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>
This commit is contained in:
K.Prasad 2010-06-15 11:34:34 +05:30 committed by Paul Mackerras
parent 0016a4cf55
commit f7136c5150

View File

@ -241,6 +241,17 @@ toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type,
per_cpu(nr_cpu_bp_pinned[type], bp->cpu) -= weight;
}
/*
* 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:
*
@ -339,6 +350,7 @@ void release_bp_slot(struct perf_event *bp)
{
mutex_lock(&nr_bp_mutex);
arch_unregister_hw_breakpoint(bp);
__release_bp_slot(bp);
mutex_unlock(&nr_bp_mutex);