Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754596Ab2KMBxO (ORCPT ); Mon, 12 Nov 2012 20:53:14 -0500 Received: from mail-pa0-f46.google.com ([209.85.220.46]:64882 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752751Ab2KMBxM (ORCPT ); Mon, 12 Nov 2012 20:53:12 -0500 Message-ID: <50A1A800.3020102@gmail.com> Date: Tue, 13 Nov 2012 09:53:04 +0800 From: Shan Wei User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:16.0) Gecko/20121026 Thunderbird/16.0.2 MIME-Version: 1.0 To: rostedt@goodmis.org, fweisbec@gmail.com, Kernel-Maillist , mingo@redhat.com, cl@linux-foundation.org, Shan Wei Subject: [PATCH v4 7/9] trace: use this_cpu_ptr per-cpu helper Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1976 Lines: 60 From: Shan Wei typeof(&buffer) is a pointer to array of 1024 char, or char (*)[1024]. But, typeof(&buffer[0]) is a pointer to char which match the return type of get_trace_buf(). As well-known, the value of &buffer is equal to &buffer[0]. so return this_cpu_ptr(&percpu_buffer->buffer[0]) can avoid type cast. Signed-off-by: Shan Wei --- v4: avoid type cast using &percpu_buffer->buffer[0]. --- kernel/trace/blktrace.c | 2 +- kernel/trace/trace.c | 5 +---- 2 files changed, 2 insertions(+), 5 deletions(-) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index c0bd030..71259e2 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -147,7 +147,7 @@ void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) return; local_irq_save(flags); - buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); + buf = this_cpu_ptr(bt->msg_data); va_start(args, fmt); n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); va_end(args); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 31e4f55..65cb003 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1495,7 +1495,6 @@ static struct trace_buffer_struct *trace_percpu_nmi_buffer; static char *get_trace_buf(void) { struct trace_buffer_struct *percpu_buffer; - struct trace_buffer_struct *buffer; /* * If we have allocated per cpu buffers, then we do not @@ -1513,9 +1512,7 @@ static char *get_trace_buf(void) if (!percpu_buffer) return NULL; - buffer = per_cpu_ptr(percpu_buffer, smp_processor_id()); - - return buffer->buffer; + return this_cpu_ptr(&percpu_buffer->buffer[0]); } static int alloc_percpu_trace_buffer(void) -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/