[RFC PATCH v2 03/15] perf bpf: Save pt_regs info from debuginfo

[He Kuang <hekuang@huawei.com>]

Save reg number in function convert_variable_location() instead of the
register string name, so we can fetch the target register from bpf
context register later.

Signed-off-by: He Kuang <hekuang@huawei.com>
---
 tools/perf/util/include/dwarf-regs.h | 13 +++++++++++++
 tools/perf/util/probe-event.h        |  1 +
 tools/perf/util/probe-finder.c       | 11 +++++++++++
 3 files changed, 25 insertions(+)

diff --git a/tools/perf/util/include/dwarf-regs.h b/tools/perf/util/include/dwarf-regs.h
index 8f14965..566ff6d 100644
--- a/tools/perf/util/include/dwarf-regs.h
+++ b/tools/perf/util/include/dwarf-regs.h
@@ -2,7 +2,20 @@
 #define _PERF_DWARF_REGS_H_
 
 #ifdef HAVE_DWARF_SUPPORT
+struct arch_regs_info {
+	const char      *name;  /* Architecture dependent register string */
+	int             offset; /* Reg offset in struct pt_regs */
+	int             size;   /* Reg size */
+};
+
+#define ARCH_REGS_INFO(r, pt_reg_name)					\
+	{.name	= r,							\
+	.offset = offsetof(struct pt_regs, pt_reg_name),		\
+	.size   = sizeof(((struct pt_regs *)0)->pt_reg_name)}		\
+
 const char *get_arch_regstr(unsigned int n);
+int get_arch_reg_offset(unsigned int n);
+int get_arch_reg_size(unsigned int n);
 #endif
 
 #endif
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index d6b7834..6c19395 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -29,6 +29,7 @@ struct probe_trace_arg {
 	char				*value;	/* Base value */
 	char				*type;	/* Type name */
 	struct probe_trace_arg_ref	*ref;	/* Referencing offset */
+	unsigned int                    regn;   /* Regn from dwarf */
 };
 
 /* kprobe-tracer and uprobe-tracer tracing event (point + arg) */
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index ee27b74..681af00 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -159,6 +159,16 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
 	return ref;
 }
 
+int __attribute__ ((weak))
+get_arch_reg_offset(unsigned int n __maybe_unused) {
+	return -1;
+}
+
+int __attribute__ ((weak))
+get_arch_reg_size(unsigned int n __maybe_unused) {
+	return -1;
+}
+
 /*
  * Convert a location into trace_arg.
  * If tvar == NULL, this just checks variable can be converted.
@@ -260,6 +270,7 @@ static_var:
 		return -ERANGE;
 	}
 
+	tvar->regn = regn;
 	tvar->value = strdup(regs);
 	if (tvar->value == NULL)
 		return -ENOMEM;
-- 
1.8.5.2