diff options
author | Mike Rapoport <[email protected]> | 2021-06-28 19:42:43 -0700 |
---|---|---|
committer | Linus Torvalds <[email protected]> | 2021-06-29 10:53:55 -0700 |
commit | e7793e53901b31a06db534679e77c0cdeab260a2 (patch) | |
tree | 40a3312efc91ff8fb4c093f5d48d2e0079a6b6be | |
parent | fdb7d9b7acd02f573ae4fc0c7772f6b5c6b1bad0 (diff) |
arc: update comment about HIGHMEM implementation
Arc does not use DISCONTIGMEM to implement high memory, update the comment
describing how high memory works to reflect this.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Rapoport <[email protected]>
Acked-by: Vineet Gupta <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Richard Henderson <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
-rw-r--r-- | arch/arc/mm/init.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index e2ed355438c9..397a201adfe3 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -139,16 +139,13 @@ void __init setup_arch_memory(void) #ifdef CONFIG_HIGHMEM /* - * Populate a new node with highmem - * * On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based) - * than addresses in normal ala low memory (0x8000_0000 based). + * than addresses in normal aka low memory (0x8000_0000 based). * Even with PAE, the huge peripheral space hole would waste a lot of - * mem with single mem_map[]. This warrants a mem_map per region design. - * Thus HIGHMEM on ARC is imlemented with DISCONTIGMEM. - * - * DISCONTIGMEM in turns requires multiple nodes. node 0 above is - * populated with normal memory zone while node 1 only has highmem + * mem with single contiguous mem_map[]. + * Thus when HIGHMEM on ARC is enabled the memory map corresponding + * to the hole is freed and ARC specific version of pfn_valid() + * handles the hole in the memory map. */ #ifdef CONFIG_DISCONTIGMEM node_set_online(1); |