[PATCH] ppc64: Clean up per cpu usage in segment table code.

From: Anton Blanchard <anton@samba.org>

Clean up per cpu usage in segment table code.

diff --git a/arch/ppc64/kernel/stab.c b/arch/ppc64/kernel/stab.c
index 8e2d35c81f1a52d1ae6bd3e9b963a4e53ae379f3..b17b7fc9a9b57767a39ce1450efddd217a6120a9 100644 (file)
--- a/arch/ppc64/kernel/stab.c
+++ b/arch/ppc64/kernel/stab.c
@@ -143,7 +143,7 @@ static int make_ste(unsigned long stab, unsigned long esid, unsigned long vsid)
 static inline void __ste_allocate(unsigned long esid, unsigned long vsid)
 {
        unsigned char stab_entry;
-       unsigned long *offset;
+       unsigned long offset;
        int region_id = REGION_ID(esid << SID_SHIFT);
 
        stab_entry = make_ste(get_paca()->xStab_data.virt, esid, vsid);
@@ -151,11 +151,12 @@ static inline void __ste_allocate(unsigned long esid, unsigned long vsid)
        if (region_id != USER_REGION_ID)
                return;
 
-       offset = &__get_cpu_var(stab_cache_ptr);
-       if (*offset < NR_STAB_CACHE_ENTRIES) {
-               __get_cpu_var(stab_cache[*offset]) = stab_entry;
-       }
-       (*offset)++;
+       offset = __get_cpu_var(stab_cache_ptr);
+       if (offset < NR_STAB_CACHE_ENTRIES)
+               __get_cpu_var(stab_cache[offset++]) = stab_entry;
+       else
+               offset = NR_STAB_CACHE_ENTRIES+1;
+       __get_cpu_var(stab_cache_ptr) = offset;
 }
 
 /*
@@ -241,15 +242,15 @@ void flush_stab(struct task_struct *tsk, struct mm_struct *mm)
 {
        STE *stab = (STE *) get_paca()->xStab_data.virt;
        STE *ste;
-       unsigned long *offset = &__get_cpu_var(stab_cache_ptr);
+       unsigned long offset = __get_cpu_var(stab_cache_ptr);
 
        /* Force previous translations to complete. DRENG */
        asm volatile("isync" : : : "memory");
 
-       if (*offset <= NR_STAB_CACHE_ENTRIES) {
+       if (offset <= NR_STAB_CACHE_ENTRIES) {
                int i;
 
-               for (i = 0; i < *offset; i++) {
+               for (i = 0; i < offset; i++) {
                        ste = stab + __get_cpu_var(stab_cache[i]);
                        ste->dw0.dw0.v = 0;
                }
@@ -274,7 +275,7 @@ void flush_stab(struct task_struct *tsk, struct mm_struct *mm)
 
        asm volatile("sync; slbia; sync":::"memory");
 
-       *offset = 0;
+       __get_cpu_var(stab_cache_ptr) = 0;
 
        preload_stab(tsk, mm);
 }
@@ -357,7 +358,7 @@ static inline void __slb_allocate(unsigned long esid, unsigned long vsid,
 {
        int large = 0;
        int region_id = REGION_ID(esid << SID_SHIFT);
-       unsigned long *offset;
+       unsigned long offset;
 
        if (cur_cpu_spec->cpu_features & CPU_FTR_16M_PAGE) {
                if (region_id == KERNEL_REGION_ID)
@@ -371,11 +372,12 @@ static inline void __slb_allocate(unsigned long esid, unsigned long vsid,
        if (region_id != USER_REGION_ID)
                return;
 
-       offset = &__get_cpu_var(stab_cache_ptr);
-       if (*offset < NR_STAB_CACHE_ENTRIES) {
-               __get_cpu_var(stab_cache[*offset]) = esid;
-       }
-       (*offset)++;
+       offset = __get_cpu_var(stab_cache_ptr);
+       if (offset < NR_STAB_CACHE_ENTRIES)
+               __get_cpu_var(stab_cache[offset++]) = esid;
+       else
+               offset = NR_STAB_CACHE_ENTRIES+1;
+       __get_cpu_var(stab_cache_ptr) = offset;
 }
 
 /*
@@ -454,9 +456,9 @@ static void preload_slb(struct task_struct *tsk, struct mm_struct *mm)
 /* Flush all user entries from the segment table of the current processor. */
 void flush_slb(struct task_struct *tsk, struct mm_struct *mm)
 {
-       unsigned long *offset = &__get_cpu_var(stab_cache_ptr);
+       unsigned long offset = __get_cpu_var(stab_cache_ptr);
 
-       if (*offset <= NR_STAB_CACHE_ENTRIES) {
+       if (offset <= NR_STAB_CACHE_ENTRIES) {
                int i;
                union {
                        unsigned long word0;
@@ -464,7 +466,7 @@ void flush_slb(struct task_struct *tsk, struct mm_struct *mm)
                } esid_data;
 
                asm volatile("isync" : : : "memory");
-               for (i = 0; i < *offset; i++) {
+               for (i = 0; i < offset; i++) {
                        esid_data.word0 = 0;
                        esid_data.data.esid = __get_cpu_var(stab_cache[i]);
                        asm volatile("slbie %0" : : "r" (esid_data));
@@ -474,7 +476,7 @@ void flush_slb(struct task_struct *tsk, struct mm_struct *mm)
                asm volatile("isync; slbia; isync" : : : "memory");
        }
 
-       *offset = 0;
+       __get_cpu_var(stab_cache_ptr) = 0;
 
        preload_slb(tsk, mm);
 }