diff options
| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2009-01-26 16:00:40 -0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-01-27 14:30:36 +0100 |
| commit | 32c0bd9624115041cfec31c0436995418083090a (patch) | |
| tree | 833dfe1e19338721d1043a2ecfa96a40703c0749 | |
| parent | 157f9c00e88529ed84bd7d581a40d411e5414cf0 (diff) | |
blktrace: the ftrace interface needs CONFIG_TRACING
Impact: build fix
Also mention in the help text that blktrace now can be used using
the ftrace interface.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | block/Kconfig | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/block/Kconfig b/block/Kconfig index 0cbb3b88b59..7cdaa1d7225 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 |