From: "Paul E. McKenney" paulmck@kernel.org
This commit adds a get_torture_init_jiffies() function that returns the value of the jiffies counter at the start of the test, that is, at the point where torture_init_begin() was invoked.
This will be used to enable torture-test holdoffs for tests implemented using per-CPU kthreads, which are created and deleted by CPU-hotplug operations, and thus (unlike normal kthreads) don't automatically know when the test started.
Signed-off-by: Paul E. McKenney paulmck@kernel.org Signed-off-by: Boqun Feng boqun.feng@gmail.com --- include/linux/torture.h | 1 + kernel/torture.c | 12 ++++++++++++ 2 files changed, 13 insertions(+)
diff --git a/include/linux/torture.h b/include/linux/torture.h index 0134e7221cae..1b59056c3b18 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -104,6 +104,7 @@ int torture_stutter_init(int s, int sgap); /* Initialization and cleanup. */ bool torture_init_begin(char *ttype, int v); void torture_init_end(void); +unsigned long get_torture_init_jiffies(void); bool torture_cleanup_begin(void); void torture_cleanup_end(void); bool torture_must_stop(void); diff --git a/kernel/torture.c b/kernel/torture.c index dede150aef01..3a0a8cc60401 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -792,6 +792,8 @@ static void torture_stutter_cleanup(void) stutter_task = NULL; }
+static unsigned long torture_init_jiffies; + static void torture_print_module_parms(void) { @@ -821,6 +823,7 @@ bool torture_init_begin(char *ttype, int v) torture_type = ttype; verbose = v; fullstop = FULLSTOP_DONTSTOP; + WRITE_ONCE(torture_init_jiffies, jiffies); // Lockless reads. torture_print_module_parms(); return true; } @@ -836,6 +839,15 @@ void torture_init_end(void) } EXPORT_SYMBOL_GPL(torture_init_end);
+/* + * Get the torture_init_begin()-time value of the jiffies counter. + */ +unsigned long get_torture_init_jiffies(void) +{ + return READ_ONCE(torture_init_jiffies); +} +EXPORT_SYMBOL_GPL(get_torture_init_jiffies); + /* * Clean up torture module. Please note that this is -not- invoked via * the usual module_exit() mechanism, but rather by an explicit call from