@@ -13,16 +13,118 @@
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
-#include <xen/init.h>
#include <xen/cpu.h>
#include <xen/err.h>
+#include <xen/init.h>
#include <xen/sched.h>
#include <asm/psr.h>
+/*
+ * Terminology:
+ * - CAT Cache Allocation Technology
+ * - CBM Capacity BitMasks
+ * - CDP Code and Data Prioritization
+ * - CMT Cache Monitoring Technology
+ * - COS/CLOS Class of Service. Also mean COS registers.
+ * - COS_MAX Max number of COS for the feature (minus 1)
+ * - MSRs Machine Specific Registers
+ * - PSR Intel Platform Shared Resource
+ */
+
#define PSR_CMT (1<<0)
#define PSR_CAT (1<<1)
#define PSR_CDP (1<<2)
+#define CAT_CBM_LEN_MASK 0x1f
+#define CAT_COS_MAX_MASK 0xffff
+
+/*
+ * Per SDM chapter 'Cache Allocation Technology: Cache Mask Configuration',
+ * the MSRs ranging from 0C90H through 0D0FH (inclusive), enables support for
+ * up to 128 L3 CAT Classes of Service. The COS_ID=[0,127].
+ *
+ * The MSRs ranging from 0D10H through 0D4FH (inclusive), enables support for
+ * up to 64 L2 CAT COS. The COS_ID=[0,63].
+ *
+ * So, the maximum COS register count of one feature is 128.
+ */
+#define MAX_COS_REG_CNT 128
+
+/*
+ * Every PSR feature uses some COS registers for each COS ID, e.g. CDP uses 2
+ * COS registers (DATA and CODE) for one COS ID, but CAT uses 1 COS register.
+ * We use below macro as the max number of COS registers used by all features.
+ * So far, it is 2 which means CDP's COS registers number.
+ */
+#define MAX_COS_NUM 2
+
+enum psr_feat_type {
+ FEAT_TYPE_L3_CAT,
+ FEAT_TYPE_NUM,
+};
+
+/*
+ * This structure represents one feature.
+ * cos_max - The max COS registers number got through CPUID.
+ * cbm_len - The length of CBM got through CPUID.
+ * cos_reg_val - Array to store the values of COS registers. One entry stores
+ * the value of one COS register.
+ * For L3 CAT and L2 CAT, one entry corresponds to one COS_ID.
+ * For CDP, two entries correspond to one COS_ID. E.g.
+ * COS_ID=0 corresponds to cos_reg_val[0] (Data) and
+ * cos_reg_val[1] (Code).
+ */
+struct feat_node {
+ /* cos_max and cbm_len are common values for all features so far. */
+ unsigned int cos_max;
+ unsigned int cbm_len;
+ uint32_t cos_reg_val[MAX_COS_REG_CNT];
+};
+
+/*
+ * This structure defines feature specific values, e.g. cos_num.
+ *
+ * Array 'feat_props' is defined to save every feature's properties. We use
+ * 'enum psr_feat_type' as index.
+ */
+static const struct feat_props {
+ /*
+ * cos_num - COS registers number that feature uses for one COS ID.
+ * It is defined in SDM.
+ */
+ unsigned int cos_num;
+
+ /*
+ * An array to save all 'enum cbm_type' values of the feature. It is
+ * used with cos_num together to get/write a feature's COS registers
+ * values one by one.
+ */
+ enum cbm_type type[MAX_COS_NUM];
+
+ /*
+ * alt_type is 'alternative type'. When this 'alt_type' is input, the
+ * feature does some special operations.
+ */
+ enum cbm_type alt_type;
+} *feat_props[FEAT_TYPE_NUM];
+
+/*
+ * PSR features are managed per socket. Below structure defines the members
+ * used to manage these features.
+ * feat_init - Indicate if features on a socket have been initialized.
+ * features - A feature node array used to manage all features enabled.
+ * ref_lock - A lock to protect cos_ref.
+ * cos_ref - A reference count array to record how many domains are using the
+ * COS ID. Every entry of cos_ref corresponds to one COS ID.
+ */
+struct psr_socket_info {
+ bool feat_init;
+ /* Feature array's index is 'enum psr_feat_type' which is same as 'props' */
+ struct feat_node *features[FEAT_TYPE_NUM];
+ spinlock_t ref_lock;
+ unsigned int cos_ref[MAX_COS_REG_CNT];
+};
+
struct psr_assoc {
uint64_t val;
uint64_t cos_mask;
@@ -30,11 +132,105 @@ struct psr_assoc {
struct psr_cmt *__read_mostly psr_cmt;
+static struct psr_socket_info *__read_mostly socket_info;
+
static unsigned int opt_psr;
static unsigned int __initdata opt_rmid_max = 255;
+static unsigned int __read_mostly opt_cos_max = MAX_COS_REG_CNT;
static uint64_t rmid_mask;
static DEFINE_PER_CPU(struct psr_assoc, psr_assoc);
+/*
+ * Declare global feature node for every feature to facilitate the feature
+ * array creation. It is used to transiently store a spare node.
+ */
+static struct feat_node *feat_l3;
+
+/* Common functions */
+#define cat_default_val(len) (0xffffffff >> (32 - (len)))
+
+/*
+ * Use this function to check if any allocation feature has been enabled
+ * in cmdline.
+ */
+static bool psr_alloc_feat_enabled(void)
+{
+ return !!socket_info;
+}
+
+static void free_socket_resources(unsigned int socket)
+{
+ unsigned int i;
+ struct psr_socket_info *info = socket_info + socket;
+
+ if ( !info )
+ return;
+
+ /*
+ * Free resources of features. The global feature object, e.g. feat_l3,
+ * may not be freed here if it is not added into array. It is simply being
+ * kept until the next CPU online attempt.
+ */
+ for ( i = 0; i < ARRAY_SIZE(info->features); i++ )
+ {
+ xfree(info->features[i]);
+ info->features[i] = NULL;
+ }
+
+ info->feat_init = false;
+
+ memset(info->cos_ref, 0, MAX_COS_REG_CNT * sizeof(unsigned int));
+}
+
+/* CAT common functions implementation. */
+static int cat_init_feature(const struct cpuid_leaf *regs,
+ struct feat_node *feat,
+ struct psr_socket_info *info,
+ enum psr_feat_type type)
+{
+ /* No valid value so do not enable feature. */
+ if ( !regs->a || !regs->d )
+ return -ENOENT;
+
+ feat->cbm_len = (regs->a & CAT_CBM_LEN_MASK) + 1;
+ feat->cos_max = min(opt_cos_max, regs->d & CAT_COS_MAX_MASK);
+
+ switch ( type )
+ {
+ case FEAT_TYPE_L3_CAT:
+ if ( feat->cos_max < 1 )
+ return -ENOENT;
+
+ /* We reserve cos=0 as default cbm (all bits within cbm_len are 1). */
+ feat->cos_reg_val[0] = cat_default_val(feat->cbm_len);
+
+ wrmsrl(MSR_IA32_PSR_L3_MASK(0), cat_default_val(feat->cbm_len));
+
+ break;
+
+ default:
+ return -ENOENT;
+ }
+
+ /* Add this feature into array. */
+ info->features[type] = feat;
+
+ if ( !opt_cpu_info )
+ return 0;
+
+ printk(XENLOG_INFO "CAT: enabled on socket %u, cos_max:%u, cbm_len:%u\n",
+ cpu_to_socket(smp_processor_id()), feat->cos_max, feat->cbm_len);
+
+ return 0;
+}
+
+/* L3 CAT props */
+static const struct feat_props l3_cat_props = {
+ .cos_num = 1,
+ .type[0] = PSR_CBM_TYPE_L3,
+ .alt_type = PSR_CBM_TYPE_UNKNOWN,
+};
+
static void __init parse_psr_bool(char *s, char *value, char *feature,
unsigned int mask)
{
@@ -74,6 +270,9 @@ static void __init parse_psr_param(char *s)
if ( val_str && !strcmp(s, "rmid_max") )
opt_rmid_max = simple_strtoul(val_str, NULL, 0);
+ if ( val_str && !strcmp(s, "cos_max") )
+ opt_cos_max = simple_strtoul(val_str, NULL, 0);
+
s = ss + 1;
} while ( ss );
}
@@ -229,19 +428,98 @@ void psr_domain_free(struct domain *d)
psr_free_rmid(d);
}
-static int psr_cpu_prepare(unsigned int cpu)
+static void __init init_psr(void)
{
+ if ( opt_cos_max < 1 )
+ {
+ printk(XENLOG_INFO "CAT: disabled, cos_max is too small\n");
+ return;
+ }
+
+ socket_info = xzalloc_array(struct psr_socket_info, nr_sockets);
+
+ if ( !socket_info )
+ {
+ printk(XENLOG_WARNING "Failed to alloc socket_info!\n");
+ return;
+ }
+}
+
+static void __init psr_free(void)
+{
+ xfree(socket_info);
+ socket_info = NULL;
+}
+
+static int psr_cpu_prepare(void)
+{
+ if ( !psr_alloc_feat_enabled() )
+ return 0;
+
+ /* Malloc memory for the global feature node here. */
+ if ( feat_l3 == NULL &&
+ (feat_l3 = xzalloc(struct feat_node)) == NULL )
+ return -ENOMEM;
+
return 0;
}
static void psr_cpu_init(void)
{
+ struct psr_socket_info *info;
+ unsigned int socket, cpu = smp_processor_id();
+ struct feat_node *feat;
+ struct cpuid_leaf regs;
+
+ if ( !psr_alloc_feat_enabled() || !boot_cpu_has(X86_FEATURE_PQE) )
+ goto assoc_init;
+
+ if ( boot_cpu_data.cpuid_level < PSR_CPUID_LEVEL_CAT )
+ {
+ setup_clear_cpu_cap(X86_FEATURE_PQE);
+ goto assoc_init;
+ }
+
+ socket = cpu_to_socket(cpu);
+ info = socket_info + socket;
+ if ( info->feat_init )
+ goto assoc_init;
+
+ spin_lock_init(&info->ref_lock);
+
+ cpuid_count_leaf(PSR_CPUID_LEVEL_CAT, 0, ®s);
+ if ( regs.b & PSR_RESOURCE_TYPE_L3 )
+ {
+ cpuid_count_leaf(PSR_CPUID_LEVEL_CAT, 1, ®s);
+
+ feat = feat_l3;
+ feat_l3 = NULL;
+
+ if ( !cat_init_feature(®s, feat, info, FEAT_TYPE_L3_CAT) )
+ feat_props[FEAT_TYPE_L3_CAT] = &l3_cat_props;
+ else
+ feat_l3 = feat;
+ }
+
+ info->feat_init = true;
+
+ assoc_init:
psr_assoc_init();
}
static void psr_cpu_fini(unsigned int cpu)
{
- return;
+ unsigned int socket = cpu_to_socket(cpu);
+
+ if ( !psr_alloc_feat_enabled() )
+ return;
+
+ /*
+ * We only free when we are the last CPU in the socket. The socket_cpumask
+ * is cleared prior to this notification code by remove_siblinginfo().
+ */
+ if ( socket_cpumask[socket] && cpumask_empty(socket_cpumask[socket]) )
+ free_socket_resources(socket);
}
static int cpu_callback(
@@ -253,7 +531,7 @@ static int cpu_callback(
switch ( action )
{
case CPU_UP_PREPARE:
- rc = psr_cpu_prepare(cpu);
+ rc = psr_cpu_prepare();
break;
case CPU_STARTING:
psr_cpu_init();
@@ -282,10 +560,14 @@ static int __init psr_presmp_init(void)
if ( (opt_psr & PSR_CMT) && opt_rmid_max )
init_psr_cmt(opt_rmid_max);
- psr_cpu_prepare(0);
+ if ( opt_psr & PSR_CAT )
+ init_psr();
+
+ if ( psr_cpu_prepare() )
+ psr_free();
psr_cpu_init();
- if ( psr_cmt_enabled() )
+ if ( psr_cmt_enabled() || psr_alloc_feat_enabled() )
register_cpu_notifier(&cpu_nfb);
return 0;
@@ -50,6 +50,7 @@ enum cbm_type {
PSR_CBM_TYPE_L3,
PSR_CBM_TYPE_L3_CODE,
PSR_CBM_TYPE_L3_DATA,
+ PSR_CBM_TYPE_UNKNOWN,
};
extern struct psr_cmt *psr_cmt;