From patchwork Tue Oct 24 15:18:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King \(Oracle\)" X-Patchwork-Id: 737593 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 673FB31A89; Tue, 24 Oct 2023 15:18:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="jYvWVqlC" Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8BED26BB; Tue, 24 Oct 2023 08:18:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=IJ7uYec08eqfuMxFZrHnSEcaft5KZu54sS7ZNCcryYs=; b=jYvWVqlCApkWNPfR6cAqR56m9Q q/uDG0++Gf1LKwvUATqH2/HHLsrgwdtJ+BeV/LcQUy3mgxTKjZMMBCasy377IlLdVDXBTutup20Bx AOHX+6RfU48ufAu5zcB7c+JBDj4iJugXUbd/X6bNVHKqnCmmg57lACiIs8euHoCBoxARM4DmumVWq hFbEk8A35olBO2FvYluxan0xYW5q81eExG6xzwEsoS7UksiGwOQzBQwIkut0ZB1E+f3olnozZwwr1 W1q9gkoD44/mckOaqrqcVmwEeE8Q+bTfGfC7EfPQIexJLoqWTRu23M91wNstj743bbzWCtenM0PWp +v2LYvbg==; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:46130 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1qvJAj-0004Tf-20; Tue, 24 Oct 2023 16:18:21 +0100 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1qvJAl-00AqRM-2s; Tue, 24 Oct 2023 16:18:23 +0100 In-Reply-To: References: From: Russell King (Oracle) To: linux-pm@vger.kernel.org, loongarch@lists.linux.dev, linux-acpi@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, kvmarm@lists.linux.dev, x86@kernel.org, linux-csky@vger.kernel.org, linux-doc@vger.kernel.org, linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org Cc: Salil Mehta , Jean-Philippe Brucker , jianyong.wu@arm.com, justin.he@arm.com, James Morse , "Rafael J. Wysocki" , Len Brown , Robert Moore , acpica-devel@lists.linuxfoundation.org Subject: [PATCH 26/39] ACPI: Add post_eject to struct acpi_scan_handler for cpu hotplug Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline Message-Id: Sender: Russell King Date: Tue, 24 Oct 2023 16:18:23 +0100 From: James Morse struct acpi_scan_handler has a detach callback that is used to remove a driver when a bus is changed. When interacting with an eject-request, the detach callback is called before _EJ0. This means the ACPI processor driver can't use _STA to determine if a CPU has been made not-present, or some of the other _STA bits have been changed. acpi_processor_remove() needs to know the value of _STA after _EJ0 has been called. Add a post_eject callback to struct acpi_scan_handler. This is called after acpi_scan_hot_remove() has successfully called _EJ0. Because acpi_bus_trim_one() also clears the handler pointer, it needs to be told if the caller will go on to call acpi_bus_post_eject(), so that acpi_device_clear_enumerated() and clearing the handler pointer can be deferred. The existing not-used pointer is used for this. Signed-off-by: James Morse Reviewed-by: Joanthan Cameron --- drivers/acpi/acpi_processor.c | 4 +-- drivers/acpi/scan.c | 52 ++++++++++++++++++++++++++++++----- include/acpi/acpi_bus.h | 1 + 3 files changed, 48 insertions(+), 9 deletions(-) diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index 26e3efb74614..b6f5005985c3 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -459,7 +459,7 @@ static int acpi_processor_add(struct acpi_device *device, #ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU /* Removal */ -static void acpi_processor_remove(struct acpi_device *device) +static void acpi_processor_post_eject(struct acpi_device *device) { struct acpi_processor *pr; @@ -627,7 +627,7 @@ static struct acpi_scan_handler processor_handler = { .ids = processor_device_ids, .attach = acpi_processor_add, #ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU - .detach = acpi_processor_remove, + .post_eject = acpi_processor_post_eject, #endif .hotplug = { .enabled = true, diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 4343888c76d5..adfd24f4d00c 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -244,18 +244,28 @@ static int acpi_scan_try_to_offline(struct acpi_device *device) return 0; } -static int acpi_bus_trim_one(struct acpi_device *adev, void *not_used) +/** + * acpi_bus_trim_one() - Detach scan handlers and drivers from ACPI device + * objects. + * @adev: Root of the ACPI namespace scope to walk. + * @eject: Pointer to a bool that indicates if this was due to an + * eject-request. + * + * Must be called under acpi_scan_lock. + * If @eject points to true, clearing the device enumeration is deferred until + * acpi_bus_post_eject() is called. + */ +static int acpi_bus_trim_one(struct acpi_device *adev, void *eject) { struct acpi_scan_handler *handler = adev->handler; + bool is_eject = *(bool *)eject; - acpi_dev_for_each_child_reverse(adev, acpi_bus_trim_one, NULL); + acpi_dev_for_each_child_reverse(adev, acpi_bus_trim_one, eject); adev->flags.match_driver = false; if (handler) { if (handler->detach) handler->detach(adev); - - adev->handler = NULL; } else { device_release_driver(&adev->dev); } @@ -265,7 +275,12 @@ static int acpi_bus_trim_one(struct acpi_device *adev, void *not_used) */ acpi_device_set_power(adev, ACPI_STATE_D3_COLD); adev->flags.initialized = false; - acpi_device_clear_enumerated(adev); + + /* For eject this is deferred to acpi_bus_post_eject() */ + if (!is_eject) { + adev->handler = NULL; + acpi_device_clear_enumerated(adev); + } return 0; } @@ -278,15 +293,36 @@ static int acpi_bus_trim_one(struct acpi_device *adev, void *not_used) */ void acpi_bus_trim(struct acpi_device *adev) { - acpi_bus_trim_one(adev, NULL); + bool eject = false; + + acpi_bus_trim_one(adev, &eject); } EXPORT_SYMBOL_GPL(acpi_bus_trim); +static int acpi_bus_post_eject(struct acpi_device *adev, void *not_used) +{ + struct acpi_scan_handler *handler = adev->handler; + + acpi_dev_for_each_child_reverse(adev, acpi_bus_post_eject, NULL); + + if (handler) { + if (handler->post_eject) + handler->post_eject(adev); + + adev->handler = NULL; + } + + acpi_device_clear_enumerated(adev); + + return 0; +} + static int acpi_scan_hot_remove(struct acpi_device *device) { acpi_handle handle = device->handle; unsigned long long sta; acpi_status status; + bool eject = true; if (device->handler && device->handler->hotplug.demand_offline) { if (!acpi_scan_is_offline(device, true)) @@ -299,7 +335,7 @@ static int acpi_scan_hot_remove(struct acpi_device *device) acpi_handle_debug(handle, "Ejecting\n"); - acpi_bus_trim(device); + acpi_bus_trim_one(device, &eject); acpi_evaluate_lck(handle, 0); /* @@ -322,6 +358,8 @@ static int acpi_scan_hot_remove(struct acpi_device *device) } else if (sta & ACPI_STA_DEVICE_ENABLED) { acpi_handle_warn(handle, "Eject incomplete - status 0x%llx\n", sta); + } else { + acpi_bus_post_eject(device, NULL); } return 0; diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 254685085c82..1b7e1acf925b 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -127,6 +127,7 @@ struct acpi_scan_handler { bool (*match)(const char *idstr, const struct acpi_device_id **matchid); int (*attach)(struct acpi_device *dev, const struct acpi_device_id *id); void (*detach)(struct acpi_device *dev); + void (*post_eject)(struct acpi_device *dev); void (*bind)(struct device *phys_dev); void (*unbind)(struct device *phys_dev); struct acpi_hotplug_profile hotplug;