From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933083Ab2GBVQZ (ORCPT ); Mon, 2 Jul 2012 17:16:25 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:41248 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756196Ab2GBVQX (ORCPT ); Mon, 2 Jul 2012 17:16:23 -0400 From: Seth Jennings To: Greg Kroah-Hartman Cc: Seth Jennings , Andrew Morton , Dan Magenheimer , Konrad Rzeszutek Wilk , Nitin Gupta , Minchan Kim , Robert Jennings , linux-mm@kvack.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/4] zsmalloc: add single-page object fastpath in unmap Date: Mon, 2 Jul 2012 16:15:50 -0500 Message-Id: <1341263752-10210-3-git-send-email-sjenning@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1341263752-10210-1-git-send-email-sjenning@linux.vnet.ibm.com> References: <1341263752-10210-1-git-send-email-sjenning@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12070221-4242-0000-0000-00000230FB03 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Improve zs_unmap_object() performance by adding a fast path for objects that don't span pages. Signed-off-by: Seth Jennings --- drivers/staging/zsmalloc/zsmalloc-main.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c index a7a6f22..4942d41 100644 --- a/drivers/staging/zsmalloc/zsmalloc-main.c +++ b/drivers/staging/zsmalloc/zsmalloc-main.c @@ -774,6 +774,7 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle) } zs_copy_map_object(area->vm_buf, page, off, class->size); + area->vm_addr = NULL; return area->vm_buf; } EXPORT_SYMBOL_GPL(zs_map_object); @@ -788,6 +789,14 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle) struct size_class *class; struct mapping_area *area; + area = &__get_cpu_var(zs_map_area); + if (area->vm_addr) { + /* single-page object fastpath */ + kunmap_atomic(area->vm_addr); + put_cpu_var(zs_map_area); + return; + } + BUG_ON(!handle); obj_handle_to_location(handle, &page, &obj_idx); @@ -795,11 +804,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle) class = &pool->size_class[class_idx]; off = obj_idx_to_offset(page, obj_idx, class->size); - area = &__get_cpu_var(zs_map_area); - if (off + class->size <= PAGE_SIZE) - kunmap_atomic(area->vm_addr); - else - zs_copy_unmap_object(area->vm_buf, page, off, class->size); + zs_copy_unmap_object(area->vm_buf, page, off, class->size); put_cpu_var(zs_map_area); } EXPORT_SYMBOL_GPL(zs_unmap_object); -- 1.7.9.5