From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f177.google.com (mail-pg1-f177.google.com [209.85.215.177]) (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 6D33C3BB124 for ; Thu, 18 Jun 2026 08:56:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781773000; cv=none; b=eAdlgEh7B58yVLQzQ1T7Xt9EsSillkBVHCtOac+jIzbWfhljux350hKVViBVrn+ReoSUEjWZjQjZCCB5x6sVMTxHruRvhymi1yhoQ2EeLloRdT6KEuR1Nnf4RHgWhoq3NV1l88ODjssTfqxtiV4f/uRF7LVNUOYl/FIu2RoPfDY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781773000; c=relaxed/simple; bh=73Y/6hCSCK84WGOHoIAZv2AtXpAnbJwogsMWt/xVjG4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ATJ3cbphtgDzVIjm98zhaNwWC4mKYCKYno8zO0TgYiEx1QSqsgEZsXrezR95CAppiYjavuImWO0jiFqkf8i/vwqpL+59ibuPja0zDeScBGt3rt4zTMNAbyz1XwDQ8OzgB0vzV08SzGw1pdxK4KO2kbnt4W0qj1fOYSZXB8evO/k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=etsalapatis.com; spf=pass smtp.mailfrom=etsalapatis.com; dkim=pass (2048-bit key) header.d=etsalapatis-com.20251104.gappssmtp.com header.i=@etsalapatis-com.20251104.gappssmtp.com header.b=D1Q0CDZS; arc=none smtp.client-ip=209.85.215.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=etsalapatis.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=etsalapatis.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=etsalapatis-com.20251104.gappssmtp.com header.i=@etsalapatis-com.20251104.gappssmtp.com header.b="D1Q0CDZS" Received: by mail-pg1-f177.google.com with SMTP id 41be03b00d2f7-c859878eb48so284753a12.0 for ; Thu, 18 Jun 2026 01:56:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=etsalapatis-com.20251104.gappssmtp.com; s=20251104; t=1781772999; x=1782377799; 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=97gqEJoV4Gnp5D9f5pbniwJykTL6WUeuhtKnY/ofWOk=; b=D1Q0CDZSljQWs2pgFIzxLkn1ioCvyenVbdE0Hjqh0bOj3PL2btQYNaUICNRMDAQPr2 yt9ZbX5NSED8buOLdeVEdDbWFGK7wpXcO5Y5/Js8DBk7q77aUDdQ8tOhf9VmHQxXSNwe hmogF+q5YdiCHKYFCyyqcO1KK3aDGeuXOM5wv8wyBV/u3az/OmB+tLpsFB2WIKbGFtiR idY+JMxyLvRmsiBPI0kXbkMTpXm2eD9s+wUl3LUfw4oVYOHkej0eq/N1aK3Dscpik2DO R8n/+isQ206ro0oaNLm6qjulvxV4YY3jgtDxxFW9xPqf9UqJ5s8BUjuqVubewKj6a24+ ZTeg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781772999; x=1782377799; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=97gqEJoV4Gnp5D9f5pbniwJykTL6WUeuhtKnY/ofWOk=; b=HmGqUxmKEF9zLboythoErSuceuPFx4+oimOjyK23xQsKDztdrub/WON4YQhkvkhbOU OJqbfBiwSnn1W6FChOik3NX72a/P73HDSqU9k2725SBU5iJa9WWUYUZ38Mf9b+Tmrd10 OnLeOi19CZyN84tvM5c02ziW7uc6Mh6bc/BbBNu3UvREPUy+zMdGf2gTni9lBDQrecH2 cyRCFxoxGTkhnNZ5CpDmuowLF3iUDl1ch2Gjfz8BNhsoh1XO3W7YQzTxBn8elBBc8Ood QPTDNZIlKqXIEinhUmE1kouK/QoSJJxN4Ffp+YHDsttfr4MhgwculeeoDiHyvBOVCuCN gdUQ== X-Gm-Message-State: AOJu0YxJ1Z/+lIkPI+ungRCIpcmsOCkZuZnXdOZzCUFjiaf7/mUwzqdO UJjUExUgzSOwBCPdVF0PQspYidB4BMmMCUU4S6IFO1ZoKlJL/m8Yj6ztFFQEaypDpdyhIfrhdln xfdFHv3vJwg== X-Gm-Gg: Acq92OF40iJnmHRfESW6eGaxMl58b7dXdVAA/BvVWTMljVwl+h203TqJu2f5RmsUIZK VlhjoddW55jsMQAbtjWLxSzpzyY2/1E9LiMzvO/QXuObynJf5yObSpkPk/SfRIsMYZ2w+3CuaWh PM3TqZXA3DPyU0RNFRSBn82v14uQZcgdl/qWi2N9Wf/zBuCNDXKA9VsvRmMsYTBIYKNAuaFP6yY 02C41CYYHjzJIEYC3gxCX2zWA0VIyA9HYHwZjRHSqi73zu/t7NXpHIJoAQ+VzY0rHhq74ecq54r LLEkG/GBz4XqtqNSfSuN/qeAMH2xW4izIJr+LNJ//XT21eJLOi7IUXbaY8rCoPQzeVy14erHkF4 2hNHOWQi8Aqd1CjUO3IjGv5V4KJWkHRJu6nu9zMmGdKMhbfzLdJQTOqOW8oCCK6LhWbzaLQdxZK e264zOGzdR1XRqHXCQdX2fNbh7SeKHIV6VvcI28WE= X-Received: by 2002:a05:6300:6681:b0:398:7df5:2dae with SMTP id adf61e73a8af0-3b9e5517917mr3696430637.9.1781772998560; Thu, 18 Jun 2026 01:56:38 -0700 (PDT) Received: from krios (S0106d8b37028eeb5.vc.shawcable.net. [24.84.91.85]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-c88c6c2b2easm2524404a12.27.2026.06.18.01.56.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Jun 2026 01:56:38 -0700 (PDT) From: Emil Tsalapatis To: bpf@vger.kernel.org Cc: ast@kernel.org, andrii@kernel.org, memxor@gmail.com, daniel@iogearbox.net, eddyz87@gmail.com, mattbobrowski@google.com, song@kernel.org, Emil Tsalapatis Subject: [PATCH bpf-next 4/5] selftests/bpf: Add arena-based bitmap data structure Date: Thu, 18 Jun 2026 04:56:25 -0400 Message-ID: <20260618085626.19633-5-emil@etsalapatis.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260618085626.19633-1-emil@etsalapatis.com> References: <20260618085626.19633-1-emil@etsalapatis.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add an arena-based word-aligned bitmap data struture. The structure is useful as a building block, e.g., sched-ext uses it to represent cpumask structures. Signed-off-by: Emil Tsalapatis --- .../bpf/libarena/include/libarena/bitmap.h | 31 +++ .../selftests/bpf/libarena/src/bitmap.bpf.c | 191 ++++++++++++++++++ 2 files changed, 222 insertions(+) create mode 100644 tools/testing/selftests/bpf/libarena/include/libarena/bitmap.h create mode 100644 tools/testing/selftests/bpf/libarena/src/bitmap.bpf.c diff --git a/tools/testing/selftests/bpf/libarena/include/libarena/bitmap.h b/tools/testing/selftests/bpf/libarena/include/libarena/bitmap.h new file mode 100644 index 000000000000..11623a82e66a --- /dev/null +++ b/tools/testing/selftests/bpf/libarena/include/libarena/bitmap.h @@ -0,0 +1,31 @@ +#pragma once + +#define BITS_PER_BYTE 8 +#define BYTES_TO_BITS(nb) ((nb) * BITS_PER_BYTE) + +#define BITS_PER_LONG (sizeof(long) * BITS_PER_BYTE) +#define BITS_TO_LONGS(nr) (((nr) + BITS_PER_LONG - 1) / BITS_PER_LONG) +#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) +#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) + +struct bitmap { + u64 bits[0]; +}; + +struct bitmap __arena *bmp_alloc(size_t bits); +void bmp_free(struct bitmap __arena *bmp); + +void bmp_set_bit(u32 bit, struct bitmap __arena *bmp); +void bmp_clear_bit(u32 bit, struct bitmap __arena *bmp); +bool bmp_test_bit(u32 bit, struct bitmap __arena *bmp); +bool bmp_test_and_clear_bit(u32 bit, struct bitmap __arena *bmp); + +void bmp_clear(size_t bits, struct bitmap __arena *bmp); +void bmp_and(size_t bits, struct bitmap __arena *dst, struct bitmap __arena *src1, struct bitmap __arena *src2); +void bmp_or(size_t bits, struct bitmap __arena *dst, struct bitmap __arena *src1, struct bitmap __arena *src2); +bool bmp_empty(size_t bits, struct bitmap __arena *bmp); +void bmp_copy(size_t bits, struct bitmap __arena *dst, struct bitmap __arena *src); + +bool bmp_intersects(size_t bits, struct bitmap __arena *arg1, struct bitmap __arena *arg2); +bool bmp_subset(size_t bits, struct bitmap __arena *big, struct bitmap __arena *small); +void bmp_print(size_t bits, struct bitmap __arena *bmp); diff --git a/tools/testing/selftests/bpf/libarena/src/bitmap.bpf.c b/tools/testing/selftests/bpf/libarena/src/bitmap.bpf.c new file mode 100644 index 000000000000..a8ca814aa0c8 --- /dev/null +++ b/tools/testing/selftests/bpf/libarena/src/bitmap.bpf.c @@ -0,0 +1,191 @@ +// SPDX-License-Identifier: LGPL-2.1 OR BSD-2-Clause +/* + * Copyright (c) 2025-2026 Meta Platforms, Inc. and affiliates. + * Copyright (c) 2025-2026 Emil Tsalapatis + */ + +#include + +#include +#include + +__weak +struct bitmap __arena *bmp_alloc(size_t bits) +{ + struct bitmap __arena *bmp; + size_t size = BITS_TO_LONGS(bits) * sizeof(bmp->bits[0]); + + /* Assume long-aligned masks. */ + if (bits % BITS_PER_LONG) + return NULL; + + bmp = (struct bitmap __arena *)arena_malloc(size); + if (!bmp) + return NULL; + + bmp_clear(bits, bmp); + + return bmp; +} + +__weak +void bmp_free(struct bitmap __arena *bmp) +{ + arena_free(bmp); +} + +__weak +void bmp_set_bit(u32 bit, struct bitmap __arena *bmp) +{ + bmp->bits[BIT_WORD(bit)] |= BIT_MASK(bit); +} + +__weak +void bmp_clear_bit(u32 bit, struct bitmap __arena *bmp) +{ + bmp->bits[BIT_WORD(bit)] &= ~BIT_MASK(bit); +} + +__weak +bool bmp_test_bit(u32 bit, struct bitmap __arena *bmp) +{ + return bmp->bits[BIT_WORD(bit)] & BIT_MASK(bit); +} + +__weak +bool bmp_test_and_clear_bit(u32 bit, struct bitmap __arena *bmp) +{ + u64 val = BIT_MASK(bit); + u32 idx = BIT_WORD(bit); + u64 actual; + + do { + u64 old = bmp->bits[idx]; + + if (!(old & val)) + return false; + + u64 new = old & ~val; + actual = cmpxchg(&bmp->bits[idx], old, new); + + if (actual == old) + return true; + + } while (can_loop); + + return false; +} + +__weak +void bmp_clear(size_t bits, struct bitmap __arena *bmp) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) + bmp->bits[i] = 0; +} + +static __always_inline u64 bmp_last_word_mask(size_t bits) +{ + u32 rem = bits % BITS_PER_LONG; + + return rem ? (1ULL << rem) - 1 : ~0ULL; +} + +__weak +void bmp_and(size_t bits, struct bitmap __arena *dst, struct bitmap __arena *src1, struct bitmap __arena *src2) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) + dst->bits[i] = src1->bits[i] & src2->bits[i]; + + if (nwords && bits % BITS_PER_LONG) + dst->bits[nwords - 1] &= bmp_last_word_mask(bits); +} + +__weak +void bmp_or(size_t bits, struct bitmap __arena *dst, struct bitmap __arena *src1, struct bitmap __arena *src2) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) + dst->bits[i] = src1->bits[i] | src2->bits[i]; + + if (nwords && bits % BITS_PER_LONG) + dst->bits[nwords - 1] &= bmp_last_word_mask(bits); +} + +__weak +bool bmp_empty(size_t bits, struct bitmap __arena *bmp) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) { + u64 mask = (i == nwords - 1) ? bmp_last_word_mask(bits) : ~0ULL; + + if (bmp->bits[i] & mask) + return false; + } + + return true; +} + +__weak +void bmp_copy(size_t bits, struct bitmap __arena *dst, struct bitmap __arena *src) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) + dst->bits[i] = src->bits[i]; + + if (nwords && bits % BITS_PER_LONG) + dst->bits[nwords - 1] &= bmp_last_word_mask(bits); +} + +__weak +bool bmp_subset(size_t bits, struct bitmap __arena *big, struct bitmap __arena *small) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) { + u64 mask = (i == nwords - 1) ? bmp_last_word_mask(bits) : ~0ULL; + + if (~big->bits[i] & small->bits[i] & mask) + return false; + } + + return true; +} + +__weak +bool bmp_intersects(size_t bits, struct bitmap __arena *arg1, struct bitmap __arena *arg2) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) { + u64 mask = (i == nwords - 1) ? bmp_last_word_mask(bits) : ~0ULL; + + if (arg1->bits[i] & arg2->bits[i] & mask) + return true; + } + + return false; +} + +__weak +void bmp_print(size_t bits, struct bitmap __arena *bmp) +{ + size_t nwords = BITS_TO_LONGS(bits); + volatile u32 i; + + for (i = zero; i < nwords && can_loop; i++) + arena_stderr("%016llx ", bmp->bits[i]); +} -- 2.54.0