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authorLen Brown <len.brown@intel.com>2010-08-15 01:06:31 -0400
committerLen Brown <len.brown@intel.com>2010-08-15 01:06:31 -0400
commit95ee46aa8698f2000647dfb362400fadbb5807cf (patch)
treee5a05c7297f997e191c73091934e42e3195c0e40 /lib/percpu_counter.c
parentcfa806f059801dbe7e435745eb2e187c8bfe1e7f (diff)
parent92fa5bd9a946b6e7aab6764e7312e4e3d9bed295 (diff)
Merge branch 'linus' into release
Conflicts: drivers/acpi/debug.c Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'lib/percpu_counter.c')
-rw-r--r--lib/percpu_counter.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index aeaa6d73444..ec9048e74f4 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -137,6 +137,33 @@ static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb,
return NOTIFY_OK;
}
+/*
+ * Compare counter against given value.
+ * Return 1 if greater, 0 if equal and -1 if less
+ */
+int percpu_counter_compare(struct percpu_counter *fbc, s64 rhs)
+{
+ s64 count;
+
+ count = percpu_counter_read(fbc);
+ /* Check to see if rough count will be sufficient for comparison */
+ if (abs(count - rhs) > (percpu_counter_batch*num_online_cpus())) {
+ if (count > rhs)
+ return 1;
+ else
+ return -1;
+ }
+ /* Need to use precise count */
+ count = percpu_counter_sum(fbc);
+ if (count > rhs)
+ return 1;
+ else if (count < rhs)
+ return -1;
+ else
+ return 0;
+}
+EXPORT_SYMBOL(percpu_counter_compare);
+
static int __init percpu_counter_startup(void)
{
compute_batch_value();