IB/hfi1: Immediately apply congestion setting MAD

The handling of the congestion setting MAD packet only
saved off the values, waiting for a congestion control
table packet before going active.  Instead, immediately
apply the values.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/staging/rdma/hfi1/mad.c b/drivers/staging/rdma/hfi1/mad.c
index ed58cf2..17882dc 100644 (file)
--- a/drivers/staging/rdma/hfi1/mad.c
+++ b/drivers/staging/rdma/hfi1/mad.c
@@ -3363,6 +3363,50 @@ static int __subn_get_opa_cong_setting(struct opa_smp *smp, u32 am,
        return reply((struct ib_mad_hdr *)smp);
 }
 
+/*
+ * Apply congestion control information stored in the ppd to the
+ * active structure.
+ */
+static void apply_cc_state(struct hfi1_pportdata *ppd)
+{
+       struct cc_state *old_cc_state, *new_cc_state;
+
+       new_cc_state = kzalloc(sizeof(*new_cc_state), GFP_KERNEL);
+       if (!new_cc_state)
+               return;
+
+       /*
+        * Hold the lock for updating *and* to prevent ppd information
+        * from changing during the update.
+        */
+       spin_lock(&ppd->cc_state_lock);
+
+       old_cc_state = get_cc_state(ppd);
+       if (!old_cc_state) {
+               /* never active, or shutting down */
+               spin_unlock(&ppd->cc_state_lock);
+               kfree(new_cc_state);
+               return;
+       }
+
+       *new_cc_state = *old_cc_state;
+
+       new_cc_state->cct.ccti_limit = ppd->total_cct_entry - 1;
+       memcpy(new_cc_state->cct.entries, ppd->ccti_entries,
+              ppd->total_cct_entry * sizeof(struct ib_cc_table_entry));
+
+       new_cc_state->cong_setting.port_control = IB_CC_CCS_PC_SL_BASED;
+       new_cc_state->cong_setting.control_map = ppd->cc_sl_control_map;
+       memcpy(new_cc_state->cong_setting.entries, ppd->congestion_entries,
+              OPA_MAX_SLS * sizeof(struct opa_congestion_setting_entry));
+
+       rcu_assign_pointer(ppd->cc_state, new_cc_state);
+
+       spin_unlock(&ppd->cc_state_lock);
+
+       call_rcu(&old_cc_state->rcu, cc_state_reclaim);
+}
+
 static int __subn_set_opa_cong_setting(struct opa_smp *smp, u32 am, u8 *data,
                                       struct ib_device *ibdev, u8 port,
                                       u32 *resp_len)
@@ -3374,6 +3418,11 @@ static int __subn_set_opa_cong_setting(struct opa_smp *smp, u32 am, u8 *data,
        struct opa_congestion_setting_entry_shadow *entries;
        int i;
 
+       /*
+        * Save details from packet into the ppd.  Hold the cc_state_lock so
+        * our information is consistent with anyone trying to apply the state.
+        */
+       spin_lock(&ppd->cc_state_lock);
        ppd->cc_sl_control_map = be32_to_cpu(p->control_map);
 
        entries = ppd->congestion_entries;
@@ -3384,6 +3433,10 @@ static int __subn_set_opa_cong_setting(struct opa_smp *smp, u32 am, u8 *data,
                        p->entries[i].trigger_threshold;
                entries[i].ccti_min = p->entries[i].ccti_min;
        }
+       spin_unlock(&ppd->cc_state_lock);
+
+       /* now apply the information */
+       apply_cc_state(ppd);
 
        return __subn_get_opa_cong_setting(smp, am, data, ibdev, port,
                                           resp_len);
@@ -3526,7 +3579,6 @@ static int __subn_set_opa_cc_table(struct opa_smp *smp, u32 am, u8 *data,
        int i, j;
        u32 sentry, eentry;
        u16 ccti_limit;
-       struct cc_state *old_cc_state, *new_cc_state;
 
        /* sanity check n_blocks, start_block */
        if (n_blocks == 0 ||
@@ -3546,45 +3598,20 @@ static int __subn_set_opa_cc_table(struct opa_smp *smp, u32 am, u8 *data,
                return reply((struct ib_mad_hdr *)smp);
        }
 
-       new_cc_state = kzalloc(sizeof(*new_cc_state), GFP_KERNEL);
-       if (!new_cc_state)
-               goto getit;
-
+       /*
+        * Save details from packet into the ppd.  Hold the cc_state_lock so
+        * our information is consistent with anyone trying to apply the state.
+        */
        spin_lock(&ppd->cc_state_lock);
-
-       old_cc_state = get_cc_state(ppd);
-
-       if (!old_cc_state) {
-               spin_unlock(&ppd->cc_state_lock);
-               kfree(new_cc_state);
-               return reply((struct ib_mad_hdr *)smp);
-       }
-
-       *new_cc_state = *old_cc_state;
-
-       new_cc_state->cct.ccti_limit = ccti_limit;
-
-       entries = ppd->ccti_entries;
        ppd->total_cct_entry = ccti_limit + 1;
-
+       entries = ppd->ccti_entries;
        for (j = 0, i = sentry; i < eentry; j++, i++)
                entries[i].entry = be16_to_cpu(p->ccti_entries[j].entry);
-
-       memcpy(new_cc_state->cct.entries, entries,
-              eentry * sizeof(struct ib_cc_table_entry));
-
-       new_cc_state->cong_setting.port_control = IB_CC_CCS_PC_SL_BASED;
-       new_cc_state->cong_setting.control_map = ppd->cc_sl_control_map;
-       memcpy(new_cc_state->cong_setting.entries, ppd->congestion_entries,
-              OPA_MAX_SLS * sizeof(struct opa_congestion_setting_entry));
-
-       rcu_assign_pointer(ppd->cc_state, new_cc_state);
-
        spin_unlock(&ppd->cc_state_lock);
 
-       call_rcu(&old_cc_state->rcu, cc_state_reclaim);
+       /* now apply the information */
+       apply_cc_state(ppd);
 
-getit:
        return __subn_get_opa_cc_table(smp, am, data, ibdev, port, resp_len);
 }