git.openwrt.org Git - openwrt/staging/neocturne.git/blob

   1 From 0f354629c10f457751c20a230b13b1b7ac2f1fbc Mon Sep 17 00:00:00 2001
   2 From: David Gow <davidgow@google.com>
   3 Date: Fri, 25 Nov 2022 16:43:04 +0800
   4 Subject: [PATCH] kunit: Provide a static key to check if KUnit is
   5  actively running tests
   6
   7 KUnit does a few expensive things when enabled. This hasn't been a
   8 problem because KUnit was only enabled on test kernels, but with a few
   9 people enabling (but not _using_) KUnit on production systems, we need a
  10 runtime way of handling this.
  11
  12 Provide a 'kunit_running' static key (defaulting to false), which allows
  13 us to hide any KUnit code behind a static branch. This should reduce the
  14 performance impact (on other code) of having KUnit enabled to a single
  15 NOP when no tests are running.
  16
  17 Note that, while it looks unintuitive, tests always run entirely within
  18 __kunit_test_suites_init(), so it's safe to decrement the static key at
  19 the end of this function, rather than in __kunit_test_suites_exit(),
  20 which is only there to clean up results in debugfs.
  21
  22 Signed-off-by: David Gow <davidgow@google.com>
  23 Reviewed-by: Daniel Latypov <dlatypov@google.com>
  24 Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
  25 ---
  26  include/kunit/test.h | 4 ++++
  27  lib/kunit/test.c     | 6 ++++++
  28  2 files changed, 10 insertions(+)
  29
  30 --- a/include/kunit/test.h
  31 +++ b/include/kunit/test.h
  32 @@ -16,6 +16,7 @@
  33  #include <linux/container_of.h>
  34  #include <linux/err.h>
  35  #include <linux/init.h>
  36 +#include <linux/jump_label.h>
  37  #include <linux/kconfig.h>
  38  #include <linux/kref.h>
  39  #include <linux/list.h>
  40 @@ -27,6 +28,9 @@
  41
  42  #include <asm/rwonce.h>
  43
  44 +/* Static key: true if any KUnit tests are currently running */
  45 +DECLARE_STATIC_KEY_FALSE(kunit_running);
  46 +
  47  struct kunit;
  48
  49  /* Size of log associated with test. */
  50 --- a/lib/kunit/test.c
  51 +++ b/lib/kunit/test.c
  52 @@ -20,6 +20,8 @@
  53  #include "string-stream.h"
  54  #include "try-catch-impl.h"
  55
  56 +DEFINE_STATIC_KEY_FALSE(kunit_running);
  57 +
  58  #if IS_BUILTIN(CONFIG_KUNIT)
  59  /*
  60   * Fail the current test and print an error message to the log.
  61 @@ -622,10 +624,14 @@ int __kunit_test_suites_init(struct kuni
  62                 return 0;
  63         }
  64
  65 +       static_branch_inc(&kunit_running);
  66 +
  67         for (i = 0; i < num_suites; i++) {
  68                 kunit_init_suite(suites[i]);
  69                 kunit_run_tests(suites[i]);
  70         }
  71 +
  72 +       static_branch_dec(&kunit_running);
  73         return 0;
  74  }
  75  EXPORT_SYMBOL_GPL(__kunit_test_suites_init);