This allows gcov to be enabled for a particular kernel source
subdirectory on the command line, without editing makefiles, like so:
make GCOV_PROFILE_fs_bcachefs=y
Cc: Masahiro Yamada <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Nicolas Schier <[email protected]>
Cc: [email protected]
Signed-off-by: Kent Overstreet <[email protected]>
---
scripts/Kbuild.include | 10 ++++++++++
scripts/Makefile.lib | 2 +-
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 7778cc97a4e0..5341736f2e30 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -277,3 +277,13 @@ ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VER
else
.SECONDARY:
endif
+
+ # expand_parents(a/b/c) = a/b/c a/b a
+expand_parents2 = $(if $(subst .,,$(1)),$(call expand_parents,$(1)),)
+expand_parents = $(1) $(call expand_parents2,$(patsubst %/,%,$(dir $(1))))
+
+# flatten_dirs(a/b/c) = a_b_c a_b a
+flatten_dirs = $(subst /,_,$(call expand_parents,$(1)))
+
+# eval_vars(X_,a/b/c) = $(X_a_b_c) $(X_a_b) $(X_a)
+eval_vars = $(foreach var,$(call flatten_dirs,$(2)),$($(1)$(var)))
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 1a965fe68e01..0b4581a8bc33 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -148,7 +148,7 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
#
ifeq ($(CONFIG_GCOV_KERNEL),y)
_c_flags += $(if $(patsubst n%,, \
- $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
+ $(GCOV_PROFILE_$(basetarget).o)$(call eval_vars,GCOV_PROFILE_,$(src))$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
$(CFLAGS_GCOV))
endif
--
2.42.0
On Thu, Nov 23, 2023 at 8:55 AM Kent Overstreet
<[email protected]> wrote:
>
> This allows gcov to be enabled for a particular kernel source
> subdirectory on the command line, without editing makefiles, like so:
>
> make GCOV_PROFILE_fs_bcachefs=y
>
> Cc: Masahiro Yamada <[email protected]>
> Cc: Nathan Chancellor <[email protected]>
> Cc: Nick Desaulniers <[email protected]>
> Cc: Nicolas Schier <[email protected]>
> Cc: [email protected]
> Signed-off-by: Kent Overstreet <[email protected]>
> ---
> scripts/Kbuild.include | 10 ++++++++++
> scripts/Makefile.lib | 2 +-
> 2 files changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> index 7778cc97a4e0..5341736f2e30 100644
> --- a/scripts/Kbuild.include
> +++ b/scripts/Kbuild.include
> @@ -277,3 +277,13 @@ ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VER
> else
> .SECONDARY:
> endif
> +
> + # expand_parents(a/b/c) = a/b/c a/b a
> +expand_parents2 = $(if $(subst .,,$(1)),$(call expand_parents,$(1)),)
> +expand_parents = $(1) $(call expand_parents2,$(patsubst %/,%,$(dir $(1))))
> +
> +# flatten_dirs(a/b/c) = a_b_c a_b a
> +flatten_dirs = $(subst /,_,$(call expand_parents,$(1)))
> +
> +# eval_vars(X_,a/b/c) = $(X_a_b_c) $(X_a_b) $(X_a)
> +eval_vars = $(foreach var,$(call flatten_dirs,$(2)),$($(1)$(var)))
I do not like tricky code like this.
Also, with "fs_bcachefs", it is unclear which directory
is enabled.
How about this?
[1] Specify the list of directories by GCOV_PROFILE_DIRS
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 1a965fe68e01..286a569556b3 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -147,8 +147,12 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y)
$(CPPFLAGS_$(target-stem).lds)
# (in this order)
#
ifeq ($(CONFIG_GCOV_KERNEL),y)
+ifneq ($(filter $(obj),$(GCOV_PROFILE_DIRS)),)
+export GCOV_PROFILE_SUBDIR := y
+endif
+
_c_flags += $(if $(patsubst n%,, \
-
$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)),
\
+
$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(GCOV_PROFILE_SUBDIR)$(CONFIG_GCOV_PROFILE_ALL)),
\
$(CFLAGS_GCOV))
endif
Usage:
$ make GCOV_PROFILE_DIRS=fs/bcachefs
-> enable GCOV in fs/bachefs and its subdirectories.
or
$ make GCOV_PROFILE_DIRS="drivers/gpio drivers/pinctrl"
-> enable GCOV in drivers/gpio, drivers/pinctrl, and their subdirectories.
[2] Do equivalent, but from a CONFIG option
config GCOV_PROFILE_DIRS
string "Directories to enable GCOV"
Then, you can set CONFIG_GCOV_PROFILE_DIRS="fs/bcachefs"
This might be a more natural approach because we already have
CONFIG_GCOV_PROFILE_ALL, although it might eventually go away
because CONFIG_GCOV_PROFILE_ALL=y is almost equivalent to
CONFIG_GCOV_PROFILE_DIRS="."
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 1a965fe68e01..286a569556b3 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -147,8 +147,12 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y)
$(CPPFLAGS_$(target-stem).lds)
# (in this order)
#
ifeq ($(CONFIG_GCOV_KERNEL),y)
+ifneq ($(filter $(obj),$(CONFIG_GCOV_PROFILE_DIRS)),)
+export GCOV_PROFILE_SUBDIR := y
+endif
+
_c_flags += $(if $(patsubst n%,, \
-
$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)),
\
+
$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(GCOV_PROFILE_SUBDIR)$(CONFIG_GCOV_PROFILE_ALL)),
\
$(CFLAGS_GCOV))
endif
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 1a965fe68e01..0b4581a8bc33 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -148,7 +148,7 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
> #
> ifeq ($(CONFIG_GCOV_KERNEL),y)
> _c_flags += $(if $(patsubst n%,, \
> - $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
> + $(GCOV_PROFILE_$(basetarget).o)$(call eval_vars,GCOV_PROFILE_,$(src))$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
> $(CFLAGS_GCOV))
> endif
>
> --
> 2.42.0
>
--
Best Regards
Masahiro Yamada
On Fri, Nov 24, 2023 at 11:02:00AM +0900, Masahiro Yamada wrote:
> On Thu, Nov 23, 2023 at 8:55 AM Kent Overstreet
> <[email protected]> wrote:
> >
> > This allows gcov to be enabled for a particular kernel source
> > subdirectory on the command line, without editing makefiles, like so:
> >
> > make GCOV_PROFILE_fs_bcachefs=y
> >
> > Cc: Masahiro Yamada <[email protected]>
> > Cc: Nathan Chancellor <[email protected]>
> > Cc: Nick Desaulniers <[email protected]>
> > Cc: Nicolas Schier <[email protected]>
> > Cc: [email protected]
> > Signed-off-by: Kent Overstreet <[email protected]>
> > ---
> > scripts/Kbuild.include | 10 ++++++++++
> > scripts/Makefile.lib | 2 +-
> > 2 files changed, 11 insertions(+), 1 deletion(-)
> >
> > diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> > index 7778cc97a4e0..5341736f2e30 100644
> > --- a/scripts/Kbuild.include
> > +++ b/scripts/Kbuild.include
> > @@ -277,3 +277,13 @@ ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VER
> > else
> > .SECONDARY:
> > endif
> > +
> > + # expand_parents(a/b/c) = a/b/c a/b a
> > +expand_parents2 = $(if $(subst .,,$(1)),$(call expand_parents,$(1)),)
> > +expand_parents = $(1) $(call expand_parents2,$(patsubst %/,%,$(dir $(1))))
> > +
> > +# flatten_dirs(a/b/c) = a_b_c a_b a
> > +flatten_dirs = $(subst /,_,$(call expand_parents,$(1)))
> > +
> > +# eval_vars(X_,a/b/c) = $(X_a_b_c) $(X_a_b) $(X_a)
> > +eval_vars = $(foreach var,$(call flatten_dirs,$(2)),$($(1)$(var)))
>
>
>
> I do not like tricky code like this.
>
> Also, with "fs_bcachefs", it is unclear which directory
> is enabled.
It's consistent with how we can specify options in makefiles for a
particular file.
I suppose CONFIG_GCOV_PROFILE_DIRS would be fine, but your patch isn't
complete so I can't test it.
>
>
>
>
> How about this?
>
>
>
> [1] Specify the list of directories by GCOV_PROFILE_DIRS
>
>
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 1a965fe68e01..286a569556b3 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -147,8 +147,12 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y)
> $(CPPFLAGS_$(target-stem).lds)
> # (in this order)
> #
> ifeq ($(CONFIG_GCOV_KERNEL),y)
> +ifneq ($(filter $(obj),$(GCOV_PROFILE_DIRS)),)
> +export GCOV_PROFILE_SUBDIR := y
> +endif
> +
> _c_flags += $(if $(patsubst n%,, \
> -
> $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)),
> \
> +
> $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(GCOV_PROFILE_SUBDIR)$(CONFIG_GCOV_PROFILE_ALL)),
> \
> $(CFLAGS_GCOV))
> endif
>
>
>
> Usage:
>
> $ make GCOV_PROFILE_DIRS=fs/bcachefs
>
> -> enable GCOV in fs/bachefs and its subdirectories.
>
> or
>
> $ make GCOV_PROFILE_DIRS="drivers/gpio drivers/pinctrl"
>
> -> enable GCOV in drivers/gpio, drivers/pinctrl, and their subdirectories.
>
>
>
>
> [2] Do equivalent, but from a CONFIG option
>
>
> config GCOV_PROFILE_DIRS
> string "Directories to enable GCOV"
>
>
> Then, you can set CONFIG_GCOV_PROFILE_DIRS="fs/bcachefs"
>
>
> This might be a more natural approach because we already have
> CONFIG_GCOV_PROFILE_ALL, although it might eventually go away
> because CONFIG_GCOV_PROFILE_ALL=y is almost equivalent to
> CONFIG_GCOV_PROFILE_DIRS="."
>
>
>
>
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 1a965fe68e01..286a569556b3 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -147,8 +147,12 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y)
> $(CPPFLAGS_$(target-stem).lds)
> # (in this order)
> #
> ifeq ($(CONFIG_GCOV_KERNEL),y)
> +ifneq ($(filter $(obj),$(CONFIG_GCOV_PROFILE_DIRS)),)
> +export GCOV_PROFILE_SUBDIR := y
> +endif
> +
> _c_flags += $(if $(patsubst n%,, \
> -
> $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)),
> \
> +
> $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(GCOV_PROFILE_SUBDIR)$(CONFIG_GCOV_PROFILE_ALL)),
> \
> $(CFLAGS_GCOV))
> endif
>
>
>
>
>
>
>
> > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> > index 1a965fe68e01..0b4581a8bc33 100644
> > --- a/scripts/Makefile.lib
> > +++ b/scripts/Makefile.lib
> > @@ -148,7 +148,7 @@ _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
> > #
> > ifeq ($(CONFIG_GCOV_KERNEL),y)
> > _c_flags += $(if $(patsubst n%,, \
> > - $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
> > + $(GCOV_PROFILE_$(basetarget).o)$(call eval_vars,GCOV_PROFILE_,$(src))$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
> > $(CFLAGS_GCOV))
> > endif
> >
> > --
> > 2.42.0
> >
>
>
> --
> Best Regards
> Masahiro Yamada
On Sun, Nov 26, 2023 at 4:56 AM Kent Overstreet
<[email protected]> wrote:
>
> On Fri, Nov 24, 2023 at 11:02:00AM +0900, Masahiro Yamada wrote:
> > On Thu, Nov 23, 2023 at 8:55 AM Kent Overstreet
> > <[email protected]> wrote:
> > >
> > > This allows gcov to be enabled for a particular kernel source
> > > subdirectory on the command line, without editing makefiles, like so:
> > >
> > > make GCOV_PROFILE_fs_bcachefs=y
> > >
> > > Cc: Masahiro Yamada <[email protected]>
> > > Cc: Nathan Chancellor <[email protected]>
> > > Cc: Nick Desaulniers <[email protected]>
> > > Cc: Nicolas Schier <[email protected]>
> > > Cc: [email protected]
> > > Signed-off-by: Kent Overstreet <[email protected]>
> > > ---
> > > scripts/Kbuild.include | 10 ++++++++++
> > > scripts/Makefile.lib | 2 +-
> > > 2 files changed, 11 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> > > index 7778cc97a4e0..5341736f2e30 100644
> > > --- a/scripts/Kbuild.include
> > > +++ b/scripts/Kbuild.include
> > > @@ -277,3 +277,13 @@ ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VER
> > > else
> > > .SECONDARY:
> > > endif
> > > +
> > > + # expand_parents(a/b/c) = a/b/c a/b a
> > > +expand_parents2 = $(if $(subst .,,$(1)),$(call expand_parents,$(1)),)
> > > +expand_parents = $(1) $(call expand_parents2,$(patsubst %/,%,$(dir $(1))))
> > > +
> > > +# flatten_dirs(a/b/c) = a_b_c a_b a
> > > +flatten_dirs = $(subst /,_,$(call expand_parents,$(1)))
> > > +
> > > +# eval_vars(X_,a/b/c) = $(X_a_b_c) $(X_a_b) $(X_a)
> > > +eval_vars = $(foreach var,$(call flatten_dirs,$(2)),$($(1)$(var)))
> >
> >
> >
> > I do not like tricky code like this.
> >
> > Also, with "fs_bcachefs", it is unclear which directory
> > is enabled.
>
> It's consistent with how we can specify options in makefiles for a
> particular file.
It is consistent in a bad way.
You used "GCOV_PROFILE_" prefix
for the full directory path, while it is already
used as a file name which is relative to the
current directory.
>
> I suppose CONFIG_GCOV_PROFILE_DIRS would be fine, but your patch isn't
> complete so I can't test it.
I do not understand what you mean by "isn't complete".
It is just a matter of adding the config entry somewhere.
I added a patch just in case, though.
Note, both approach pros and cons.
The command line approach works for external modules.
With the CONFIG option approach, you can easily see
which directories are profiled by checking the .config,
but it is not easy to enable gcov for external modules.
--
Best Regards
Masahiro Yamada
On Tue, Nov 28, 2023 at 08:44:11PM +0900, Masahiro Yamada wrote:
> On Sun, Nov 26, 2023 at 4:56 AM Kent Overstreet
> > It's consistent with how we can specify options in makefiles for a
> > particular file.
>
>
> It is consistent in a bad way.
That's a new meaning for consistent that I'm unfamiliar with.
> You used "GCOV_PROFILE_" prefix
> for the full directory path, while it is already
> used as a file name which is relative to the
> current directory.
And the current directory when you're building the entire kernel is the
top level directory.
> > I suppose CONFIG_GCOV_PROFILE_DIRS would be fine, but your patch isn't
> > complete so I can't test it.
>
>
> I do not understand what you mean by "isn't complete".
>
> It is just a matter of adding the config entry somewhere.
Yes, not complete, meaning you haven't even tested it.