From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1805C367F31 for ; Wed, 24 Jun 2026 15:36:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782315408; cv=none; b=GcUodAbNxOmGMpGiQRj+lWHs8+lM4QdXi1iBt+z5ranWj2z3KIAtTB5utUxbRJSUPPHUeVQaHAOmKBWN1fQ/ef+FwF6Lcx0ccZ9Ysuo2S2QFUo/TV4hqeAjxdN/KdoOJZReoqcXbokPIFsSwpxldMh/sXLRYSF1GOUGPotjTYYs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782315408; c=relaxed/simple; bh=M50mZOnjSmcU5WbMjUBbVWCmMvSNyLoYovIMUHigCII=; h=Message-ID:Date:MIME-Version:Subject:To:References:From:Cc: In-Reply-To:Content-Type; b=bJdJIQ6fXPRzrDu5jOyhq0mGhXo2yWikj0PWtNZ60NCaVq0fhOGZAZTqgjH+p5DPc0EvChRwVJb5pkxOfei1tRKddiXzrhweOOUsMhI+zylqKZvQncEgNmRkCipMp/uZaij01ZpFsfQ7IxKQu7U6pXFLvEsAhJ7Z/B/egN1LxtA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=eDF/UWkJ; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="eDF/UWkJ" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 045C125E1; Wed, 24 Jun 2026 08:36:41 -0700 (PDT) Received: from [10.2.213.11] (e137867.arm.com [10.2.213.11]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ADA8A3F905; Wed, 24 Jun 2026 08:36:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782315405; bh=M50mZOnjSmcU5WbMjUBbVWCmMvSNyLoYovIMUHigCII=; h=Date:Subject:To:References:From:Cc:In-Reply-To:From; b=eDF/UWkJ1ftcZgGHDRFVOkZp7p939OiySPPJMXRgirVHoD/S3mZhG5XqG4z+vA11q ZOzjODhiJywBROb4DUhD9hgJB2V5R0PKL5dWWgxByxMP76ladlXW0l4kOnPCfcoDCr jXQyh12curLtGk8fOjT+S25mvfTvXEyWWA88wfL0= Message-ID: <0b708c88-ff7c-40ff-8de8-800ab61677f0@arm.com> Date: Wed, 24 Jun 2026 16:36:39 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v15 11/11] arm64: Inline el0_svc_common() To: Jinjie Ruan References: <20260511092103.1974980-1-ruanjinjie@huawei.com> <20260511092103.1974980-12-ruanjinjie@huawei.com> From: Ada Couprie Diaz Cc: Ada Couprie Diaz , catalin.marinas@arm.com, will@kernel.org, oleg@redhat.com, tglx@kernel.org, peterz@infradead.org, luto@kernel.org, kees@kernel.org, wad@chromium.org, mark.rutland@arm.com, yeoreum.yun@arm.com, linusw@kernel.org, kevin.brodsky@arm.com, ldv@strace.io, thuth@redhat.com, james.morse@arm.com, song@kernel.org, anshuman.khandual@arm.com, broonie@kernel.org, ryan.roberts@arm.com, pengcan@kylinos.cn, liqiang01@kylinos.cn, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Content-Language: en-US, en-GB, fr Organization: Arm Ltd. In-Reply-To: <20260511092103.1974980-12-ruanjinjie@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 11/05/2026 10:21, Jinjie Ruan wrote: > After converting arm64 to Generic Entry framework, the compiler no longer > inlines el0_svc_common() into its caller do_el0_svc(). This introduces > a small but measurable overhead in the critical system call path. > > Manually forcing el0_svc_common() to be inlined restores the > performance. Benchmarking with perf bench syscall basic on a > Kunpeng 920 platform (based on v6.19-rc1) shows a ~1% performance > uplift. > > Inlining this function reduces function prologue/epilogue overhead > and allows for better compiler optimization in the hot system call > dispatch path. > > | Metric | W/O this patch | With this patch | Change | > | ---------- | -------------- | --------------- | --------- | > | Total time | 2.195 [sec] | 2.171 [sec] | ↓1.1% | > | usecs/op | 0.219575 | 0.217192 | ↓1.1% | > | ops/sec | 4,554,260 | 4,604,225 | ↑1.1% | > > Cc: Mark Rutland > Cc: Will Deacon > Cc: Catalin Marinas > Reviewed-by: Linus Walleij > Reviewed-by: Yeoreum Yun > Reviewed-by: Kevin Brodsky > Signed-off-by: Jinjie Ruan > --- Reviewed-by: Ada Couprie Diaz