Re: [RFC][PATCH V2] GCOV: profile by modules

From: Cixi Geng
Date: Wed May 20 2020 - 05:21:32 EST


>> +config SERIAL_GCOV
>> + bool "open gcov for serial"

>What do you mean by "open"? And Kconfig entries are usually Upper Case" :)

>> + depends on GCOV_PROFILE_PREREQS
>> + help
>> + Say Y here to enable gcov in serial.

>I think we need more text here.

Maybe I should use "Enable" instead of "open" for express more clearly.
and I will add more description of SERIAL_GCOV

Cixi Geng <gengcixi@xxxxxxxxx> ä2020å5æ20æåä äå5:04åéï
>
> Thank you for guidances, I will fix error and upload new patch
>
> Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> ä2020å5æ20æåä äå4:51åéï
> >
> > On Wed, May 20, 2020 at 04:38:21PM +0800, gengcixi@xxxxxxxxx wrote:
> > > From: Cixi Geng <cixi.geng1@xxxxxxxxxx>
> > >
> > > ---
> > > Replace symbol GCOV_PROFILE_MODULES with GCOV_PROFILE_PREREQS
> > > ---
> > > The CONFIG_GCOV_PROFILE_ALL will compile kernel by profiling entire
> > > kernel which will lead to kernel run slower.Use GCOV_PROFILE_PREREQS
> > > to control part of the kernel modules to open gcov.
> > >
> > > Only add SERIAL_GCOV for an example.
> > >
> > > Signed-off-by: Cixi Geng <cixi.geng1@xxxxxxxxxx>
> > > ---
> > > drivers/tty/serial/Kconfig | 6 ++++++
> > > drivers/tty/serial/Makefile | 1 +
> > > kernel/gcov/Kconfig | 14 ++++++++++++++
> > > 3 files changed, 21 insertions(+)
> > >
> > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
> > > index adf9e80e7dc9..964df1a2989c 100644
> > > --- a/drivers/tty/serial/Kconfig
> > > +++ b/drivers/tty/serial/Kconfig
> > > @@ -1566,3 +1566,9 @@ endmenu
> > >
> > > config SERIAL_MCTRL_GPIO
> > > tristate
> > > +
> > > +config SERIAL_GCOV
> > > + bool "open gcov for serial"
> >
> > What do you mean by "open"? And Kconfig entries are usually Upper Case" :)
> >
> > > + depends on GCOV_PROFILE_PREREQS
> > > + help
> > > + Say Y here to enable gcov in serial.
> >
> > I think we need more text here.
> >
> >
> > > diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
> > > index d056ee6cca33..7be1202286d2 100644
> > > --- a/drivers/tty/serial/Makefile
> > > +++ b/drivers/tty/serial/Makefile
> > > @@ -2,6 +2,7 @@
> > > #
> > > # Makefile for the kernel serial device drivers.
> > > #
> > > +GCOV_PROFILE := $(CONFIG_SERIAL_GCOV)
> > >
> > > obj-$(CONFIG_SERIAL_CORE) += serial_core.o
> > >
> > > diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
> > > index 3941a9c48f83..91cc8f3c7c43 100644
> > > --- a/kernel/gcov/Kconfig
> > > +++ b/kernel/gcov/Kconfig
> > > @@ -51,6 +51,20 @@ config GCOV_PROFILE_ALL
> > > larger and run slower. Also be sure to exclude files from profiling
> > > which are not linked to the kernel image to prevent linker errors.
> > >
> > > +config GCOV_PROFILE_PREREQS
> > > + bool "Profile Kernel subsytem"
> > > + depends on !COMPILE_TEST
> > > + depends on GCOV_KERNEL
> > > + default n
> >
> > default is always 'n', no need to list that
> >
> > > + help
> > > + This options activates profiling for the specified kernel modules.
> > > +
> > > + If unsure, say N.
> > > +
> > > + When some modules need Gcov data, enable this config, then configure
> > > + with gcov on the corresponding modules configs.The directories or files
> >
> > '. '?
> >
> > > + of these modules will be added profiling flags after kernel compile.
> >
> > The lines under "help" need to be indented more, right?
> >
> > thanks,
> >
> > greg k-h