From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85E61C77B7A for ; Thu, 1 Jun 2023 22:40:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230492AbjFAWk1 (ORCPT ); Thu, 1 Jun 2023 18:40:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50418 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231558AbjFAWk0 (ORCPT ); Thu, 1 Jun 2023 18:40:26 -0400 Received: from mail-lj1-x234.google.com (mail-lj1-x234.google.com [IPv6:2a00:1450:4864:20::234]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8504712C for ; Thu, 1 Jun 2023 15:40:24 -0700 (PDT) Received: by mail-lj1-x234.google.com with SMTP id 38308e7fff4ca-2b1a6a8e851so12853341fa.2 for ; Thu, 01 Jun 2023 15:40:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1685659222; x=1688251222; 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=FBkV9oYQPFu7USkDL/ITikjBCLxq5r+G6YZDTAlhVT8=; b=Bg4Gnw+kQbHtCTcaxAuNG/+ek6ULfWBV/ClnH3srOBd8BpEewrwJpuGC5I9m8zEXl8 R725RSkr9ip+pZ6ja/LYABZECdqOML8CGJhd7LeMo88O/TEcl1kqLjAcBIgWfbdFA38X 1FlsvzV4iiRWXTx7sQDQrMnfTCtNFMzilS9lKRk9ut+sRogRwA1GzF+w8Hm7zzkYCgft COSJswxh4Xxtss2eS776AGvDSzA2zMqEfC6FqCZRMJLnzTmofFAXu69ZPJFRu6e+5C/m QU0DGLpa/Gyxq6HNk97Kr9eg5bvjXi9H8wllT75RACgbTsJHXP7esCTlmGiyslvwp4Vi fRSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685659222; x=1688251222; 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=FBkV9oYQPFu7USkDL/ITikjBCLxq5r+G6YZDTAlhVT8=; b=EqP/Cax+1QiOXvHqVBI3uX1dZSu85bgFmDOKJTu0ESnrNeHSGxgMfpEaxbizUr1PPK D5CfLtCtoyZNWiHmLNmEgjYDY8mTiO2UkJGlv35kGrz3yY+JEIA4r2NwQUJ2/zjUU+4y L2nLPhlYZaRpYKcu3IEOFMh1rnQrTCorZKV/fjJ883pYSjmxsVBFXfuQWBfqd8/Izkz8 yp2xq/bVbtOSOsJ+2CYX5MzVqjwvOG/NP7FAGMN79XsqfafFYd2GLSYRMEvgTAgUFgiZ sUACLAch0tZ3VudkSPY6EVHRMtaeYtuw+2Ml2PJjalRJB0ibuGVGa4ID8iDDwlhGHJ78 8KEg== X-Gm-Message-State: AC+VfDwfNccsvK3NObQjX4qyemqAs8dd+AmJnuxNd+6Xe7cbOKF/pBzy RIi1zglw2NGcEwS19j8YQ54cJWhtpns= X-Google-Smtp-Source: ACHHUZ42clg0PX/wg5XsVCyhnnRJdeEPVVfMu912kcjAE4zF9wqcmXEeO51Xosh3iN2aGe76tLPYQw== X-Received: by 2002:a2e:9c8b:0:b0:2ad:90c8:7fa3 with SMTP id x11-20020a2e9c8b000000b002ad90c87fa3mr540251lji.29.1685659221698; Thu, 01 Jun 2023 15:40:21 -0700 (PDT) Received: from ldmartin-desk2.jf.intel.com ([134.134.137.83]) by smtp.gmail.com with ESMTPSA id se24-20020a170906ce5800b009662b4230cesm11253318ejb.148.2023.06.01.15.40.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 01 Jun 2023 15:40:20 -0700 (PDT) From: Lucas De Marchi To: linux-modules@vger.kernel.org Cc: Luis Chamberlain , Lucas De Marchi Subject: [PATCH 5/5] libkmod: Use kernel decompression when available Date: Thu, 1 Jun 2023 15:40:01 -0700 Message-Id: <20230601224001.23397-6-lucas.de.marchi@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230601224001.23397-1-lucas.de.marchi@gmail.com> References: <20230601224001.23397-1-lucas.de.marchi@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: With the recent changes to bypass loading the file it's possible to reduce the work in userspace and delegating it to the kernel. Without any compression to illustrate: Before: read(3, "\177ELF\2\1", 6) = 6 lseek(3, 0, SEEK_SET) = 0 newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=238592, ...}, AT_EMPTY_PATH) = 0 mmap(NULL, 238592, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fd85cbd1000 finit_module(3, "", 0) = 0 munmap(0x7fd85cbd1000, 238592) = 0 close(3) = 0 After: read(3, "\177ELF\2\1", 6) = 6 lseek(3, 0, SEEK_SET) = 0 finit_module(3, "", 0) = 0 close(3) = 0 When using kernel compression now it's also possible to direct libkmod to take the finit_module() path, avoiding the decompression in userspace and just delegating it to the kernel. Before: read(3, "(\265/\375\244\0", 6) = 6 lseek(3, 0, SEEK_SET) = 0 read(3, "(\265/\375\244", 5) = 5 mmap(NULL, 135168, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f3fa431e000 read(3, "\0\244\3\0\\y\6", 7) = 7 mmap(NULL, 372736, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f3fa414f000 brk(0x55944c6a1000) = 0x55944c6a1000 read(3, "\356|\6G\27U\20 \312\260s\211\335\333\263\326\330\336\273O\211\356\306K\360Z\341\374U6\342\221"..., 53038) = 53038 mremap(0x7f3fa431e000, 135168, 266240, MREMAP_MAYMOVE) = 0x7f3fa410e000 read(3, ",;\3\nqf\311\362\325\211\7\341\375A\355\221\371L\\\5\7\375 \32\246<(\258=K\304"..., 20851) = 20851 mremap(0x7f3fa410e000, 266240, 397312, MREMAP_MAYMOVE) = 0x7f3fa40ad000 read(3, ")\36\250\213", 4) = 4 read(3, "", 4) = 0 munmap(0x7f3fa414f000, 372736) = 0 init_module(0x7f3fa40ad010, 238592, "") = 0 munmap(0x7f3fa40ad000, 397312) = 0 close(3) = 0 After: read(3, "(\265/\375\244P", 6) = 6 lseek(3, 0, SEEK_SET) = 0 finit_module(3, "", 0x4 /* MODULE_INIT_??? */) = 0 close(3) = 0 Signed-off-by: Lucas De Marchi --- libkmod/libkmod-file.c | 4 ++-- libkmod/libkmod-internal.h | 3 ++- libkmod/libkmod-module.c | 17 +++++++++++++---- libkmod/libkmod.c | 5 +++++ 4 files changed, 22 insertions(+), 7 deletions(-) diff --git a/libkmod/libkmod-file.c b/libkmod/libkmod-file.c index 705770a..ffdda92 100644 --- a/libkmod/libkmod-file.c +++ b/libkmod/libkmod-file.c @@ -513,9 +513,9 @@ off_t kmod_file_get_size(const struct kmod_file *file) return file->size; } -bool kmod_file_get_direct(const struct kmod_file *file) +enum kmod_file_compression_type kmod_file_get_compression(const struct kmod_file *file) { - return file->compression == KMOD_FILE_COMPRESSION_NONE; + return file->compression; } int kmod_file_get_fd(const struct kmod_file *file) diff --git a/libkmod/libkmod-internal.h b/libkmod/libkmod-internal.h index 7b8a158..edb4eac 100644 --- a/libkmod/libkmod-internal.h +++ b/libkmod/libkmod-internal.h @@ -112,6 +112,7 @@ void kmod_pool_add_module(struct kmod_ctx *ctx, struct kmod_module *mod, const c void kmod_pool_del_module(struct kmod_ctx *ctx, struct kmod_module *mod, const char *key) __attribute__((nonnull(1, 2, 3))); const struct kmod_config *kmod_get_config(const struct kmod_ctx *ctx) __attribute__((nonnull(1))); +enum kmod_file_compression_type kmod_get_kernel_compression(const struct kmod_ctx *ctx) __attribute__((nonnull(1))); /* libkmod-config.c */ struct kmod_config_path { @@ -162,7 +163,7 @@ struct kmod_elf *kmod_file_get_elf(struct kmod_file *file) __attribute__((nonnul int kmod_file_load_contents(struct kmod_file *file) _must_check_ __attribute__((nonnull(1))); void *kmod_file_get_contents(const struct kmod_file *file) _must_check_ __attribute__((nonnull(1))); off_t kmod_file_get_size(const struct kmod_file *file) _must_check_ __attribute__((nonnull(1))); -bool kmod_file_get_direct(const struct kmod_file *file) _must_check_ __attribute__((nonnull(1))); +enum kmod_file_compression_type kmod_file_get_compression(const struct kmod_file *file) _must_check_ __attribute__((nonnull(1))); int kmod_file_get_fd(const struct kmod_file *file) _must_check_ __attribute__((nonnull(1))); void kmod_file_unref(struct kmod_file *file) __attribute__((nonnull(1))); diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c index 6ed5ad4..a9e1be8 100644 --- a/libkmod/libkmod-module.c +++ b/libkmod/libkmod-module.c @@ -864,15 +864,24 @@ extern long init_module(const void *mem, unsigned long len, const char *args); static int do_finit_module(struct kmod_module *mod, unsigned int flags, const char *args) { + enum kmod_file_compression_type compression, kernel_compression; unsigned int kernel_flags = 0; int err; /* - * Re-use ENOSYS, returned when there is no such syscall, so the - * fallback to init_module applies + * When module is not compressed or its compression type matches the + * one in use by the kernel, there is no need to read the file + * in userspace. Otherwise, re-use ENOSYS to trigger the same fallback + * as when finit_module() is not supported. */ - if (!kmod_file_get_direct(mod->file)) - return -ENOSYS; + compression = kmod_file_get_compression(mod->file); + kernel_compression = kmod_get_kernel_compression(mod->ctx); + if (!(compression == KMOD_FILE_COMPRESSION_NONE || + compression == kernel_compression)) + return ENOSYS; + + if (compression != KMOD_FILE_COMPRESSION_NONE) + kernel_flags |= MODULE_INIT_COMPRESSED_FILE; if (flags & KMOD_INSERT_FORCE_VERMAGIC) kernel_flags |= MODULE_INIT_IGNORE_VERMAGIC; diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c index 103469e..1b8773c 100644 --- a/libkmod/libkmod.c +++ b/libkmod/libkmod.c @@ -1016,3 +1016,8 @@ const struct kmod_config *kmod_get_config(const struct kmod_ctx *ctx) { return ctx->config; } + +enum kmod_file_compression_type kmod_get_kernel_compression(const struct kmod_ctx *ctx) +{ + return ctx->kernel_compression; +} -- 2.40.1