Merge branch 'linus' into cont_syslog

[safe/jmp/linux-2.6] / kernel / hw_breakpoint.c

diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 974498b..7a56b22 100644 (file)
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -40,20 +40,12 @@
 #include <linux/percpu.h>
 #include <linux/sched.h>
 #include <linux/init.h>
+#include <linux/slab.h>
 #include <linux/cpu.h>
 #include <linux/smp.h>
 
 #include <linux/hw_breakpoint.h>
 
-enum bp_type_idx {
-       TYPE_INST       = 0,
-#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
-       TYPE_DATA       = 0,
-#else
-       TYPE_DATA       = 1,
-#endif
-       TYPE_MAX
-};
 
 /*
  * Constraints data
@@ -63,11 +55,15 @@ enum bp_type_idx {
 static DEFINE_PER_CPU(unsigned int, nr_cpu_bp_pinned[TYPE_MAX]);
 
 /* Number of pinned task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_task_bp_pinned[TYPE_MAX][HBP_NUM]);
+static DEFINE_PER_CPU(unsigned int *, nr_task_bp_pinned[TYPE_MAX]);
 
 /* Number of non-pinned cpu/task breakpoints in a cpu */
 static DEFINE_PER_CPU(unsigned int, nr_bp_flexible[TYPE_MAX]);
 
+static int nr_slots[TYPE_MAX];
+
+static int constraints_initialized;
+
 /* Gather the number of total pinned and un-pinned bp in a cpuset */
 struct bp_busy_slots {
        unsigned int pinned;
@@ -99,7 +95,7 @@ static unsigned int max_task_bp_pinned(int cpu, enum bp_type_idx type)
        int i;
        unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
 
-       for (i = HBP_NUM -1; i >= 0; i--) {
+       for (i = nr_slots[type] - 1; i >= 0; i--) {
                if (tsk_pinned[i] > 0)
                        return i + 1;
        }
@@ -292,6 +288,10 @@ static int __reserve_bp_slot(struct perf_event *bp)
        enum bp_type_idx type;
        int weight;
 
+       /* We couldn't initialize breakpoint constraints on boot */
+       if (!constraints_initialized)
+               return -ENOMEM;
+
        /* Basic checks */
        if (bp->attr.bp_type == HW_BREAKPOINT_EMPTY ||
            bp->attr.bp_type == HW_BREAKPOINT_INVALID)
@@ -304,7 +304,7 @@ static int __reserve_bp_slot(struct perf_event *bp)
        fetch_this_slot(&slots, weight);
 
        /* Flexible counters need to keep at least one slot */
-       if (slots.pinned + (!!slots.flexible) > HBP_NUM)
+       if (slots.pinned + (!!slots.flexible) > nr_slots[type])
                return -ENOSPC;
 
        toggle_bp_slot(bp, true, type, weight);
@@ -551,7 +551,36 @@ static struct notifier_block hw_breakpoint_exceptions_nb = {
 
 static int __init init_hw_breakpoint(void)
 {
+       unsigned int **task_bp_pinned;
+       int cpu, err_cpu;
+       int i;
+
+       for (i = 0; i < TYPE_MAX; i++)
+               nr_slots[i] = hw_breakpoint_slots(i);
+
+       for_each_possible_cpu(cpu) {
+               for (i = 0; i < TYPE_MAX; i++) {
+                       task_bp_pinned = &per_cpu(nr_task_bp_pinned[i], cpu);
+                       *task_bp_pinned = kzalloc(sizeof(int) * nr_slots[i],
+                                                 GFP_KERNEL);
+                       if (!*task_bp_pinned)
+                               goto err_alloc;
+               }
+       }
+
+       constraints_initialized = 1;
+
        return register_die_notifier(&hw_breakpoint_exceptions_nb);
+
+ err_alloc:
+       for_each_possible_cpu(err_cpu) {
+               if (err_cpu == cpu)
+                       break;
+               for (i = 0; i < TYPE_MAX; i++)
+                       kfree(per_cpu(nr_task_bp_pinned[i], cpu));
+       }
+
+       return -ENOMEM;
 }
 core_initcall(init_hw_breakpoint);