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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-changelog] [xen master] x86: implement set value flow for MBA
commit b0e59e9eaa568580ff067a25fe4f0c333e6f6e60
Author: Yi Sun <yi.y.sun@xxxxxxxxxxxxxxx>
AuthorDate: Tue Dec 19 02:49:00 2017 +0100
Commit: Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Wed Dec 20 10:02:03 2017 +0100
x86: implement set value flow for MBA
This patch implements set value flow for MBA including its callback
function and domctl interface.
Signed-off-by: Yi Sun <yi.y.sun@xxxxxxxxxxxxxxx>
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
---
xen/arch/x86/domctl.c | 6 ++++++
xen/arch/x86/psr.c | 46 +++++++++++++++++++++++++++++++++++++++++----
xen/include/public/domctl.h | 1 +
3 files changed, 49 insertions(+), 4 deletions(-)
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index 75e5e35..36ab235 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -1505,6 +1505,12 @@ long arch_do_domctl(
PSR_TYPE_L2_CBM);
break;
+ case XEN_DOMCTL_PSR_SET_MBA_THRTL:
+ ret = psr_set_val(d, domctl->u.psr_alloc.target,
+ domctl->u.psr_alloc.data,
+ PSR_TYPE_MBA_THRTL);
+ break;
+
#define domctl_psr_get_val(d, domctl, type, copyback) ({ \
uint32_t v_; \
int r_ = psr_get_val((d), (domctl)->u.psr_alloc.target, \
diff --git a/xen/arch/x86/psr.c b/xen/arch/x86/psr.c
index a4901d8..0ba8ef8 100644
--- a/xen/arch/x86/psr.c
+++ b/xen/arch/x86/psr.c
@@ -138,6 +138,12 @@ static const struct feat_props {
/* write_msr is used to write out feature MSR register. */
void (*write_msr)(unsigned int cos, uint32_t val, enum psr_type type);
+
+ /*
+ * sanitize is used to check if input val fulfills SDM requirement.
+ * And change it to valid value if SDM allows.
+ */
+ bool (*sanitize)(const struct feat_node *feat, uint32_t *val);
} *feat_props[FEAT_TYPE_NUM];
/*
@@ -274,11 +280,14 @@ static enum psr_feat_type psr_type_to_feat_type(enum
psr_type type)
return feat_type;
}
-static bool psr_check_cbm(unsigned int cbm_len, unsigned long cbm)
+/* Implementation of allocation features' functions. */
+static bool cat_check_cbm(const struct feat_node *feat, uint32_t *val)
{
unsigned int first_bit, zero_bit;
+ unsigned int cbm_len = feat->cat.cbm_len;
+ unsigned long cbm = *val;
- /* Set bits should only in the range of [0, cbm_len]. */
+ /* Set bits should only in the range of [0, cbm_len). */
if ( cbm & (~0ul << cbm_len) )
return false;
@@ -297,7 +306,6 @@ static bool psr_check_cbm(unsigned int cbm_len, unsigned
long cbm)
return true;
}
-/* Implementation of allocation features' functions. */
static bool cat_init_feature(const struct cpuid_leaf *regs,
struct feat_node *feat,
struct psr_socket_info *info,
@@ -434,6 +442,7 @@ static const struct feat_props l3_cat_props = {
.alt_type = PSR_TYPE_UNKNOWN,
.get_feat_info = cat_get_feat_info,
.write_msr = l3_cat_write_msr,
+ .sanitize = cat_check_cbm,
};
/* L3 CDP props */
@@ -464,6 +473,7 @@ static const struct feat_props l3_cdp_props = {
.alt_type = PSR_TYPE_L3_CBM,
.get_feat_info = l3_cdp_get_feat_info,
.write_msr = l3_cdp_write_msr,
+ .sanitize = cat_check_cbm,
};
/* L2 CAT props */
@@ -479,6 +489,7 @@ static const struct feat_props l2_cat_props = {
.alt_type = PSR_TYPE_UNKNOWN,
.get_feat_info = cat_get_feat_info,
.write_msr = l2_cat_write_msr,
+ .sanitize = cat_check_cbm,
};
/* MBA props */
@@ -499,6 +510,32 @@ static bool mba_get_feat_info(const struct feat_node *feat,
static void mba_write_msr(unsigned int cos, uint32_t val,
enum psr_type type)
{
+ wrmsrl(MSR_IA32_PSR_MBA_MASK(cos), val);
+}
+
+static bool mba_sanitize_thrtl(const struct feat_node *feat, uint32_t *thrtl)
+{
+ /*
+ * Per SDM (chapter "Memory Bandwidth Allocation Configuration"):
+ * 1. Linear mode: In the linear mode the input precision is defined
+ * as 100-(MBA_MAX). For instance, if the MBA_MAX value is 90, the
+ * input precision is 10%. Values not an even multiple of the
+ * precision (e.g., 12%) will be rounded down (e.g., to 10% delay
+ * applied).
+ * 2. Non-linear mode: Input delay values are powers-of-two from zero
+ * to the MBA_MAX value from CPUID. In this case any values not a
+ * power of two will be rounded down the next nearest power of two.
+ */
+ if ( feat->mba.linear )
+ *thrtl -= *thrtl % (100 - feat->mba.thrtl_max);
+ else
+ {
+ /* Not power of 2. */
+ if ( *thrtl & (*thrtl - 1) )
+ *thrtl = 1 << (fls(*thrtl) - 1);
+ }
+
+ return *thrtl <= feat->mba.thrtl_max;
}
static const struct feat_props mba_props = {
@@ -507,6 +544,7 @@ static const struct feat_props mba_props = {
.alt_type = PSR_TYPE_UNKNOWN,
.get_feat_info = mba_get_feat_info,
.write_msr = mba_write_msr,
+ .sanitize = mba_sanitize_thrtl,
};
static bool __init parse_psr_bool(const char *s, const char *delim,
@@ -972,7 +1010,7 @@ static int insert_val_into_array(uint32_t val[],
if ( array_len < props->cos_num )
return -ENOSPC;
- if ( !psr_check_cbm(feat->cat.cbm_len, new_val) )
+ if ( !props->sanitize(feat, &new_val) )
return -EINVAL;
/*
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 44cf0b5..6d5396f 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -1074,6 +1074,7 @@ struct xen_domctl_psr_alloc {
#define XEN_DOMCTL_PSR_GET_L3_DATA 5
#define XEN_DOMCTL_PSR_SET_L2_CBM 6
#define XEN_DOMCTL_PSR_GET_L2_CBM 7
+#define XEN_DOMCTL_PSR_SET_MBA_THRTL 8
#define XEN_DOMCTL_PSR_GET_MBA_THRTL 9
uint32_t cmd; /* IN: XEN_DOMCTL_PSR_* */
uint32_t target; /* IN */
--
generated by git-patchbot for /home/xen/git/xen.git#master
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