On Mon, Jan 30, 2023 at 11:19:13AM -0700, Ross Zwisler wrote: > The canonical location for the tracefs filesystem is at /sys/kernel/tracing. > > But, from Documentation/trace/ftrace.rst: > > Before 4.1, all ftrace tracing control files were within the debugfs > file system, which is typically located at /sys/kernel/debug/tracing. > For backward compatibility, when mounting the debugfs file system, > the tracefs file system will be automatically mounted at: > > /sys/kernel/debug/tracing > > A few spots in tools/virtio still refer to this older debugfs > path, so let's update them to avoid confusion. > > Signed-off-by: Ross Zwisler <[email protected]> > --- > tools/virtio/virtio-trace/README | 2 +- > tools/virtio/virtio-trace/trace-agent.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/tools/virtio/virtio-trace/README > b/tools/virtio/virtio-trace/README > index b64845b823ab..cea29a2a4c0a 100644 > --- a/tools/virtio/virtio-trace/README > +++ b/tools/virtio/virtio-trace/README > @@ -95,7 +95,7 @@ Run > > 1) Enable ftrace in the guest > <Example> > - # echo 1 > /sys/kernel/debug/tracing/events/sched/enable > + # echo 1 > /sys/kernel/tracing/events/sched/enable > > 2) Run trace agent in the guest > This agent must be operated as root. > diff --git a/tools/virtio/virtio-trace/trace-agent.c > b/tools/virtio/virtio-trace/trace-agent.c > index cdfe77c2b4c8..805942d02e9f 100644 > --- a/tools/virtio/virtio-trace/trace-agent.c > +++ b/tools/virtio/virtio-trace/trace-agent.c > @@ -19,7 +19,7 @@ > #define PIPE_MIN_SIZE (PAGE_SIZE*PIPE_DEF_BUFS) > #define PIPE_MAX_SIZE (1024*1024) > #define READ_PATH_FMT \ > - "/sys/kernel/debug/tracing/per_cpu/cpu%d/trace_pipe_raw" > + "/sys/kernel/tracing/per_cpu/cpu%d/trace_pipe_raw"
Should we try both old and new path then? > #define WRITE_PATH_FMT "/dev/virtio-ports/trace-path-cpu%d" > #define CTL_PATH "/dev/virtio-ports/agent-ctl-path" > > -- > 2.39.1.456.gfc5497dd1b-goog _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
