Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] Cannot use register_percpu_irq() from ia64_mca_init()
  [IA64] Initialize interrupts later (from init_IRQ())
  [IA64] enable ARCH_DMA_ADDR_T_64BIT
  [IA64] ioc3_serial: release resources in error return path
  [IA64] Stop using the deprecated __do_IRQ() code path
  [IA64] Remove unnecessary casts of private_data in perfmon.c
  [IA64] Fix missing iounmap in error path in cyclone.c
  [IA64] salinfo: sema_init instead of init_MUTEX
  [IA64] xen: use ARRAY_SIZE macro in xen_pv_ops.c
  [IA64] Use static const char * const in palinfo.c
  [IA64] remove asm/compat.h
  [IA64] Add CONFIG_STACKTRACE_SUPPORT
  [IA64] Move local_softirq_pending() definition
  [IA64] iommu: Add a dummy iommu_table.h file in IA64.
  [IA64] unwind - optimise linked-list searches for modules
  [IA64] unwind: remove preprocesser noise, and correct comment

1 files changed, 19 insertions, 4 deletions

diff --git a/arch/ia64/kernel/unwind.c b/arch/ia64/kernel/unwind.c
index b6c0e63a0bf6..fed6afa2e8a9 100644
--- a/arch/ia64/kernel/unwind.c
+++ b/arch/ia64/kernel/unwind.c
@@ -1204,10 +1204,10 @@ desc_spill_sprel_p (unsigned char qp, unw_word t, unsigned char abreg, unw_word
 static inline unw_hash_index_t
 hash (unsigned long ip)
 {
-#	define hashmagic	0x9e3779b97f4a7c16UL	/* based on (sqrt(5)/2-1)*2^64 */
+	/* magic number = ((sqrt(5)-1)/2)*2^64 */
+	static const unsigned long hashmagic = 0x9e3779b97f4a7c16UL;
 
-	return (ip >> 4)*hashmagic >> (64 - UNW_LOG_HASH_SIZE);
-#undef hashmagic
+	return (ip >> 4) * hashmagic >> (64 - UNW_LOG_HASH_SIZE);
 }
 
 static inline long
@@ -1531,7 +1531,7 @@ build_script (struct unw_frame_info *info)
 	struct unw_labeled_state *ls, *next;
 	unsigned long ip = info->ip;
 	struct unw_state_record sr;
-	struct unw_table *table;
+	struct unw_table *table, *prev;
 	struct unw_reg_info *r;
 	struct unw_insn insn;
 	u8 *dp, *desc_end;
@@ -1560,11 +1560,26 @@ build_script (struct unw_frame_info *info)
 
 	STAT(parse_start = ia64_get_itc());
 
+	prev = NULL;
 	for (table = unw.tables; table; table = table->next) {
 		if (ip >= table->start && ip < table->end) {
+			/*
+			 * Leave the kernel unwind table at the very front,
+			 * lest moving it breaks some assumption elsewhere.
+			 * Otherwise, move the matching table to the second
+			 * position in the list so that traversals can benefit
+			 * from commonality in backtrace paths.
+			 */
+			if (prev && prev != unw.tables) {
+				/* unw is safe - we're already spinlocked */
+				prev->next = table->next;
+				table->next = unw.tables->next;
+				unw.tables->next = table;
+			}
 			e = lookup(table, ip - table->segment_base);
 			break;
 		}
+		prev = table;
 	}
 	if (!e) {
 		/* no info, return default unwinder (leaf proc, no mem stack, no saved regs)  */