aboutsummaryrefslogtreecommitdiff
path: root/lib/percpu_counter.c
diff options
context:
space:
mode:
authorMichal Marek <mmarek@suse.cz>2010-10-28 00:15:57 +0200
committerMichal Marek <mmarek@suse.cz>2010-10-28 00:15:57 +0200
commitb74b953b998bcc2db91b694446f3a2619ec32de6 (patch)
tree6ce24caabd730f6ae9287ed0676ec32e6ff31e9d /lib/percpu_counter.c
parentabb438526201c6a79949ad45375c051b6681c253 (diff)
parentf6f94e2ab1b33f0082ac22d71f66385a60d8157f (diff)
Merge commit 'v2.6.36' into kbuild/misc
Update to be able to fix a recent change to scripts/basic/docproc.c (commit eda603f).
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();