clocksource: Limit number of CPUs checked for clock synchronization

[linux-2.6-microblaze.git] / Documentation / admin-guide / kernel-parameters.txt

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 995decc..9ec9ea1 100644 (file)
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -587,6 +587,16 @@
                        unstable.  Defaults to three retries, that is,
                        four attempts to read the clock under test.
 
+       clocksource.verify_n_cpus= [KNL]
+                       Limit the number of CPUs checked for clocksources
+                       marked with CLOCK_SOURCE_VERIFY_PERCPU that
+                       are marked unstable due to excessive skew.
+                       A negative value says to check all CPUs, while
+                       zero says not to check any.  Values larger than
+                       nr_cpu_ids are silently truncated to nr_cpu_ids.
+                       The actual CPUs are chosen randomly, with
+                       no replacement if the same CPU is chosen twice.
+
        clearcpuid=BITNUM[,BITNUM...] [X86]
                        Disable CPUID feature X for the kernel. See
                        arch/x86/include/asm/cpufeatures.h for the valid bit