give softnet threads their own names

[David Gwynne]

so in top you see softnet0, softnet1, etc.

the real change is putting a struct softnet in place to wrap the name
and taskq up with.

ok?

Index: if.c
===================================================================
RCS file: /cvs/src/sys/net/if.c,v
retrieving revision 1.695
diff -u -p -r1.695 if.c
--- if.c        7 May 2023 16:23:23 -0000       1.695
+++ if.c        12 May 2023 00:19:38 -0000
@@ -243,8 +243,13 @@ int        ifq_congestion;
 
 int             netisr;
 
+struct softnet {
+       char             sn_name[16];
+       struct taskq    *sn_taskq;
+};
+
 #define        NET_TASKQ       4
-struct taskq   *nettqmp[NET_TASKQ];
+struct softnet softnets[NET_TASKQ];
 
 struct task if_input_task_locked = TASK_INITIALIZER(if_netisr, NULL);
 
@@ -269,8 +274,11 @@ ifinit(void)
        if_idxmap_init(8); /* 8 is a nice power of 2 for malloc */
 
        for (i = 0; i < NET_TASKQ; i++) {
-               nettqmp[i] = taskq_create("softnet", 1, IPL_NET, TASKQ_MPSAFE);
-               if (nettqmp[i] == NULL)
+               struct softnet *sn = &softnets[i];
+               snprintf(sn->sn_name, sizeof(sn->sn_name), "softnet%u", i);
+               sn->sn_taskq = taskq_create(sn->sn_name, 1, IPL_NET,
+                   TASKQ_MPSAFE);
+               if (sn->sn_taskq == NULL)
                        panic("unable to create network taskq %d", i);
        }
 }
@@ -3463,13 +3471,13 @@ unhandled_af(int af)
 struct taskq *
 net_tq(unsigned int ifindex)
 {
-       struct taskq *t = NULL;
+       struct softnet *sn;
        static int nettaskqs;
 
        if (nettaskqs == 0)
                nettaskqs = min(NET_TASKQ, ncpus);
 
-       t = nettqmp[ifindex % nettaskqs];
+       sn = &softnets[ifindex % nettaskqs];
 
-       return (t);
+       return (sn->sn_taskq);
 }