From: Rafael J. Wysocki Measure the time of the freezing of tasks, even if it doesn't fail. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton --- kernel/power/process.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff -puN kernel/power/process.c~freezer-measure-freezing-time kernel/power/process.c --- a/kernel/power/process.c~freezer-measure-freezing-time +++ a/kernel/power/process.c @@ -183,6 +183,11 @@ static int try_to_freeze_tasks(int freez struct task_struct *g, *p; unsigned long end_time; unsigned int todo; + struct timeval start, end; + s64 elapsed_csecs64; + unsigned int elapsed_csecs; + + do_gettimeofday(&start); end_time = jiffies + TIMEOUT; do { @@ -218,6 +223,11 @@ static int try_to_freeze_tasks(int freez break; } while (todo); + do_gettimeofday(&end); + elapsed_csecs64 = timeval_to_ns(&end) - timeval_to_ns(&start); + do_div(elapsed_csecs64, NSEC_PER_SEC / 100); + elapsed_csecs = elapsed_csecs64; + if (todo) { /* This does not unfreeze processes that are already frozen * (we have slightly ugly calling convention in that respect, @@ -225,10 +235,9 @@ static int try_to_freeze_tasks(int freez * but it cleans up leftover PF_FREEZE requests. */ printk("\n"); - printk(KERN_ERR "Freezing of %s timed out after %d seconds " + printk(KERN_ERR "Freezing of tasks failed after %d.%02d seconds " "(%d tasks refusing to freeze):\n", - freeze_user_space ? "user space " : "tasks ", - TIMEOUT / HZ, todo); + elapsed_csecs / 100, elapsed_csecs % 100, todo); show_state(); read_lock(&tasklist_lock); do_each_thread(g, p) { @@ -239,6 +248,9 @@ static int try_to_freeze_tasks(int freez task_unlock(p); } while_each_thread(g, p); read_unlock(&tasklist_lock); + } else { + printk("(elapsed %d.%02d seconds) ", elapsed_csecs / 100, + elapsed_csecs % 100); } return todo ? -EBUSY : 0; _