With the previous patch, there is an extra watchdog read in each retry.
Now the total number of clocksource reads is increased to 4 per iteration.
In order to avoid increasing the clock skew check overhead, the default
maximum number of retries is reduced from 3 to 2 to maintain the same 12
clocksource reads in the worst case.
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
clocksource.max_cswd_read_retries= [KNL]
Number of clocksource_watchdog() retries due to
external delays before the clock will be marked
- unstable. Defaults to three retries, that is,
- four attempts to read the clock under test.
+ unstable. Defaults to two retries, that is,
+ three attempts to read the clock under test.
clocksource.verify_n_cpus= [KNL]
Limit the number of CPUs checked for clocksources
spin_unlock_irqrestore(&watchdog_lock, flags);
}
-ulong max_cswd_read_retries = 3;
+ulong max_cswd_read_retries = 2;
module_param(max_cswd_read_retries, ulong, 0644);
EXPORT_SYMBOL_GPL(max_cswd_read_retries);
static int verify_n_cpus = 8;