tile: support CONFIG_PREEMPT

This change adds support for CONFIG_PREEMPT (full kernel preemption).
In addition to the core support, this change includes a number
of places where we fix up uses of smp_processor_id() and per-cpu
variables.  I also eliminate the PAGE_HOME_HERE and PAGE_HOME_UNKNOWN
values for page homing, as it turns out they weren't being used.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/arch/tile/lib/memcpy_tile64.c b/arch/tile/lib/memcpy_tile64.c
index 3bc4b4e40d93..0290c222847b 100644
--- a/arch/tile/lib/memcpy_tile64.c
+++ b/arch/tile/lib/memcpy_tile64.c
@@ -65,7 +65,7 @@ static void memcpy_multicache(void *dest, const void *source,
         pmd_t *pmdp;
         pte_t *ptep;
         int type0, type1;
-        int cpu = get_cpu();
+        int cpu = smp_processor_id();
 
         /*
          * Disable interrupts so that we don't recurse into memcpy()
@@ -126,7 +126,6 @@ static void memcpy_multicache(void *dest, const void *source,
         kmap_atomic_idx_pop();
         sim_allow_multiple_caching(0);
         local_irq_restore(flags);
-        put_cpu();
 }
 
 /*
@@ -137,6 +136,9 @@ static void memcpy_multicache(void *dest, const void *source,
 static unsigned long fast_copy(void *dest, const void *source, int len,
                                memcpy_t func)
 {
+        int cpu = get_cpu();
+        unsigned long retval;
+
         /*
          * Check if it's big enough to bother with.  We may end up doing a
          * small copy via TLB manipulation if we're near a page boundary,
@@ -158,7 +160,7 @@ retry_source:
                     !hv_pte_get_readable(src_pte) ||
                     hv_pte_get_mode(src_pte) != HV_PTE_MODE_CACHE_TILE_L3)
                         break;
-                if (get_remote_cache_cpu(src_pte) == smp_processor_id())
+                if (get_remote_cache_cpu(src_pte) == cpu)
                         break;
                 src_page = pfn_to_page(pte_pfn(src_pte));
                 get_page(src_page);
@@ -235,7 +237,9 @@ retry_dest:
                 len -= copy_size;
         }
 
-        return func(dest, source, len);
+        retval = func(dest, source, len);
+        put_cpu();
+        return retval;
 }
 
 void *memcpy(void *to, const void *from, __kernel_size_t n)