Remove support for in-kernel filters.

This might be added back in a future if copying events to userland becomes
a performance issue.  However note that it is not always possible to filter
in-kernel if, for example. a variable has to be evaluated when a rule fires.

diff --git a/usr.sbin/btrace/bt_parse.y b/usr.sbin/btrace/bt_parse.y
index 44f4204..6a4aa5d 100644 (file)
--- a/usr.sbin/btrace/bt_parse.y
+++ b/usr.sbin/btrace/bt_parse.y
@@ -1,4 +1,4 @@
-/*     $OpenBSD: bt_parse.y,v 1.29 2021/04/21 10:53:17 mpi Exp $       */
+/*     $OpenBSD: bt_parse.y,v 1.30 2021/04/22 09:36:39 mpi Exp $       */
 
 /*
  * Copyright (c) 2019-2021 Martin Pieuchot <mpi@openbsd.org>
@@ -58,7 +58,6 @@ SLIST_HEAD(, bt_var)  l_variables;
 
 struct bt_rule *br_new(struct bt_probe *, struct bt_filter *, struct bt_stmt *,
                     enum bt_rtype);
-struct bt_filter *bf_new(enum bt_argtype, enum bt_filtervar, int);
 struct bt_probe        *bp_new(const char *, const char *, const char *, int32_t);
 struct bt_arg  *ba_append(struct bt_arg *, struct bt_arg *);
 struct bt_arg  *ba_op(enum bt_argtype, struct bt_arg *, struct bt_arg *);
@@ -121,7 +120,7 @@ static int pflag;
 
 %type  <v.string>      gvar lvar
 %type  <v.number>      staticval
-%type  <v.i>           fval testop binop builtin
+%type  <v.i>           testop binop builtin
 %type  <v.i>           BUILTIN F_DELETE F_PRINT FUNC0 FUNC1 FUNCN OP1 OP4
 %type  <v.i>           MOP0 MOP1
 %type  <v.probe>       probe probename
@@ -156,11 +155,6 @@ probename  : STRING ':' STRING ':' STRING  { $$ = bp_new($1, $3, $5, 0); }
                | STRING ':' HZ ':' NUMBER      { $$ = bp_new($1, "hz", NULL, $5); }
                ;
 
-
-fval           : PID                           { $$ = B_FV_PID; }
-               | TID                           { $$ = B_FV_TID; }
-               ;
-
 testop         : OP_EQ                         { $$ = B_AT_OP_EQ; }
                | OP_NE                         { $$ = B_AT_OP_NE; }
                | OP_LE                         { $$ = B_AT_OP_LE; }
@@ -301,25 +295,6 @@ br_new(struct bt_probe *probe, struct bt_filter *filter, struct bt_stmt *head,
        return br;
 }
 
-/* Create a new event filter */
-struct bt_filter *
-bf_new(enum bt_argtype op, enum bt_filtervar var, int val)
-{
-       struct bt_filter *bf;
-
-       if (val < 0 || val > INT_MAX)
-               errx(1, "invalid pid '%d'", val);
-
-       bf = calloc(1, sizeof(*bf));
-       if (bf == NULL)
-               err(1, "bt_filter: calloc");
-       bf->bf_evtfilter.bf_op = op;
-       bf->bf_evtfilter.bf_var = var;
-       bf->bf_evtfilter.bf_val = val;
-
-       return bf;
-}
-
 /* Create a new condition */
 struct bt_filter *
 bc_new(struct bt_arg *term, enum bt_argtype op, struct bt_arg *ba)

diff --git a/usr.sbin/btrace/bt_parser.h b/usr.sbin/btrace/bt_parser.h
index 3181ab7..7ebacf6 100644 (file)
--- a/usr.sbin/btrace/bt_parser.h
+++ b/usr.sbin/btrace/bt_parser.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: bt_parser.h,v 1.15 2021/04/21 10:28:54 mpi Exp $      */
+/*     $OpenBSD: bt_parser.h,v 1.16 2021/04/22 09:36:39 mpi Exp $      */
 
 /*
  * Copyright (c) 2019-2021 Martin Pieuchot <mpi@openbsd.org>
@@ -59,12 +59,10 @@ struct bt_evtfilter {
  * Filters, also known as predicates, describe under which set of
  * conditions a rule is executed.
  *
- * Depending on their type they are performed in-kernel or when a rule
- * is evaluated.  In the first case they might prevent the recording of
- * events, in the second case events might be discarded at runtime.
+ * They are performed when a rule is evaluated and events might be
+ * discarded at runtime.
  */
 struct bt_filter {
-       struct bt_evtfilter       bf_evtfilter; /* in-kernel event filter */
        struct bt_stmt           *bf_condition; /* per event condition */
 };
 

diff --git a/usr.sbin/btrace/btrace.c b/usr.sbin/btrace/btrace.c
index 4a61763..9720e0e 100644 (file)
--- a/usr.sbin/btrace/btrace.c
+++ b/usr.sbin/btrace/btrace.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: btrace.c,v 1.34 2021/04/21 13:23:56 jmc Exp $ */
+/*     $OpenBSD: btrace.c,v 1.35 2021/04/22 09:36:39 mpi Exp $ */
 
 /*
  * Copyright (c) 2019 - 2020 Martin Pieuchot <mpi@openbsd.org>
@@ -386,31 +386,6 @@ rules_do(int fd)
        }
 }
 
-static inline enum dt_operand
-dop2dt(enum bt_argtype op)
-{
-       switch (op) {
-       case B_AT_OP_EQ:        return DT_OP_EQ;
-       case B_AT_OP_NE:        return DT_OP_NE;
-       default:        break;
-       }
-       xabort("unknown operand %d", op);
-}
-
-
-static inline enum dt_filtervar
-dvar2dt(enum bt_filtervar var)
-{
-       switch (var) {
-       case B_FV_PID:  return DT_FV_PID;
-       case B_FV_TID:  return DT_FV_TID;
-       case B_FV_NONE: return DT_FV_NONE;
-       default:        break;
-       }
-       xabort("unknown filter %d", var);
-}
-
-
 void
 rules_setup(int fd)
 {
@@ -445,14 +420,6 @@ rules_setup(int fd)
 
                r->br_pbn = dtpi->dtpi_pbn;
                dtrq->dtrq_pbn = dtpi->dtpi_pbn;
-               if (r->br_filter != NULL &&
-                   r->br_filter->bf_condition == NULL) {
-                       struct bt_evtfilter *df = &r->br_filter->bf_evtfilter;
-
-                       dtrq->dtrq_filter.dtf_operand = dop2dt(df->bf_op);
-                       dtrq->dtrq_filter.dtf_variable = dvar2dt(df->bf_var);
-                       dtrq->dtrq_filter.dtf_value = df->bf_val;
-               }
                dtrq->dtrq_rate = r->br_probe->bp_rate;
 
                SLIST_FOREACH(bs, &r->br_action, bs_next) {
@@ -1407,50 +1374,19 @@ debugx(const char *fmt, ...)
        va_end(ap);
 }
 
-static inline const char *
-debug_getfiltervar(struct bt_evtfilter *df)
-{
-       switch (df->bf_var) {
-       case B_FV_PID:  return "pid";
-       case B_FV_TID:  return "tid";
-       case B_FV_NONE: return "";
-       default:
-               xabort("invalid filtervar %d", df->bf_var);
-       }
-}
-
-static inline const char *
-debug_getfilterop(struct bt_evtfilter *df)
-{
-       switch (df->bf_op) {
-       case B_AT_OP_EQ:        return "==";
-       case B_AT_OP_NE:        return "!=";
-       default:
-               xabort("invalid operand %d", df->bf_op);
-       }
-}
-
 void
 debug_dump_filter(struct bt_rule *r)
 {
        if (r->br_filter != NULL) {
                struct bt_stmt *bs = r->br_filter->bf_condition;
+               struct bt_arg *bop = SLIST_FIRST(&bs->bs_args);
+               struct bt_arg *a, *b;
 
-               if (bs == NULL) {
-                       struct bt_evtfilter *df = &r->br_filter->bf_evtfilter;
+               a = bop->ba_value;
+               b = SLIST_NEXT(a, ba_next);
 
-                       debugx(" / %s %s %u /", debug_getfiltervar(df),
-                           debug_getfilterop(df), df->bf_val);
-               } else {
-                       struct bt_arg *bop = SLIST_FIRST(&bs->bs_args);
-                       struct bt_arg *a, *b;
-
-                       a = bop->ba_value;
-                       b = SLIST_NEXT(a, ba_next);
-
-                       debugx(" / %s %s %s /", ba_name(a), ba_name(bop),
-                           (b != NULL) ? ba_name(b) : "NULL");
-               }
+               debugx(" / %s %s %s /", ba_name(a), ba_name(bop),
+                   (b != NULL) ? ba_name(b) : "NULL");
        }
        debugx("\n");
 }