11 files changed, 31 insertions, 18 deletions

diff --git a/arch/i386/kernel/cpu/intel.c b/arch/i386/kernel/cpu/intel.c
index 96a75d045835..a2c33c1a46c5 100644
--- a/arch/i386/kernel/cpu/intel.c
+++ b/arch/i386/kernel/cpu/intel.c
@@ -25,7 +25,7 @@ extern int trap_init_f00f_bug(void);
 /*
  * Alignment at which movsl is preferred for bulk memory copies.
  */
-struct movsl_mask movsl_mask;
+struct movsl_mask movsl_mask __read_mostly;
 #endif
 
 void __devinit early_intel_workaround(struct cpuinfo_x86 *c)
diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index d66bf489a2e9..8ac8e9fd5614 100644
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -68,21 +68,21 @@ EXPORT_SYMBOL(smp_num_siblings);
 #endif
 
 /* Package ID of each logical CPU */
-int phys_proc_id[NR_CPUS] = {[0 ... NR_CPUS-1] = BAD_APICID};
+int phys_proc_id[NR_CPUS] __read_mostly = {[0 ... NR_CPUS-1] = BAD_APICID};
 EXPORT_SYMBOL(phys_proc_id);
 
 /* Core ID of each logical CPU */
-int cpu_core_id[NR_CPUS] = {[0 ... NR_CPUS-1] = BAD_APICID};
+int cpu_core_id[NR_CPUS] __read_mostly = {[0 ... NR_CPUS-1] = BAD_APICID};
 EXPORT_SYMBOL(cpu_core_id);
 
-cpumask_t cpu_sibling_map[NR_CPUS];
+cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
 EXPORT_SYMBOL(cpu_sibling_map);
 
-cpumask_t cpu_core_map[NR_CPUS];
+cpumask_t cpu_core_map[NR_CPUS] __read_mostly;
 EXPORT_SYMBOL(cpu_core_map);
 
 /* bitmap of online cpus */
-cpumask_t cpu_online_map;
+cpumask_t cpu_online_map __read_mostly;
 EXPORT_SYMBOL(cpu_online_map);
 
 cpumask_t cpu_callin_map;
@@ -100,7 +100,7 @@ static int __devinitdata tsc_sync_disabled;
 struct cpuinfo_x86 cpu_data[NR_CPUS] __cacheline_aligned;
 EXPORT_SYMBOL(cpu_data);
 
-u8 x86_cpu_to_apicid[NR_CPUS] =
+u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly =
                         { [0 ... NR_CPUS-1] = 0xff };
 EXPORT_SYMBOL(x86_cpu_to_apicid);
 
@@ -550,10 +550,10 @@ extern struct {
 #ifdef CONFIG_NUMA
 
 /* which logical CPUs are on which nodes */
-cpumask_t node_2_cpu_mask[MAX_NUMNODES] =
+cpumask_t node_2_cpu_mask[MAX_NUMNODES] __read_mostly =
                                 { [0 ... MAX_NUMNODES-1] = CPU_MASK_NONE };
 /* which node each logical CPU is on */
-int cpu_2_node[NR_CPUS] = { [0 ... NR_CPUS-1] = 0 };
+int cpu_2_node[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = 0 };
 EXPORT_SYMBOL(cpu_2_node);
 
 /* set up a mapping between cpu and node. */
@@ -581,7 +581,7 @@ static inline void unmap_cpu_to_node(int cpu)
 
 #endif /* CONFIG_NUMA */
 
-u8 cpu_2_logical_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
+u8 cpu_2_logical_apicid[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
 
 static void map_cpu_to_logical_apicid(void)
 {
diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
index 2854c357377f..0ee9dee8af06 100644
--- a/arch/i386/kernel/time.c
+++ b/arch/i386/kernel/time.c
@@ -91,7 +91,7 @@ EXPORT_SYMBOL(rtc_lock);
 DEFINE_SPINLOCK(i8253_lock);
 EXPORT_SYMBOL(i8253_lock);
 
-struct timer_opts *cur_timer = &timer_none;
+struct timer_opts *cur_timer __read_mostly = &timer_none;
 
 /*
  * This is a special lock that is owned by the CPU and holds the index
diff --git a/arch/i386/kernel/timers/timer_hpet.c b/arch/i386/kernel/timers/timer_hpet.c
index d766e0963ac1..ef8dac5dd33b 100644
--- a/arch/i386/kernel/timers/timer_hpet.c
+++ b/arch/i386/kernel/timers/timer_hpet.c
@@ -18,7 +18,7 @@
 #include "mach_timer.h"
 #include <asm/hpet.h>
 
-static unsigned long hpet_usec_quotient;        /* convert hpet clks to usec */
+static unsigned long __read_mostly hpet_usec_quotient;  /* convert hpet clks to usec */
 static unsigned long tsc_hpet_quotient;         /* convert tsc to hpet clks */
 static unsigned long hpet_last;         /* hpet counter value at last tick*/
 static unsigned long last_tsc_low;      /* lsb 32 bits of Time Stamp Counter */
@@ -180,7 +180,7 @@ static int __init init_hpet(char* override)
 /************************************************************/
 
 /* tsc timer_opts struct */
-static struct timer_opts timer_hpet = {
+static struct timer_opts timer_hpet __read_mostly = {
         .name =                 "hpet",
         .mark_offset =          mark_offset_hpet,
         .get_offset =           get_offset_hpet,
diff --git a/arch/i386/kernel/vmlinux.lds.S b/arch/i386/kernel/vmlinux.lds.S
index 7e01a528a83a..761972f8cb6c 100644
--- a/arch/i386/kernel/vmlinux.lds.S
+++ b/arch/i386/kernel/vmlinux.lds.S
@@ -57,6 +57,9 @@ SECTIONS
         *(.data.cacheline_aligned)
   }
 
+  /* rarely changed data like cpu maps */
+  . = ALIGN(32);
+  .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) { *(.data.read_mostly) }
   _edata = .;                   /* End of data section */
 
   . = ALIGN(THREAD_SIZE);       /* init_task */
diff --git a/arch/x86_64/kernel/vmlinux.lds.S b/arch/x86_64/kernel/vmlinux.lds.S
index 73389f51c4e5..61c12758ca70 100644
--- a/arch/x86_64/kernel/vmlinux.lds.S
+++ b/arch/x86_64/kernel/vmlinux.lds.S
@@ -56,6 +56,10 @@ SECTIONS
   .data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
         *(.data.cacheline_aligned)
   }
+  . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
+  .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
+        *(.data.read_mostly)
+  }
 
 #define VSYSCALL_ADDR (-10*1024*1024)
 #define VSYSCALL_PHYS_ADDR ((LOADADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095))
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 460b5d475edd..6b11d6b2129f 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -271,7 +271,7 @@ static int random_write_wakeup_thresh = 128;
  * samples to avoid wasting CPU time and reduce lock contention.
  */
 
-static int trickle_thresh = INPUT_POOL_WORDS * 28;
+static int trickle_thresh __read_mostly = INPUT_POOL_WORDS * 28;
 
 static DEFINE_PER_CPU(int, trickle_count) = 0;
 
diff --git a/fs/bio.c b/fs/bio.c
index 3a1472acc361..ca8f7a850fe3 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -52,7 +52,7 @@ struct biovec_slab {
  */
 
 #define BV(x) { .nr_vecs = x, .name = "biovec-"__stringify(x) }
-static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] = {
+static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
         BV(1), BV(4), BV(16), BV(64), BV(128), BV(BIO_MAX_PAGES),
 };
 #undef BV
diff --git a/include/linux/cache.h b/include/linux/cache.h
index 4d767b93738a..2b66a36d85f0 100644
--- a/include/linux/cache.h
+++ b/include/linux/cache.h
@@ -13,6 +13,12 @@
 #define SMP_CACHE_BYTES L1_CACHE_BYTES
 #endif
 
+#ifdef CONFIG_X86
+#define __read_mostly __attribute__((__section__(".data.read_mostly")))
+#else
+#define __read_mostly
+#endif
+
 #ifndef ____cacheline_aligned
 #define ____cacheline_aligned __attribute__((__aligned__(SMP_CACHE_BYTES)))
 #endif
diff --git a/kernel/profile.c b/kernel/profile.c
index ad8cbb75ffa2..f89248e6d704 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -35,11 +35,11 @@ struct profile_hit {
 #define NR_PROFILE_GRP          (NR_PROFILE_HIT/PROFILE_GRPSZ)
 
 /* Oprofile timer tick hook */
-int (*timer_hook)(struct pt_regs *);
+int (*timer_hook)(struct pt_regs *) __read_mostly;
 
 static atomic_t *prof_buffer;
 static unsigned long prof_len, prof_shift;
-static int prof_on;
+static int prof_on __read_mostly;
 static cpumask_t prof_cpu_mask = CPU_MASK_ALL;
 #ifdef CONFIG_SMP
 static DEFINE_PER_CPU(struct profile_hit *[2], cpu_profile_hits);
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 04d664377f2c..10bed1c8c3c3 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -58,7 +58,7 @@ struct radix_tree_path {
 #define RADIX_TREE_INDEX_BITS  (8 /* CHAR_BIT */ * sizeof(unsigned long))
 #define RADIX_TREE_MAX_PATH (RADIX_TREE_INDEX_BITS/RADIX_TREE_MAP_SHIFT + 2)
 
-static unsigned long height_to_maxindex[RADIX_TREE_MAX_PATH];
+static unsigned long height_to_maxindex[RADIX_TREE_MAX_PATH] __read_mostly;
 
 /*
  * Radix tree node cache.