make use of BPF.ksym()

diff --git a/tools/vfscount b/tools/vfscount
index 64b5034..70f2f3a 100755 (executable)
--- a/tools/vfscount
+++ b/tools/vfscount
@@ -16,43 +16,6 @@ from ctypes import c_ushort, c_int, c_ulonglong
 from time import sleep, strftime
 from sys import stderr
 
-# kernel symbol translation
-ksym_addrs = []                        # addresses for binary search
-ksym_names = []                        # same index as ksym_addrs
-def load_kallsyms():
-       symfile = "/proc/kallsyms"
-       try:
-               syms = open(symfile, "r")
-       except:
-               print("ERROR: reading " + symfile, file=sys.stderr)
-               exit()
-       line = syms.readline()
-       for line in iter(syms):
-               cols = line.split()
-               name = cols[2]
-               if name[:4] != "vfs_":  # perf optimization
-                       continue
-               addr = int(cols[0], 16)
-               ksym_addrs.append(addr)
-               ksym_names.append(name)
-       syms.close()
-def _ksym_addr2index(addr):
-       start = -1
-       end = len(ksym_addrs)
-       while end != start + 1:
-               mid = int((start + end) / 2)
-               if addr < ksym_addrs[mid]:
-                       end = mid
-               else:
-                       start = mid
-       return start
-def ksym(addr):
-       idx = _ksym_addr2index(addr)
-       if idx == -1:
-               return "[unknown]"
-       return ksym_names[idx]
-load_kallsyms()
-
 # load BPF program
 b = BPF(src_file = "vfscount.c")
 b.attach_kprobe(event_re="^vfs_.*", fn_name="do_count")
@@ -69,4 +32,4 @@ except KeyboardInterrupt:
 print("\n%-16s %-26s %8s" % ("ADDR", "FUNC", "COUNT"))
 counts = b.get_table("counts")
 for k, v in sorted(counts.items(), key=lambda counts: counts[1].value):
-       print("%-16x %-26s %8d" % (k.ip, ksym(k.ip), v.value))
+       print("%-16x %-26s %8d" % (k.ip, b.ksym(k.ip), v.value))