On 03/05/17 13:52, Rashmica Gupta wrote:
On 28/04/17 19:52, Anshuman Khandual wrote:
....
+static int check_memblock_online(struct memory_block *mem, void *arg)
+{
+ if (mem->state != MEM_ONLINE)
+ return -1;
+
+ return 0;
+}
+
+static int change_memblock_state(struct memory_block *mem, void *arg)
+{
+ unsigned long state = (unsigned long)arg;
+
+ mem->state = state;
+ return 0;
+}
+
+static bool memtrace_offline_pages(u32 nid, u64 start_pfn, u64
nr_pages)
+{
+ u64 end_pfn = start_pfn + nr_pages - 1;
+
+ if (walk_memory_range(start_pfn, end_pfn, NULL,
+ check_memblock_online))
+ return false;
+
+ walk_memory_range(start_pfn, end_pfn, (void *)MEM_GOING_OFFLINE,
+ change_memblock_state);
+
walk_memory_range() might be expensive, cant we just change the state
to MEM_GOING_OFFLINE while checking the state for MEM_ONLINE during
the first loop and bail out if any of the memblock is not in MEM_ONLINE
in the first place.
Good idea.
This is assuming that it's more likely that the state of memory will be
MEM_ONLINE rather than anything else (if the state isn't MEM_ONLINE we
will still have to do a second call of walk_memory_range() to revert the
state of any memory blocks that we changed). Seems like a reasonable
assumption to me, thoughts?
