2009-01-26 20:26:30

by Arnaldo Carvalho de Melo

Subject: [PATCH tip 1/1] blktrace: the ftrace interface needs CONFIG_TRACING

Resend, the first time I forgot to add [PATCH tip 1/1].

Ingo, this fix that problem you reported me, where a .config didn't had
CONFIG_TRACING selected.

Impact: Fix Kconfig selection for blktrace

Also mention in the help text that blktrace now can be used using
the ftrace interface.

Cc: Jens Axboe <[email protected]>
Reported-by: Ingo Molnar <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

diff --git a/block/Kconfig b/block/Kconfig
index 0cbb3b8..7cdaa1d 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -50,6 +50,8 @@ config BLK_DEV_IO_TRACE
select RELAY
select DEBUG_FS
select TRACEPOINTS
+ select TRACING
+ select STACKTRACE
help
Say Y here if you want to be able to trace the block layer actions
on a given queue. Tracing allows you to see any traffic happening
@@ -58,6 +60,12 @@ config BLK_DEV_IO_TRACE

git://git.kernel.dk/blktrace.git

+ Tracing also is possible using the ftrace interface, e.g.:
+
+ echo 1 > /sys/block/sda/sda1/trace/enable
+ echo blk > /sys/kernel/debug/tracing/current_tracer
+ cat /sys/kernel/debug/tracing/trace_pipe
+
If unsure, say N.

config BLK_DEV_BSG

2009-01-26 20:31:57

by Ingo Molnar

Subject: Re: [PATCH tip 1/1] blktrace: the ftrace interface needs CONFIG_TRACING

* Arnaldo Carvalho de Melo <[email protected]> wrote:

> Resend, the first time I forgot to add [PATCH tip 1/1].
>
> Ingo, this fix that problem you reported me, where a .config didn't had
> CONFIG_TRACING selected.

yep - i already applied the first version and it does the trick for the
build failure. (I changed the Impact line to "Impact: build fix" - as that
really is the goal and effect of the commit.)

Thanks,

Ingo