kbuild: trace functions in subdirectories of lib/

ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)

exists here in sub-directories of lib/ to keep the behavior of
commit 2464a60 ("ftrace: do not trace library functions").

Since that commit, not only the objects in lib/ but also the ones in
the sub-directories are excluded from ftrace (although the commit
description did not explicitly mention this).

However, most of library functions in sub-directories are not so hot.
Re-add them to ftrace.

Going forward, only the objects right under lib/ will be excluded.

Cc: Ingo Molnar <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Steven Rostedt (VMware) <[email protected]>

Author: masahir0y

lib/842/Makefile

@@ -1,6 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
-
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 obj-$(CONFIG_842_COMPRESS) += 842_compress.o
 obj-$(CONFIG_842_DECOMPRESS) += 842_decompress.o

lib/crypto/Makefile

@@ -1,7 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 # chacha is used by the /dev/random driver which is always builtin
 obj-y						+= chacha.o
 obj-$(CONFIG_CRYPTO_LIB_CHACHA_GENERIC)		+= libchacha.o

lib/dim/Makefile

@@ -2,8 +2,6 @@
 # DIM Dynamic Interrupt Moderation library
 #
 
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 obj-$(CONFIG_DIMLIB) += dim.o
 
 dim-y := dim.o net_dim.o rdma_dim.o

lib/fonts/Makefile

@@ -1,8 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 # Font handling
 
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 font-objs := fonts.o
 
 font-objs-$(CONFIG_FONT_SUN8x16)   += font_sun8x16.o

lib/kunit/Makefile

@@ -1,6 +1,3 @@
-
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 obj-$(CONFIG_KUNIT) +=			kunit.o
 
 kunit-objs +=				test.o \

lib/livepatch/Makefile

@@ -2,8 +2,6 @@
 #
 # Makefile for livepatch test code.
 
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 obj-$(CONFIG_TEST_LIVEPATCH) += test_klp_atomic_replace.o \
 				test_klp_callbacks_demo.o \
 				test_klp_callbacks_demo2.o \
@@ -14,7 +12,3 @@ obj-$(CONFIG_TEST_LIVEPATCH) += test_klp_atomic_replace.o \
 				test_klp_state.o \
 				test_klp_state2.o \
 				test_klp_state3.o
-
-# Target modules to be livepatched require CC_FLAGS_FTRACE
-CFLAGS_test_klp_callbacks_busy.o	+= $(CC_FLAGS_FTRACE)
-CFLAGS_test_klp_callbacks_mod.o		+= $(CC_FLAGS_FTRACE)

lib/lz4/Makefile

@@ -1,6 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
 ccflags-y += -O3
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
 
 obj-$(CONFIG_LZ4_COMPRESS) += lz4_compress.o
 obj-$(CONFIG_LZ4HC_COMPRESS) += lz4hc_compress.o

lib/lzo/Makefile

@@ -1,6 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 lzo_compress-objs := lzo1x_compress.o
 lzo_decompress-objs := lzo1x_decompress_safe.o
 

lib/math/Makefile

@@ -1,6 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 obj-y += div64.o gcd.o lcm.o int_pow.o int_sqrt.o reciprocal_div.o
 
 obj-$(CONFIG_CORDIC)		+= cordic.o

lib/mpi/Makefile

@@ -3,8 +3,6 @@
 # MPI multiprecision maths library (from gpg)
 #
 
-ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)
-
 obj-$(CONFIG_MPILIB) = mpi.o
 
 mpi-y = \