hw_breakpoints: Allow arch-specific cleanup before breakpoint unregistration
Certain architectures (such as PowerPC) have a need to clean up data
structures before a breakpoint is unregistered. This introduces an
arch-specific hook in release_bp_slot() along with a weak definition
in the form of a stub function.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 7a56b22..71ed3ce 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -242,6 +242,17 @@
}
/*
+ * Function to perform processor-specific cleanup during unregistration
+ */
+__weak void arch_unregister_hw_breakpoint(struct perf_event *bp)
+{
+ /*
+ * A weak stub function here for those archs that don't define
+ * it inside arch/.../kernel/hw_breakpoint.c
+ */
+}
+
+/*
* Contraints to check before allowing this new breakpoint counter:
*
* == Non-pinned counter == (Considered as pinned for now)
@@ -339,6 +350,7 @@
{
mutex_lock(&nr_bp_mutex);
+ arch_unregister_hw_breakpoint(bp);
__release_bp_slot(bp);
mutex_unlock(&nr_bp_mutex);