From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Lameter Subject: [thisops uV3 18/18] Fakekey: Simplify speakup_fake_key_pressed through this_cpu_ops Date: Tue, 30 Nov 2010 13:07:25 -0600 Message-ID: <20101130190851.727701203@linux.com> References: <20101130190707.457099608@linux.com> Return-path: Content-Disposition: inline; filename=this_cpu_fake_key Sender: linux-kernel-owner@vger.kernel.org To: akpm@linux-foundation.org Cc: Pekka Enberg , William Hubbs , linux-kernel@vger.kernel.org, Eric Dumazet , Mathieu Desnoyers , Tejun Heo , linux-mm@kvack.org List-Id: linux-mm.kvack.org The whole function can be expressed as a simple this_cpu_read() operation. The function overhead is now likely multiple times that of the single instruction that is executed in it. Cc: William Hubbs Signed-off-by: Christoph Lameter --- drivers/staging/speakup/fakekey.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) Index: linux-2.6/drivers/staging/speakup/fakekey.c =================================================================== --- linux-2.6.orig/drivers/staging/speakup/fakekey.c 2010-11-30 12:10:12.000000000 -0600 +++ linux-2.6/drivers/staging/speakup/fakekey.c 2010-11-30 12:14:12.000000000 -0600 @@ -96,10 +96,5 @@ void speakup_fake_down_arrow(void) */ bool speakup_fake_key_pressed(void) { - bool is_pressed; - - is_pressed = get_cpu_var(reporting_keystroke); - put_cpu_var(reporting_keystroke); - - return is_pressed; + return this_cpu_read(reporting_keystroke); }