[PATCH 1/3] rtla: Add libsubcmd dependency
From: Tomas Glozar
Date: Fri Mar 20 2026 - 11:12:57 EST
In preparation to 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 function and macros shipped with the kernel to be
used in RTLA; perf and bpftool, two other users of libsubcmd, already do
that.
To prevent 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
Signed-off-by: Tomas Glozar <tglozar@xxxxxxxxxx>
---
tools/tracing/rtla/.gitignore | 1 +
tools/tracing/rtla/Makefile | 53 +++++++++++++++++++++++++++++-----
tools/tracing/rtla/src/rtla.c | 8 ++---
tools/tracing/rtla/src/utils.h | 6 ++--
4 files changed, 53 insertions(+), 15 deletions(-)
diff --git a/tools/tracing/rtla/.gitignore b/tools/tracing/rtla/.gitignore
index 4d39d64ac08c..123c2d5ed7ac 100644
--- a/tools/tracing/rtla/.gitignore
+++ b/tools/tracing/rtla/.gitignore
@@ -9,3 +9,4 @@ custom_filename.txt
osnoise_irq_noise_hist.txt
osnoise_trace.txt
timerlat_trace.txt
+libsubcmd/
diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile
index 45690ee14544..289e44c9664b 100644
--- a/tools/tracing/rtla/Makefile
+++ b/tools/tracing/rtla/Makefile
@@ -27,6 +27,24 @@ 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 = $(LIBSUBCMD_OUTPUT)/libsubcmd.a
+LIBSUBCMD_INCLUDES = -I$(LIBSUBCMD_OUTPUT)/include
+LIBSUBCMD_MAKEFLAGS = O=$(LIBSUBCMD_OUTPUT) DESTDIR=$(LIBSUBCMD_OUTPUT) prefix= subdir=
+
+TOOLS_INCLUDES = -I$(srctree)/tools/include
+
+LIB_STRING = $(OUTPUT)string.o
+LIB_STRING_SRC = $(srctree)/tools/lib/string.c
+
+LIB_STR_ERROR_R = $(OUTPUT)str_error_r.o
+LIB_STR_ERROR_R_SRC = $(srctree)/tools/lib/str_error_r.c
+
VERSION := $(shell sh -c "make -sC ../../.. kernelversion | grep -v make")
DOCSRC := ../../../Documentation/tools/rtla/
@@ -66,7 +84,7 @@ ifeq ($(config),1)
include Makefile.config
endif
-CFLAGS += $(INCLUDES) $(LIB_INCLUDES)
+CFLAGS += $(INCLUDES) $(LIB_INCLUDES) $(TOOLS_INCLUDES) $(LIBSUBCMD_INCLUDES)
export CFLAGS OUTPUT srctree
@@ -93,20 +111,41 @@ 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): $(LIBSUBCMD_OUTPUT)
+ $(Q)$(MAKE) -C $(LIBSUBCMD_DIR) $(LIBSUBCMD_MAKEFLAGS) \
+ install_headers
+
+$(LIBSUBCMD): fixdep $(LIBSUBCMD_OUTPUT)
+ $(Q)$(MAKE) -C $(LIBSUBCMD_DIR) $(LIBSUBCMD_MAKEFLAGS) \
+ $@
+
+$(LIB_STR_ERROR_R): $(LIB_STR_ERROR_R_SRC)
+ $(QUIET_CC)$(CC) $(CFLAGS) -c -o $@ $<
+
+$(LIB_STRING): $(LIB_STRING_SRC)
+ $(QUIET_CC)$(CC) $(CFLAGS) -c -o $@ $<
+
+$(LIBSUBCMD)-clean:
+ $(call QUIET_CLEAN, libsubcmd)
+ $(Q)$(RM) -r -- $(LIBSUBCMD_OUTPUT)
+
+clean: doc_clean fixdep-clean $(LIBSUBCMD)-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 7635c70123ab..845932f902ef 100644
--- 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]);
@@ -66,7 +66,7 @@ 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);
@@ -79,7 +79,7 @@ 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 e794ede64b2c..96fd72042717 100644
--- 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, ...);
--
2.53.0