[SPARC64]: Kill pgtable quicklists and use SLAB.

Taking a nod from the powerpc port.

With the per-cpu caching of both the page allocator and SLAB, the
pgtable quicklist scheme becomes relatively silly and primitive.

Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 44 insertions, 166 deletions

diff --git a/arch/sparc64/kernel/sparc64_ksyms.c b/arch/sparc64/kernel/sparc64_ksyms.c
index 3c06bfb92a8c..f1f01378d079 100644
--- a/arch/sparc64/kernel/sparc64_ksyms.c
+++ b/arch/sparc64/kernel/sparc64_ksyms.c
@@ -241,10 +241,6 @@ EXPORT_SYMBOL(verify_compat_iovec);
 #endif
 
 EXPORT_SYMBOL(dump_fpu);
-EXPORT_SYMBOL(pte_alloc_one_kernel);
-#ifndef CONFIG_SMP
-EXPORT_SYMBOL(pgt_quicklists);
-#endif
 EXPORT_SYMBOL(put_fs_struct);
 
 /* math-emu wants this */
diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index 936ae1a594ac..7c456afaa9a5 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -141,26 +141,25 @@ unsigned long sparc64_kern_sec_context __read_mostly;
 
 int bigkernel = 0;
 
-/* XXX Tune this... */
-#define PGT_CACHE_LOW   25
-#define PGT_CACHE_HIGH  50
+kmem_cache_t *pgtable_cache __read_mostly;
 
-#ifndef CONFIG_SMP
-struct pgtable_cache_struct pgt_quicklists;
-#endif
+static void zero_ctor(void *addr, kmem_cache_t *cache, unsigned long flags)
+{
+        clear_page(addr);
+}
 
-void check_pgt_cache(void)
+void pgtable_cache_init(void)
 {
-        preempt_disable();
-        if (pgtable_cache_size > PGT_CACHE_HIGH) {
-                do {
-                        if (pgd_quicklist)
-                                free_pgd_slow(get_pgd_fast());
-                        if (pte_quicklist)
-                                free_pte_slow(pte_alloc_one_fast());
-                } while (pgtable_cache_size > PGT_CACHE_LOW);
+        pgtable_cache = kmem_cache_create("pgtable_cache",
+                                          PAGE_SIZE, PAGE_SIZE,
+                                          SLAB_HWCACHE_ALIGN |
+                                          SLAB_MUST_HWCACHE_ALIGN,
+                                          zero_ctor,
+                                          NULL);
+        if (!pgtable_cache) {
+                prom_printf("pgtable_cache_init(): Could not create!\n");
+                prom_halt();
         }
-        preempt_enable();
 }
 
 #ifdef CONFIG_DEBUG_DCFLUSH
@@ -340,7 +339,6 @@ void show_mem(void)
                nr_swap_pages << (PAGE_SHIFT-10));
         printk("%ld pages of RAM\n", num_physpages);
         printk("%d free pages\n", nr_free_pages());
-        printk("%d pages in page table cache\n",pgtable_cache_size);
 }
 
 void mmu_info(struct seq_file *m)
diff --git a/include/asm-sparc64/cpudata.h b/include/asm-sparc64/cpudata.h
index 45a9a2cfaf79..f7c0faede8b8 100644
--- a/include/asm-sparc64/cpudata.h
+++ b/include/asm-sparc64/cpudata.h
@@ -17,14 +17,7 @@ typedef struct {
         unsigned long   clock_tick;     /* %tick's per second */
         unsigned long   udelay_val;
 
-        /* Dcache line 2 */
-        unsigned int    pgcache_size;
-        unsigned int    __pad1;
-        unsigned long   *pte_cache;
-        unsigned long   *pgd_cache;
-        unsigned long   __pad2;
-
-        /* Dcache line 3, rarely used */
+        /* Dcache line 2, rarely used */
         unsigned int    dcache_size;
         unsigned int    dcache_line_size;
         unsigned int    icache_size;
diff --git a/include/asm-sparc64/pgalloc.h b/include/asm-sparc64/pgalloc.h
index ecea1bbdc115..12e4a273bd43 100644
--- a/include/asm-sparc64/pgalloc.h
+++ b/include/asm-sparc64/pgalloc.h
@@ -6,6 +6,7 @@
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/slab.h>
 
 #include <asm/spitfire.h>
 #include <asm/cpudata.h>
@@ -13,164 +14,59 @@
 #include <asm/page.h>
 
 /* Page table allocation/freeing. */
-#ifdef CONFIG_SMP
-/* Sliiiicck */
-#define pgt_quicklists  local_cpu_data()
-#else
-extern struct pgtable_cache_struct {
-        unsigned long *pgd_cache;
-        unsigned long *pte_cache;
-        unsigned int pgcache_size;
-} pgt_quicklists;
-#endif
-#define pgd_quicklist           (pgt_quicklists.pgd_cache)
-#define pte_quicklist           (pgt_quicklists.pte_cache)
-#define pgtable_cache_size      (pgt_quicklists.pgcache_size)
+extern kmem_cache_t *pgtable_cache;
 
-static inline void free_pgd_fast(pgd_t *pgd)
+static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-        preempt_disable();
-        *(unsigned long *)pgd = (unsigned long) pgd_quicklist;
-        pgd_quicklist = (unsigned long *) pgd;
-        pgtable_cache_size++;
-        preempt_enable();
+        return kmem_cache_alloc(pgtable_cache, GFP_KERNEL);
 }
 
-static inline pgd_t *get_pgd_fast(void)
+static inline void pgd_free(pgd_t *pgd)
 {
-        unsigned long *ret;
-
-        preempt_disable();
-        if((ret = pgd_quicklist) != NULL) {
-                pgd_quicklist = (unsigned long *)(*ret);
-                ret[0] = 0;
-                pgtable_cache_size--;
-                preempt_enable();
-        } else {
-                preempt_enable();
-                ret = (unsigned long *) __get_free_page(GFP_KERNEL|__GFP_REPEAT);
-                if(ret)
-                        memset(ret, 0, PAGE_SIZE);
-        }
-        return (pgd_t *)ret;
-}
-
-static inline void free_pgd_slow(pgd_t *pgd)
-{
-        free_page((unsigned long)pgd);
+        kmem_cache_free(pgtable_cache, pgd);
 }
 
 #define pud_populate(MM, PUD, PMD)      pud_set(PUD, PMD)
 
-static inline pmd_t *pmd_alloc_one_fast(void)
-{
-        unsigned long *ret;
-
-        preempt_disable();
-        ret = (unsigned long *) pte_quicklist;
-        if (likely(ret)) {
-                pte_quicklist = (unsigned long *)(*ret);
-                ret[0] = 0;
-                pgtable_cache_size--;
-        }
-        preempt_enable();
-
-        return (pmd_t *) ret;
-}
-
-static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
-{
-        pmd_t *pmd;
-
-        pmd = pmd_alloc_one_fast();
-        if (unlikely(!pmd)) {
-                pmd = (pmd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
-                if (pmd)
-                        memset(pmd, 0, PAGE_SIZE);
-        }
-        return pmd;
-}
-
-static inline void free_pmd_fast(pmd_t *pmd)
-{
-        preempt_disable();
-        *(unsigned long *)pmd = (unsigned long) pte_quicklist;
-        pte_quicklist = (unsigned long *) pmd;
-        pgtable_cache_size++;
-        preempt_enable();
-}
-
-static inline void free_pmd_slow(pmd_t *pmd)
-{
-        free_page((unsigned long)pmd);
-}
-
-#define pmd_populate_kernel(MM, PMD, PTE)       pmd_set(PMD, PTE)
-#define pmd_populate(MM,PMD,PTE_PAGE)           \
-        pmd_populate_kernel(MM,PMD,page_address(PTE_PAGE))
-
-static inline pte_t *pte_alloc_one_fast(void)
+static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-        unsigned long *ret;
-
-        preempt_disable();
-        ret = (unsigned long *) pte_quicklist;
-        if (likely(ret)) {
-                pte_quicklist = (unsigned long *)(*ret);
-                ret[0] = 0;
-                pgtable_cache_size--;
-        }
-        preempt_enable();
-
-        return (pte_t *) ret;
+        return kmem_cache_alloc(pgtable_cache,
+                                GFP_KERNEL|__GFP_REPEAT);
 }
 
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
+static inline void pmd_free(pmd_t *pmd)
 {
-        pte_t *ptep = pte_alloc_one_fast();
-
-        if (likely(ptep))
-                return ptep;
-
-        return (pte_t *) get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
+        kmem_cache_free(pgtable_cache, pmd);
 }
 
-static inline struct page *pte_alloc_one(struct mm_struct *mm, unsigned long addr)
+static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
+                                          unsigned long address)
 {
-        pte_t *pte = pte_alloc_one_fast();
-
-        if (likely(pte))
-                return virt_to_page(pte);
-
-        return alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
+        return kmem_cache_alloc(pgtable_cache,
+                                GFP_KERNEL|__GFP_REPEAT);
 }
 
-static inline void free_pte_fast(pte_t *pte)
+static inline struct page *pte_alloc_one(struct mm_struct *mm,
+                                         unsigned long address)
 {
-        preempt_disable();
-        *(unsigned long *)pte = (unsigned long) pte_quicklist;
-        pte_quicklist = (unsigned long *) pte;
-        pgtable_cache_size++;
-        preempt_enable();
+        return virt_to_page(pte_alloc_one_kernel(mm, address));
 }
-
-static inline void free_pte_slow(pte_t *pte)
-{
-        free_page((unsigned long) pte);
-}
-
+                
 static inline void pte_free_kernel(pte_t *pte)
 {
-        free_pte_fast(pte);
+        kmem_cache_free(pgtable_cache, pte);
 }
 
 static inline void pte_free(struct page *ptepage)
 {
-        free_pte_fast(page_address(ptepage));
+        pte_free_kernel(page_address(ptepage));
 }
 
-#define pmd_free(pmd)           free_pmd_fast(pmd)
-#define pgd_free(pgd)           free_pgd_fast(pgd)
-#define pgd_alloc(mm)           get_pgd_fast()
+
+#define pmd_populate_kernel(MM, PMD, PTE)       pmd_set(PMD, PTE)
+#define pmd_populate(MM,PMD,PTE_PAGE)           \
+        pmd_populate_kernel(MM,PMD,page_address(PTE_PAGE))
+
+#define check_pgt_cache()       do { } while (0)
 
 #endif /* _SPARC64_PGALLOC_H */
diff --git a/include/asm-sparc64/pgtable.h b/include/asm-sparc64/pgtable.h
index f3ba1e058195..77ba0b6cc1ce 100644
--- a/include/asm-sparc64/pgtable.h
+++ b/include/asm-sparc64/pgtable.h
@@ -432,12 +432,7 @@ extern unsigned long get_fb_unmapped_area(struct file *filp, unsigned long,
                                           unsigned long);
 #define HAVE_ARCH_FB_UNMAPPED_AREA
 
-/*
- * No page table caches to initialise
- */
-#define pgtable_cache_init()    do { } while (0)
-
-extern void check_pgt_cache(void);
+extern void pgtable_cache_init(void);
 
 #endif /* !(__ASSEMBLY__) */