On Mon, Dec 10, 2018 at 10:03:40PM -0800, Dan Williams wrote: > I have a use case to detect the presence of a memory-side-cache early > at init time [1]. To me this means that hmat_init() needs to happen as > a part of acpi_numa_init(). Subsequently I think that also means that > the sysfs portion needs to be broken out to its own init path that can > probably run at module_init() priority. > > Perhaps we should split this patch set into two? The table parsing > with an in-kernel user is a bit easier to reason about and can go in > first. Towards that end can I steal / refllow patches 1 & 2 into the > memory randomization series? Other ideas how to handle this? > > [1]: https://lkml.org/lkml/2018/10/12/309 To that end, will something like the following work for you? This just needs to happen after patch 1. --- diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c index f5e09c39ff22..03ef3c8ba4ea 100644 --- a/drivers/acpi/numa.c +++ b/drivers/acpi/numa.c @@ -40,6 +40,8 @@ static int pxm_to_node_map[MAX_PXM_DOMAINS] static int node_to_pxm_map[MAX_NUMNODES] = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL }; +static unsigned long node_side_cached[BITS_TO_LONGS(MAX_PXM_DOMAINS)]; + unsigned char acpi_srat_revision __initdata; int acpi_numa __initdata; @@ -262,6 +264,7 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) u64 start, end; u32 hotpluggable; int node, pxm; + bool side_cached; if (srat_disabled()) goto out_err; @@ -308,6 +311,11 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) pr_warn("SRAT: Failed to mark hotplug range [mem %#010Lx-%#010Lx] in memblock\n", (unsigned long long)start, (unsigned long long)end - 1); + side_cached = test_bit(pxm, node_side_cached); + if (side_cached && memblock_mark_sidecached(start, ma->length)) + pr_warn("SRAT: Failed to mark side cached range [mem %#010Lx-%#010Lx] in memblock\n", + (unsigned long long)start, (unsigned long long)end - 1); + max_possible_pfn = max(max_possible_pfn, PFN_UP(end - 1)); return 0; @@ -411,6 +419,19 @@ acpi_parse_memory_affinity(union acpi_subtable_headers * header, return 0; } +static int __init +acpi_parse_cache(union acpi_subtable_headers *header, const unsigned long end) +{ + struct acpi_hmat_cache *cache = (void *)header; + u32 attrs; + + attrs = cache->cache_attributes; + if (((attrs & ACPI_HMAT_CACHE_ASSOCIATIVITY) >> 8) == + ACPI_HMAT_CA_DIRECT_MAPPED) + set_bit(cache->memory_PD, node_side_cached); + return 0; +} + static int __init acpi_parse_srat(struct acpi_table_header *table) { struct acpi_table_srat *srat = (struct acpi_table_srat *)table; @@ -422,6 +443,11 @@ static int __init acpi_parse_srat(struct acpi_table_header *table) return 0; } +static __init int acpi_parse_hmat(struct acpi_table_header *table) +{ + return 0; +} + static int __init acpi_table_parse_srat(enum acpi_srat_type id, acpi_tbl_entry_handler handler, unsigned int max_entries) @@ -460,6 +486,16 @@ int __init acpi_numa_init(void) sizeof(struct acpi_table_srat), srat_proc, ARRAY_SIZE(srat_proc), 0); + if (!acpi_table_parse(ACPI_SIG_HMAT, acpi_parse_hmat)) { + struct acpi_subtable_proc hmat_proc; + + memset(&hmat_proc, 0, sizeof(hmat_proc)); + hmat_proc.handler = acpi_parse_cache; + hmat_proc.id = ACPI_HMAT_TYPE_CACHE; + acpi_table_parse_entries_array(ACPI_SIG_HMAT, + sizeof(struct acpi_table_hmat), + &hmat_proc, 1, 0); + } cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, acpi_parse_memory_affinity, 0); } diff --git a/include/linux/memblock.h b/include/linux/memblock.h index aee299a6aa76..a24c918a4496 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -44,6 +44,7 @@ enum memblock_flags { MEMBLOCK_HOTPLUG = 0x1, /* hotpluggable region */ MEMBLOCK_MIRROR = 0x2, /* mirrored region */ MEMBLOCK_NOMAP = 0x4, /* don't add to kernel direct mapping */ + MEMBLOCK_SIDECACHED = 0x8, /* System side caches memory access */ }; /** @@ -130,6 +131,7 @@ int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size); int memblock_mark_mirror(phys_addr_t base, phys_addr_t size); int memblock_mark_nomap(phys_addr_t base, phys_addr_t size); int memblock_clear_nomap(phys_addr_t base, phys_addr_t size); +int memblock_mark_sidecached(phys_addr_t base, phys_addr_t size); enum memblock_flags choose_memblock_flags(void); unsigned long memblock_free_all(void); @@ -227,6 +229,11 @@ static inline bool memblock_is_nomap(struct memblock_region *m) return m->flags & MEMBLOCK_NOMAP; } +static inline bool memblock_is_sidecached(struct memblock_region *m) +{ + return m->flags & MEMBLOCK_SIDECACHED; +} + #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP int memblock_search_pfn_nid(unsigned long pfn, unsigned long *start_pfn, unsigned long *end_pfn); diff --git a/mm/memblock.c b/mm/memblock.c index 9a2d5ae81ae1..827b709afdcd 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -865,6 +865,11 @@ int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size) return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG); } +int __init_memblock memblock_mark_sidecached(phys_addr_t base, phys_addr_t size) +{ + return memblock_setclr_flag(base, size, 1, MEMBLOCK_SIDECACHED); +} + /** * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region. * @base: the base phys addr of the region --
