[PATCH 2/2] um/ptrace: Implement HAVE_SYSCALL_TRACEPOINTS

[Thomas Weißschuh]

Implement syscall tracepoints through the generic tracing infrastructure.

Signed-off-by: Thomas Weißschuh <thomas.weisssc...@linutronix.de>
Reviewed-by: Nam Cao <nam...@linutronix.de>
---
 arch/um/Kconfig                   | 1 +
 arch/um/include/asm/thread_info.h | 2 ++
 arch/um/kernel/ptrace.c           | 9 +++++++++
 3 files changed, 12 insertions(+)

diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 
f08e8a7fac93d9f98384de02710542fd75d23553..c2d2d2d99bbe3f5a5dc4afaa69e02a520e326c2d
 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -35,6 +35,7 @@ config UML
        select HAVE_RUST
        select ARCH_HAS_UBSAN
        select HAVE_ARCH_TRACEHOOK
+       select HAVE_SYSCALL_TRACEPOINTS
        select THREAD_INFO_IN_TASK
 
 config MMU
diff --git a/arch/um/include/asm/thread_info.h 
b/arch/um/include/asm/thread_info.h
index 
f9ad06fcc991a2b10e2aa6059880b993e3d60a2d..b8c021f97bd17515e4f9082206addfce05b9321e
 100644
--- a/arch/um/include/asm/thread_info.h
+++ b/arch/um/include/asm/thread_info.h
@@ -43,6 +43,8 @@ struct thread_info {
 #define TIF_NOTIFY_RESUME      8
 #define TIF_SECCOMP            9       /* secure computing */
 #define TIF_SINGLESTEP         10      /* single stepping userspace */
+#define TIF_SYSCALL_TRACEPOINT 11      /* syscall tracepoint instrumentation */
+
 
 #define _TIF_SYSCALL_TRACE     (1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING                (1 << TIF_SIGPENDING)
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index 
2124624b7817439b8e1c962e8e6eb0e267db6f53..fdbb37b5c3996188d92cf307d31eeaeca1f0acce
 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -9,6 +9,9 @@
 #include <linux/uaccess.h>
 #include <asm/ptrace-abi.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
 void user_enable_single_step(struct task_struct *child)
 {
        set_tsk_thread_flag(child, TIF_SINGLESTEP);
@@ -126,6 +129,9 @@ int syscall_trace_enter(struct pt_regs *regs)
                            UPT_SYSCALL_ARG3(&regs->regs),
                            UPT_SYSCALL_ARG4(&regs->regs));
 
+       if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+               trace_sys_enter(regs, UPT_SYSCALL_NR(&regs->regs));
+
        if (!test_thread_flag(TIF_SYSCALL_TRACE))
                return 0;
 
@@ -142,6 +148,9 @@ void syscall_trace_leave(struct pt_regs *regs)
        if (test_thread_flag(TIF_SINGLESTEP))
                send_sigtrap(&regs->regs, 0);
 
+       if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+               trace_sys_exit(regs, PT_REGS_SYSCALL_RET(regs));
+
        if (!test_thread_flag(TIF_SYSCALL_TRACE))
                return;
 

-- 
2.50.0