use refcnt API for multicast addresses, add tracepoint:refcnt:ethmulti probe

Replace hand-rolled reference counting with refcnt_init(9) and hook it up
with a new dt(4) probe.

OK mvs
Feedback OK bluhm

diff --git a/sys/dev/dt/dt_prov_static.c b/sys/dev/dt/dt_prov_static.c
index e446844..dc23981 100644 (file)
--- a/sys/dev/dt/dt_prov_static.c
+++ b/sys/dev/dt/dt_prov_static.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: dt_prov_static.c,v 1.19 2023/06/28 11:49:49 kn Exp $ */
+/*     $OpenBSD: dt_prov_static.c,v 1.20 2023/07/06 19:46:53 kn Exp $ */
 
 /*
  * Copyright (c) 2019 Martin Pieuchot <mpi@openbsd.org>
@@ -92,6 +92,7 @@ DT_STATIC_PROBE2(smr, thread, "uint64_t", "uint64_t");
  * reference counting, keep in sync with sys/refcnt.h
  */
 DT_STATIC_PROBE0(refcnt, none);
+DT_STATIC_PROBE3(refcnt, ethmulti, "void *", "int", "int");
 DT_STATIC_PROBE3(refcnt, ifaddr, "void *", "int", "int");
 DT_STATIC_PROBE3(refcnt, ifmaddr, "void *", "int", "int");
 DT_STATIC_PROBE3(refcnt, inpcb, "void *", "int", "int");
@@ -140,6 +141,7 @@ struct dt_probe *const dtps_static[] = {
        &_DT_STATIC_P(smr, thread),
        /* refcnt */
        &_DT_STATIC_P(refcnt, none),
+       &_DT_STATIC_P(refcnt, ethmulti),
        &_DT_STATIC_P(refcnt, ifaddr),
        &_DT_STATIC_P(refcnt, ifmaddr),
        &_DT_STATIC_P(refcnt, inpcb),

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index 4656fd8..20f7a9a 100644 (file)
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_ethersubr.c,v 1.289 2023/07/03 15:52:51 kn Exp $   */
+/*     $OpenBSD: if_ethersubr.c,v 1.290 2023/07/06 19:46:53 kn Exp $   */
 /*     $NetBSD: if_ethersubr.c,v 1.19 1996/05/07 02:40:30 thorpej Exp $        */
 
 /*
@@ -931,7 +931,7 @@ ether_addmulti(struct ifreq *ifr, struct arpcom *ac)
                /*
                 * Found it; just increment the reference count.
                 */
-               ++enm->enm_refcount;
+               refcnt_take(&enm->enm_refcnt);
                splx(s);
                return (0);
        }
@@ -946,7 +946,7 @@ ether_addmulti(struct ifreq *ifr, struct arpcom *ac)
        }
        memcpy(enm->enm_addrlo, addrlo, ETHER_ADDR_LEN);
        memcpy(enm->enm_addrhi, addrhi, ETHER_ADDR_LEN);
-       enm->enm_refcount = 1;
+       refcnt_init_trace(&enm->enm_refcnt, DT_REFCNT_IDX_ETHMULTI);
        LIST_INSERT_HEAD(&ac->ac_multiaddrs, enm, enm_list);
        ac->ac_multicnt++;
        if (memcmp(addrlo, addrhi, ETHER_ADDR_LEN) != 0)
@@ -984,7 +984,7 @@ ether_delmulti(struct ifreq *ifr, struct arpcom *ac)
                splx(s);
                return (ENXIO);
        }
-       if (--enm->enm_refcount != 0) {
+       if (refcnt_rele(&enm->enm_refcnt) == 0) {
                /*
                 * Still some claims to this record.
                 */

diff --git a/sys/netinet/if_ether.h b/sys/netinet/if_ether.h
index f05dbf4..9ff5bae 100644 (file)
--- a/sys/netinet/if_ether.h
+++ b/sys/netinet/if_ether.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_ether.h,v 1.88 2023/02/07 16:14:55 bluhm Exp $     */
+/*     $OpenBSD: if_ether.h,v 1.89 2023/07/06 19:46:53 kn Exp $        */
 /*     $NetBSD: if_ether.h,v 1.22 1996/05/11 13:00:00 mycroft Exp $    */
 
 /*
@@ -181,6 +181,9 @@ struct sockaddr_inarp {
 #define        RTF_PERMANENT_ARP RTF_PROTO3    /* only manual overwrite of entry */
 
 #ifdef _KERNEL
+
+#include <sys/refcnt.h>
+
 /*
  * Macro to map an IP multicast address to an Ethernet multicast address.
  * The high-order 25 bits of the Ethernet address are statically assigned,
@@ -318,7 +321,7 @@ void ether_extract_headers(struct mbuf *, struct ether_extracted *);
 struct ether_multi {
        u_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
        u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
-       u_int    enm_refcount;          /* no. claims to this addr/range */
+       struct refcnt enm_refcnt;               /* no. claims to this addr/range */
        LIST_ENTRY(ether_multi) enm_list;
 };
 

diff --git a/sys/sys/refcnt.h b/sys/sys/refcnt.h
index 47a40f6..c0f0482 100644 (file)
--- a/sys/sys/refcnt.h
+++ b/sys/sys/refcnt.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: refcnt.h,v 1.10 2023/06/28 11:49:49 kn Exp $ */
+/*     $OpenBSD: refcnt.h,v 1.11 2023/07/06 19:46:53 kn Exp $ */
 
 /*
  * Copyright (c) 2015 David Gwynne <dlg@openbsd.org>
@@ -44,11 +44,12 @@ int refcnt_shared(struct refcnt *);
 unsigned int   refcnt_read(struct refcnt *);
 
 /* sorted alphabetically, keep in sync with dev/dt/dt_prov_static.c */
-#define DT_REFCNT_IDX_IFADDR   1
-#define DT_REFCNT_IDX_IFMADDR  2
-#define DT_REFCNT_IDX_INPCB    3
-#define DT_REFCNT_IDX_RTENTRY  4
-#define DT_REFCNT_IDX_TDB      5
+#define DT_REFCNT_IDX_ETHMULTI 1
+#define DT_REFCNT_IDX_IFADDR   2
+#define DT_REFCNT_IDX_IFMADDR  3
+#define DT_REFCNT_IDX_INPCB    4
+#define DT_REFCNT_IDX_RTENTRY  5
+#define DT_REFCNT_IDX_TDB      6
 
 #endif /* _KERNEL */