[PATCH 4.4 076/113] ARC: Elide redundant setup of DMA callbacks

Greg Kroah-Hartman
2016-09-05T16:54:36Z

From: Vineet Gupta <vgupta@synopsys.com>

commit 45c3b08a117e2232fc8d7b9e849ead36386f4f96 upstream.

For resources shared by all cores such as SLC and IOC, only the master
core needs to do any setups / enabling / disabling etc.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/arc/mm/cache.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -914,6 +914,15 @@ void arc_cache_init(void)

printk(arc_cache_mumbojumbo(0, str, sizeof(str)));

+ /*
+ * Only master CPU needs to execute rest of function:
+ * - Assume SMP so all cores will have same cache config so
+ * any geomtry checks will be same for all
+ * - IOC setup / dma callbacks only need to be setup once
+ */
+ if (cpu)
+ return;
+
if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) {
struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;