* 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.
+ * dom_set - A bitmap to indicate which domain's cos id has been set.
*/
struct psr_socket_info {
bool feat_init;
struct feat_node *features[FEAT_TYPE_NUM];
spinlock_t ref_lock;
unsigned int cos_ref[MAX_COS_REG_CNT];
+ /* Every bit corresponds to a domain. Index is domain_id. */
+ DECLARE_BITMAP(dom_set, DOMID_IDLE + 1);
};
struct psr_assoc {
info->feat_init = false;
memset(info->cos_ref, 0, MAX_COS_REG_CNT * sizeof(unsigned int));
+
+ bitmap_zero(info->dom_set, DOMID_IDLE + 1);
}
static enum psr_feat_type psr_cbm_type_to_feat_type(enum cbm_type type)
if ( psr_cmt_enabled() )
psr_assoc_rmid(®, d->arch.psr_rmid);
- /* If domain's 'psr_cos_ids' is NULL, we set default value for it. */
+ /*
+ * If the domain is not set in 'dom_set' bitmap, that means the domain's
+ * cos id is not valid. So, we have to use default value (0) to set ASSOC
+ * register. Furthermore, if domain's 'psr_cos_ids' is NULL, we need
+ * default value for it too (for case that the domain's psr_cos_ids is not
+ * successfully allocated).
+ */
if ( psra->cos_mask )
- reg = psr_assoc_cos(reg,
- (d->arch.psr_cos_ids ?
- d->arch.psr_cos_ids[cpu_to_socket(smp_processor_id())] :
- 0),
- psra->cos_mask);
+ {
+ unsigned int socket = cpu_to_socket(smp_processor_id());
+ struct psr_socket_info *info = socket_info + socket;
+ unsigned int cos = 0;
+
+ if ( likely(test_bit(d->domain_id, info->dom_set)) &&
+ d->arch.psr_cos_ids )
+ cos = d->arch.psr_cos_ids[socket];
+
+ reg = psr_assoc_cos(reg, cos, psra->cos_mask);
+ }
if ( reg != psra->val )
{
return -ENOENT;
}
+ domain_lock(d);
+ if ( !test_and_set_bit(d->domain_id, socket_info[socket].dom_set) )
+ d->arch.psr_cos_ids[socket] = 0;
+
cos = d->arch.psr_cos_ids[socket];
+ domain_unlock(d);
+
/*
* If input cos exceeds current feature's cos_max, we should return its
* default value which is stored in cos 0. This case only happens
return -EINVAL;
}
-int psr_set_l3_cbm(struct domain *d, unsigned int socket,
- uint64_t cbm, enum cbm_type type)
+/* Set value functions */
+static unsigned int get_cos_num(void)
{
return 0;
}
-/* Called with domain lock held, no extra lock needed for 'psr_cos_ids' */
+static int gather_val_array(uint32_t val[],
+ unsigned int array_len,
+ const struct psr_socket_info *info,
+ unsigned int old_cos)
+{
+ return -EINVAL;
+}
+
+static int insert_val_into_array(uint32_t val[],
+ unsigned int array_len,
+ const struct psr_socket_info *info,
+ enum psr_feat_type feat_type,
+ enum cbm_type type,
+ uint32_t new_val)
+{
+ return -EINVAL;
+}
+
+static int find_cos(const uint32_t val[], unsigned int array_len,
+ enum psr_feat_type feat_type,
+ const struct psr_socket_info *info)
+{
+ return -ENOENT;
+}
+
+static int pick_avail_cos(const struct psr_socket_info *info,
+ const uint32_t val[], unsigned int array_len,
+ unsigned int old_cos,
+ enum psr_feat_type feat_type)
+{
+ return -ENOENT;
+}
+
+static int write_psr_msrs(unsigned int socket, unsigned int cos,
+ const uint32_t val[], unsigned int array_len,
+ enum psr_feat_type feat_type)
+{
+ return -ENOENT;
+}
+
+int psr_set_val(struct domain *d, unsigned int socket,
+ uint64_t new_val, enum cbm_type type)
+{
+ unsigned int old_cos, array_len;
+ int cos, ret;
+ unsigned int *ref;
+ uint32_t *val_array, val;
+ struct psr_socket_info *info = get_socket_info(socket);
+ enum psr_feat_type feat_type;
+
+ if ( IS_ERR(info) )
+ return PTR_ERR(info);
+
+ val = new_val;
+ if ( new_val != val )
+ return -EINVAL;
+
+ feat_type = psr_cbm_type_to_feat_type(type);
+ if ( feat_type >= ARRAY_SIZE(info->features) ||
+ !info->features[feat_type] )
+ return -ENOENT;
+
+ /*
+ * Step 0:
+ * old_cos means the COS ID current domain is using. By default, it is 0.
+ *
+ * For every COS ID, there is a reference count to record how many domains
+ * are using the COS register corresponding to this COS ID.
+ * - If ref[old_cos] is 0, that means this COS is not used by any domain.
+ * - If ref[old_cos] is 1, that means this COS is only used by current
+ * domain.
+ * - If ref[old_cos] is more than 1, that mean multiple domains are using
+ * this COS.
+ */
+ domain_lock(d);
+ if ( !test_and_set_bit(d->domain_id, info->dom_set) )
+ d->arch.psr_cos_ids[socket] = 0;
+
+ old_cos = d->arch.psr_cos_ids[socket];
+ domain_unlock(d);
+
+ ASSERT(old_cos < MAX_COS_REG_CNT);
+
+ ref = info->cos_ref;
+
+ /*
+ * Step 1:
+ * Gather a value array to store all features cos_reg_val[old_cos].
+ * And, set the input new val into array according to the feature's
+ * position in array.
+ */
+ array_len = get_cos_num();
+ val_array = xzalloc_array(uint32_t, array_len);
+ if ( !val_array )
+ return -ENOMEM;
+
+ if ( (ret = gather_val_array(val_array, array_len, info, old_cos)) != 0 )
+ goto free_array;
+
+ if ( (ret = insert_val_into_array(val_array, array_len, info,
+ feat_type, type, val)) != 0 )
+ goto free_array;
+
+ spin_lock(&info->ref_lock);
+
+ /*
+ * Step 2:
+ * Try to find if there is already a COS ID on which all features' values
+ * are same as the array. Then, we can reuse this COS ID.
+ */
+ cos = find_cos(val_array, array_len, feat_type, info);
+ if ( cos == old_cos )
+ {
+ ret = 0;
+ goto unlock_free_array;
+ }
+
+ /*
+ * Step 3:
+ * If fail to find, we need pick an available COS ID.
+ * In fact, only COS ID which ref is 1 or 0 can be picked for current
+ * domain. If old_cos is not 0 and its ref==1, that means only current
+ * domain is using this old_cos ID. So, this old_cos ID certainly can
+ * be reused by current domain. Ref==0 means there is no any domain
+ * using this COS ID. So it can be used for current domain too.
+ */
+ if ( cos < 0 )
+ {
+ cos = pick_avail_cos(info, val_array, array_len, old_cos, feat_type);
+ if ( cos < 0 )
+ {
+ ret = cos;
+ goto unlock_free_array;
+ }
+
+ /*
+ * Step 4:
+ * Write the feature's MSRs according to the COS ID.
+ */
+ ret = write_psr_msrs(socket, cos, val_array, array_len, feat_type);
+ if ( ret )
+ goto unlock_free_array;
+ }
+
+ /*
+ * Step 5:
+ * Find the COS ID (find_cos result is '>= 0' or an available COS ID is
+ * picked, then update ref according to COS ID.
+ */
+ ref[cos]++;
+ ASSERT(!cos || ref[cos]);
+ ASSERT(!old_cos || ref[old_cos]);
+ ref[old_cos]--;
+ spin_unlock(&info->ref_lock);
+
+ /*
+ * Step 6:
+ * Save the COS ID into current domain's psr_cos_ids[] so that we can know
+ * which COS the domain is using on the socket. One domain can only use
+ * one COS ID at same time on each socket.
+ */
+ domain_lock(d);
+ d->arch.psr_cos_ids[socket] = cos;
+ domain_unlock(d);
+
+ goto free_array;
+
+ unlock_free_array:
+ spin_unlock(&info->ref_lock);
+
+ free_array:
+ xfree(val_array);
+ return ret;
+}
+
static void psr_free_cos(struct domain *d)
{
+ unsigned int socket, cos;
+
+ ASSERT(socket_info);
+
+ if ( !d->arch.psr_cos_ids )
+ return;
+
+ /* Domain is destroyed so its cos_ref should be decreased. */
+ for ( socket = 0; socket < nr_sockets; socket++ )
+ {
+ struct psr_socket_info *info = socket_info + socket;
+
+ clear_bit(d->domain_id, info->dom_set);
+
+ /* cos 0 is default one which does not need be handled. */
+ cos = d->arch.psr_cos_ids[socket];
+ if ( cos == 0 )
+ continue;
+
+ spin_lock(&info->ref_lock);
+ ASSERT(info->cos_ref[cos]);
+ info->cos_ref[cos]--;
+ spin_unlock(&info->ref_lock);
+ }
+
xfree(d->arch.psr_cos_ids);
d->arch.psr_cos_ids = NULL;
}
projects / people / royger / xen.git / commitdiff