From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754839Ab3DKUx0 (ORCPT ); Thu, 11 Apr 2013 16:53:26 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:17239 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935873Ab3DKUtb (ORCPT ); Thu, 11 Apr 2013 16:49:31 -0400 X-Authority-Analysis: v=2.0 cv=F+XVh9dN c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=Ciwy3NGCPMMA:10 a=_qIFQ5jD3aUA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=mTwAkanW7F0A:10 a=QyXUC8HyAAAA:8 a=klgB0MMPG5ptXD9YpV0A:9 a=dGJ0OcVc7YAA:10 a=jeBq3FmKZ4MA:10 a=gVYdi1RkTh040z5e:21 a=TyMX6_5--YLiefQ6:21 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-Id: <20130411202557.512819785@goodmis.org> User-Agent: quilt/0.60-1 Date: Thu, 11 Apr 2013 16:26:12 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Rafael J. Wysocki" Subject: [ 069/171 ] ACPI: Rework acpi_get_child() to be more efficient References: <20130411202503.783159048@goodmis.org> Content-Disposition: inline; filename=0069-ACPI-Rework-acpi_get_child-to-be-more-efficient.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.6.11.2 stable review patch. If anyone has any objections, please let me know. ------------------ From: "Rafael J. Wysocki" [ Upstream commit 33f767d767e9a684e9cd60704d4c049a2014c8d5 ] Observe that acpi_get_child() doesn't need to use the helper struct acpi_find_child structure and change it to work without it. Also, using acpi_get_object_info() to get the output of _ADR for the given device is overkill, because that function does much more than just evaluating _ADR (let alone the additional memory allocation done by it). Moreover, acpi_get_child() doesn't need to loop any more once it has found a matching handle, so make it stop in that case. To prevent the results from changing, make it use do_acpi_find_child() as a post-order callback. Signed-off-by: Rafael J. Wysocki Signed-off-by: Steven Rostedt --- drivers/acpi/glue.c | 35 +++++++++++++---------------------- 1 file changed, 13 insertions(+), 22 deletions(-) diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 243ee85..6eff12f 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -88,40 +88,31 @@ static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle) return ret; } -/* Get device's handler per its address under its parent */ -struct acpi_find_child { - acpi_handle handle; - u64 address; -}; - -static acpi_status -do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv) +static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl_not_used, + void *addr_p, void **ret_p) { + unsigned long long addr; acpi_status status; - struct acpi_device_info *info; - struct acpi_find_child *find = context; - - status = acpi_get_object_info(handle, &info); - if (ACPI_SUCCESS(status)) { - if ((info->address == find->address) - && (info->valid & ACPI_VALID_ADR)) - find->handle = handle; - kfree(info); + + status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); + if (ACPI_SUCCESS(status) && addr == *((u64 *)addr_p)) { + *ret_p = handle; + return AE_CTRL_TERMINATE; } return AE_OK; } acpi_handle acpi_get_child(acpi_handle parent, u64 address) { - struct acpi_find_child find = { NULL, address }; + void *ret = NULL; if (!parent) return NULL; - acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, - 1, do_acpi_find_child, NULL, &find, NULL); - return find.handle; -} + acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, NULL, + do_acpi_find_child, &address, &ret); + return (acpi_handle)ret; +} EXPORT_SYMBOL(acpi_get_child); /* Link ACPI devices with physical devices */ -- 1.7.10.4