From 1d54ad6da9192fed5dd3b60224d9f2dfea0dcd82 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Tue, 14 Apr 2009 14:00:05 +0800 Subject: blktrace: add trace/ to /sys/block/sda 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 Acked-by: "Theodore Ts'o" Cc: Arnaldo Carvalho de Melo Cc: Shawn Du Cc: Jens Axboe LKML-Reference: <49E42665.6020506@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- kernel/trace/blktrace.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'kernel/trace/blktrace.c') diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index d10989880520..8e7c5da3a3e6 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); +} + -- cgit v1.2.3