2021-04-16 06:57:18

by zhaoxiao

Subject: [PATCH v2] X86: Makefile: Replace -pg with CC_FLAGS_FTRACE

In preparation for x86 supporting ftrace built on other compiler
options, let's have the x86 Makefiles remove the $(CC_FLAGS_FTRACE)
flags, whatever these may be, rather than assuming '-pg'.

There should be no functional change as a result of this patch.

Signed-off-by: zhaoxiao <[email protected]>
---
v2: add the same change for the other Makefile in arch/x86 directory.
arch/x86/entry/vdso/Makefile | 8 ++++----
arch/x86/kernel/Makefile | 16 ++++++++--------
arch/x86/kernel/cpu/Makefile | 4 ++--
arch/x86/lib/Makefile | 2 +-
arch/x86/mm/Makefile | 4 ++--
arch/x86/xen/Makefile | 6 +++---
6 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 05c4abc2fdfd..c5bd91bf9f93 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -96,10 +96,10 @@ $(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(
#
# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
#
-CFLAGS_REMOVE_vclock_gettime.o = -pg
-CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg
-CFLAGS_REMOVE_vgetcpu.o = -pg
-CFLAGS_REMOVE_vsgx.o = -pg
+CFLAGS_REMOVE_vclock_gettime.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_vdso32/vclock_gettime.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_vgetcpu.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_vsgx.o = $(CC_FLAGS_FTRACE)

#
# X32 processes use x32 vDSO to access 64bit kernel data.
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 2ddf08351f0b..2811fc6a17ba 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -13,14 +13,14 @@ CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE)

ifdef CONFIG_FUNCTION_TRACER
# Do not profile debug and lowlevel utilities
-CFLAGS_REMOVE_tsc.o = -pg
-CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
-CFLAGS_REMOVE_pvclock.o = -pg
-CFLAGS_REMOVE_kvmclock.o = -pg
-CFLAGS_REMOVE_ftrace.o = -pg
-CFLAGS_REMOVE_early_printk.o = -pg
-CFLAGS_REMOVE_head64.o = -pg
-CFLAGS_REMOVE_sev-es.o = -pg
+CFLAGS_REMOVE_tsc.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_paravirt-spinlocks.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_pvclock.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_kvmclock.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_early_printk.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_head64.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_sev-es.o = $(CC_FLAGS_FTRACE)
endif

KASAN_SANITIZE_head$(BITS).o := n
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 637b499450d1..4435c6de9145 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -5,8 +5,8 @@

# Don't trace early stages of a secondary CPU boot
ifdef CONFIG_FUNCTION_TRACER
-CFLAGS_REMOVE_common.o = -pg
-CFLAGS_REMOVE_perf_event.o = -pg
+CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_perf_event.o = $(CC_FLAGS_FTRACE)
endif

# If these files are instrumented, boot hangs during the first second.
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index bad4dee4f0e4..0aa71b8a5bc1 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -21,7 +21,7 @@ KASAN_SANITIZE_cmdline.o := n
KCSAN_SANITIZE_cmdline.o := n

ifdef CONFIG_FUNCTION_TRACER
-CFLAGS_REMOVE_cmdline.o = -pg
+CFLAGS_REMOVE_cmdline.o = $(CC_FLAGS_FTRACE)
endif

CFLAGS_cmdline.o := -fno-stack-protector -fno-jump-tables
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index 5864219221ca..91883d5a0293 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -12,8 +12,8 @@ KASAN_SANITIZE_mem_encrypt_identity.o := n
KCSAN_SANITIZE := n

ifdef CONFIG_FUNCTION_TRACER
-CFLAGS_REMOVE_mem_encrypt.o = -pg
-CFLAGS_REMOVE_mem_encrypt_identity.o = -pg
+CFLAGS_REMOVE_mem_encrypt.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_mem_encrypt_identity.o = $(CC_FLAGS_FTRACE)
endif

obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o mmap.o \
diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 40b5779fce21..179dfc124c94 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -2,9 +2,9 @@

ifdef CONFIG_FUNCTION_TRACER
# Do not profile debug and lowlevel utilities
-CFLAGS_REMOVE_spinlock.o = -pg
-CFLAGS_REMOVE_time.o = -pg
-CFLAGS_REMOVE_irq.o = -pg
+CFLAGS_REMOVE_spinlock.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_time.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_irq.o = $(CC_FLAGS_FTRACE)
endif

# Make sure early boot has no stackprotector
--
2.20.1

2021-04-16 15:18:12

by Josh Poimboeuf

Subject: Re: [PATCH v2] X86: Makefile: Replace -pg with CC_FLAGS_FTRACE

Adding Steven Rostedt (ftrace maintainer).

On Fri, Apr 16, 2021 at 01:39:28PM +0800, zhaoxiao wrote:
> In preparation for x86 supporting ftrace built on other compiler
> options, let's have the x86 Makefiles remove the $(CC_FLAGS_FTRACE)
> flags, whatever these may be, rather than assuming '-pg'.
>
> There should be no functional change as a result of this patch.
>
> Signed-off-by: zhaoxiao <[email protected]>
> ---
> v2: add the same change for the other Makefile in arch/x86 directory.
> arch/x86/entry/vdso/Makefile | 8 ++++----
> arch/x86/kernel/Makefile | 16 ++++++++--------
> arch/x86/kernel/cpu/Makefile | 4 ++--
> arch/x86/lib/Makefile | 2 +-
> arch/x86/mm/Makefile | 4 ++--
> arch/x86/xen/Makefile | 6 +++---
> 6 files changed, 20 insertions(+), 20 deletions(-)
>
> diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
> index 05c4abc2fdfd..c5bd91bf9f93 100644
> --- a/arch/x86/entry/vdso/Makefile
> +++ b/arch/x86/entry/vdso/Makefile
> @@ -96,10 +96,10 @@ $(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(
> #
> # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
> #
> -CFLAGS_REMOVE_vclock_gettime.o = -pg
> -CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg
> -CFLAGS_REMOVE_vgetcpu.o = -pg
> -CFLAGS_REMOVE_vsgx.o = -pg
> +CFLAGS_REMOVE_vclock_gettime.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_vdso32/vclock_gettime.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_vgetcpu.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_vsgx.o = $(CC_FLAGS_FTRACE)
>
> #
> # X32 processes use x32 vDSO to access 64bit kernel data.
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index 2ddf08351f0b..2811fc6a17ba 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -13,14 +13,14 @@ CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE)
>
> ifdef CONFIG_FUNCTION_TRACER
> # Do not profile debug and lowlevel utilities
> -CFLAGS_REMOVE_tsc.o = -pg
> -CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
> -CFLAGS_REMOVE_pvclock.o = -pg
> -CFLAGS_REMOVE_kvmclock.o = -pg
> -CFLAGS_REMOVE_ftrace.o = -pg
> -CFLAGS_REMOVE_early_printk.o = -pg
> -CFLAGS_REMOVE_head64.o = -pg
> -CFLAGS_REMOVE_sev-es.o = -pg
> +CFLAGS_REMOVE_tsc.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_paravirt-spinlocks.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_pvclock.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_kvmclock.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_early_printk.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_head64.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_sev-es.o = $(CC_FLAGS_FTRACE)
> endif
>
> KASAN_SANITIZE_head$(BITS).o := n
> diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
> index 637b499450d1..4435c6de9145 100644
> --- a/arch/x86/kernel/cpu/Makefile
> +++ b/arch/x86/kernel/cpu/Makefile
> @@ -5,8 +5,8 @@
>
> # Don't trace early stages of a secondary CPU boot
> ifdef CONFIG_FUNCTION_TRACER
> -CFLAGS_REMOVE_common.o = -pg
> -CFLAGS_REMOVE_perf_event.o = -pg
> +CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_perf_event.o = $(CC_FLAGS_FTRACE)
> endif
>
> # If these files are instrumented, boot hangs during the first second.
> diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
> index bad4dee4f0e4..0aa71b8a5bc1 100644
> --- a/arch/x86/lib/Makefile
> +++ b/arch/x86/lib/Makefile
> @@ -21,7 +21,7 @@ KASAN_SANITIZE_cmdline.o := n
> KCSAN_SANITIZE_cmdline.o := n
>
> ifdef CONFIG_FUNCTION_TRACER
> -CFLAGS_REMOVE_cmdline.o = -pg
> +CFLAGS_REMOVE_cmdline.o = $(CC_FLAGS_FTRACE)
> endif
>
> CFLAGS_cmdline.o := -fno-stack-protector -fno-jump-tables
> diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
> index 5864219221ca..91883d5a0293 100644
> --- a/arch/x86/mm/Makefile
> +++ b/arch/x86/mm/Makefile
> @@ -12,8 +12,8 @@ KASAN_SANITIZE_mem_encrypt_identity.o := n
> KCSAN_SANITIZE := n
>
> ifdef CONFIG_FUNCTION_TRACER
> -CFLAGS_REMOVE_mem_encrypt.o = -pg
> -CFLAGS_REMOVE_mem_encrypt_identity.o = -pg
> +CFLAGS_REMOVE_mem_encrypt.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_mem_encrypt_identity.o = $(CC_FLAGS_FTRACE)
> endif
>
> obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o mmap.o \
> diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
> index 40b5779fce21..179dfc124c94 100644
> --- a/arch/x86/xen/Makefile
> +++ b/arch/x86/xen/Makefile
> @@ -2,9 +2,9 @@
>
> ifdef CONFIG_FUNCTION_TRACER
> # Do not profile debug and lowlevel utilities
> -CFLAGS_REMOVE_spinlock.o = -pg
> -CFLAGS_REMOVE_time.o = -pg
> -CFLAGS_REMOVE_irq.o = -pg
> +CFLAGS_REMOVE_spinlock.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_time.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_irq.o = $(CC_FLAGS_FTRACE)
> endif
>
> # Make sure early boot has no stackprotector
> --
> 2.20.1
>
>
>

--
Josh

2021-04-16 20:39:18

by Steven Rostedt

Subject: Re: [PATCH v2] X86: Makefile: Replace -pg with CC_FLAGS_FTRACE

On Fri, 16 Apr 2021 10:12:58 -0500
Josh Poimboeuf <[email protected]> wrote:

> Adding Steven Rostedt (ftrace maintainer).

Thanks.

>
> On Fri, Apr 16, 2021 at 01:39:28PM +0800, zhaoxiao wrote:
> > In preparation for x86 supporting ftrace built on other compiler
> > options, let's have the x86 Makefiles remove the $(CC_FLAGS_FTRACE)
> > flags, whatever these may be, rather than assuming '-pg'.
> >
> > There should be no functional change as a result of this patch.
> >
> > Signed-off-by: zhaoxiao <[email protected]>
> > ---
> > v2: add the same change for the other Makefile in arch/x86 directory.
> > arch/x86/entry/vdso/Makefile | 8 ++++----
> > arch/x86/kernel/Makefile | 16 ++++++++--------
> > arch/x86/kernel/cpu/Makefile | 4 ++--
> > arch/x86/lib/Makefile | 2 +-
> > arch/x86/mm/Makefile | 4 ++--
> > arch/x86/xen/Makefile | 6 +++---
> > 6 files changed, 20 insertions(+), 20 deletions(-)
> >

I'm good with switching "-pg" over to "$(CC_FLAGS_FTRACE)" globally.

Acked-by: Steven Rostedt (VMware) <[email protected]>

-- Steve

2021-04-16 22:11:05

by Thomas Gleixner

Subject: Re: [PATCH v2] X86: Makefile: Replace -pg with CC_FLAGS_FTRACE

On Fri, Apr 16 2021 at 13:39, zhaoxiao wrote:
> In preparation for x86 supporting ftrace built on other compiler
> options, let's have the x86 Makefiles remove the $(CC_FLAGS_FTRACE)
> flags, whatever these may be, rather than assuming '-pg'.

s/let's have the/make the/

> There should be no functional change as a result of this patch.

Should be? Either you know that there is no functional change or not. If
you're unsure why are you posting it at all?

So this wants to be:

No functional change.

Other than that and the fact that this is incomplete as it fails to
catch _all_ instances of -pg in arch/x86 and also leaves stale comments
around I'm ok with the intent.

# git grep '\-pg' arch/x86/
arch/x86/entry/vdso/Makefile:# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
arch/x86/kernel/ftrace_64.S: * gcc -pg option adds a call to 'mcount' in most functions.
arch/x86/purgatory/Makefile:# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
arch/x86/um/vdso/Makefile:# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
arch/x86/um/vdso/Makefile:CFLAGS_REMOVE_vdso-note.o = -pg -fprofile-arcs -ftest-coverage
arch/x86/um/vdso/Makefile:CFLAGS_REMOVE_um_vdso.o = -pg -fprofile-arcs -ftest-coverage

grep is not rocket science ...

Thanks,

tglx