ANDROID: vendor_hooks: add hook and OEM data for slab shrink

Some shrinker add lock in count_objects() may cause lock contention
issues and lead all task stall on slab shrink. Add vendor hook in
do_shrink_slab() for shrinker->count_objects() latency measuring.

Add 3 oem data in shrink_control struct. Two is for
shrinker->count_objects() and shrinker->scan_objects() latency
measuring, other one to store priority, some shrinker know the reclaimer
priority can control the memory reclaim more better.

Bug: 188684131

Change-Id: I80e9d90179bb52a99c54d9a067c6fcee835bb2ad
Signed-off-by: rongqianfeng <rongqianfeng@vivo.com>

drivers/android/vendor_hooks.c

@@ -240,6 +240,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_get_unmapped_area_include_reserved_zone)
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_alloc_pages_slowpath);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_show_mem);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_print_slabinfo_header);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_do_shrink_slab);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_cache_show);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_typec_tcpci_override_toggling);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_typec_tcpci_chk_contaminant);