x86, apic: Handle a bad TSC more gracefully

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kernel / apic / apic.c

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index ad28db7e6bdea3594a4bfad1d70d0c975ded7021..24b5894396a06c76b073435f52143f5ca420748f 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -67,7 +67,7 @@ EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
 /*
  * The highest APIC ID seen during enumeration.
  */
-unsigned int max_physical_apicid;
+static unsigned int max_physical_apicid;
 
 /*
  * Bitmask of physically existing CPUs:
@@ -1297,7 +1297,7 @@ void setup_local_APIC(void)
        unsigned int value, queued;
        int i, j, acked = 0;
        unsigned long long tsc = 0, ntsc;
-       long long max_loops = cpu_khz;
+       long long max_loops = cpu_khz ? cpu_khz : 1000000;
 
        if (cpu_has_tsc)
                rdtscll(tsc);
@@ -1342,17 +1342,6 @@ void setup_local_APIC(void)
        /* always use the value from LDR */
        early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
                logical_smp_processor_id();
-
-       /*
-        * Some NUMA implementations (NUMAQ) don't initialize apicid to
-        * node mapping during NUMA init.  Now that logical apicid is
-        * guaranteed to be known, give it another chance.  This is already
-        * a bit too late - percpu allocation has already happened without
-        * proper NUMA affinity.
-        */
-       if (apic->x86_32_numa_cpu_node)
-               set_apicid_to_node(early_per_cpu(x86_cpu_to_apicid, cpu),
-                                  apic->x86_32_numa_cpu_node(cpu));
 #endif
 
        /*
@@ -1394,7 +1383,7 @@ void setup_local_APIC(void)
                        break;
                }
                if (queued) {
-                       if (cpu_has_tsc) {
+                       if (cpu_has_tsc && cpu_khz) {
                                rdtscll(ntsc);
                                max_loops = (cpu_khz << 10) - (ntsc - tsc);
                        } else
@@ -2053,8 +2042,6 @@ void __init connect_bsp_APIC(void)
                imcr_pic_to_apic();
        }
 #endif
-       if (apic->enable_apic_mode)
-               apic->enable_apic_mode();
 }
 
 /**
@@ -2451,51 +2438,6 @@ static void apic_pm_activate(void) { }
 
 #ifdef CONFIG_X86_64
 
-static int apic_cluster_num(void)
-{
-       int i, clusters, zeros;
-       unsigned id;
-       u16 *bios_cpu_apicid;
-       DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
-
-       bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
-       bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
-
-       for (i = 0; i < nr_cpu_ids; i++) {
-               /* are we being called early in kernel startup? */
-               if (bios_cpu_apicid) {
-                       id = bios_cpu_apicid[i];
-               } else if (i < nr_cpu_ids) {
-                       if (cpu_present(i))
-                               id = per_cpu(x86_bios_cpu_apicid, i);
-                       else
-                               continue;
-               } else
-                       break;
-
-               if (id != BAD_APICID)
-                       __set_bit(APIC_CLUSTERID(id), clustermap);
-       }
-
-       /* Problem:  Partially populated chassis may not have CPUs in some of
-        * the APIC clusters they have been allocated.  Only present CPUs have
-        * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
-        * Since clusters are allocated sequentially, count zeros only if
-        * they are bounded by ones.
-        */
-       clusters = 0;
-       zeros = 0;
-       for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
-               if (test_bit(i, clustermap)) {
-                       clusters += 1 + zeros;
-                       zeros = 0;
-               } else
-                       ++zeros;
-       }
-
-       return clusters;
-}
-
 static int multi_checked;
 static int multi;
 
@@ -2540,20 +2482,7 @@ static void dmi_check_multi(void)
 int apic_is_clustered_box(void)
 {
        dmi_check_multi();
-       if (multi)
-               return 1;
-
-       if (!is_vsmp_box())
-               return 0;
-
-       /*
-        * ScaleMP vSMPowered boxes have one cluster per board and TSCs are
-        * not guaranteed to be synced between boards
-        */
-       if (apic_cluster_num() > 1)
-               return 1;
-
-       return 0;
+       return multi;
 }
 #endif