Merge branch 'master' into pr6866

Conflicts:
	ChangeLog: Removed
	runtime/ChangeLog: Removed
	runtime/sym.c: Merged
	runtime/task_finder.c: Merged
	tapset/ChangeLog: Removed
	testsuite/ChangeLog: Removed

1 files changed, 93 insertions, 3 deletions

diff --git a/runtime/stack.c b/runtime/stack.c
index 23ac2edc..aa0e6d65 100644
--- a/runtime/stack.c
+++ b/runtime/stack.c
@@ -27,6 +27,14 @@
 
 #define MAXBACKTRACE 20
 
+#if defined(CONFIG_STACKTRACE) && LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
+// XXX: PR9866: hacky temporarily restriction to recent kernels
+#include <linux/stacktrace.h>
+#include <asm/stacktrace.h>
+#endif
+
+static void _stp_stack_print_fallback(unsigned long, int, int);
+
 #if defined (__x86_64__)
 #include "stack-x86_64.c"
 #elif defined (__ia64__)
@@ -43,11 +51,58 @@
 #error "Unsupported architecture"
 #endif
 
+#if defined(CONFIG_STACKTRACE) && LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
+
+struct print_stack_data
+{
+        int verbose;
+        int max_level;
+        int level;
+};
+
+static void print_stack_warning(void *data, char *msg)
+{
+}
+
+static void
+print_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
+{
+}
+
+static int print_stack_stack(void *data, char *name)
+{
+	return -1;
+}
+
+static void print_stack_address(void *data, unsigned long addr, int reliable)
+{
+	struct print_stack_data *sdata = data;
+        if (sdata->level++ < sdata->max_level)
+                _stp_func_print(addr,sdata->verbose, 0);
+}
+
+static const struct stacktrace_ops print_stack_ops = {
+	.warning = print_stack_warning,
+	.warning_symbol = print_stack_warning_symbol,
+	.stack = print_stack_stack,
+	.address = print_stack_address,
+};
+
+static void _stp_stack_print_fallback(unsigned long stack, int verbose, int levels)
+{
+        struct print_stack_data print_data;
+        print_data.verbose = verbose;
+        print_data.max_level = levels;
+        print_data.level = 0;
+        dump_trace(current, NULL, (long *)stack, 0, &print_stack_ops,
+                   &print_data);
+}
+#endif
 /** Prints the stack backtrace
  * @param regs A pointer to the struct pt_regs.
  */
 
-void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
+static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
 {
 	if (verbose) {
 		/* print the current address */
@@ -75,7 +130,7 @@ void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe_instan
  * @param regs A pointer to the struct pt_regs.
  * @returns void
  */
-void _stp_stack_snprint(char *str, int size, struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
+static void _stp_stack_snprint(char *str, int size, struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
 {
 	/* To get a string, we use a simple trick. First flush the print buffer, */
 	/* then call _stp_stack_print, then copy the result into the output string  */
@@ -93,7 +148,7 @@ void _stp_stack_snprint(char *str, int size, struct pt_regs *regs, int verbose,
  * @note Currently limited to a depth of two. Works from jprobes and kprobes.
  */
 #if 0
-void _stp_ustack_print(char *str)
+static void _stp_ustack_print(char *str)
 {
 	struct pt_regs *nregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long)current->thread_info)) - 1;
 	_stp_printf("%p : [user]\n", (int64_t) REG_IP(nregs));
@@ -103,4 +158,39 @@ void _stp_ustack_print(char *str)
 #endif /* 0 */
 
 /** @} */
+
+void _stp_stack_print_tsk(struct task_struct *tsk, int verbose, int levels)
+{
+#if defined(CONFIG_STACKTRACE) && LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
+        int i;
+        unsigned long backtrace[MAXBACKTRACE];
+        struct stack_trace trace;
+        int maxLevels = min(levels, MAXBACKTRACE);
+        memset(&trace, 0, sizeof(trace));
+        trace.entries = &backtrace[0];
+        trace.max_entries = maxLevels;
+        trace.skip = 0;
+        save_stack_trace_tsk(tsk, &trace);
+        for (i = 0; i < maxLevels; ++i) {
+                if (backtrace[i] == 0 || backtrace[i] == ULONG_MAX)
+                        break;
+                _stp_printf("%lx ", backtrace[i]);
+        }
+#endif
+}
+
+/** Writes a task stack backtrace to a string
+ *
+ * @param str string
+ * @param tsk A pointer to the task_struct
+ * @returns void
+ */
+void _stp_stack_snprint_tsk(char *str, int size, struct task_struct *tsk, int verbose, int levels)
+{
+	_stp_pbuf *pb = per_cpu_ptr(Stp_pbuf, smp_processor_id());
+	_stp_print_flush();
+	_stp_stack_print_tsk(tsk, verbose, levels);
+	strlcpy(str, pb->buf, size < (int)pb->len ? size : (int)pb->len);
+	pb->len = 0;
+}
 #endif /* _STACK_C_ */