[PATCH 3/4] leaking_addresses: cache architecture name

From: Tobin C. Harding
Date: Sun Feb 18 2018 - 21:51:27 EST


Currently we are repeatedly calling `uname -m`. This is causing the
script to take a long time to run (more than 10 seconds to parse
/proc/kallsyms). We can use Perl state variables to cache the result of
the first call to `uname -m`. With this change in place the script
scans the whole kernel in under a minute.

Cache machine architecture in state variable.

Signed-off-by: Tobin C. Harding <me@xxxxxxxx>
---
scripts/leaking_addresses.pl | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/scripts/leaking_addresses.pl b/scripts/leaking_addresses.pl
index e7bf15a45a69..f52e91ef7d5c 100755
--- a/scripts/leaking_addresses.pl
+++ b/scripts/leaking_addresses.pl
@@ -175,7 +175,7 @@ sub is_32bit

sub is_ix86_32
{
- my $arch = `uname -m`;
+ state $arch = `uname -m`;

chomp $arch;
if ($arch =~ m/i[3456]86/) {
@@ -198,12 +198,14 @@ sub is_arch

sub is_x86_64
{
- return is_arch('x86_64');
+ state $is = is_arch('x86_64');
+ return $is;
}

sub is_ppc64
{
- return is_arch('ppc64');
+ state $is = is_arch('ppc64');
+ return $is;
}

# Gets config option value from kernel config file.
--
2.7.4