x86-64, NUMA: Better explain numa_distance handling
Handling of out-of-bounds distances and allocation failure can use better documentation. Add it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Yinghai Lu <yinghai@kernel.org> Acked-by: David Rientjes <rientjes@google.com>
This commit is contained in:
parent
ce0033307f
commit
eb8c1e2c83
@ -392,11 +392,12 @@ void __init numa_reset_distance(void)
|
||||
{
|
||||
size_t size = numa_distance_cnt * numa_distance_cnt * sizeof(numa_distance[0]);
|
||||
|
||||
/* numa_distance could be 1LU marking allocation failure, test cnt */
|
||||
if (numa_distance_cnt)
|
||||
memblock_x86_free_range(__pa(numa_distance),
|
||||
__pa(numa_distance) + size);
|
||||
numa_distance_cnt = 0;
|
||||
numa_distance = NULL;
|
||||
numa_distance = NULL; /* enable table creation */
|
||||
}
|
||||
|
||||
static int __init numa_alloc_distance(void)
|
||||
@ -447,6 +448,14 @@ static int __init numa_alloc_distance(void)
|
||||
* Set the distance from node @from to @to to @distance. If distance table
|
||||
* doesn't exist, one which is large enough to accomodate all the currently
|
||||
* known nodes will be created.
|
||||
*
|
||||
* If such table cannot be allocated, a warning is printed and further
|
||||
* calls are ignored until the distance table is reset with
|
||||
* numa_reset_distance().
|
||||
*
|
||||
* If @from or @to is higher than the highest known node at the time of
|
||||
* table creation or @distance doesn't make sense, the call is ignored.
|
||||
* This is to allow simplification of specific NUMA config implementations.
|
||||
*/
|
||||
void __init numa_set_distance(int from, int to, int distance)
|
||||
{
|
||||
|
@ -379,7 +379,11 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
|
||||
if (emu_nid_to_phys[i] == NUMA_NO_NODE)
|
||||
emu_nid_to_phys[i] = 0;
|
||||
|
||||
/* transform distance table */
|
||||
/*
|
||||
* Transform distance table. numa_set_distance() ignores all
|
||||
* out-of-bound distances. Just call it for every possible node
|
||||
* combination.
|
||||
*/
|
||||
numa_reset_distance();
|
||||
for (i = 0; i < MAX_NUMNODES; i++) {
|
||||
for (j = 0; j < MAX_NUMNODES; j++) {
|
||||
|
Loading…
Reference in New Issue
Block a user