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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/x86/kernel/tsc_sync.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/x86/kernel/tsc_sync.c')
-rw-r--r--kernel/arch/x86/kernel/tsc_sync.c16
1 files changed, 7 insertions, 9 deletions
diff --git a/kernel/arch/x86/kernel/tsc_sync.c b/kernel/arch/x86/kernel/tsc_sync.c
index 26488487b..78083bf23 100644
--- a/kernel/arch/x86/kernel/tsc_sync.c
+++ b/kernel/arch/x86/kernel/tsc_sync.c
@@ -39,16 +39,15 @@ static cycles_t max_warp;
static int nr_warps;
/*
- * TSC-warp measurement loop running on both CPUs:
+ * TSC-warp measurement loop running on both CPUs. This is not called
+ * if there is no TSC.
*/
static void check_tsc_warp(unsigned int timeout)
{
cycles_t start, now, prev, end;
int i;
- rdtsc_barrier();
- start = get_cycles();
- rdtsc_barrier();
+ start = rdtsc_ordered();
/*
* The measurement runs for 'timeout' msecs:
*/
@@ -63,9 +62,7 @@ static void check_tsc_warp(unsigned int timeout)
*/
arch_spin_lock(&sync_lock);
prev = last_tsc;
- rdtsc_barrier();
- now = get_cycles();
- rdtsc_barrier();
+ now = rdtsc_ordered();
last_tsc = now;
arch_spin_unlock(&sync_lock);
@@ -113,7 +110,7 @@ static void check_tsc_warp(unsigned int timeout)
*/
static inline unsigned int loop_timeout(int cpu)
{
- return (cpumask_weight(cpu_core_mask(cpu)) > 1) ? 2 : 20;
+ return (cpumask_weight(topology_core_cpumask(cpu)) > 1) ? 2 : 20;
}
/*
@@ -126,7 +123,7 @@ void check_tsc_sync_source(int cpu)
/*
* No need to check if we already know that the TSC is not
- * synchronized:
+ * synchronized or if we have no TSC.
*/
if (unsynchronized_tsc())
return;
@@ -190,6 +187,7 @@ void check_tsc_sync_target(void)
{
int cpus = 2;
+ /* Also aborts if there is no TSC. */
if (unsynchronized_tsc() || tsc_clocksource_reliable)
return;