| Message ID | 1452140425-16577-2-git-send-email-tangchen@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
Hello, On Thu, Jan 07, 2016 at 12:20:21PM +0800, Tang Chen wrote: > +static void __init init_memory_less_node(int nid) > { > + unsigned long zones_size[MAX_NR_ZONES] = {0}; > + unsigned long zholes_size[MAX_NR_ZONES] = {0}; It doesn't cause any functional difference but it's a bit weird to use {0} because it explicitly says to initialize the first element to 0 when the whole array needs to be cleared. Wouldnt { } make more sense? > diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h > index e23a9e7..9c4d4d5 100644 > --- a/include/linux/mmzone.h > +++ b/include/linux/mmzone.h > @@ -736,6 +736,7 @@ static inline bool is_dev_zone(const struct zone *zone) > > extern struct mutex zonelists_mutex; > void build_all_zonelists(pg_data_t *pgdat, struct zone *zone); > +void build_zonelists(pg_data_t *pgdat); This isn't used in this patch. Contamination? Thanks.
Hi tj, On 01/09/2016 02:28 AM, Tejun Heo wrote: > Hello, > > On Thu, Jan 07, 2016 at 12:20:21PM +0800, Tang Chen wrote: >> +static void __init init_memory_less_node(int nid) >> { >> + unsigned long zones_size[MAX_NR_ZONES] = {0}; >> + unsigned long zholes_size[MAX_NR_ZONES] = {0}; > It doesn't cause any functional difference but it's a bit weird to use > {0} because it explicitly says to initialize the first element to 0 > when the whole array needs to be cleared. Wouldnt { } make more sense? Yes. Will fix them. > >> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h >> index e23a9e7..9c4d4d5 100644 >> --- a/include/linux/mmzone.h >> +++ b/include/linux/mmzone.h >> @@ -736,6 +736,7 @@ static inline bool is_dev_zone(const struct zone *zone) >> >> extern struct mutex zonelists_mutex; >> void build_all_zonelists(pg_data_t *pgdat, struct zone *zone); >> +void build_zonelists(pg_data_t *pgdat); > This isn't used in this patch. Contamination? Sorry, I tried to build zone lists here. But it totally unnecessary and led to some problems. I forgot to remove them when I fixed the problems. Will remove them. Thx. > > Thanks. > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index c3b3f65..010edb4 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -704,22 +704,19 @@ void __init x86_numa_init(void) numa_init(dummy_numa_init); } -static __init int find_near_online_node(int node) +static void __init init_memory_less_node(int nid) { - int n, val; - int min_val = INT_MAX; - int best_node = -1; + unsigned long zones_size[MAX_NR_ZONES] = {0}; + unsigned long zholes_size[MAX_NR_ZONES] = {0}; - for_each_online_node(n) { - val = node_distance(node, n); + /* Allocate and initialize node data. Memory-less node is now online.*/ + alloc_node_data(nid); + free_area_init_node(nid, zones_size, 0, zholes_size); - if (val < min_val) { - min_val = val; - best_node = n; - } - } - - return best_node; + /* + * All zonelists will be built later in start_kernel() after per cpu + * areas are initialized. + */ } /* @@ -748,8 +745,10 @@ void __init init_cpu_to_node(void) if (node == NUMA_NO_NODE) continue; + if (!node_online(node)) - node = find_near_online_node(node); + init_memory_less_node(node); + numa_set_node(cpu, node); } } diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index e23a9e7..9c4d4d5 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -736,6 +736,7 @@ static inline bool is_dev_zone(const struct zone *zone) extern struct mutex zonelists_mutex; void build_all_zonelists(pg_data_t *pgdat, struct zone *zone); +void build_zonelists(pg_data_t *pgdat); void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx); bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, int classzone_idx, int alloc_flags); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 9d666df..15c0358 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4145,7 +4145,7 @@ static void set_zonelist_order(void) current_zonelist_order = user_zonelist_order; } -static void build_zonelists(pg_data_t *pgdat) +void build_zonelists(pg_data_t *pgdat) { int j, node, load; enum zone_type i;
For now, x86 does not support memory-less node. A node without memory will not be onlined, and the cpus on it will be mapped to the other online nodes with memory in init_cpu_to_node(). The reason of doing this is to ensure each cpu has mapped to a node with memory, so that it will be able to allocate local memory for that cpu. But we don't have to do it in this way. In this series of patches, we are going to construct cpu <-> node mapping for all possible cpus at boot time, which is a 1-1 mapping. It means the cpu will be mapped to the node it belongs to, and will never be changed. If a node has only cpus but no memory, the cpus on it will be mapped to a memory-less node. And the memory-less node should be onlined. This patch allocate pgdats for all memory-less nodes and online them at boot time. As a result, when cpus on these memory-less nodes try to allocate memory from local node, it will automatically fall back to the proper zones in the zonelists. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> --- arch/x86/mm/numa.c | 27 +++++++++++++-------------- include/linux/mmzone.h | 1 + mm/page_alloc.c | 2 +- 3 files changed, 15 insertions(+), 15 deletions(-)