From 4a3bac4e3ac212c31edd8b124a1a2c7e8c1767ed Mon Sep 17 00:00:00 2001 From: Reza Arbab Date: Mon, 12 Dec 2016 16:42:52 -0800 Subject: [PATCH] powerpc/mm: allow memory hotplug into a memoryless node Patch series "enable movable nodes on non-x86 configs", v7. This patchset allows more configs to make use of movable nodes. When CONFIG_MOVABLE_NODE is selected, there are two ways to introduce such nodes into the system: 1. Discover movable nodes at boot. Currently this is only possible on x86, but we will enable configs supporting fdt to do the same. 2. Hotplug and online all of a node's memory using online_movable. This is already possible on any config supporting memory hotplug, not just x86, but the Kconfig doesn't say so. We will fix that. We'll also remove some cruft on power which would prevent (2). This patch (of 5): Remove the check which prevents us from hotplugging into an empty node. The original commit b226e4621245 ("[PATCH] powerpc: don't add memory to empty node/zone"), states that this was intended to be a temporary measure. It is a workaround for an oops which no longer occurs. Link: http://lkml.kernel.org/r/1479160961-25840-2-git-send-email-arbab@linux.vnet.ibm.com Signed-off-by: Reza Arbab Reviewed-by: Aneesh Kumar K.V Acked-by: Balbir Singh Acked-by: Michael Ellerman Cc: "Aneesh Kumar K.V" Cc: "H. Peter Anvin" Cc: Alistair Popple Cc: Benjamin Herrenschmidt Cc: Bharata B Rao Cc: Frank Rowand Cc: Ingo Molnar Cc: Nathan Fontenot Cc: Paul Mackerras Cc: Rob Herring Cc: Stewart Smith Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/powerpc/mm/numa.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index a51c188b81f3..0cb6bd8bfccf 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1085,7 +1085,7 @@ static int hot_add_node_scn_to_nid(unsigned long scn_addr) int hot_add_scn_to_nid(unsigned long scn_addr) { struct device_node *memory = NULL; - int nid, found = 0; + int nid; if (!numa_enabled || (min_common_depth < 0)) return first_online_node; @@ -1101,17 +1101,6 @@ int hot_add_scn_to_nid(unsigned long scn_addr) if (nid < 0 || !node_online(nid)) nid = first_online_node; - if (NODE_DATA(nid)->node_spanned_pages) - return nid; - - for_each_online_node(nid) { - if (NODE_DATA(nid)->node_spanned_pages) { - found = 1; - break; - } - } - - BUG_ON(!found); return nid; }