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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CE3B8C83F20 for ; Sun, 13 Jul 2025 17:26:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7hkA9J0yJ6LYuwj61ZyOGv+Xl/BzsgcrZZJOuPyYgKM=; b=ejKzqL0v90WkmsyeUpuPaHywXx BB/EwYfguo3nan0FXZe8CAkmnXr9+5eb56tAED9uWCINhi014vzyEONrmp6FaCW+Y1qbigk4g/rGt VBbI8rz9Hn3WHCNjYpcIdTzyTia/tst0S4y6fxwtAQ8lqAWUvWBnvRWkL5rUjQleSfDg9SPVNnwlL NMDnkh6QdmWX3kIpvb6V828UuoQ4O1YitHm5MI18y58jOvnfGnGGwJDy+wMCQy5dgkHoXn4NCfzUz BlQU4BKYJ6WhKtc8NGj4/Tfnn3qwpOZhsMFRMSKfIpTL8Uc2wxQB3biaz3oDF7jrQ3sFN1ivZkPZH FA4O+Gjw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ub0So-00000000RLm-01LJ; Sun, 13 Jul 2025 17:26:10 +0000 Received: from out-174.mta1.migadu.com ([2001:41d0:203:375::ae]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ub0Sk-00000000RKz-185E for linux-um@lists.infradead.org; Sun, 13 Jul 2025 17:26:08 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1752427563; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7hkA9J0yJ6LYuwj61ZyOGv+Xl/BzsgcrZZJOuPyYgKM=; b=WlS6Y2KYGcwzm99kCwEmxlwIZx5EnvAOpjDQQbo0PshypRNdCX4PdjnS2Yf5pXjh7xWsjj CNzUZvDtKHp2B1Lpoq6h+js0kqwSDcbWzDIDiU12gL83MuQyQ2MjJ+QKFumMHcaNTHbo8I hSolDv4GF3nqA3Ic9Ydwu+SMniDeI68= From: Tiwei Bie To: richard@nod.at, anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net Cc: linux-um@lists.infradead.org, tiwei.btw@antgroup.com, tiwei.bie@linux.dev Subject: [RFC PATCH 3/4] um: vdso: Implement __vdso_getcpu() via syscall Date: Mon, 14 Jul 2025 01:25:35 +0800 Message-Id: <20250713172536.404809-4-tiwei.bie@linux.dev> In-Reply-To: <20250713172536.404809-1-tiwei.bie@linux.dev> References: <20250713172536.404809-1-tiwei.bie@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250713_102606_756830_D7E9D263 X-CRM114-Status: UNSURE ( 8.75 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org From: Tiwei Bie We are going to support SMP in UML, so we can not hard code the CPU and NUMA node in __vdso_getcpu() anymore. Signed-off-by: Tiwei Bie --- arch/x86/um/vdso/um_vdso.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/arch/x86/um/vdso/um_vdso.c b/arch/x86/um/vdso/um_vdso.c index cbae2584124f..ee40ac446c1c 100644 --- a/arch/x86/um/vdso/um_vdso.c +++ b/arch/x86/um/vdso/um_vdso.c @@ -17,7 +17,7 @@ int __vdso_clock_gettime(clockid_t clock, struct __kernel_old_timespec *ts); int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz); __kernel_old_time_t __vdso_time(__kernel_old_time_t *t); -long __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused); +long __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *tcache); int __vdso_clock_gettime(clockid_t clock, struct __kernel_old_timespec *ts) { @@ -60,18 +60,16 @@ __kernel_old_time_t __vdso_time(__kernel_old_time_t *t) __kernel_old_time_t time(__kernel_old_time_t *t) __attribute__((weak, alias("__vdso_time"))); long -__vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused) +__vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *tcache) { - /* - * UML does not support SMP, we can cheat here. :) - */ + long ret; - if (cpu) - *cpu = 0; - if (node) - *node = 0; + asm volatile("syscall" + : "=a" (ret) + : "0" (__NR_getcpu), "D" (cpu), "S" (node), "d" (tcache) + : "rcx", "r11", "memory"); - return 0; + return ret; } long getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *tcache) -- 2.34.1