At 11/20/2012 02:22 PM, Jaegeuk Hanse Wrote: > On 11/01/2012 05:44 PM, Wen Congyang wrote: >> From: Yasuaki Ishimatsu <[email protected]> >> >> Currently __remove_section for SPARSEMEM_VMEMMAP does nothing. But >> even if >> we use SPARSEMEM_VMEMMAP, we can unregister the memory_section. >> >> So the patch add unregister_memory_section() into __remove_section(). > > Hi Yasuaki, > > In order to review this patch, I should dig sparse memory codes in > advance. But I have some confuse of codes. Why need encode/decode mem > map instead of set mem_map to ms->section_mem_map directly?
The memmap is aligned, and the low bits are zero. We store some information in these bits. So we need to encode/decode memmap here. Thanks Wen Congyang > > Regards, > Jaegeuk > >> >> CC: David Rientjes <[email protected]> >> CC: Jiang Liu <[email protected]> >> CC: Len Brown <[email protected]> >> CC: Christoph Lameter <[email protected]> >> Cc: Minchan Kim <[email protected]> >> CC: Andrew Morton <[email protected]> >> CC: KOSAKI Motohiro <[email protected]> >> CC: Wen Congyang <[email protected]> >> Signed-off-by: Yasuaki Ishimatsu <[email protected]> >> --- >> mm/memory_hotplug.c | 13 ++++++++----- >> 1 file changed, 8 insertions(+), 5 deletions(-) >> >> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >> index ca07433..66a79a7 100644 >> --- a/mm/memory_hotplug.c >> +++ b/mm/memory_hotplug.c >> @@ -286,11 +286,14 @@ static int __meminit __add_section(int nid, >> struct zone *zone, >> #ifdef CONFIG_SPARSEMEM_VMEMMAP >> static int __remove_section(struct zone *zone, struct mem_section *ms) >> { >> - /* >> - * XXX: Freeing memmap with vmemmap is not implement yet. >> - * This should be removed later. >> - */ >> - return -EBUSY; >> + int ret = -EINVAL; >> + >> + if (!valid_section(ms)) >> + return ret; >> + >> + ret = unregister_memory_section(ms); >> + >> + return ret; >> } >> #else >> static int __remove_section(struct zone *zone, struct mem_section *ms) > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
