From nobody Mon Jan 08 17:55:55 2024 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4T81vR4Pxqz56G8s; Mon, 8 Jan 2024 17:56:03 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4T81vR1LhVz40Bh; Mon, 8 Jan 2024 17:56:02 +0000 (UTC) (envelope-from kostikbel@gmail.com) Authentication-Results: mx1.freebsd.org; none Received: from tom.home (kib@localhost [127.0.0.1] (may be forged)) by kib.kiev.ua (8.17.1/8.17.1) with ESMTP id 408HttFi016375; Mon, 8 Jan 2024 19:55:58 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 408HttFi016375 Received: (from kostik@localhost) by tom.home (8.17.1/8.17.1/Submit) id 408Httu1016374; Mon, 8 Jan 2024 19:55:55 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Mon, 8 Jan 2024 19:55:55 +0200 From: Konstantin Belousov To: Himanshu Chauhan Cc: freebsd-riscv@freebsd.org, freebsd-hackers@freebsd.org Subject: Re: Calling a function on other CPUs in an SMP machine Message-ID: References: <7A8DC6C8-9582-455C-B05D-9F24838A9070@thechauhan.dev> List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <7A8DC6C8-9582-455C-B05D-9F24838A9070@thechauhan.dev> X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=4.0.0 X-Spam-Checker-Version: SpamAssassin 4.0.0 (2022-12-14) on tom.home X-Rspamd-Queue-Id: 4T81vR1LhVz40Bh X-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US] On Mon, Jan 08, 2024 at 08:09:18PM +0530, Himanshu Chauhan wrote: > Hi all, > > What is the best way to call a function (like a per-cpu setup function from a driver) on remote CPUs in an SMP machine? > I looked at the different IPIs defined but there isn’t one that does this. Could anyone please point me where else to look? Look at smp_rendezvous() and might be smp_rendezvous_cpus(). It is a powerful convenience wrapper around IPI.