Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753582AbZDNF72 (ORCPT ); Tue, 14 Apr 2009 01:59:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751300AbZDNF7R (ORCPT ); Tue, 14 Apr 2009 01:59:17 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:63872 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751863AbZDNF7Q (ORCPT ); Tue, 14 Apr 2009 01:59:16 -0400 Message-ID: <49E42665.6020506@cn.fujitsu.com> Date: Tue, 14 Apr 2009 14:00:05 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Ingo Molnar , Jens Axboe CC: Arnaldo Carvalho de Melo , "Theodore Ts'o" , Shawn Du , LKML , linux-btrace@vger.kernel.org Subject: [PATCH 3/3] blktrace: add trace/ to /sys/block/sda References: <49E42620.4050701@cn.fujitsu.com> In-Reply-To: <49E42620.4050701@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2911 Lines: 98 Impact: allow ftrace-plugin blktrace to trace device-mapper devices To trace a single partition: # echo 1 > /sys/block/sda/sda1/enable To trace the whole sda instead: # echo 1 > /sys/block/sda/enable Thus we also fix an issue reported by Ted, that ftrace-plugin blktrace can't be used to trace device-mapper devices. Now: # echo 1 > /sys/block/dm-0/trace/enable echo: write error: No such device or address # mount -t ext4 /dev/dm-0 /mnt # echo 1 > /sys/block/dm-0/trace/enable # echo blk > /debug/tracing/current_tracer Reported-by: Theodore Tso Signed-off-by: Li Zefan --- block/blk-sysfs.c | 7 ++++++- include/linux/blktrace_api.h | 6 ++++++ kernel/trace/blktrace.c | 5 +++++ 3 files changed, 17 insertions(+), 1 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 73f36be..8653d71 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -387,16 +387,21 @@ struct kobj_type blk_queue_ktype = { int blk_register_queue(struct gendisk *disk) { int ret; + struct device *dev = disk_to_dev(disk); struct request_queue *q = disk->queue; if (WARN_ON(!q)) return -ENXIO; + ret = blk_trace_init_sysfs(dev); + if (ret) + return ret; + if (!q->request_fn) return 0; - ret = kobject_add(&q->kobj, kobject_get(&disk_to_dev(disk)->kobj), + ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue"); if (ret < 0) return ret; diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 6b2c87e..b5d1ca4 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -198,6 +198,7 @@ extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, char __user *arg); extern int blk_trace_startstop(struct request_queue *q, int start); extern int blk_trace_remove(struct request_queue *q); +extern int blk_trace_init_sysfs(struct device *dev); extern struct attribute_group blk_trace_attr_group; @@ -211,6 +212,11 @@ extern struct attribute_group blk_trace_attr_group; #define blk_trace_remove(q) (-ENOTTY) #define blk_add_trace_msg(q, fmt, ...) do { } while (0) +static inline int blk_trace_init_sysfs(struct device *dev) +{ + return 0; +} + #endif /* CONFIG_BLK_DEV_IO_TRACE */ #endif /* __KERNEL__ */ #endif diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index d109898..8e7c5da 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -1644,3 +1644,8 @@ out: return ret ? ret : count; } +int blk_trace_init_sysfs(struct device *dev) +{ + return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); +} + -- 1.5.4.rc3 -- 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/