[IA64] __per_cpu_idtrs[] is a memory hog

__per_cpu_idtrs is statically allocated ... on CONFIG_NR_CPUS=4096
systems it hogs 16MB of memory. This is way too much for a quite
probably unused facility (only KVM uses dynamic TR registers).

Change to an array of pointers, and allocate entries as needed on
a per cpu basis.  Change the name too as the __per_cpu_ prefix is
confusing (this isn't a classic <linux/percpu.h> type object).

Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c
index 32f2639e9b0a..378b4833024f 100644
--- a/arch/ia64/kernel/mca.c
+++ b/arch/ia64/kernel/mca.c
@@ -1225,9 +1225,12 @@ static void mca_insert_tr(u64 iord)
         unsigned long psr;
         int cpu = smp_processor_id();
 
+        if (!ia64_idtrs[cpu])
+                return;
+
         psr = ia64_clear_ic();
         for (i = IA64_TR_ALLOC_BASE; i < IA64_TR_ALLOC_MAX; i++) {
-                p = &__per_cpu_idtrs[cpu][iord-1][i];
+                p = ia64_idtrs[cpu] + (iord - 1) * IA64_TR_ALLOC_MAX;
                 if (p->pte & 0x1) {
                         old_rr = ia64_get_rr(p->ifa);
                         if (old_rr != p->rr) {