> From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Sent: Friday, April 22, 2022 8:17 PM > To: Linyu Yuan (QUIC) <quic_linyyuan@xxxxxxxxxxx> > Cc: Felipe Balbi <balbi@xxxxxxxxxx>; linux-usb@xxxxxxxxxxxxxxx; Jack Pham > (QUIC) <quic_jackp@xxxxxxxxxxx> > Subject: Re: [PATCH v6 0/5] usb: gadget: configfs: new trace events > > On Fri, Apr 22, 2022 at 09:01:13AM +0000, Linyu Yuan (QUIC) wrote: > > > From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > > Sent: Friday, April 22, 2022 4:43 PM > > > To: Linyu Yuan (QUIC) <quic_linyyuan@xxxxxxxxxxx> > > > Cc: Felipe Balbi <balbi@xxxxxxxxxx>; linux-usb@xxxxxxxxxxxxxxx; Jack > Pham > > > (QUIC) <quic_jackp@xxxxxxxxxxx> > > > Subject: Re: [PATCH v6 0/5] usb: gadget: configfs: new trace events > > > > > > On Thu, Apr 07, 2022 at 09:27:40AM +0800, Linyu Yuan wrote: > > > > Last year I try to add trace event support for usb gadget configfs [1], > > > > this time the idea is change a lot, the purpose is trace all user space > > > > operation to gadget configuration, include gadget and it's function. > > > > > > But why? Who will use this, and what for? > > > > Thanks for review it. > > It is not used by user space, just for kernel gadget issue debugging. > > So you use it in userspace? How can you use a tracepoint from somewhere > else in the kernel? > > > Like android, the user space is complicate to kernel developers, > > With this trace events, kernel development will understand > > What is simplified action happen from user space. > > They do not need this, they can just use ftrace today. Most of these > tracepoints you are putting in here are just for a "got to this > function!" type of thing, which ftrace can show you already. > > What is the added benefit of these over ftrace? Thanks, please discard this changes, will use kprobe event. > > thanks, > > greg k-h
