From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 70E3C46565; Fri, 11 Apr 2025 21:39:48 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id EA8F84026A; Fri, 11 Apr 2025 21:39:47 +0200 (CEST) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by mails.dpdk.org (Postfix) with ESMTP id 048B14025F for ; Fri, 11 Apr 2025 21:39:45 +0200 (CEST) Received: by linux.microsoft.com (Postfix, from userid 1213) id 272922114DBB; Fri, 11 Apr 2025 12:39:45 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 272922114DBB DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1744400385; bh=B9fzec7y7MI19t+u/qTGyy0BREUup+37BPS+QttFVig=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C1d5kzbyf54udyqKm3dFg095DodoKmwfcPZBLhS3eCXuQ5KS6A49avK1obLuvFGaG Yx/j9pRfkwR+KsHvAnpJjnVNSMTIzcdDpy5jJQoQTHqSSCtwUb04csC5IaillCRxSv 1zs4rwZ8uIjasB9GlJRsDU0bOt615tnl83hAu+h0= From: Andre Muezerie To: Tyler Retzlaff Cc: dev@dpdk.org, Andre Muezerie Subject: [PATCH 1/4] eal: add macro to embed information in binaries Date: Fri, 11 Apr 2025 12:39:30 -0700 Message-Id: <1744400374-26620-2-git-send-email-andremue@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1744400374-26620-1-git-send-email-andremue@linux.microsoft.com> References: <1744400374-26620-1-git-send-email-andremue@linux.microsoft.com> X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org DPDK uses GCC attribute "used" through macro __rte_used to indicate that a variable not referenced in the code should be assumed being used and therefore not be optimized away. This technique is used to embed information in the binaries, by having crafted information stored in them. MSVC offers similar functionality, but it differs significantly: MSVC requires a pragma to be used to send a command to the linker telling it explicitly the name of the symbol that should be included (even if not referenced). As a side-effect, variables called out to be included cannot be static, otherwise their symbols are not "seen" by the linker. This restriction requires some DPDK code to be refactored. To assimilate these requirements/restrictions, macro RTE_INCLUDE is introduced in this patch. Signed-off-by: Andre Muezerie --- lib/eal/common/eal_common_options.c | 2 +- lib/eal/include/rte_common.h | 6 ++++++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/lib/eal/common/eal_common_options.c b/lib/eal/common/eal_common_options.c index b6fff7ec05..8d115a5bd7 100644 --- a/lib/eal/common/eal_common_options.c +++ b/lib/eal/common/eal_common_options.c @@ -135,7 +135,7 @@ static const char *default_solib_dir = RTE_EAL_PMD_PATH; * Note: PLEASE DO NOT ALTER THIS without making a corresponding * change to usertools/dpdk-pmdinfo.py */ -static const char dpdk_solib_path[] __rte_used = +RTE_INCLUDE(const char, dpdk_solib_path)[] = "DPDK_PLUGIN_PATH=" RTE_EAL_PMD_PATH; TAILQ_HEAD(device_option_list, device_option); diff --git a/lib/eal/include/rte_common.h b/lib/eal/include/rte_common.h index a6085dce27..4c5a3b668f 100644 --- a/lib/eal/include/rte_common.h +++ b/lib/eal/include/rte_common.h @@ -231,6 +231,12 @@ typedef uint16_t unaligned_uint16_t; /** * Force symbol to be generated even if it appears to be unused. */ +#ifdef RTE_TOOLCHAIN_MSVC +#define RTE_INCLUDE(type, name) __pragma(comment(linker, "/include:" RTE_STR(name))) type name +#else +#define RTE_INCLUDE(type, name) __attribute__((used)) type name +#endif + #ifdef RTE_TOOLCHAIN_MSVC #define __rte_used #else -- 2.49.0.vfs.0.0