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 23B0E461B0; Wed, 12 Feb 2025 05:50:09 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id E337E402A7; Wed, 12 Feb 2025 05:50:08 +0100 (CET) Received: from fhigh-b8-smtp.messagingengine.com (fhigh-b8-smtp.messagingengine.com [202.12.124.159]) by mails.dpdk.org (Postfix) with ESMTP id 35E3740269 for ; Wed, 12 Feb 2025 05:50:07 +0100 (CET) Received: from phl-compute-12.internal (phl-compute-12.phl.internal [10.202.2.52]) by mailfhigh.stl.internal (Postfix) with ESMTP id 4C75325401E9; Tue, 11 Feb 2025 23:50:06 -0500 (EST) Received: from phl-mailfrontend-01 ([10.202.2.162]) by phl-compute-12.internal (MEProxy); Tue, 11 Feb 2025 23:50:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= cc:cc:content-transfer-encoding:content-type:content-type:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to; s=fm3; t=1739335806; x=1739422206; bh=AZq3FWFxIAz7NcpnWmmObdWlZA/mVHXY2yfmGDFYdWM=; b= QK2Qmn68ElrBWCDw7rhfPgTE8nkFJvz6bcypaJHS2VwJ9Z4gSZU9aCkIsEhNqHCx qx5dbO0VShD8qwbfq9uDFHgRRN3K3pOrEkirdqS/aX1VzLr1BAHTltIu54PbdPFs Vub+qu1FlUYuuDvd2itqfnXc520pOsHiRF3vpPPdqavthjbzNOMK+/yhapORtMLv FJWtRISJr7LuBFDDANAef+9LU5W3886zPrqQdJVrXtPw0G6FwWHTYSXxIYNEA1bW BZSz70XoU6HAN2lrkVZgZUrdeQ5K4UwZRMLWnwxPP5rRPMjI7i9cf8zfssmuUDGV 9wy7SnmCte3hZlRbIUyeww== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:content-type:date:date:feedback-id:feedback-id :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm3; t=1739335806; x= 1739422206; bh=AZq3FWFxIAz7NcpnWmmObdWlZA/mVHXY2yfmGDFYdWM=; b=D Py17wnVuHZMBAR7eh+MLkFIWAqSjp6LrydRpmh1x7scD+t2B0K/XP/KHVcjZobZ2 tD3IKl5zPwPMgTKeTJdPovs0oVfcg+fSyHoI7b3CQJKSyAknhWx6wnUF0gfJeEdv qb+gFRlw4OlC+vp9jkaefi9oyKtlZZArcqAvIfDqQrZ+bnwM6q2m2MGWuQdUeZwZ EkyfiybAVdM1teJmW1DbizCsK+f6GZxDMo+TbC/k5K/GwfGgWXO4W28gxjzXk79F LYT5xUz9jE7SpBFxrBMIA5ycYOhoiEdlP1qyIVEKcblhH/+dOSVezhO3CxjYJH48 JMnTh7YIXqC1MoeBnrIrA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdegvdeliecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpggftfghnshhusghstghrihgsvgdp uffrtefokffrpgfnqfghnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivg hnthhsucdlqddutddtmdenucfjughrpefhvfevufffkfgjfhgggfgtsehtufertddttdej necuhfhrohhmpefvhhhomhgrshcuofhonhhjrghlohhnuceothhhohhmrghssehmohhnjh grlhhonhdrnhgvtheqnecuggftrfgrthhtvghrnhepjeduveehieevuddutdevfffgtdeg keeuveejffejgedtgeegkefgvdeugfefkeejnecuvehluhhsthgvrhfuihiivgeptdenuc frrghrrghmpehmrghilhhfrhhomhepthhhohhmrghssehmohhnjhgrlhhonhdrnhgvthdp nhgspghrtghpthhtohephedpmhhouggvpehsmhhtphhouhhtpdhrtghpthhtohepfigrth hhshgrlhgrrdhvihhthhgrnhgrghgvsegrrhhmrdgtohhmpdhrtghpthhtohepsghruhgt vgdrrhhitghhrghrughsohhnsehinhhtvghlrdgtohhmpdhrtghpthhtohepuggvvhesug hpughkrdhorhhgpdhrtghpthhtohepnhgusegrrhhmrdgtohhmpdhrtghpthhtohepughh rhhuvhdrthhrihhprghthhhisegrrhhmrdgtohhm X-ME-Proxy: Feedback-ID: i47234305:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Tue, 11 Feb 2025 23:50:04 -0500 (EST) From: Thomas Monjalon To: Wathsala Vithanage Cc: Bruce Richardson , dev@dpdk.org, nd@arm.com, Dhruv Tripathi Subject: Re: [PATCH v3 1/2] config/arm: strict use of -mcpu for supported CPUs Date: Wed, 12 Feb 2025 05:50:02 +0100 Message-ID: <62120729.matp6XCIr4@thomas> In-Reply-To: <20250106183146.540161-1-wathsala.vithanage@arm.com> References: <20241028233139.922029-1-wathsala.vithanage@arm.com> <20250106183146.540161-1-wathsala.vithanage@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" 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 06/01/2025 19:31, Wathsala Vithanage: > Arm recommends using -mcpu over -march and march-extensions when the > compiler supports the target CPU (neoverse-n1 etc.). Arm build so far > has been an amalgam of -mcpu and -march. When march is in use, it has > been the case so far to silently fall back to a downgraded march when > the compiler does not support the requested march. This is unnecessary > and confusing to an end user who could be building DPDK with a > particular ISA version and performance expectations in mind. > > This patch aims to rectify both the above issues. For part numbers that > has a corresponding -mcpu, this patch removes all references to march > and march_features from meson.build. For those SOCs that do not have a > corresponding -mcpu, a pseudo cpu name in the format mcpu_ is > introduced and referenced in the mcpu field in the part number > dictionary of the part_number_config dictionary. The definition of the > mcpu_ must be provided in the mcpu_defs dictionary. > Each mcpu_ dictionary in the mcpu_defs have a march field and > a march_extensions field to construct the optimal compiler setting for > an SOC that has no corresponding -mcpu value. This patch alters the > behavior of the build system such that it will no longer silently fall > back to an older ISA version, it will only perform what's specified in > the build dictionaries, if the compiler does not support the specified > configuration it will fail with an error message. > > How to add a new SOC to the build system with these changes? > If compiler supports mcpu follow the usual practice but without march > and march_features fields in the part number dictionary. If mcpu is not > available or buggy (misses certain features) for some reason follow the > same process but set mcpu field to a string in the form 'mcpu_foo' > (pseudo mcpu mentioned earlier). Then in the mcpu_defs dictionary add > mcpu_foo dictionary as shown. > > 'mcpu_foo': { > 'march': 'armv8.2-a', > 'march_extensions': [rcpc] > } > > march_extensions is a comma separated list of march extensions supported > by the compiler such as sve, crypto etc. Empty match_extensions allowed > as use of such extensions are optional. > > Signed-off-by: Wathsala Vithanage > Reviewed-by: Dhruv Tripathi Series applied with the hope there is no regression, thanks.