ftrace/samples: add s390 support for ftrace direct multi sample
Add s390 architecture support for the ftrace direct multi sample.
See commit 5fae941b9a6f ("ftrace/samples: Add multi direct interface
test module") for further details.
Link: https://lore.kernel.org/r/20211115195614.3173346-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 35f99b8..2a5bb4f 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -194,6 +194,7 @@
select HAVE_RELIABLE_STACKTRACE
select HAVE_RSEQ
select HAVE_SAMPLE_FTRACE_DIRECT
+ select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
select HAVE_SOFTIRQ_ON_OWN_STACK
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_VIRT_CPU_ACCOUNTING
diff --git a/samples/ftrace/ftrace-direct-multi.c b/samples/ftrace/ftrace-direct-multi.c
index b6d7806..2fafc9a 100644
--- a/samples/ftrace/ftrace-direct-multi.c
+++ b/samples/ftrace/ftrace-direct-multi.c
@@ -4,6 +4,7 @@
#include <linux/mm.h> /* for handle_mm_fault() */
#include <linux/ftrace.h>
#include <linux/sched/stat.h>
+#include <asm/asm-offsets.h>
extern void my_direct_func(unsigned long ip);
@@ -14,6 +15,8 @@ void my_direct_func(unsigned long ip)
extern void my_tramp(void *);
+#ifdef CONFIG_X86_64
+
asm (
" .pushsection .text, \"ax\", @progbits\n"
" .type my_tramp, @function\n"
@@ -31,6 +34,33 @@ asm (
" .popsection\n"
);
+#endif /* CONFIG_X86_64 */
+
+#ifdef CONFIG_S390
+
+asm (
+" .pushsection .text, \"ax\", @progbits\n"
+" .type my_tramp, @function\n"
+" .globl my_tramp\n"
+" my_tramp:"
+" lgr %r1,%r15\n"
+" stmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
+" stg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
+" aghi %r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n"
+" stg %r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n"
+" lgr %r2,%r0\n"
+" brasl %r14,my_direct_func\n"
+" aghi %r15,"__stringify(STACK_FRAME_OVERHEAD)"\n"
+" lmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
+" lg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
+" lgr %r1,%r0\n"
+" br %r1\n"
+" .size my_tramp, .-my_tramp\n"
+" .popsection\n"
+);
+
+#endif /* CONFIG_S390 */
+
static struct ftrace_ops direct;
static int __init ftrace_direct_multi_init(void)
