4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=d/geFf3k9f6oexkY6jfmgQjIPGMXKJAoKmJloPJcw01t0WaoapE3xONzwYjX6SgKRevordK8LRkKCbUhmkTY86hImpqCTKOJqm1K1rwQphuGFKmrDCS5nwddo2VR1or08f7KWtHRtXdwCbf9Rur/AlUWU86TkaegpRoHQSVvxV8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Hrxa2ti9; arc=none smtp.client-ip=209.85.167.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Hrxa2ti9" Received: by mail-oi1-f174.google.com with SMTP id 5614622812f47-3c1ea5b42e7so1325109b6e.2 for ; Mon, 04 Mar 2024 22:44:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1709621046; x=1710225846; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=U9oDnqtMY2zxNPWuO0M89IcTSHoNEb5Q5xdDMziT6o4=; b=Hrxa2ti9euHiPU62+RhtdaeDV/holSlTkLC0BSfWk7Tq92nfGO8WbTPQx55CJmN3Ei 99dNa2xf8VilnK1Pr/up42ykWuWYG4LyCWYIikdxV4BfDcKsk5sd2W3oHl46CEtpvlxE hisc9PAfHjWBYR3ITNKzdRmFPI/pdQqkAmpT6kYr0rCJ8AY0ux8AjWSb8qfaBFY86+6m kH3SqhzCP9jsPRc1machMOOOq2eCi2DeDQB5GmJXMkyDNGG4QKxoXX/+4NzCFXjD2N8+ U5009EfWxobgi5uiX3wfjoYpTpECzKt/CMPO6Xl+3kNU1AI1yiLRm0Y0eMmBGESaAnxI 09JQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709621046; x=1710225846; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=U9oDnqtMY2zxNPWuO0M89IcTSHoNEb5Q5xdDMziT6o4=; b=YTTRZxF9TVra0h6jVK7+vsi0s9+CozCSja7WNTKjKW3koFPfxcXaJSlrAau7OwY79+ ffswQ4MGHTGiie4swnvmw2t5YJhttvyCk8Q+B1h2eUaXYB+IwiY0+UGsc6//IC0mI6C7 ZuXRiOUefS5YVTgOiKZ/bPQ4U7iL3T6AkyaV7n9NO+x92AjDQ9pbrjmjmvQ9ElHUnJqZ lrq4ESr5zrMlX5Qfy023p6BVuDj7VjN3QlxJqbtaRaMU9aQg/IA1B8V+bL8uKKaFQ2/Z UVN5O9ubFry/dkZtM89x5tx+XOiZlIwgEvJZ78tVwusZTjG6PaPB1zli5AciwTquJMYN K2mA== X-Gm-Message-State: AOJu0YyR6ARD30ZmUX/LZQVufuJZQYdylnJydfOY2FsT7e+Bg4os8yLr T7GHg/JFtb+pzgPnB7t1jkPmeJWO6cuTFhC6pHjVffD7+TA+qOME X-Google-Smtp-Source: AGHT+IGx6+1/o1ZJJwOxzweC3Ne6bhGqFWJ8xrIy1y68u3/v4yNIJFii9awfkJ1M4ZnjoSu1z18A/w== X-Received: by 2002:aca:2214:0:b0:3c1:7d8d:29b9 with SMTP id b20-20020aca2214000000b003c17d8d29b9mr1017553oic.21.1709621045654; Mon, 04 Mar 2024 22:44:05 -0800 (PST) Received: from localhost.localdomain ([39.144.105.163]) by smtp.gmail.com with ESMTPSA id j36-20020a63fc24000000b0059b2316be86sm8345831pgi.46.2024.03.04.22.44.00 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Mar 2024 22:44:05 -0800 (PST) From: Yafang Shao To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Cc: bpf@vger.kernel.org, Yafang Shao Subject: [PATCH v3 bpf-next 1/2] bpf: Add bits iterator Date: Tue, 5 Mar 2024 14:43:52 +0800 Message-Id: <20240305064353.69734-1-laoar.shao@gmail.com> X-Mailer: git-send-email 2.30.1 (Apple Git-130) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net Add three new kfuncs for the bits iterator: - bpf_iter_bits_new Initialize a new bits iterator for a given memory area. Due to the limitation of bpf memalloc, the max number of bits that can be iterated over is limited to (4096 * 8). - bpf_iter_bits_next Get the next bit in a bpf_iter_bits - bpf_iter_bits_destroy Destroy a bpf_iter_bits The bits iterator facilitates the iteration of the bits of a memory area, such as cpumask. It can be used in any context and on any address. Signed-off-by: Yafang Shao --- kernel/bpf/helpers.c | 117 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index a89587859571..a769561b65ae 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -2545,6 +2545,120 @@ __bpf_kfunc void bpf_throw(u64 cookie) WARN(1, "A call to BPF exception callback should never return\n"); } +struct bpf_iter_bits { + __u64 __opaque[2]; +} __aligned(8); + +struct bpf_iter_bits_kern { + union { + unsigned long *bits; + unsigned long bits_copy; + }; + u32 nr_bits; + int bit; +} __aligned(8); + +/** + * bpf_iter_bits_new() - Initialize a new bits iterator for a given memory area + * @it: The new bpf_iter_bits to be created + * @unsafe_ptr__ign: A ponter pointing to a memory area to be iterated over + * @nr_bits: The number of bits to be iterated over. Due to the limitation of + * memalloc, it can't greater than (4096 * 8). + * + * This function initializes a new bpf_iter_bits structure for iterating over + * a memory area which is specified by the @unsafe_ptr__ign and @nr_bits. It + * copy the data of the memory area to the newly created bpf_iter_bits @it for + * subsequent iteration operations. + * + * On success, 0 is returned. On failure, ERR is returned. + */ +__bpf_kfunc int +bpf_iter_bits_new(struct bpf_iter_bits *it, const void *unsafe_ptr__ign, u32 nr_bits) +{ + struct bpf_iter_bits_kern *kit = (void *)it; + u32 size = BITS_TO_BYTES(nr_bits); + int err; + + BUILD_BUG_ON(sizeof(struct bpf_iter_bits_kern) != sizeof(struct bpf_iter_bits)); + BUILD_BUG_ON(__alignof__(struct bpf_iter_bits_kern) != + __alignof__(struct bpf_iter_bits)); + + if (!unsafe_ptr__ign || !nr_bits) { + kit->bits = NULL; + return -EINVAL; + } + + kit->nr_bits = 0; + /* Optimization for u64/u32 mask */ + if (nr_bits <= 64) { + err = bpf_probe_read_kernel_common(&kit->bits_copy, size, unsafe_ptr__ign); + if (unlikely(err)) + return -EFAULT; + + kit->nr_bits = nr_bits; + kit->bit = -1; + return 0; + } + + /* Fallback to memalloc */ + kit->bits = bpf_mem_alloc(&bpf_global_ma, size); + if (!kit->bits) + return -ENOMEM; + + err = bpf_probe_read_kernel_common(kit->bits, size, unsafe_ptr__ign); + if (err) { + bpf_mem_free(&bpf_global_ma, kit->bits); + return err; + } + + kit->nr_bits = nr_bits; + kit->bit = -1; + return 0; +} + +/** + * bpf_iter_bits_next() - Get the next bit in a bpf_iter_bits + * @it: The bpf_iter_bits to be checked + * + * This function returns a pointer to a number representing the value of the + * next bit in the bits. + * + * If there are no further bit available, it returns NULL. + */ +__bpf_kfunc int *bpf_iter_bits_next(struct bpf_iter_bits *it) +{ + struct bpf_iter_bits_kern *kit = (void *)it; + u32 nr_bits = kit->nr_bits; + const unsigned long *bits; + int bit; + + if (nr_bits == 0) + return NULL; + + bits = nr_bits <= 64 ? &kit->bits_copy : kit->bits; + bit = find_next_bit(bits, kit->nr_bits, kit->bit + 1); + if (bit >= kit->nr_bits) + return NULL; + + kit->bit = bit; + return &kit->bit; +} + +/** + * bpf_iter_bits_destroy() - Destroy a bpf_iter_bits + * @it: The bpf_iter_bits to be destroyed + * + * Destroy the resource associated with the bpf_iter_bits. + */ +__bpf_kfunc void bpf_iter_bits_destroy(struct bpf_iter_bits *it) +{ + struct bpf_iter_bits_kern *kit = (void *)it; + + if (kit->nr_bits <= 64) + return; + bpf_mem_free(&bpf_global_ma, kit->bits); +} + __bpf_kfunc_end_defs(); BTF_KFUNCS_START(generic_btf_ids) @@ -2621,6 +2735,9 @@ BTF_ID_FLAGS(func, bpf_dynptr_is_null) BTF_ID_FLAGS(func, bpf_dynptr_is_rdonly) BTF_ID_FLAGS(func, bpf_dynptr_size) BTF_ID_FLAGS(func, bpf_dynptr_clone) +BTF_ID_FLAGS(func, bpf_iter_bits_new, KF_ITER_NEW) +BTF_ID_FLAGS(func, bpf_iter_bits_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_bits_destroy, KF_ITER_DESTROY) BTF_KFUNCS_END(common_btf_ids) static const struct btf_kfunc_id_set common_kfunc_set = { From patchwork Tue Mar 5 06:43:53 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 13581700 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-oi1-f181.google.com (mail-oi1-f181.google.com [209.85.167.181]) (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 085021EA6F for ; Tue, 5 Mar 2024 06:44:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.181 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709621053; cv=none; b=dsDD9Ko08AP2Lqk9bW6jnNGOgW+f6tw9gK3YqFSv0yuYUycY7JNlAJCRm1UuytBlqrOBOmUl2HNrcASSfxV+uM1yZ6PTIR7/Krm167yJ+vBURZsiNh+ccnz/FlCRf9bBYqJhTlBGVYJdbZeYKTGU83da4TOuKTpuH8tOkHdOWXg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709621053; c=relaxed/simple; bh=2ZkgGcqwIJgKudIKhvY2dg+3OfK9dMOeN0Scc2VOwgM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=EWMcl8vOyky5qq+WOCsYdcozaH8RrtRWxMIFGjwdYH9AFOjX8nYpk5ddMLscbJoaayYecbOttM2MKyq+23Obep/L15woEv/Ear8p3W4Z5hkt/Qg+slhPMEO2cXNH3WmdwNiI74e/2Z5jLRkeFKJ6GSZHF+rB++SpXt8/LqC/rAE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=f/OZAhRl; arc=none smtp.client-ip=209.85.167.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="f/OZAhRl" Received: by mail-oi1-f181.google.com with SMTP id 5614622812f47-3c1a2f7e1d2so3013079b6e.1 for ; Mon, 04 Mar 2024 22:44:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1709621051; x=1710225851; 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=JhWCQLvNX/WDOpuHateipLaz7F1iVqsaFY5KACk/SZU=; b=f/OZAhRly6xNaxMDkvyrabqdj2sBNasVKUljrqRy2S9Bc9cGsKzjKjjHZKYOaKO/BW ydOT4LLRxcTQr+lDY7TRztpF4RwL+0Yd3YmdrlYOarJ10jquaV9ic9ljvHbsrYvwl0Xa W9fkqEYWt5RLeyfFaBGiqW8Gm7NhLgEurk+k0sSxpmMBb/CUsywG1g+579hcezVuZn53 yLxvyBgHkAbmrAovaftm+OnmzYfR1ohgYINv2QKdCU3R7H43Mo7WmzptnohkwLR/m2hT 0cyTO0JQHYKvlMmTnaVufhV45k85BJLFDSQTZ1p0JOCQD2FfBqF5tBchm4Z74LvBF7w7 G5eA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709621051; x=1710225851; 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=JhWCQLvNX/WDOpuHateipLaz7F1iVqsaFY5KACk/SZU=; b=JoqFsYSpVjW4wKywfCsq8bWnf2tinZO7VR40BEAJ/0PuGK1d9qjHJPsYvQteoD/Dxc TF4MXFKiBUGrbv4w9UBNwD4V5yLCcNcNvT5sPzKXpyRDf+mvoLii8dsqaUBtLl2Mydn2 ajXRrt3v/Cv1z9WVXDS54eaXKnRqfoWi8LfvI0eeQAiRCIj0VDOjVIo6pTw9whPFaA5c kRo8/c3Mymgpmo5IgKZXU91TfsZeVgOSQZ0VhPNsKMXGOBP9DRDRomr/5Wjm97K5QLcD DI0KRvo4ysXFxsjNcn0X2kUAEZgnz7ZTDYDDoxC0H2yUv0VBtRUR+suRU+1veO/6E0OO rjBA== X-Gm-Message-State: AOJu0YzN/Ukv6onVGnwayOI1uIi8xOUy/pWQmEq6egIjXPEg4B2ipKHu 5fU7Qnd9QQKkzs0RGLRdRUi18QgQMdWLu0GN3Bo3YD9dG2jQQW4J5FFIZUlihxVyjg== X-Google-Smtp-Source: AGHT+IGmRCfx3ep362enrspTPx0PkrCc/NNJy55rZ9Jv4pDnIaAsgUfdJ5mNgnq2nRcCWZ+zCfAZag== X-Received: by 2002:aca:1717:0:b0:3c1:c36e:9ec9 with SMTP id j23-20020aca1717000000b003c1c36e9ec9mr995277oii.17.1709621051150; Mon, 04 Mar 2024 22:44:11 -0800 (PST) Received: from localhost.localdomain ([39.144.105.163]) by smtp.gmail.com with ESMTPSA id j36-20020a63fc24000000b0059b2316be86sm8345831pgi.46.2024.03.04.22.44.05 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Mar 2024 22:44:10 -0800 (PST) From: Yafang Shao To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Cc: bpf@vger.kernel.org, Yafang Shao Subject: [PATCH v3 bpf-next 2/2] selftests/bpf: Add selftest for bits iter Date: Tue, 5 Mar 2024 14:43:53 +0800 Message-Id: <20240305064353.69734-2-laoar.shao@gmail.com> X-Mailer: git-send-email 2.30.1 (Apple Git-130) In-Reply-To: <20240305064353.69734-1-laoar.shao@gmail.com> References: <20240305064353.69734-1-laoar.shao@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net Add selftests for the newly added bits iter. - bits_iter_success - percpu data extracted from the percpu struct should be expected - RCU lock is not required - It is fine without calling bpf_iter_cpumask_next() - It can work as expected when invalid arguments are passed - bits_iter_failure - bpf_iter_bits_destroy() is required after calling bpf_iter_bits_new() - bpf_iter_bits_destroy() can only destroy an initialized iter - bpf_iter_bits_next() must use an initialized iter This test case can't work correctly on s390x for unknonw reason, thus it is added to DENYLIST.s390x. Signed-off-by: Yafang Shao --- tools/testing/selftests/bpf/DENYLIST.s390x | 3 +- .../selftests/bpf/prog_tests/bits_iter.c | 137 ++++++++++++++++++ .../bpf/progs/test_bits_iter_failure.c | 54 +++++++ .../bpf/progs/test_bits_iter_success.c | 122 ++++++++++++++++ 4 files changed, 315 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/bits_iter.c create mode 100644 tools/testing/selftests/bpf/progs/test_bits_iter_failure.c create mode 100644 tools/testing/selftests/bpf/progs/test_bits_iter_success.c diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x b/tools/testing/selftests/bpf/DENYLIST.s390x index 1a63996c0304..0cd6d2bf1ff4 100644 --- a/tools/testing/selftests/bpf/DENYLIST.s390x +++ b/tools/testing/selftests/bpf/DENYLIST.s390x @@ -1,5 +1,6 @@ # TEMPORARY # Alphabetical order -exceptions # JIT does not support calling kfunc bpf_throw (exceptions) +bits_iter # cpumask iter can't work as expected (?) +exceptions # JIT does not support calling kfunc bpf_throw (exceptions) get_stack_raw_tp # user_stack corrupted user stack (no backchain userspace) stacktrace_build_id # compare_map_keys stackid_hmap vs. stackmap err -2 errno 2 (?) diff --git a/tools/testing/selftests/bpf/prog_tests/bits_iter.c b/tools/testing/selftests/bpf/prog_tests/bits_iter.c new file mode 100644 index 000000000000..ff4f921c91c9 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/bits_iter.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2024 Yafang Shao */ + +#define _GNU_SOURCE +#include + +#include +#include "test_bits_iter_success.skel.h" +#include "test_bits_iter_failure.skel.h" +#include "cgroup_helpers.h" + +static const char * const positive_testcases[] = { + "cpumask_memalloc", + "cpumask_copy", +}; + +static const char * const negative_testcases[] = { + "null_pointer", + "zero_bit", + "no_mem", +}; + +static int read_percpu_data(struct bpf_link *link) +{ + int iter_fd, len; + char buf[128]; + size_t left; + char *p; + + iter_fd = bpf_iter_create(bpf_link__fd(link)); + if (!ASSERT_GE(iter_fd, 0, "iter_fd")) + return -1; + + memset(buf, 0, sizeof(buf)); + left = ARRAY_SIZE(buf); + p = buf; + while ((len = read(iter_fd, p, left)) > 0) { + p += len; + left -= len; + } + + close(iter_fd); + return 0; +} + +static void verify_iter_success(const char *prog_name, bool negative) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + struct test_bits_iter_success *skel; + union bpf_iter_link_info linfo; + int cgrp_fd, err, i, nr_cpus; + struct bpf_program *prog; + struct bpf_link *link; + cpu_set_t set; + + if (setup_cgroup_environment()) + return; + + /* Utilize the cgroup iter */ + cgrp_fd = get_root_cgroup(); + if (!ASSERT_GE(cgrp_fd, 0, "create_cgrp")) + goto cleanup; + + skel = test_bits_iter_success__open(); + if (!ASSERT_OK_PTR(skel, "cpumask_iter_success__open")) + goto close_fd; + + skel->bss->pid = getpid(); + + err = test_bits_iter_success__load(skel); + if (!ASSERT_OK(err, "cpumask_iter_success__load")) + goto destroy; + + prog = bpf_object__find_program_by_name(skel->obj, prog_name); + if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name")) + goto destroy; + + memset(&linfo, 0, sizeof(linfo)); + linfo.cgroup.cgroup_fd = cgrp_fd; + linfo.cgroup.order = BPF_CGROUP_ITER_SELF_ONLY; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + link = bpf_program__attach_iter(prog, &opts); + if (!ASSERT_OK_PTR(link, "bpf_program__attach")) + goto destroy; + + if (negative) + goto negative; + + CPU_ZERO(&set); + nr_cpus = libbpf_num_possible_cpus(); + /* To guarantee the success of "cpumask_copy" at all times */ + if (nr_cpus > 16) + nr_cpus = 16; + for (i = 0; i < nr_cpus; i++) + CPU_SET(i, &set); + err = sched_setaffinity(skel->bss->pid, sizeof(set), &set); + if (!ASSERT_OK(err, "setaffinity_all_cpus")) + goto free_link; + err = read_percpu_data(link); + if (!ASSERT_OK(err, "read_percpu_data")) + goto free_link; + +negative: + ASSERT_OK(skel->bss->err, "not_zero"); + +free_link: + bpf_link__destroy(link); +destroy: + test_bits_iter_success__destroy(skel); +close_fd: + close(cgrp_fd); +cleanup: + cleanup_cgroup_environment(); +} + +void test_bits_iter(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(positive_testcases); i++) { + if (!test__start_subtest(positive_testcases[i])) + continue; + + verify_iter_success(positive_testcases[i], false); + } + + for (i = 0; i < ARRAY_SIZE(negative_testcases); i++) { + if (!test__start_subtest(negative_testcases[i])) + continue; + + verify_iter_success(negative_testcases[i], true); + } + + RUN_TESTS(test_bits_iter_success); + RUN_TESTS(test_bits_iter_failure); +} diff --git a/tools/testing/selftests/bpf/progs/test_bits_iter_failure.c b/tools/testing/selftests/bpf/progs/test_bits_iter_failure.c new file mode 100644 index 000000000000..974d0b7a540e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_bits_iter_failure.c @@ -0,0 +1,54 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2024 Yafang Shao */ + +#include "vmlinux.h" +#include +#include + +#include "bpf_misc.h" +#include "task_kfunc_common.h" + +char _license[] SEC("license") = "GPL"; + +int bpf_iter_bits_new(struct bpf_iter_bits *it, const void *unsafe_ptr__ign, + u32 nr_bits) __ksym __weak; +int *bpf_iter_bits_next(struct bpf_iter_bits *it) __ksym __weak; +void bpf_iter_bits_destroy(struct bpf_iter_bits *it) __ksym __weak; + +SEC("iter.s/cgroup") +__failure __msg("Unreleased reference id=3 alloc_insn=10") +int BPF_PROG(no_destroy, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_bits it; + struct task_struct *p; + + p = bpf_task_from_pid(1); + if (!p) + return 1; + + bpf_iter_bits_new(&it, p->cpus_ptr, 8192); + + bpf_iter_bits_next(&it); + bpf_task_release(p); + return 0; +} + +SEC("iter/cgroup") +__failure __msg("expected an initialized iter_bits as arg #1") +int BPF_PROG(next_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_bits *it = NULL; + + bpf_iter_bits_next(it); + return 0; +} + +SEC("iter/cgroup") +__failure __msg("expected an initialized iter_bits as arg #1") +int BPF_PROG(destroy_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_bits it = {}; + + bpf_iter_bits_destroy(&it); + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/test_bits_iter_success.c b/tools/testing/selftests/bpf/progs/test_bits_iter_success.c new file mode 100644 index 000000000000..77081204dec3 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_bits_iter_success.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2024 Yafang Shao */ + +#include "vmlinux.h" +#include +#include +#include + +#include "task_kfunc_common.h" + +char _license[] SEC("license") = "GPL"; + +extern const struct rq runqueues __ksym __weak; + +int bpf_iter_bits_new(struct bpf_iter_bits *it, const void *unsafe_ptr__ign, + u32 nr_bits) __ksym __weak; +int *bpf_iter_bits_next(struct bpf_iter_bits *it) __ksym __weak; +void bpf_iter_bits_destroy(struct bpf_iter_bits *it) __ksym __weak; + +int pid, err; + +static int cpumask_iter(struct bpf_iter_meta *meta, struct cgroup *cgrp, u32 nr_cpus) +{ + struct task_struct *p; + u32 nr_running = 0; + struct rq *rq; + int *cpu; + + /* epilogue */ + if (!cgrp) + return 0; + + p = bpf_task_from_pid(pid); + if (!p) + return 1; + + bpf_for_each(bits, cpu, p->cpus_ptr, nr_cpus) { + rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, *cpu); + /* Every valid CPU should possess a runqueue, even in the event of being offline */ + if (!rq) + break; + nr_running += rq->nr_running; + } + if (nr_running == 0) + err = 1; + bpf_task_release(p); + return 0; +} + +SEC("iter.s/cgroup") +int BPF_PROG(cpumask_memalloc, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + return cpumask_iter(meta, cgrp, 128); +} + +SEC("iter.s/cgroup") +int BPF_PROG(cpumask_copy, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + return cpumask_iter(meta, cgrp, 16); +} + +SEC("iter.s/cgroup") +int BPF_PROG(null_pointer, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + int *cpu; + + bpf_for_each(bits, cpu, NULL, 8192) + err++; + return 0; +} + +SEC("iter.s/cgroup") +int BPF_PROG(zero_bit, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct task_struct *p; + int *cpu; + + p = bpf_task_from_pid(pid); + if (!p) + return 1; + + bpf_for_each(bits, cpu, p->cpus_ptr, 0) + err++; + bpf_task_release(p); + return 0; +} + +SEC("iter.s/cgroup") +int BPF_PROG(no_mem, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct task_struct *p; + int *cpu; + + p = bpf_task_from_pid(pid); + if (!p) + return 1; + + /* The max number of memalloc is 4096, thus it will fail to allocate (8192 * 8) */ + bpf_for_each(bits, cpu, p->cpus_ptr, 8192 * 8) + err++; + bpf_task_release(p); + return 0; +} + +SEC("iter.s/cgroup") +int BPF_PROG(no_next, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_bits it; + struct task_struct *p; + + p = bpf_task_from_pid(1); + if (!p) + return 1; + + bpf_iter_bits_new(&it, p->cpus_ptr, 8192); + + /* It functions properly without invoking bpf_iter_bits_next(). */ + + bpf_iter_bits_destroy(&it); + bpf_task_release(p); + return 0; +}