lkml.org 
[lkml]   [2016]   [Nov]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v3 04/33] radix tree test suite: Track preempt_count
    Date
    From: Matthew Wilcox <willy@infradead.org>

    Rather than simply NOP out preempt_enable() and preempt_disable(),
    keep track of preempt_count and display it regularly in case either
    the test suite or the code under test is forgetting to balance the
    enables & disables. Only found a test-case that was forgetting to
    re-enable preemption, but it's a possibility worth checking.

    Signed-off-by: Matthew Wilcox <willy@infradead.org>
    ---
    tools/testing/radix-tree/linux.c | 1 +
    tools/testing/radix-tree/linux/preempt.h | 6 +++---
    tools/testing/radix-tree/main.c | 30 ++++++++++++++++++++----------
    3 files changed, 24 insertions(+), 13 deletions(-)

    diff --git a/tools/testing/radix-tree/linux.c b/tools/testing/radix-tree/linux.c
    index 3cfb04e..1f32a16 100644
    --- a/tools/testing/radix-tree/linux.c
    +++ b/tools/testing/radix-tree/linux.c
    @@ -9,6 +9,7 @@
    #include <urcu/uatomic.h>

    int nr_allocated;
    +int preempt_count;

    void *mempool_alloc(mempool_t *pool, int gfp_mask)
    {
    diff --git a/tools/testing/radix-tree/linux/preempt.h b/tools/testing/radix-tree/linux/preempt.h
    index 6210672..65c04c2 100644
    --- a/tools/testing/radix-tree/linux/preempt.h
    +++ b/tools/testing/radix-tree/linux/preempt.h
    @@ -1,4 +1,4 @@
    -/* */
    +extern int preempt_count;

    -#define preempt_disable() do { } while (0)
    -#define preempt_enable() do { } while (0)
    +#define preempt_disable() uatomic_inc(&preempt_count)
    +#define preempt_enable() uatomic_dec(&preempt_count)
    diff --git a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
    index daa9010..64ffe67 100644
    --- a/tools/testing/radix-tree/main.c
    +++ b/tools/testing/radix-tree/main.c
    @@ -293,27 +293,36 @@ static void single_thread_tests(bool long_run)
    {
    int i;

    - printf("starting single_thread_tests: %d allocated\n", nr_allocated);
    + printf("starting single_thread_tests: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    multiorder_checks();
    - printf("after multiorder_check: %d allocated\n", nr_allocated);
    + printf("after multiorder_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    locate_check();
    - printf("after locate_check: %d allocated\n", nr_allocated);
    + printf("after locate_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    tag_check();
    - printf("after tag_check: %d allocated\n", nr_allocated);
    + printf("after tag_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    gang_check();
    - printf("after gang_check: %d allocated\n", nr_allocated);
    + printf("after gang_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    add_and_check();
    - printf("after add_and_check: %d allocated\n", nr_allocated);
    + printf("after add_and_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    dynamic_height_check();
    - printf("after dynamic_height_check: %d allocated\n", nr_allocated);
    + printf("after dynamic_height_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    big_gang_check(long_run);
    - printf("after big_gang_check: %d allocated\n", nr_allocated);
    + printf("after big_gang_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    for (i = 0; i < (long_run ? 2000 : 3); i++) {
    copy_tag_check();
    printf("%d ", i);
    fflush(stdout);
    }
    - printf("after copy_tag_check: %d allocated\n", nr_allocated);
    + printf("after copy_tag_check: %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    }

    int main(int argc, char **argv)
    @@ -336,7 +345,8 @@ int main(int argc, char **argv)
    single_thread_tests(long_run);

    sleep(1);
    - printf("after sleep(1): %d allocated\n", nr_allocated);
    + printf("after sleep(1): %d allocated, preempt %d\n",
    + nr_allocated, preempt_count);
    rcu_unregister_thread();

    exit(0);
    --
    2.10.2
    \
     
     \ /
      Last update: 2016-11-28 21:07    [W:7.686 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site