rtla: Add libsubcmd dependency

In preparation for migrating RTLA to libsubcmd, build libsubcmd from the
appropriate directory next to the RTLA build proper, and link the
resulting object to RTLA.

libsubcmd uses str_error_r() and strlcpy() at several places. To support
these, also link the respective libraries from tools/lib.

For completeness, also add tools/include to include path. This will
allow other userspace functions and macros shipped with the kernel to be
used in RTLA; perf and bpftool, two other users of libsubcmd, already do
that.

To prevent a name conflict, rename RTLA's run_command() function to
run_tool_command(), and replace RTLA's own container_of implementation
with the one in tools/include/linux/container_of.h.

Assisted-by: Composer:composer-1
Link: https://lore.kernel.org/r/20260528103254.2990068-2-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>

diff --git a/tools/tracing/rtla/.gitignore b/tools/tracing/rtla/.gitignore
index 231fb8d67f9790fb6f5b86934c74a3828e3da6be..c7b4bf1c8ba9b6d4a3667add50863b444cc1140d 100644 (file)
--- a/tools/tracing/rtla/.gitignore
+++ b/tools/tracing/rtla/.gitignore
@@ -10,3 +10,5 @@ custom_filename.txt
 osnoise_irq_noise_hist.txt
 osnoise_trace.txt
 timerlat_trace.txt
+libsubcmd/
+lib/

diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile
index 45690ee14544dfb9648dbafe5132b8c46a44d3ea..60a1025389881cf1a459a0f2400019df567aa0ce 100644 (file)
--- a/tools/tracing/rtla/Makefile
+++ b/tools/tracing/rtla/Makefile
@@ -27,6 +27,30 @@ endif
 RTLA           := $(OUTPUT)rtla
 RTLA_IN                := $(RTLA)-in.o
 
+LIBSUBCMD_DIR = $(srctree)/tools/lib/subcmd/
+ifneq ($(OUTPUT),)
+  LIBSUBCMD_OUTPUT = $(abspath $(OUTPUT))/libsubcmd
+else
+  LIBSUBCMD_OUTPUT = $(CURDIR)/libsubcmd
+endif
+LIBSUBCMD = $(LIBSUBCMD_OUTPUT)/libsubcmd.a
+LIBSUBCMD_INCLUDES = $(LIBSUBCMD_OUTPUT)/include
+LIBSUBCMD_MAKEFLAGS = O=$(LIBSUBCMD_OUTPUT) DESTDIR=$(LIBSUBCMD_OUTPUT) prefix= subdir=
+
+TOOLS_INCLUDES = -I$(srctree)/tools/include
+
+ifneq ($(OUTPUT),)
+  LIB_OUTPUT = $(abspath $(OUTPUT))/lib
+else
+  LIB_OUTPUT = $(CURDIR)/lib
+endif
+
+LIB_STRING = $(LIB_OUTPUT)/string.o
+LIB_STRING_SRC = $(srctree)/tools/lib/string.c
+
+LIB_STR_ERROR_R = $(LIB_OUTPUT)/str_error_r.o
+LIB_STR_ERROR_R_SRC = $(srctree)/tools/lib/str_error_r.c
+
 VERSION                := $(shell sh -c "make -sC ../../.. kernelversion | grep -v make")
 DOCSRC         := ../../../Documentation/tools/rtla/
 
@@ -66,7 +90,7 @@ ifeq ($(config),1)
   include Makefile.config
 endif
 
-CFLAGS         += $(INCLUDES) $(LIB_INCLUDES)
+CFLAGS         += $(INCLUDES) $(LIB_INCLUDES) $(TOOLS_INCLUDES) -I$(LIBSUBCMD_INCLUDES)
 
 export CFLAGS OUTPUT srctree
 
@@ -93,20 +117,48 @@ tests/bpf/bpf_action_map.o: tests/bpf/bpf_action_map.c
        $(Q)echo "BPF skeleton support is disabled, skipping tests/bpf/bpf_action_map.o"
 endif
 
-$(RTLA): $(RTLA_IN)
-       $(QUIET_LINK)$(CC) $(LDFLAGS) -o $(RTLA) $(RTLA_IN) $(EXTLIBS)
+$(RTLA): $(RTLA_IN) $(LIBSUBCMD) $(LIB_STRING) $(LIB_STR_ERROR_R)
+       $(QUIET_LINK)$(CC) $(LDFLAGS) -o $(RTLA) $(RTLA_IN) $(LIBSUBCMD) $(LIB_STRING) $(LIB_STR_ERROR_R) $(EXTLIBS)
 
-static: $(RTLA_IN)
+static: $(RTLA_IN) $(LIBSUBCMD) $(LIB_STRING) $(LIB_STR_ERROR_R)
        $(eval LDFLAGS += -static)
-       $(QUIET_LINK)$(CC) -static $(LDFLAGS) -o $(RTLA)-static $(RTLA_IN)  $(EXTLIBS)
+       $(QUIET_LINK)$(CC) -static $(LDFLAGS) -o $(RTLA)-static $(RTLA_IN) $(LIBSUBCMD) $(LIB_STRING) $(LIB_STR_ERROR_R) $(EXTLIBS)
 
 rtla.%: fixdep FORCE
        make -f $(srctree)/tools/build/Makefile.build dir=. $@
 
-$(RTLA_IN): fixdep FORCE src/timerlat.skel.h
+$(RTLA_IN): fixdep FORCE src/timerlat.skel.h $(LIBSUBCMD_INCLUDES)
        make $(build)=rtla
 
-clean: doc_clean fixdep-clean
+$(LIBSUBCMD_OUTPUT):
+       $(Q)$(MKDIR) -p $@
+
+$(LIBSUBCMD_INCLUDES): FORCE | $(LIBSUBCMD_OUTPUT)
+       $(Q)$(MAKE) -C $(LIBSUBCMD_DIR) $(LIBSUBCMD_MAKEFLAGS) \
+               install_headers
+
+$(LIBSUBCMD): FORCE | $(LIBSUBCMD_OUTPUT)
+       $(Q)$(MAKE) -C $(LIBSUBCMD_DIR) $(LIBSUBCMD_MAKEFLAGS) \
+               $@
+
+$(LIB_OUTPUT):
+       $(Q)$(MKDIR) -p $@
+
+$(LIB_STR_ERROR_R): $(LIB_STR_ERROR_R_SRC) | $(LIB_OUTPUT)
+       $(QUIET_CC)$(CC) $(CFLAGS) -c -o $@ $<
+
+$(LIB_STRING): $(LIB_STRING_SRC) | $(LIB_OUTPUT)
+       $(QUIET_CC)$(CC) $(CFLAGS) -c -o $@ $<
+
+libsubcmd-clean:
+       $(call QUIET_CLEAN, libsubcmd)
+       $(Q)$(RM) -r -- $(LIBSUBCMD_OUTPUT)
+
+lib-clean:
+       $(call QUIET_CLEAN, lib)
+       $(Q)$(RM) -r -- $(LIB_OUTPUT)
+
+clean: doc_clean fixdep-clean libsubcmd-clean lib-clean
        $(call QUIET_CLEAN, rtla)
        $(Q)find . -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
        $(Q)rm -f rtla rtla-static fixdep FEATURE-DUMP rtla-*

diff --git a/tools/tracing/rtla/src/rtla.c b/tools/tracing/rtla/src/rtla.c
index 3398250076ea11140bf51540f2849285f28c8c16..f4342ca684c38ee69bbc5c1c55e780d23b218a38 100644 (file)
--- a/tools/tracing/rtla/src/rtla.c
+++ b/tools/tracing/rtla/src/rtla.c
@@ -38,12 +38,12 @@ static void rtla_usage(int err)
 }
 
 /*
- * run_command - try to run a rtla tool command
+ * run_tool_command - try to run a rtla tool command
  *
  * It returns 0 if it fails. The tool's main will generally not
  * return as they should call exit().
  */
-int run_command(int argc, char **argv, int start_position)
+int run_tool_command(int argc, char **argv, int start_position)
 {
        if (strcmp(argv[start_position], "osnoise") == 0) {
                osnoise_main(argc-start_position, &argv[start_position]);
@@ -69,7 +69,7 @@ int main(int argc, char *argv[])
        int retval;
 
        /* is it an alias? */
-       retval = run_command(argc, argv, 0);
+       retval = run_tool_command(argc, argv, 0);
        if (retval)
                exit(0);
 
@@ -82,7 +82,7 @@ int main(int argc, char *argv[])
                rtla_usage(0);
        }
 
-       retval = run_command(argc, argv, 1);
+       retval = run_tool_command(argc, argv, 1);
        if (retval)
                exit(0);
 

diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h
index e794ede64b2c8a59e0480e1e1533ad98577e7e5f..96fd7204271746b87a99ba8a14432161637ae599 100644 (file)
--- a/tools/tracing/rtla/src/utils.h
+++ b/tools/tracing/rtla/src/utils.h
@@ -7,6 +7,8 @@
 #include <stdbool.h>
 #include <stdlib.h>
 
+#include <linux/container_of.h>
+
 /*
  * '18446744073709551615\0'
  */
@@ -37,10 +39,6 @@ static inline bool str_has_prefix(const char *str, const char *prefix)
        return strncmp(str, prefix, strlen(prefix)) == 0;
 }
 
-#define container_of(ptr, type, member)({                      \
-       const typeof(((type *)0)->member) *__mptr = (ptr);      \
-       (type *)((char *)__mptr - offsetof(type, member)) ; })
-
 extern int config_debug;
 void debug_msg(const char *fmt, ...);
 void err_msg(const char *fmt, ...);