x86, cpa: remove cpa pool code

Interrupt context no longer splits large page in cpa(). So we can do away
with cpa memory pool code.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: arjan@linux.intel.com
Cc: venkatesh.pallipadi@intel.com
Cc: jeremy@goop.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 44ccb02..7478080 100644 (file)
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -1051,7 +1051,6 @@ void __init mem_init(void)
        if (boot_cpu_data.wp_works_ok < 0)
                test_wp_bit();
 
-       cpa_init();
        save_pg_dir();
        zap_low_mappings();
 }

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 9d7587a..f54a4d9 100644 (file)
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -889,8 +889,6 @@ void __init mem_init(void)
                reservedpages << (PAGE_SHIFT-10),
                datasize >> 10,
                initsize >> 10);
-
-       cpa_init();
 }
 
 void free_init_pages(char *what, unsigned long begin, unsigned long end)

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 162812b..f5e8663 100644 (file)
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -447,114 +447,17 @@ out_unlock:
        return do_split;
 }
 
-static LIST_HEAD(page_pool);
-static unsigned long pool_size, pool_pages, pool_low;
-static unsigned long pool_used, pool_failed;
-
-static void cpa_fill_pool(struct page **ret)
-{
-       gfp_t gfp = GFP_KERNEL;
-       unsigned long flags;
-       struct page *p;
-
-       /*
-        * Avoid recursion (on debug-pagealloc) and also signal
-        * our priority to get to these pagetables:
-        */
-       if (current->flags & PF_MEMALLOC)
-               return;
-       current->flags |= PF_MEMALLOC;
-
-       /*
-        * Allocate atomically from atomic contexts:
-        */
-       if (in_atomic() || irqs_disabled() || debug_pagealloc)
-               gfp =  GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
-
-       while (pool_pages < pool_size || (ret && !*ret)) {
-               p = alloc_pages(gfp, 0);
-               if (!p) {
-                       pool_failed++;
-                       break;
-               }
-               /*
-                * If the call site needs a page right now, provide it:
-                */
-               if (ret && !*ret) {
-                       *ret = p;
-                       continue;
-               }
-               spin_lock_irqsave(&pgd_lock, flags);
-               list_add(&p->lru, &page_pool);
-               pool_pages++;
-               spin_unlock_irqrestore(&pgd_lock, flags);
-       }
-
-       current->flags &= ~PF_MEMALLOC;
-}
-
-#define SHIFT_MB               (20 - PAGE_SHIFT)
-#define ROUND_MB_GB            ((1 << 10) - 1)
-#define SHIFT_MB_GB            10
-#define POOL_PAGES_PER_GB      16
-
-void __init cpa_init(void)
-{
-       struct sysinfo si;
-       unsigned long gb;
-
-       si_meminfo(&si);
-       /*
-        * Calculate the number of pool pages:
-        *
-        * Convert totalram (nr of pages) to MiB and round to the next
-        * GiB. Shift MiB to Gib and multiply the result by
-        * POOL_PAGES_PER_GB:
-        */
-       if (debug_pagealloc) {
-               gb = ((si.totalram >> SHIFT_MB) + ROUND_MB_GB) >> SHIFT_MB_GB;
-               pool_size = POOL_PAGES_PER_GB * gb;
-       } else {
-               pool_size = 1;
-       }
-       pool_low = pool_size;
-
-       cpa_fill_pool(NULL);
-       printk(KERN_DEBUG
-              "CPA: page pool initialized %lu of %lu pages preallocated\n",
-              pool_pages, pool_size);
-}
-
 static int split_large_page(pte_t *kpte, unsigned long address)
 {
        unsigned long flags, pfn, pfninc = 1;
        unsigned int i, level;
        pte_t *pbase, *tmp;
        pgprot_t ref_prot;
-       struct page *base;
+       struct page *base = alloc_pages(GFP_KERNEL, 0);
+       if (!base)
+               return -ENOMEM;
 
-       /*
-        * Get a page from the pool. The pool list is protected by the
-        * pgd_lock, which we have to take anyway for the split
-        * operation:
-        */
        spin_lock_irqsave(&pgd_lock, flags);
-       if (list_empty(&page_pool)) {
-               spin_unlock_irqrestore(&pgd_lock, flags);
-               base = NULL;
-               cpa_fill_pool(&base);
-               if (!base)
-                       return -ENOMEM;
-               spin_lock_irqsave(&pgd_lock, flags);
-       } else {
-               base = list_first_entry(&page_pool, struct page, lru);
-               list_del(&base->lru);
-               pool_pages--;
-
-               if (pool_pages < pool_low)
-                       pool_low = pool_pages;
-       }
-
        /*
         * Check for races, another CPU might have split this page
         * up for us already:
@@ -611,11 +514,8 @@ out_unlock:
         * If we dropped out via the lookup_address check under
         * pgd_lock then stick the page back into the pool:
         */
-       if (base) {
-               list_add(&base->lru, &page_pool);
-               pool_pages++;
-       } else
-               pool_used++;
+       if (base)
+               __free_page(base);
        spin_unlock_irqrestore(&pgd_lock, flags);
 
        return 0;
@@ -899,8 +799,6 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages,
                cpa_flush_all(cache);
 
 out:
-       cpa_fill_pool(NULL);
-
        return ret;
 }
 
@@ -1178,53 +1076,8 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
         * but that can deadlock->flush only current cpu:
         */
        __flush_tlb_all();
-
-       /*
-        * Try to refill the page pool here. We can do this only after
-        * the tlb flush.
-        */
-       cpa_fill_pool(NULL);
-}
-
-#ifdef CONFIG_DEBUG_FS
-static int dpa_show(struct seq_file *m, void *v)
-{
-       seq_puts(m, "DEBUG_PAGEALLOC\n");
-       seq_printf(m, "pool_size     : %lu\n", pool_size);
-       seq_printf(m, "pool_pages    : %lu\n", pool_pages);
-       seq_printf(m, "pool_low      : %lu\n", pool_low);
-       seq_printf(m, "pool_used     : %lu\n", pool_used);
-       seq_printf(m, "pool_failed   : %lu\n", pool_failed);
-
-       return 0;
-}
-
-static int dpa_open(struct inode *inode, struct file *filp)
-{
-       return single_open(filp, dpa_show, NULL);
 }
 
-static const struct file_operations dpa_fops = {
-       .open           = dpa_open,
-       .read           = seq_read,
-       .llseek         = seq_lseek,
-       .release        = single_release,
-};
-
-static int __init debug_pagealloc_proc_init(void)
-{
-       struct dentry *de;
-
-       de = debugfs_create_file("debug_pagealloc", 0600, NULL, NULL,
-                                &dpa_fops);
-       if (!de)
-               return -ENOMEM;
-
-       return 0;
-}
-__initcall(debug_pagealloc_proc_init);
-#endif
-
 #ifdef CONFIG_HIBERNATION
 
 bool kernel_page_present(struct page *page)

diff --git a/include/asm-x86/cacheflush.h b/include/asm-x86/cacheflush.h
index 0a5f718..8e205a1 100644 (file)
--- a/include/asm-x86/cacheflush.h
+++ b/include/asm-x86/cacheflush.h
@@ -99,8 +99,6 @@ int set_pages_rw(struct page *page, int numpages);
 
 void clflush_cache_range(void *addr, unsigned int size);
 
-void cpa_init(void);
-
 #ifdef CONFIG_DEBUG_RODATA
 void mark_rodata_ro(void);
 extern const int rodata_test_data;