if (i == SC_ACK) {
count = dd->n_krcv_queues;
} else if (i == SC_KERNEL) {
- count = num_vls + 1 /* VL15 */;
+ count = (INIT_SC_PER_VL * num_vls) + 1 /* VL15 */;
} else if (count == SCC_PER_CPU) {
count = dd->num_rcv_contexts - dd->n_krcv_queues;
} else if (count < 0) {
spin_unlock(&dd->sc_lock);
}
+/*
+ * pio_select_send_context_vl() - select send context
+ * @dd: devdata
+ * @selector: a spreading factor
+ * @vl: this vl
+ *
+ * This function returns a send context based on the selector and a vl.
+ * The mapping fields are protected by RCU
+ */
+struct send_context *pio_select_send_context_vl(struct hfi1_devdata *dd,
+ u32 selector, u8 vl)
+{
+ struct pio_vl_map *m;
+ struct pio_map_elem *e;
+ struct send_context *rval;
+
+ /*
+ * NOTE This should only happen if SC->VL changed after the initial
+ * checks on the QP/AH
+ * Default will return VL0's send context below
+ */
+ if (unlikely(vl >= num_vls)) {
+ rval = NULL;
+ goto done;
+ }
+
+ rcu_read_lock();
+ m = rcu_dereference(dd->pio_map);
+ if (unlikely(!m)) {
+ rcu_read_unlock();
+ return dd->vld[0].sc;
+ }
+ e = m->map[vl & m->mask];
+ rval = e->ksc[selector & e->mask];
+ rcu_read_unlock();
+
+done:
+ rval = !rval ? dd->vld[0].sc : rval;
+ return rval;
+}
+
+/*
+ * pio_select_send_context_sc() - select send context
+ * @dd: devdata
+ * @selector: a spreading factor
+ * @sc5: the 5 bit sc
+ *
+ * This function returns an send context based on the selector and an sc
+ */
+struct send_context *pio_select_send_context_sc(struct hfi1_devdata *dd,
+ u32 selector, u8 sc5)
+{
+ u8 vl = sc_to_vlt(dd, sc5);
+
+ return pio_select_send_context_vl(dd, selector, vl);
+}
+
+/*
+ * Free the indicated map struct
+ */
+static void pio_map_free(struct pio_vl_map *m)
+{
+ int i;
+
+ for (i = 0; m && i < m->actual_vls; i++)
+ kfree(m->map[i]);
+ kfree(m);
+}
+
+/*
+ * Handle RCU callback
+ */
+static void pio_map_rcu_callback(struct rcu_head *list)
+{
+ struct pio_vl_map *m = container_of(list, struct pio_vl_map, list);
+
+ pio_map_free(m);
+}
+
+/*
+ * pio_map_init - called when #vls change
+ * @dd: hfi1_devdata
+ * @port: port number
+ * @num_vls: number of vls
+ * @vl_scontexts: per vl send context mapping (optional)
+ *
+ * This routine changes the mapping based on the number of vls.
+ *
+ * vl_scontexts is used to specify a non-uniform vl/send context
+ * loading. NULL implies auto computing the loading and giving each
+ * VL an uniform distribution of send contexts per VL.
+ *
+ * The auto algorithm computers the sc_per_vl and the number of extra
+ * send contexts. Any extra send contexts are added from the last VL
+ * on down
+ *
+ * rcu locking is used here to control access to the mapping fields.
+ *
+ * If either the num_vls or num_send_contexts are non-power of 2, the
+ * array sizes in the struct pio_vl_map and the struct pio_map_elem are
+ * rounded up to the next highest power of 2 and the first entry is
+ * reused in a round robin fashion.
+ *
+ * If an error occurs the map change is not done and the mapping is not
+ * chaged.
+ *
+ */
+int pio_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls, u8 *vl_scontexts)
+{
+ int i, j;
+ int extra, sc_per_vl;
+ int scontext = 1;
+ int num_kernel_send_contexts = 0;
+ u8 lvl_scontexts[OPA_MAX_VLS];
+ struct pio_vl_map *oldmap, *newmap;
+
+ if (!vl_scontexts) {
+ /* send context 0 reserved for VL15 */
+ for (i = 1; i < dd->num_send_contexts; i++)
+ if (dd->send_contexts[i].type == SC_KERNEL)
+ num_kernel_send_contexts++;
+ /* truncate divide */
+ sc_per_vl = num_kernel_send_contexts / num_vls;
+ /* extras */
+ extra = num_kernel_send_contexts % num_vls;
+ vl_scontexts = lvl_scontexts;
+ /* add extras from last vl down */
+ for (i = num_vls - 1; i >= 0; i--, extra--)
+ vl_scontexts[i] = sc_per_vl + (extra > 0 ? 1 : 0);
+ }
+ /* build new map */
+ newmap = kzalloc(sizeof(*newmap) +
+ roundup_pow_of_two(num_vls) *
+ sizeof(struct pio_map_elem *),
+ GFP_KERNEL);
+ if (!newmap)
+ goto bail;
+ newmap->actual_vls = num_vls;
+ newmap->vls = roundup_pow_of_two(num_vls);
+ newmap->mask = (1 << ilog2(newmap->vls)) - 1;
+ for (i = 0; i < newmap->vls; i++) {
+ /* save for wrap around */
+ int first_scontext = scontext;
+
+ if (i < newmap->actual_vls) {
+ int sz = roundup_pow_of_two(vl_scontexts[i]);
+
+ /* only allocate once */
+ newmap->map[i] = kzalloc(sizeof(*newmap->map[i]) +
+ sz * sizeof(struct
+ send_context *),
+ GFP_KERNEL);
+ if (!newmap->map[i])
+ goto bail;
+ newmap->map[i]->mask = (1 << ilog2(sz)) - 1;
+ /* assign send contexts */
+ for (j = 0; j < sz; j++) {
+ if (dd->kernel_send_context[scontext])
+ newmap->map[i]->ksc[j] =
+ dd->kernel_send_context[scontext];
+ if (++scontext >= first_scontext +
+ vl_scontexts[i])
+ /* wrap back to first send context */
+ scontext = first_scontext;
+ }
+ } else {
+ /* just re-use entry without allocating */
+ newmap->map[i] = newmap->map[i % num_vls];
+ }
+ scontext = first_scontext + vl_scontexts[i];
+ }
+ /* newmap in hand, save old map */
+ spin_lock_irq(&dd->pio_map_lock);
+ oldmap = rcu_dereference_protected(dd->pio_map,
+ lockdep_is_held(&dd->pio_map_lock));
+
+ /* publish newmap */
+ rcu_assign_pointer(dd->pio_map, newmap);
+
+ spin_unlock_irq(&dd->pio_map_lock);
+ /* success, free any old map after grace period */
+ if (oldmap)
+ call_rcu(&oldmap->list, pio_map_rcu_callback);
+ return 0;
+bail:
+ /* free any partial allocation */
+ pio_map_free(newmap);
+ return -ENOMEM;
+}
+
+void free_pio_map(struct hfi1_devdata *dd)
+{
+ /* Free PIO map if allocated */
+ if (rcu_access_pointer(dd->pio_map)) {
+ spin_lock_irq(&dd->pio_map_lock);
+ kfree(rcu_access_pointer(dd->pio_map));
+ RCU_INIT_POINTER(dd->pio_map, NULL);
+ spin_unlock_irq(&dd->pio_map_lock);
+ synchronize_rcu();
+ }
+ kfree(dd->kernel_send_context);
+ dd->kernel_send_context = NULL;
+}
+
int init_pervl_scs(struct hfi1_devdata *dd)
{
int i;
- u64 mask, all_vl_mask = (u64) 0x80ff; /* VLs 0-7, 15 */
+ u64 mask, all_vl_mask = (u64)0x80ff; /* VLs 0-7, 15 */
+ u64 data_vls_mask = (u64)0x00ff; /* VLs 0-7 */
u32 ctxt;
+ struct hfi1_pportdata *ppd = dd->pport;
dd->vld[15].sc = sc_alloc(dd, SC_KERNEL,
dd->rcd[0]->rcvhdrqentsize, dd->node);
goto nomem;
hfi1_init_ctxt(dd->vld[15].sc);
dd->vld[15].mtu = enum_to_mtu(OPA_MTU_2048);
+
+ dd->kernel_send_context = kmalloc_node(dd->num_send_contexts *
+ sizeof(struct send_context *),
+ GFP_KERNEL, dd->node);
+ dd->kernel_send_context[0] = dd->vld[15].sc;
+
for (i = 0; i < num_vls; i++) {
/*
* Since this function does not deal with a specific
dd->rcd[0]->rcvhdrqentsize, dd->node);
if (!dd->vld[i].sc)
goto nomem;
-
+ dd->kernel_send_context[i + 1] = dd->vld[i].sc;
hfi1_init_ctxt(dd->vld[i].sc);
-
/* non VL15 start with the max MTU */
dd->vld[i].mtu = hfi1_max_mtu;
}
+ for (i = num_vls; i < INIT_SC_PER_VL * num_vls; i++) {
+ dd->kernel_send_context[i + 1] =
+ sc_alloc(dd, SC_KERNEL, dd->rcd[0]->rcvhdrqentsize, dd->node);
+ if (!dd->kernel_send_context[i + 1])
+ goto nomem;
+ hfi1_init_ctxt(dd->kernel_send_context[i + 1]);
+ }
+
sc_enable(dd->vld[15].sc);
ctxt = dd->vld[15].sc->hw_context;
mask = all_vl_mask & ~(1LL << 15);
dd_dev_info(dd,
"Using send context %u(%u) for VL15\n",
dd->vld[15].sc->sw_index, ctxt);
+
for (i = 0; i < num_vls; i++) {
sc_enable(dd->vld[i].sc);
ctxt = dd->vld[i].sc->hw_context;
- mask = all_vl_mask & ~(1LL << i);
+ mask = all_vl_mask & ~(data_vls_mask);
write_kctxt_csr(dd, ctxt, SC(CHECK_VL), mask);
}
+ for (i = num_vls; i < INIT_SC_PER_VL * num_vls; i++) {
+ sc_enable(dd->kernel_send_context[i + 1]);
+ ctxt = dd->kernel_send_context[i + 1]->hw_context;
+ mask = all_vl_mask & ~(data_vls_mask);
+ write_kctxt_csr(dd, ctxt, SC(CHECK_VL), mask);
+ }
+
+ if (pio_map_init(dd, ppd->port - 1, num_vls, NULL))
+ goto nomem;
return 0;
nomem:
sc_free(dd->vld[15].sc);
for (i = 0; i < num_vls; i++)
sc_free(dd->vld[i].sc);
+ for (i = num_vls; i < INIT_SC_PER_VL * num_vls; i++)
+ sc_free(dd->kernel_send_context[i + 1]);
return -ENOMEM;
}
short int count;
};
+/*
+ * The diagram below details the relationship of the mapping structures
+ *
+ * Since the mapping now allows for non-uniform send contexts per vl, the
+ * number of send contexts for a vl is either the vl_scontexts[vl] or
+ * a computation based on num_kernel_send_contexts/num_vls:
+ *
+ * For example:
+ * nactual = vl_scontexts ? vl_scontexts[vl] : num_kernel_send_contexts/num_vls
+ *
+ * n = roundup to next highest power of 2 using nactual
+ *
+ * In the case where there are num_kernel_send_contexts/num_vls doesn't divide
+ * evenly, the extras are added from the last vl downward.
+ *
+ * For the case where n > nactual, the send contexts are assigned
+ * in a round robin fashion wrapping back to the first send context
+ * for a particular vl.
+ *
+ * dd->pio_map
+ * | pio_map_elem[0]
+ * | +--------------------+
+ * v | mask |
+ * pio_vl_map |--------------------|
+ * +--------------------------+ | ksc[0] -> sc 1 |
+ * | list (RCU) | |--------------------|
+ * |--------------------------| ->| ksc[1] -> sc 2 |
+ * | mask | --/ |--------------------|
+ * |--------------------------| -/ | * |
+ * | actual_vls (max 8) | -/ |--------------------|
+ * |--------------------------| --/ | ksc[n] -> sc n |
+ * | vls (max 8) | -/ +--------------------+
+ * |--------------------------| --/
+ * | map[0] |-/
+ * |--------------------------| +--------------------+
+ * | map[1] |--- | mask |
+ * |--------------------------| \---- |--------------------|
+ * | * | \-- | ksc[0] -> sc 1+n |
+ * | * | \---- |--------------------|
+ * | * | \->| ksc[1] -> sc 2+n |
+ * |--------------------------| |--------------------|
+ * | map[vls - 1] |- | * |
+ * +--------------------------+ \- |--------------------|
+ * \- | ksc[m] -> sc m+n |
+ * \ +--------------------+
+ * \-
+ * \
+ * \- +--------------------+
+ * \- | mask |
+ * \ |--------------------|
+ * \- | ksc[0] -> sc 1+m+n |
+ * \- |--------------------|
+ * >| ksc[1] -> sc 2+m+n |
+ * |--------------------|
+ * | * |
+ * |--------------------|
+ * | ksc[o] -> sc o+m+n |
+ * +--------------------+
+ *
+ */
+
+/* Initial number of send contexts per VL */
+#define INIT_SC_PER_VL 2
+
+/*
+ * struct pio_map_elem - mapping for a vl
+ * @mask - selector mask
+ * @ksc - array of kernel send contexts for this vl
+ *
+ * The mask is used to "mod" the selector to
+ * produce index into the trailing array of
+ * kscs
+ */
+struct pio_map_elem {
+ u32 mask;
+ struct send_context *ksc[0];
+};
+
+/*
+ * struct pio_vl_map - mapping for a vl
+ * @list - rcu head for free callback
+ * @mask - vl mask to "mod" the vl to produce an index to map array
+ * @actual_vls - number of vls
+ * @vls - numbers of vls rounded to next power of 2
+ * @map - array of pio_map_elem entries
+ *
+ * This is the parent mapping structure. The trailing members of the
+ * struct point to pio_map_elem entries, which in turn point to an
+ * array of kscs for that vl.
+ */
+struct pio_vl_map {
+ struct rcu_head list;
+ u32 mask;
+ u8 actual_vls;
+ u8 vls;
+ struct pio_map_elem *map[0];
+};
+
+int pio_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls,
+ u8 *vl_scontexts);
+void free_pio_map(struct hfi1_devdata *dd);
+struct send_context *pio_select_send_context_vl(struct hfi1_devdata *dd,
+ u32 selector, u8 vl);
+struct send_context *pio_select_send_context_sc(struct hfi1_devdata *dd,
+ u32 selector, u8 sc5);
+
/* send context functions */
int init_credit_return(struct hfi1_devdata *dd);
void free_credit_return(struct hfi1_devdata *dd);