[IA64] MCA/INIT: avoid reading INIT record during INIT event

Reading the INIT record from SAL during the INIT event has proved to be
unreliable, and a source of hangs during INIT processing.  The new
MCA/INIT handlers remove the need to get the INIT record from SAL.
Change salinfo.c so mca.c can just flag that a new record is available,
without having to read the record during INIT processing.  This patch
can be applied without the new MCA/INIT handlers.

Also clean up some usage of NR_CPUS which should have been using
cpu_online().

Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 34 insertions, 28 deletions

diff --git a/arch/ia64/kernel/salinfo.c b/arch/ia64/kernel/salinfo.c
index 6f0cc7a6634e..ca68e6e44a72 100644
--- a/arch/ia64/kernel/salinfo.c
+++ b/arch/ia64/kernel/salinfo.c
@@ -22,6 +22,11 @@
  *
  * Dec  5 2004  kaos@sgi.com
  *   Standardize which records are cleared automatically.
+ *
+ * Aug 18 2005  kaos@sgi.com
+ *   mca.c may not pass a buffer, a NULL buffer just indicates that a new
+ *   record is available in SAL.
+ *   Replace some NR_CPUS by cpus_online, for hotplug cpu.
  */
 
 #include <linux/types.h>
@@ -193,7 +198,7 @@ shift1_data_saved (struct salinfo_data *data, int shift)
  * The buffer passed from mca.c points to the output from ia64_log_get. This is
  * a persistent buffer but its contents can change between the interrupt and
  * when user space processes the record.  Save the record id to identify
- * changes.
+ * changes.  If the buffer is NULL then just update the bitmap.
  */
 void
 salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe)
@@ -206,27 +211,29 @@ salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe)
 
         BUG_ON(type >= ARRAY_SIZE(salinfo_log_name));
 
-        if (irqsafe)
-                spin_lock_irqsave(&data_saved_lock, flags);
-        for (i = 0, data_saved = data->data_saved; i < saved_size; ++i, ++data_saved) {
-                if (!data_saved->buffer)
-                        break;
-        }
-        if (i == saved_size) {
-                if (!data->saved_num) {
-                        shift1_data_saved(data, 0);
-                        data_saved = data->data_saved + saved_size - 1;
-                } else
-                        data_saved = NULL;
-        }
-        if (data_saved) {
-                data_saved->cpu = smp_processor_id();
-                data_saved->id = ((sal_log_record_header_t *)buffer)->id;
-                data_saved->size = size;
-                data_saved->buffer = buffer;
+        if (buffer) {
+                if (irqsafe)
+                        spin_lock_irqsave(&data_saved_lock, flags);
+                for (i = 0, data_saved = data->data_saved; i < saved_size; ++i, ++data_saved) {
+                        if (!data_saved->buffer)
+                                break;
+                }
+                if (i == saved_size) {
+                        if (!data->saved_num) {
+                                shift1_data_saved(data, 0);
+                                data_saved = data->data_saved + saved_size - 1;
+                        } else
+                                data_saved = NULL;
+                }
+                if (data_saved) {
+                        data_saved->cpu = smp_processor_id();
+                        data_saved->id = ((sal_log_record_header_t *)buffer)->id;
+                        data_saved->size = size;
+                        data_saved->buffer = buffer;
+                }
+                if (irqsafe)
+                        spin_unlock_irqrestore(&data_saved_lock, flags);
         }
-        if (irqsafe)
-                spin_unlock_irqrestore(&data_saved_lock, flags);
 
         if (!test_and_set_bit(smp_processor_id(), &data->cpu_event)) {
                 if (irqsafe)
@@ -244,7 +251,7 @@ salinfo_timeout_check(struct salinfo_data *data)
         int i;
         if (!data->open)
                 return;
-        for (i = 0; i < NR_CPUS; ++i) {
+        for_each_online_cpu(i) {
                 if (test_bit(i, &data->cpu_event)) {
                         /* double up() is not a problem, user space will see no
                          * records for the additional "events".
@@ -291,7 +298,7 @@ retry:
 
         n = data->cpu_check;
         for (i = 0; i < NR_CPUS; i++) {
-                if (test_bit(n, &data->cpu_event)) {
+                if (test_bit(n, &data->cpu_event) && cpu_online(n)) {
                         cpu = n;
                         break;
                 }
@@ -585,11 +592,10 @@ salinfo_init(void)
 
                 /* we missed any events before now */
                 online = 0;
-                for (j = 0; j < NR_CPUS; j++)
-                        if (cpu_online(j)) {
-                                set_bit(j, &data->cpu_event);
-                                ++online;
-                        }
+                for_each_online_cpu(j) {
+                        set_bit(j, &data->cpu_event);
+                        ++online;
+                }
                 sema_init(&data->sem, online);
 
                 *sdir++ = dir;