I still think it is worth to have refcount debugging in generic
kernel dt(4). Having tools is easier than first adding printf to
hunt a bug. I see no downside.
ok?
bluhm
Index: dev/dt/dt_prov_static.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/dev/dt/dt_prov_static.c,v
retrieving revision 1.13
diff -u -p -r1.13 dt_prov_static.c
--- dev/dt/dt_prov_static.c 17 Mar 2022 14:53:59 -0000 1.13
+++ dev/dt/dt_prov_static.c 21 Apr 2022 21:06:03 -0000
@@ -87,6 +87,12 @@ DT_STATIC_PROBE1(smr, barrier_exit, "int
DT_STATIC_PROBE0(smr, wakeup);
DT_STATIC_PROBE2(smr, thread, "uint64_t", "uint64_t");
+/*
+ * reference counting
+ */
+DT_STATIC_PROBE0(refcnt, none);
+DT_STATIC_PROBE3(refcnt, inpcb, "void *", "int", "int");
+DT_STATIC_PROBE3(refcnt, tdb, "void *", "int", "int");
/*
* List of all static probes
@@ -127,15 +133,24 @@ struct dt_probe *const dtps_static[] = {
&_DT_STATIC_P(smr, barrier_exit),
&_DT_STATIC_P(smr, wakeup),
&_DT_STATIC_P(smr, thread),
+ /* refcnt */
+ &_DT_STATIC_P(refcnt, none),
+ &_DT_STATIC_P(refcnt, inpcb),
+ &_DT_STATIC_P(refcnt, tdb),
};
+struct dt_probe *const *dtps_index_refcnt;
+
int
dt_prov_static_init(void)
{
int i;
- for (i = 0; i < nitems(dtps_static); i++)
+ for (i = 0; i < nitems(dtps_static); i++) {
+ if (dtps_static[i] == &_DT_STATIC_P(refcnt, none))
+ dtps_index_refcnt = &dtps_static[i];
dt_dev_register_probe(dtps_static[i]);
+ }
return i;
}
Index: dev/dt/dtvar.h
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/dev/dt/dtvar.h,v
retrieving revision 1.13
diff -u -p -r1.13 dtvar.h
--- dev/dt/dtvar.h 27 Feb 2022 10:14:01 -0000 1.13
+++ dev/dt/dtvar.h 21 Apr 2022 21:06:03 -0000
@@ -313,11 +313,30 @@ extern volatile uint32_t dt_tracing; /*
#define DT_STATIC_ENTER(func, name, args...) do {
\
extern struct dt_probe _DT_STATIC_P(func, name); \
struct dt_probe *dtp = &_DT_STATIC_P(func, name); \
- struct dt_provider *dtpv = dtp->dtp_prov; \
\
if (__predict_false(dt_tracing) && \
__predict_false(dtp->dtp_recording)) { \
+ struct dt_provider *dtpv = dtp->dtp_prov; \
+ \
dtpv->dtpv_enter(dtpv, dtp, args); \
+ } \
+} while (0)
+
+#define _DT_INDEX_P(func) (dtps_index_##func)
+
+#define DT_INDEX_ENTER(func, index, args...) do { \
+ extern struct dt_probe **_DT_INDEX_P(func); \
+ \
+ if (__predict_false(dt_tracing) && \
+ __predict_false(index > 0) && \
+ __predict_true(_DT_INDEX_P(func) != NULL)) { \
+ struct dt_probe *dtp = _DT_INDEX_P(func)[index]; \
+ \
+ if(__predict_false(dtp->dtp_recording)) { \
+ struct dt_provider *dtpv = dtp->dtp_prov; \
+ \
+ dtpv->dtpv_enter(dtpv, dtp, args); \
+ } \
} \
} while (0)
Index: kern/kern_synch.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/kern/kern_synch.c,v
retrieving revision 1.185
diff -u -p -r1.185 kern_synch.c
--- kern/kern_synch.c 18 Mar 2022 15:32:06 -0000 1.185
+++ kern/kern_synch.c 21 Apr 2022 21:06:03 -0000
@@ -804,7 +804,15 @@ sys___thrwakeup(struct proc *p, void *v,
void
refcnt_init(struct refcnt *r)
{
+ refcnt_init_trace(r, 0);
+}
+
+void
+refcnt_init_trace(struct refcnt *r, int idx)
+{
+ r->r_traceidx = idx;
atomic_store_int(&r->r_refs, 1);
+ TRACEINDEX(refcnt, r->r_traceidx, r, 0, +1);
}
void
@@ -814,6 +822,7 @@ refcnt_take(struct refcnt *r)
refs = atomic_inc_int_nv(&r->r_refs);
KASSERT(refs != 0);
+ TRACEINDEX(refcnt, r->r_traceidx, r, refs - 1, +1);
(void)refs;
}
@@ -824,6 +833,7 @@ refcnt_rele(struct refcnt *r)
refs = atomic_dec_int_nv(&r->r_refs);
KASSERT(refs != ~0);
+ TRACEINDEX(refcnt, r->r_traceidx, r, refs + 1, -1);
return (refs == 0);
}
@@ -842,11 +852,13 @@ refcnt_finalize(struct refcnt *r, const
refs = atomic_dec_int_nv(&r->r_refs);
KASSERT(refs != ~0);
+ TRACEINDEX(refcnt, r->r_traceidx, r, refs + 1, -1);
while (refs) {
sleep_setup(&sls, r, PWAIT, wmesg, 0);
refs = atomic_load_int(&r->r_refs);
sleep_finish(&sls, refs);
}
+ TRACEINDEX(refcnt, r->r_traceidx, r, refs, 0);
}
int
@@ -855,6 +867,7 @@ refcnt_shared(struct refcnt *r)
u_int refs;
refs = atomic_load_int(&r->r_refs);
+ TRACEINDEX(refcnt, r->r_traceidx, r, refs, 0);
return (refs > 1);
}
@@ -864,6 +877,7 @@ refcnt_read(struct refcnt *r)
u_int refs;
refs = atomic_load_int(&r->r_refs);
+ TRACEINDEX(refcnt, r->r_traceidx, r, refs, 0);
return (refs);
}
Index: netinet/in_pcb.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/in_pcb.c,v
retrieving revision 1.265
diff -u -p -r1.265 in_pcb.c
--- netinet/in_pcb.c 14 Apr 2022 14:10:22 -0000 1.265
+++ netinet/in_pcb.c 21 Apr 2022 21:06:03 -0000
@@ -235,7 +235,7 @@ in_pcballoc(struct socket *so, struct in
return (ENOBUFS);
inp->inp_table = table;
inp->inp_socket = so;
- refcnt_init(&inp->inp_refcnt);
+ refcnt_init_trace(&inp->inp_refcnt, DT_REFCNT_IDX_INPCB);
inp->inp_seclevel[SL_AUTH] = IPSEC_AUTH_LEVEL_DEFAULT;
inp->inp_seclevel[SL_ESP_TRANS] = IPSEC_ESP_TRANS_LEVEL_DEFAULT;
inp->inp_seclevel[SL_ESP_NETWORK] = IPSEC_ESP_NETWORK_LEVEL_DEFAULT;
Index: netinet/ip_ipsp.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/ip_ipsp.c,v
retrieving revision 1.269
diff -u -p -r1.269 ip_ipsp.c
--- netinet/ip_ipsp.c 10 Mar 2022 15:21:08 -0000 1.269
+++ netinet/ip_ipsp.c 21 Apr 2022 21:06:03 -0000
@@ -1048,7 +1048,7 @@ tdb_alloc(u_int rdomain)
tdbp = pool_get(&tdb_pool, PR_WAITOK | PR_ZERO);
- refcnt_init(&tdbp->tdb_refcnt);
+ refcnt_init_trace(&tdbp->tdb_refcnt, DT_REFCNT_IDX_TDB);
mtx_init(&tdbp->tdb_mtx, IPL_SOFTNET);
TAILQ_INIT(&tdbp->tdb_policy_head);
Index: sys/refcnt.h
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/sys/refcnt.h,v
retrieving revision 1.6
diff -u -p -r1.6 refcnt.h
--- sys/refcnt.h 16 Mar 2022 14:13:01 -0000 1.6
+++ sys/refcnt.h 21 Apr 2022 21:06:03 -0000
@@ -21,24 +21,30 @@
/*
* Locks used to protect struct members in this file:
+ * I immutable after creation
* a atomic operations
*/
struct refcnt {
unsigned int r_refs; /* [a] reference counter */
+ int r_traceidx; /* [I] index for dt(4) tracing */
};
-#define REFCNT_INITIALIZER() { .r_refs = 1 }
+#define REFCNT_INITIALIZER() { .r_refs = 1, .r_traceidx = 0 }
#ifdef _KERNEL
void refcnt_init(struct refcnt *);
+void refcnt_init_trace(struct refcnt *, int id);
void refcnt_take(struct refcnt *);
int refcnt_rele(struct refcnt *);
void refcnt_rele_wake(struct refcnt *);
void refcnt_finalize(struct refcnt *, const char *);
int refcnt_shared(struct refcnt *);
unsigned int refcnt_read(struct refcnt *);
+
+#define DT_REFCNT_IDX_INPCB 1
+#define DT_REFCNT_IDX_TDB 2
#endif /* _KERNEL */
Index: sys/tracepoint.h
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/sys/tracepoint.h,v
retrieving revision 1.1
diff -u -p -r1.1 tracepoint.h
--- sys/tracepoint.h 21 Jan 2020 16:16:23 -0000 1.1
+++ sys/tracepoint.h 21 Apr 2022 21:06:03 -0000
@@ -25,11 +25,13 @@
#if NDT > 0
#include <dev/dt/dtvar.h>
-#define TRACEPOINT(func, name, args...) DT_STATIC_ENTER(func, name,
args)
+#define TRACEPOINT(func, name, args...) DT_STATIC_ENTER(func, name,
args)
+#define TRACEINDEX(func, index, args...) DT_INDEX_ENTER(func, index, args)
#else /* NDT > 0 */
-#define TRACEPOINT(func, name, args...)
+#define TRACEPOINT(func, name, args...)
+#define TRACEINDEX(func, index, args...)
#endif /* NDT > 0 */
#endif /* _KERNEL */
