[PATCH 1/3] x86/intel_rdt: Move special case code for Haswell to a quirk function

From: Luck, Tony
Date: Thu Aug 24 2017 - 12:31:22 EST


From: Tony Luck <tony.luck@xxxxxxxxx>

No functional change, but lay the ground work for other per-model
quirks.

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
---
arch/x86/kernel/cpu/intel_rdt.c | 52 ++++++++++++++++++++++-------------------
1 file changed, 28 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index 6935c8ecad7f..25514cd454b3 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -172,34 +172,28 @@ static unsigned int cbm_idx(struct rdt_resource *r, unsigned int closid)
* is always 20 on hsw server parts. The minimum cache bitmask length
* allowed for HSW server is always 2 bits. Hardcode all of them.
*/
-static inline bool cache_alloc_hsw_probe(void)
+static inline void cache_alloc_hsw_probe(void)
{
- if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
- boot_cpu_data.x86 == 6 &&
- boot_cpu_data.x86_model == INTEL_FAM6_HASWELL_X) {
- struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3];
- u32 l, h, max_cbm = BIT_MASK(20) - 1;
+ struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3];
+ u32 l, h, max_cbm = BIT_MASK(20) - 1;

- if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0))
- return false;
- rdmsr(IA32_L3_CBM_BASE, l, h);
-
- /* If all the bits were set in MSR, return success */
- if (l != max_cbm)
- return false;
+ if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0))
+ return;
+ rdmsr(IA32_L3_CBM_BASE, l, h);

- r->num_closid = 4;
- r->default_ctrl = max_cbm;
- r->cache.cbm_len = 20;
- r->cache.shareable_bits = 0xc0000;
- r->cache.min_cbm_bits = 2;
- r->alloc_capable = true;
- r->alloc_enabled = true;
+ /* If all the bits were set in MSR, return success */
+ if (l != max_cbm)
+ return;

- return true;
- }
+ r->num_closid = 4;
+ r->default_ctrl = max_cbm;
+ r->cache.cbm_len = 20;
+ r->cache.shareable_bits = 0xc0000;
+ r->cache.min_cbm_bits = 2;
+ r->alloc_capable = true;
+ r->alloc_enabled = true;

- return false;
+ rdt_alloc_capable = true;
}

/*
@@ -647,7 +641,7 @@ static __init bool get_rdt_alloc_resources(void)
{
bool ret = false;

- if (cache_alloc_hsw_probe())
+ if (rdt_alloc_capable)
return true;

if (!boot_cpu_has(X86_FEATURE_RDT_A))
@@ -689,8 +683,18 @@ static __init bool get_rdt_mon_resources(void)
return !rdt_get_mon_l3_config(&rdt_resources_all[RDT_RESOURCE_L3]);
}

+static __init void rdt_quirks(void)
+{
+ switch (boot_cpu_data.x86_model) {
+ case INTEL_FAM6_HASWELL_X:
+ cache_alloc_hsw_probe();
+ break;
+ }
+}
+
static __init bool get_rdt_resources(void)
{
+ rdt_quirks();
rdt_alloc_capable = get_rdt_alloc_resources();
rdt_mon_capable = get_rdt_mon_resources();

--
2.11.0