kernel - Reenable acpi sleep states

* Reenable acpi sleep state handling by default, by setting
  machdep.cpu_idle_hlt to 2 by default.

diff --git a/sys/platform/pc32/i386/machdep.c b/sys/platform/pc32/i386/machdep.c
index 5eaed51..59f2a65 100644 (file)
--- a/sys/platform/pc32/i386/machdep.c
+++ b/sys/platform/pc32/i386/machdep.c
@@ -877,18 +877,10 @@ cpu_halt(void)
  *      the possibility that no IPI will occur and in such cases
  *      lwkt_switch() sets TDF_IDLE_NOHLT.
  *
- * WARNING: On a SMP system the ACPI halt code can sometimes cause IPIs
- *         to be completely lost.  And I mean completely... vector never
- *         gets delivered.  Because of this we default to NOT using the
- *         ACPI halt code.  If you want to use the ACPI halt code anyway
- *         use sysctl machdep.cpu_idle_hlt=2.
- *
- *         This wasn't a huge deal before since our IPIs were queued, but
- *         now that we have a separate per-cpu Xtimer IPI and now that
- *         our Xinvltlb IPI is synchronous a missed IPI can cause total
- *         havoc.
+ * NOTE: cpu_idle_hlt again defaults to 2 (use ACPI sleep states).  Set to
+ *      1 to just use hlt and for debugging purposes.
  */
-static int     cpu_idle_hlt = 1;
+static int     cpu_idle_hlt = 2;
 static int     cpu_idle_hltcnt;
 static int     cpu_idle_spincnt;
 SYSCTL_INT(_machdep, OID_AUTO, cpu_idle_hlt, CTLFLAG_RW,

diff --git a/sys/platform/pc64/x86_64/machdep.c b/sys/platform/pc64/x86_64/machdep.c
index 045c28d..85b8bd3 100644 (file)
--- a/sys/platform/pc64/x86_64/machdep.c
+++ b/sys/platform/pc64/x86_64/machdep.c
@@ -902,18 +902,10 @@ cpu_halt(void)
  *      the possibility that no IPI will occur and in such cases
  *      lwkt_switch() sets TDF_IDLE_NOHLT.
  *
- * WARNING: On a SMP system the ACPI halt code can sometimes cause IPIs
- *         to be completely lost.  And I mean completely... vector never
- *         gets delivered.  Because of this we default to NOT using the
- *         ACPI halt code.  If you want to use the ACPI halt code anyway
- *         use sysctl machdep.cpu_idle_hlt=2.
- *
- *         This wasn't a huge deal before since our IPIs were queued, but
- *         now that we have a separate per-cpu Xtimer IPI and now that
- *         our Xinvltlb IPI is synchronous a missed IPI can cause total
- *         havoc.
+ * NOTE: cpu_idle_hlt again defaults to 2 (use ACPI sleep states).  Set to
+ *      1 to just use hlt and for debugging purposes.
  */
-static int     cpu_idle_hlt = 1;
+static int     cpu_idle_hlt = 2;
 static int     cpu_idle_hltcnt;
 static int     cpu_idle_spincnt;
 SYSCTL_INT(_machdep, OID_AUTO, cpu_idle_hlt, CTLFLAG_RW,