diff options
| author | Babu Moger <babu.moger@amd.com> | 2025-11-12 18:57:29 -0600 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2025-11-21 22:04:59 +0100 |
| commit | 7923ae7698cf9728501974d76d8ea712686281bc (patch) | |
| tree | cdc16590540510fbc2823b7865a03761f6e5f1de | |
| parent | 4d4840b1251acc194e4b59d9a5bfba23cd573ed3 (diff) | |
x86,fs/resctrl: Detect io_alloc feature
AMD's SDCIAE (SDCI Allocation Enforcement) PQE feature enables system software
to control the portions of L3 cache used for direct insertion of data from I/O
devices into the L3 cache.
Introduce a generic resctrl cache resource property "io_alloc_capable" as the
first part of the new "io_alloc" resctrl feature that will support AMD's
SDCIAE. Any architecture can set a cache resource as "io_alloc_capable" if
a portion of the cache can be allocated for I/O traffic.
Set the "io_alloc_capable" property for the L3 cache resource on x86 (AMD)
systems that support SDCIAE.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://patch.msgid.link/df85a9a6081674fd3ef6b4170920485512ce2ded.1762995456.git.babu.moger@amd.com
| -rw-r--r-- | arch/x86/kernel/cpu/resctrl/core.c | 7 | ||||
| -rw-r--r-- | include/linux/resctrl.h | 3 |
2 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 2b2935b3df8d..3792ab4819dc 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -274,6 +274,11 @@ static void rdt_get_cdp_config(int level) rdt_resources_all[level].r_resctrl.cdp_capable = true; } +static void rdt_set_io_alloc_capable(struct rdt_resource *r) +{ + r->cache.io_alloc_capable = true; +} + static void rdt_get_cdp_l3_config(void) { rdt_get_cdp_config(RDT_RESOURCE_L3); @@ -855,6 +860,8 @@ static __init bool get_rdt_alloc_resources(void) rdt_get_cache_alloc_cfg(1, r); if (rdt_cpu_has(X86_FEATURE_CDP_L3)) rdt_get_cdp_l3_config(); + if (rdt_cpu_has(X86_FEATURE_SDCIAE)) + rdt_set_io_alloc_capable(r); ret = true; } if (rdt_cpu_has(X86_FEATURE_CAT_L2)) { diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index a7d92718b653..533f240dbe21 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -206,6 +206,8 @@ struct rdt_mon_domain { * @arch_has_sparse_bitmasks: True if a bitmask like f00f is valid. * @arch_has_per_cpu_cfg: True if QOS_CFG register for this cache * level has CPU scope. + * @io_alloc_capable: True if portion of the cache can be configured + * for I/O traffic. */ struct resctrl_cache { unsigned int cbm_len; @@ -213,6 +215,7 @@ struct resctrl_cache { unsigned int shareable_bits; bool arch_has_sparse_bitmasks; bool arch_has_per_cpu_cfg; + bool io_alloc_capable; }; /** |