[RFC PATCH 3/6] perf bpf: Save pt_regs info from debuginfo

[He Kuang <hekuang@huawei.com>]

Save pt_regs number and size information 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 |  2 ++
 tools/perf/util/probe-event.h        |  4 ++++
 tools/perf/util/probe-finder.c       | 11 +++++++++++
 3 files changed, 17 insertions(+)

diff --git a/tools/perf/util/include/dwarf-regs.h b/tools/perf/util/include/dwarf-regs.h
index 8f14965..166bec2 100644
--- a/tools/perf/util/include/dwarf-regs.h
+++ b/tools/perf/util/include/dwarf-regs.h
@@ -3,6 +3,8 @@
 
 #ifdef HAVE_DWARF_SUPPORT
 const char *get_arch_regstr(unsigned int n);
+char get_arch_pt_regs(unsigned int n);
+int get_arch_pt_regs_size(void);
 #endif
 
 #endif
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index d6b7834..842d6c4 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -29,6 +29,10 @@ struct probe_trace_arg {
 	char				*value;	/* Base value */
 	char				*type;	/* Type name */
 	struct probe_trace_arg_ref	*ref;	/* Referencing offset */
+	unsigned int regn;
+	unsigned int reg_size;
+	char *insns;
+	int insns_cnt;
 };
 
 /* 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 2a76e14..249e6cb 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -159,6 +159,15 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
 	return ref;
 }
 
+char __attribute__ ((weak)) get_arch_pt_regs(unsigned int n) {
+	n = n;
+	return -1;
+}
+
+int __attribute__ ((weak)) get_arch_pt_regs_size(void) {
+	return -1;
+}
+
 /*
  * Convert a location into trace_arg.
  * If tvar == NULL, this just checks variable can be converted.
@@ -260,6 +269,8 @@ static_var:
 		return -ERANGE;
 	}
 
+	tvar->regn = get_arch_pt_regs(regn);
+	tvar->reg_size = get_arch_pt_regs_size();
 	tvar->value = strdup(regs);
 	if (tvar->value == NULL)
 		return -ENOMEM;
-- 
1.8.5.2