6.6-stable review patch. If anyone has any objections, please let me know.
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From: Alison Schofield alison.schofield@intel.com
[ Upstream commit 8f1004679987302b155f14b966ca6d4335814fcb ]
Commit fd49f99c1809 ("ACPI: NUMA: Add a node and memblk for each CFMWS not in SRAT") did not account for the case where the BIOS only partially describes a CFMWS Window in the SRAT. That means the omitted address ranges, of a partially described CFMWS Window, do not get assigned to a NUMA node.
Replace the call to phys_to_target_node() with numa_add_memblks(). Numa_add_memblks() searches an HPA range for existing memblk(s) and extends those memblk(s) to fill the entire CFMWS Window.
Extending the existing memblks is a simple strategy that reuses SRAT defined proximity domains from part of a window to fill out the entire window, based on the knowledge* that all of a CFMWS window is of a similar performance class.
*Note that this heuristic will evolve when CFMWS Windows present a wider range of characteristics. The extension of the proximity domain, implemented here, is likely a step in developing a more sophisticated performance profile in the future.
There is no change in behavior when the SRAT does not describe the CFMWS Window at all. In that case, a new NUMA node with a single memblk covering the entire CFMWS Window is created.
Fixes: fd49f99c1809 ("ACPI: NUMA: Add a node and memblk for each CFMWS not in SRAT") Reported-by: Derick Marks derick.w.marks@intel.com Suggested-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Alison Schofield alison.schofield@intel.com Signed-off-by: Dave Hansen dave.hansen@linux.intel.com Reviewed-by: Dan Williams dan.j.williams@intel.com Tested-by: Derick Marks derick.w.marks@intel.com Link: https://lore.kernel.org/all/eaa0b7cffb0951a126223eef3cbe7b55b8300ad9.1689018... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/numa/srat.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c index 1f4fc5f8a819d..12f330b0eac01 100644 --- a/drivers/acpi/numa/srat.c +++ b/drivers/acpi/numa/srat.c @@ -310,11 +310,16 @@ static int __init acpi_parse_cfmws(union acpi_subtable_headers *header, start = cfmws->base_hpa; end = cfmws->base_hpa + cfmws->window_size;
- /* Skip if the SRAT already described the NUMA details for this HPA */ - node = phys_to_target_node(start); - if (node != NUMA_NO_NODE) + /* + * The SRAT may have already described NUMA details for all, + * or a portion of, this CFMWS HPA range. Extend the memblks + * found for any portion of the window to cover the entire + * window. + */ + if (!numa_fill_memblks(start, end)) return 0;
+ /* No SRAT description. Create a new node. */ node = acpi_map_pxm_to_node(*fake_pxm);
if (node == NUMA_NO_NODE) {