Merge branches 'release', 'asus', 'sony-laptop' and 'thinkpad' into release

[pandora-kernel.git] / arch / powerpc / kernel / module_64.c

diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index 75c7c4f..3a82b02 100644 (file)
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -24,6 +24,7 @@
 #include <asm/module.h>
 #include <asm/uaccess.h>
 #include <asm/firmware.h>
+#include <linux/sort.h>
 
 #include "setup.h"
 
@@ -81,25 +82,23 @@ static struct ppc64_stub_entry ppc64_stub =
    different addend) */
 static unsigned int count_relocs(const Elf64_Rela *rela, unsigned int num)
 {
-       unsigned int i, j, ret = 0;
+       unsigned int i, r_info, r_addend, _count_relocs;
 
        /* FIXME: Only count external ones --RR */
-       /* Sure, this is order(n^2), but it's usually short, and not
-           time critical */
-       for (i = 0; i < num; i++) {
+       _count_relocs = 0;
+       r_info = 0;
+       r_addend = 0;
+       for (i = 0; i < num; i++)
                /* Only count 24-bit relocs, others don't need stubs */
-               if (ELF64_R_TYPE(rela[i].r_info) != R_PPC_REL24)
-                       continue;
-               for (j = 0; j < i; j++) {
-                       /* If this addend appeared before, it's
-                           already been counted */
-                       if (rela[i].r_info == rela[j].r_info
-                           && rela[i].r_addend == rela[j].r_addend)
-                               break;
+               if (ELF64_R_TYPE(rela[i].r_info) == R_PPC_REL24 &&
+                   (r_info != ELF64_R_SYM(rela[i].r_info) ||
+                    r_addend != rela[i].r_addend)) {
+                       _count_relocs++;
+                       r_info = ELF64_R_SYM(rela[i].r_info);
+                       r_addend = rela[i].r_addend;
                }
-               if (j == i) ret++;
-       }
-       return ret;
+
+       return _count_relocs;
 }
 
 void *module_alloc(unsigned long size)
@@ -118,6 +117,44 @@ void module_free(struct module *mod, void *module_region)
            table entries. */
 }
 
+static int relacmp(const void *_x, const void *_y)
+{
+       const Elf64_Rela *x, *y;
+
+       y = (Elf64_Rela *)_x;
+       x = (Elf64_Rela *)_y;
+
+       /* Compare the entire r_info (as opposed to ELF64_R_SYM(r_info) only) to
+        * make the comparison cheaper/faster. It won't affect the sorting or
+        * the counting algorithms' performance
+        */
+       if (x->r_info < y->r_info)
+               return -1;
+       else if (x->r_info > y->r_info)
+               return 1;
+       else if (x->r_addend < y->r_addend)
+               return -1;
+       else if (x->r_addend > y->r_addend)
+               return 1;
+       else
+               return 0;
+}
+
+static void relaswap(void *_x, void *_y, int size)
+{
+       uint64_t *x, *y, tmp;
+       int i;
+
+       y = (uint64_t *)_x;
+       x = (uint64_t *)_y;
+
+       for (i = 0; i < sizeof(Elf64_Rela) / sizeof(uint64_t); i++) {
+               tmp = x[i];
+               x[i] = y[i];
+               y[i] = tmp;
+       }
+}
+
 /* Get size of potential trampolines required. */
 static unsigned long get_stubs_size(const Elf64_Ehdr *hdr,
                                    const Elf64_Shdr *sechdrs)
@@ -133,6 +170,16 @@ static unsigned long get_stubs_size(const Elf64_Ehdr *hdr,
                        DEBUGP("Ptr: %p.  Number: %lu\n",
                               (void *)sechdrs[i].sh_addr,
                               sechdrs[i].sh_size / sizeof(Elf64_Rela));
+
+                       /* Sort the relocation information based on a symbol and
+                        * addend key. This is a stable O(n*log n) complexity
+                        * alogrithm but it will reduce the complexity of
+                        * count_relocs() to linear complexity O(n)
+                        */
+                       sort((void *)sechdrs[i].sh_addr,
+                            sechdrs[i].sh_size / sizeof(Elf64_Rela),
+                            sizeof(Elf64_Rela), relacmp, relaswap);
+
                        relocs += count_relocs((void *)sechdrs[i].sh_addr,
                                               sechdrs[i].sh_size
                                               / sizeof(Elf64_Rela));
@@ -343,7 +390,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
                        /* Simply set it */
                        *(u32 *)location = value;
                        break;
-                       
+
                case R_PPC64_ADDR64:
                        /* Simply set it */
                        *(unsigned long *)location = value;
@@ -399,7 +446,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
                        }
 
                        /* Only replace bits 2 through 26 */
-                       *(uint32_t *)location 
+                       *(uint32_t *)location
                                = (*(uint32_t *)location & ~0x03fffffc)
                                | (value & 0x03fffffc);
                        break;