tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
perf: net_dropmonitor: Use bisection in symbol lookup
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
authored by
Ben Hutchings
and committed by
David S. Miller
0ce58bae
326017c7
+18
-4
+18
-4
tools/perf/scripts/python/net_dropmonitor.py
+18
-4
tools/perf/scripts/python/net_dropmonitor.py
···
40
40
41
41
def get_sym(sloc):
42
42
loc = int(sloc)
43
-
for symloc, name in kallsyms[::-1]:
44
-
if loc >= symloc:
45
-
return (name, loc - symloc)
46
-
return (None, 0)
43
+
44
+
# Invariant: kallsyms[i][0] <= loc for all 0 <= i <= start
45
+
# kallsyms[i][0] > loc for all end <= i < len(kallsyms)
46
+
start, end = -1, len(kallsyms)
47
+
while end != start + 1:
48
+
pivot = (start + end) // 2
49
+
if loc < kallsyms[pivot][0]:
50
+
end = pivot
51
+
else:
52
+
start = pivot
53
+
54
+
# Now (start == -1 or kallsyms[start][0] <= loc)
55
+
# and (start == len(kallsyms) - 1 or loc < kallsyms[start + 1][0])
56
+
if start >= 0:
57
+
symloc, name = kallsyms[start]
58
+
return (name, loc - symloc)
59
+
else:
60
+
return (None, 0)
47
61
48
62
def print_drop_table():
49
63
print "%25s %25s %25s" % ("LOCATION", "OFFSET", "COUNT")