2 files changed, 26 insertions, 8 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index f0e7ccf1b206..92a4f7b4323a 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -16,6 +16,9 @@ config LOCKDEP_SUPPORT
 config STACKTRACE_SUPPORT
         def_bool y
 
+config HAVE_LATENCYTOP_SUPPORT
+        def_bool y
+
 config RWSEM_GENERIC_SPINLOCK
         bool
 
diff --git a/arch/s390/kernel/stacktrace.c b/arch/s390/kernel/stacktrace.c
index da6924729964..85e46a5d0e08 100644
--- a/arch/s390/kernel/stacktrace.c
+++ b/arch/s390/kernel/stacktrace.c
@@ -14,7 +14,8 @@
 static unsigned long save_context_stack(struct stack_trace *trace,
                                         unsigned long sp,
                                         unsigned long low,
-                                        unsigned long high)
+                                        unsigned long high,
+                                        int savesched)
 {
         struct stack_frame *sf;
         struct pt_regs *regs;
@@ -47,10 +48,12 @@ static unsigned long save_context_stack(struct stack_trace *trace,
                         return sp;
                 regs = (struct pt_regs *)sp;
                 addr = regs->psw.addr & PSW_ADDR_INSN;
-                if (!trace->skip)
-                        trace->entries[trace->nr_entries++] = addr;
-                else
-                        trace->skip--;
+                if (savesched || !in_sched_functions(addr)) {
+                        if (!trace->skip)
+                                trace->entries[trace->nr_entries++] = addr;
+                        else
+                                trace->skip--;
+                }
                 if (trace->nr_entries >= trace->max_entries)
                         return sp;
                 low = sp;
@@ -66,15 +69,27 @@ void save_stack_trace(struct stack_trace *trace)
         orig_sp = sp & PSW_ADDR_INSN;
         new_sp = save_context_stack(trace, orig_sp,
                                     S390_lowcore.panic_stack - PAGE_SIZE,
-                                    S390_lowcore.panic_stack);
+                                    S390_lowcore.panic_stack, 1);
         if (new_sp != orig_sp)
                 return;
         new_sp = save_context_stack(trace, new_sp,
                                     S390_lowcore.async_stack - ASYNC_SIZE,
-                                    S390_lowcore.async_stack);
+                                    S390_lowcore.async_stack, 1);
         if (new_sp != orig_sp)
                 return;
         save_context_stack(trace, new_sp,
                            S390_lowcore.thread_info,
-                           S390_lowcore.thread_info + THREAD_SIZE);
+                           S390_lowcore.thread_info + THREAD_SIZE, 1);
+}
+
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+        unsigned long sp, low, high;
+
+        sp = tsk->thread.ksp & PSW_ADDR_INSN;
+        low = (unsigned long) task_stack_page(tsk);
+        high = (unsigned long) task_pt_regs(tsk);
+        save_context_stack(trace, sp, low, high, 0);
+        if (trace->nr_entries < trace->max_entries)
+                trace->entries[trace->nr_entries++] = ULONG_MAX;
 }