Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core

5 files changed, 78 insertions, 11 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index c80235206c01..2590ce20157d 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -87,6 +87,7 @@ config S390
         select HAVE_SYSCALL_TRACEPOINTS
         select HAVE_DYNAMIC_FTRACE
         select HAVE_FUNCTION_GRAPH_TRACER
+        select HAVE_REGS_AND_STACK_ACCESS_API
         select HAVE_DEFAULT_NO_SPIN_MUTEXES
         select HAVE_OPROFILE
         select HAVE_KPROBES
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 95dcf183a28d..dd2d913afcae 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -492,13 +492,24 @@ struct user_regs_struct
 struct task_struct;
 extern void user_enable_single_step(struct task_struct *);
 extern void user_disable_single_step(struct task_struct *);
+extern void show_regs(struct pt_regs * regs);
 
 #define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0)
 #define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN)
 #define user_stack_pointer(regs)((regs)->gprs[15])
 #define regs_return_value(regs)((regs)->gprs[2])
 #define profile_pc(regs) instruction_pointer(regs)
-extern void show_regs(struct pt_regs * regs);
+
+int regs_query_register_offset(const char *name);
+const char *regs_query_register_name(unsigned int offset);
+unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset);
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n);
+
+static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
+{
+        return regs->gprs[15] & PSW_ADDR_INSN;
+}
+
 #endif /* __KERNEL__ */
 #endif /* __ASSEMBLY__ */
 
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index e0a73d3eb837..8429686951f9 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -15,6 +15,13 @@
 #include <linux/sched.h>
 #include <asm/ptrace.h>
 
+/*
+ * The syscall table always contains 32 bit pointers since we know that the
+ * address of the function to be called is (way) below 4GB.  So the "int"
+ * type here is what we want [need] for both 32 bit and 64 bit systems.
+ */
+extern const unsigned int sys_call_table[];
+
 static inline long syscall_get_nr(struct task_struct *task,
                                   struct pt_regs *regs)
 {
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 5a82bc68193e..9e69449e77ad 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -200,13 +200,3 @@ out:
         return parent;
 }
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned int sys_call_table[];
-
-unsigned long __init arch_syscall_addr(int nr)
-{
-        return (unsigned long)sys_call_table[nr];
-}
-#endif
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 7cf464234419..33fdc5a79764 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -992,3 +992,61 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 #endif
         return &user_s390_view;
 }
+
+static const char *gpr_names[NUM_GPRS] = {
+        "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
+        "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
+};
+
+unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
+{
+        if (offset >= NUM_GPRS)
+                return 0;
+        return regs->gprs[offset];
+}
+
+int regs_query_register_offset(const char *name)
+{
+        unsigned long offset;
+
+        if (!name || *name != 'r')
+                return -EINVAL;
+        if (strict_strtoul(name + 1, 10, &offset))
+                return -EINVAL;
+        if (offset >= NUM_GPRS)
+                return -EINVAL;
+        return offset;
+}
+
+const char *regs_query_register_name(unsigned int offset)
+{
+        if (offset >= NUM_GPRS)
+                return NULL;
+        return gpr_names[offset];
+}
+
+static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+        unsigned long ksp = kernel_stack_pointer(regs);
+
+        return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
+}
+
+/**
+ * regs_get_kernel_stack_nth() - get Nth entry of the stack
+ * @regs:pt_regs which contains kernel stack pointer.
+ * @n:stack entry number.
+ *
+ * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
+ * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
+ * this returns 0.
+ */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+        unsigned long addr;
+
+        addr = kernel_stack_pointer(regs) + n * sizeof(long);
+        if (!regs_within_kernel_stack(regs, addr))
+                return 0;
+        return *(unsigned long *)addr;
+}