When registering a memory range a possibly overlapping memory block will be extended instead of creating a new one. If both ranges exactly overlap, the blocks remain unchanged and are just reused. The information if a memblock was extended is useful for diagnostics. Change return code of numa_fill_memblks() to also report if memblocks have been modified. Link: https://lore.kernel.org/all/ZiqnbD0CB9WUL1zu@aschofie-mobl2/T/#u Cc: Alison Schofield <alison.schofield@xxxxxxxxx> Signed-off-by: Robert Richter <rrichter@xxxxxxx> --- arch/x86/mm/numa.c | 33 ++++++++++++++++++--------------- drivers/acpi/numa/srat.c | 5 +++-- 2 files changed, 21 insertions(+), 17 deletions(-) diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index ce84ba86e69e..e34e96d57656 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -950,15 +950,16 @@ static struct numa_memblk *numa_memblk_list[NR_NODE_MEMBLKS] __initdata; * address range @start-@end * * RETURNS: - * 0 : Success - * NUMA_NO_MEMBLK : No memblks exist in address range @start-@end + * NUMA_NO_MEMBLK if no memblks exist in address range @start-@end, + * zero on success without blocks modified and non-zero positive + * values on success with blocks modified. */ int __init numa_fill_memblks(u64 start, u64 end) { struct numa_memblk **blk = &numa_memblk_list[0]; struct numa_meminfo *mi = &numa_meminfo; - int count = 0; + int count = 0, modified = 0; u64 prev_end; /* @@ -981,25 +982,27 @@ int __init numa_fill_memblks(u64 start, u64 end) /* Sort the list of pointers in memblk->start order */ sort(&blk[0], count, sizeof(blk[0]), cmp_memblk, NULL); - /* Make sure the first/last memblks include start/end */ - blk[0]->start = min(blk[0]->start, start); - blk[count - 1]->end = max(blk[count - 1]->end, end); - /* * Fill any gaps by tracking the previous memblks * end address and backfilling to it if needed. */ - prev_end = blk[0]->end; - for (int i = 1; i < count; i++) { + prev_end = start; + for (int i = 0; i < count; i++) { struct numa_memblk *curr = blk[i]; - if (prev_end >= curr->start) { - if (prev_end < curr->end) - prev_end = curr->end; - } else { + if (prev_end < curr->start) { curr->start = prev_end; - prev_end = curr->end; + modified = 1; } + + if (prev_end < curr->end) + prev_end = curr->end; } - return 0; + + if (blk[count - 1]->end < end) { + blk[count - 1]->end = end; + modified = 1; + } + + return modified; } diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c index e3f26e71637a..76b39a6d3aef 100644 --- a/drivers/acpi/numa/srat.c +++ b/drivers/acpi/numa/srat.c @@ -326,7 +326,7 @@ static int __init acpi_parse_cfmws(union acpi_subtable_headers *header, struct acpi_cedt_cfmws *cfmws; int *fake_pxm = arg; u64 start, end; - int node; + int node, modified; cfmws = (struct acpi_cedt_cfmws *)header; start = cfmws->base_hpa; @@ -338,7 +338,8 @@ static int __init acpi_parse_cfmws(union acpi_subtable_headers *header, * found for any portion of the window to cover the entire * window. */ - if (!numa_fill_memblks(start, end)) + modified = numa_fill_memblks(start, end); + if (modified != NUMA_NO_MEMBLK) return 0; /* No SRAT description. Create a new node. */ -- 2.39.2
