IB/hfi1: Fix credit return threshold adjustment

The credit return threshold adjustment on mtu change algorithm does not
take into account all the kernel send contexts that are assigned per VL.
Use the pio send context map to adjust the credit return thresholds for
all the allocated and assigned kernel send contexts based on the MTU
adjustment per VL.

The pio send context map can be changed dynamically based on the actual
number of operational vls which is set by the fabric manager. When this
happens update the credit return threshold values for all the remapped
kernel send contexts.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Jianxin Xiong <jianxin.xiong@intel.com>
Signed-off-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 81619fbb5842dc8fdd4b0b344f5333b711d7e77e..c533d44223997f8def9cc7e9bdf9a6868e809355 100644 (file)
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -9777,7 +9777,7 @@ static void set_send_length(struct hfi1_pportdata *ppd)
        u64 len1 = 0, len2 = (((dd->vld[15].mtu + max_hb) >> 2)
                              & SEND_LEN_CHECK1_LEN_VL15_MASK) <<
                SEND_LEN_CHECK1_LEN_VL15_SHIFT;
-       int i;
+       int i, j;
        u32 thres;
 
        for (i = 0; i < ppd->vls_supported; i++) {
@@ -9801,7 +9801,10 @@ static void set_send_length(struct hfi1_pportdata *ppd)
                            sc_mtu_to_threshold(dd->vld[i].sc,
                                                dd->vld[i].mtu,
                                                dd->rcd[0]->rcvhdrqentsize));
-               sc_set_cr_threshold(dd->vld[i].sc, thres);
+               for (j = 0; j < INIT_SC_PER_VL; j++)
+                       sc_set_cr_threshold(
+                                       pio_select_send_context_vl(dd, j, i),
+                                           thres);
        }
        thres = min(sc_percent_to_threshold(dd->vld[15].sc, 50),
                    sc_mtu_to_threshold(dd->vld[15].sc,

diff --git a/drivers/infiniband/hw/hfi1/pio.c b/drivers/infiniband/hw/hfi1/pio.c
index d5edb1afbb8f8b8ed98135bfc9b961e00d535b4e..e0e1ff2a0c72a37928a13df636da93efc0d6d15a 100644 (file)
--- a/drivers/infiniband/hw/hfi1/pio.c
+++ b/drivers/infiniband/hw/hfi1/pio.c
@@ -1797,6 +1797,21 @@ static void pio_map_rcu_callback(struct rcu_head *list)
        pio_map_free(m);
 }
 
+/*
+ * Set credit return threshold for the kernel send context
+ */
+static void set_threshold(struct hfi1_devdata *dd, int scontext, int i)
+{
+       u32 thres;
+
+       thres = min(sc_percent_to_threshold(dd->kernel_send_context[scontext],
+                                           50),
+                   sc_mtu_to_threshold(dd->kernel_send_context[scontext],
+                                       dd->vld[i].mtu,
+                                       dd->rcd[0]->rcvhdrqentsize));
+       sc_set_cr_threshold(dd->kernel_send_context[scontext], thres);
+}
+
 /*
  * pio_map_init - called when #vls change
  * @dd: hfi1_devdata
@@ -1872,11 +1887,16 @@ int pio_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls, u8 *vl_scontexts)
                        if (!newmap->map[i])
                                goto bail;
                        newmap->map[i]->mask = (1 << ilog2(sz)) - 1;
-                       /* assign send contexts */
+                       /*
+                        * assign send contexts and
+                        * adjust credit return threshold
+                        */
                        for (j = 0; j < sz; j++) {
-                               if (dd->kernel_send_context[scontext])
+                               if (dd->kernel_send_context[scontext]) {
                                        newmap->map[i]->ksc[j] =
                                        dd->kernel_send_context[scontext];
+                                       set_threshold(dd, scontext, i);
+                               }
                                if (++scontext >= first_scontext +
                                                  vl_scontexts[i])
                                        /* wrap back to first send context */