staging/rdma/hfi1: Fix for 32-bit counter overflow in driver and hfi1stats

When 32-bit hardware counters overflow, hfi1stats misinterprets
the counters as being 64 bits causing the deltas for the
counters to be a huge number. This patch makes hfi1stats
aware that a counter is 32 bits by making the driver write
<counter name>,32 to debugfs.

Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/staging/rdma/hfi1/chip.c b/drivers/staging/rdma/hfi1/chip.c
index d45e271..a90e6e6 100644 (file)
--- a/drivers/staging/rdma/hfi1/chip.c
+++ b/drivers/staging/rdma/hfi1/chip.c
@@ -11766,6 +11766,8 @@ static int init_cntrs(struct hfi1_devdata *dd)
        char *p;
        char name[C_MAX_NAME];
        struct hfi1_pportdata *ppd;
+       const char *bit_type_32 = ",32";
+       const int bit_type_32_sz = strlen(bit_type_32);
 
        /* set up the stats timer; the add_timer is done at the end */
        setup_timer(&dd->synth_stats_timer, update_synth_timer,
@@ -11795,6 +11797,9 @@ static int init_cntrs(struct hfi1_devdata *dd)
                                        dev_cntrs[i].name,
                                        vl_from_idx(j));
                                sz += strlen(name);
+                               /* Add ",32" for 32-bit counters */
+                               if (dev_cntrs[i].flags & CNTR_32BIT)
+                                       sz += bit_type_32_sz;
                                sz++;
                                hfi1_dbg_early("\t\t%s\n", name);
                                dd->ndevcntrs++;
@@ -11809,13 +11814,19 @@ static int init_cntrs(struct hfi1_devdata *dd)
                                snprintf(name, C_MAX_NAME, "%s%d",
                                         dev_cntrs[i].name, j);
                                sz += strlen(name);
+                               /* Add ",32" for 32-bit counters */
+                               if (dev_cntrs[i].flags & CNTR_32BIT)
+                                       sz += bit_type_32_sz;
                                sz++;
                                hfi1_dbg_early("\t\t%s\n", name);
                                dd->ndevcntrs++;
                        }
                } else {
-                       /* +1 for newline  */
+                       /* +1 for newline. */
                        sz += strlen(dev_cntrs[i].name) + 1;
+                       /* Add ",32" for 32-bit counters */
+                       if (dev_cntrs[i].flags & CNTR_32BIT)
+                               sz += bit_type_32_sz;
                        dev_cntrs[i].offset = dd->ndevcntrs;
                        dd->ndevcntrs++;
                        hfi1_dbg_early("\tAdding %s\n", dev_cntrs[i].name);
@@ -11842,33 +11853,50 @@ static int init_cntrs(struct hfi1_devdata *dd)
        for (p = dd->cntrnames, i = 0; i < DEV_CNTR_LAST; i++) {
                if (dev_cntrs[i].flags & CNTR_DISABLED) {
                        /* Nothing */
-               } else {
-                       if (dev_cntrs[i].flags & CNTR_VL) {
-                               for (j = 0; j < C_VL_COUNT; j++) {
-                                       memset(name, '\0', C_MAX_NAME);
-                                       snprintf(name, C_MAX_NAME, "%s%d",
-                                               dev_cntrs[i].name,
-                                               vl_from_idx(j));
-                                       memcpy(p, name, strlen(name));
-                                       p += strlen(name);
-                                       *p++ = '\n';
+               } else if (dev_cntrs[i].flags & CNTR_VL) {
+                       for (j = 0; j < C_VL_COUNT; j++) {
+                               memset(name, '\0', C_MAX_NAME);
+                               snprintf(name, C_MAX_NAME, "%s%d",
+                                        dev_cntrs[i].name,
+                                        vl_from_idx(j));
+                               memcpy(p, name, strlen(name));
+                               p += strlen(name);
+
+                               /* Counter is 32 bits */
+                               if (dev_cntrs[i].flags & CNTR_32BIT) {
+                                       memcpy(p, bit_type_32, bit_type_32_sz);
+                                       p += bit_type_32_sz;
                                }
-                       } else if (dev_cntrs[i].flags & CNTR_SDMA) {
-                               for (j = 0; j < TXE_NUM_SDMA_ENGINES;
-                                    j++) {
-                                       memset(name, '\0', C_MAX_NAME);
-                                       snprintf(name, C_MAX_NAME, "%s%d",
-                                                dev_cntrs[i].name, j);
-                                       memcpy(p, name, strlen(name));
-                                       p += strlen(name);
-                                       *p++ = '\n';
+
+                               *p++ = '\n';
+                       }
+               } else if (dev_cntrs[i].flags & CNTR_SDMA) {
+                       for (j = 0; j < dd->chip_sdma_engines; j++) {
+                               memset(name, '\0', C_MAX_NAME);
+                               snprintf(name, C_MAX_NAME, "%s%d",
+                                        dev_cntrs[i].name, j);
+                               memcpy(p, name, strlen(name));
+                               p += strlen(name);
+
+                               /* Counter is 32 bits */
+                               if (dev_cntrs[i].flags & CNTR_32BIT) {
+                                       memcpy(p, bit_type_32, bit_type_32_sz);
+                                       p += bit_type_32_sz;
                                }
-                       } else {
-                               memcpy(p, dev_cntrs[i].name,
-                                      strlen(dev_cntrs[i].name));
-                               p += strlen(dev_cntrs[i].name);
+
                                *p++ = '\n';
                        }
+               } else {
+                       memcpy(p, dev_cntrs[i].name, strlen(dev_cntrs[i].name));
+                       p += strlen(dev_cntrs[i].name);
+
+                       /* Counter is 32 bits */
+                       if (dev_cntrs[i].flags & CNTR_32BIT) {
+                               memcpy(p, bit_type_32, bit_type_32_sz);
+                               p += bit_type_32_sz;
+                       }
+
+                       *p++ = '\n';
                }
        }
 
@@ -11906,13 +11934,19 @@ static int init_cntrs(struct hfi1_devdata *dd)
                                        port_cntrs[i].name,
                                        vl_from_idx(j));
                                sz += strlen(name);
+                               /* Add ",32" for 32-bit counters */
+                               if (port_cntrs[i].flags & CNTR_32BIT)
+                                       sz += bit_type_32_sz;
                                sz++;
                                hfi1_dbg_early("\t\t%s\n", name);
                                dd->nportcntrs++;
                        }
                } else {
-                       /* +1 for newline  */
+                       /* +1 for newline */
                        sz += strlen(port_cntrs[i].name) + 1;
+                       /* Add ",32" for 32-bit counters */
+                       if (port_cntrs[i].flags & CNTR_32BIT)
+                               sz += bit_type_32_sz;
                        port_cntrs[i].offset = dd->nportcntrs;
                        dd->nportcntrs++;
                        hfi1_dbg_early("\tAdding %s\n", port_cntrs[i].name);
@@ -11938,12 +11972,26 @@ static int init_cntrs(struct hfi1_devdata *dd)
                                        vl_from_idx(j));
                                memcpy(p, name, strlen(name));
                                p += strlen(name);
+
+                               /* Counter is 32 bits */
+                               if (port_cntrs[i].flags & CNTR_32BIT) {
+                                       memcpy(p, bit_type_32, bit_type_32_sz);
+                                       p += bit_type_32_sz;
+                               }
+
                                *p++ = '\n';
                        }
                } else {
                        memcpy(p, port_cntrs[i].name,
                               strlen(port_cntrs[i].name));
                        p += strlen(port_cntrs[i].name);
+
+                       /* Counter is 32 bits */
+                       if (port_cntrs[i].flags & CNTR_32BIT) {
+                               memcpy(p, bit_type_32, bit_type_32_sz);
+                               p += bit_type_32_sz;
+                       }
+
                        *p++ = '\n';
                }
        }