Fix: provide more precise error report for enable event

[lttng-modules.git] / lttng-syscalls.c

diff --git a/lttng-syscalls.c b/lttng-syscalls.c
index 62ed24aa66723c2cb16b8abe2a83cd6b5a8ccb48..3215564161c1c35987a815106b8638e66db0e745 100644 (file)
--- a/lttng-syscalls.c
+++ b/lttng-syscalls.c
@@ -23,6 +23,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/compat.h>
+#include <linux/err.h>
 #include <asm/ptrace.h>
 #include <asm/syscall.h>
 
@@ -322,14 +323,15 @@ int fill_table(const struct trace_syscall_entry *table, size_t table_len,
                ev.instrumentation = LTTNG_KERNEL_NOOP;
                chan_table[i] = lttng_event_create(chan, &ev, filter,
                                                desc);
-               if (!chan_table[i]) {
+               WARN_ON_ONCE(!chan_table[i]);
+               if (IS_ERR(chan_table[i])) {
                        /*
                         * If something goes wrong in event registration
                         * after the first one, we have no choice but to
                         * leave the previous events in there, until
                         * deleted by session teardown.
                         */
-                       return -EINVAL;
+                       return PTR_ERR(chan_table[i]);
                }
        }
        return 0;
@@ -369,8 +371,9 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                ev.instrumentation = LTTNG_KERNEL_NOOP;
                chan->sc_unknown = lttng_event_create(chan, &ev, filter,
                                                    desc);
-               if (!chan->sc_unknown) {
-                       return -EINVAL;
+               WARN_ON_ONCE(!chan->sc_unknown);
+               if (IS_ERR(chan->sc_unknown)) {
+                       return PTR_ERR(chan->sc_unknown);
                }
        }
 
@@ -384,8 +387,9 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                ev.instrumentation = LTTNG_KERNEL_NOOP;
                chan->sc_compat_unknown = lttng_event_create(chan, &ev, filter,
                                                           desc);
-               if (!chan->sc_compat_unknown) {
-                       return -EINVAL;
+               WARN_ON_ONCE(!chan->sc_unknown);
+               if (IS_ERR(chan->sc_compat_unknown)) {
+                       return PTR_ERR(chan->sc_compat_unknown);
                }
        }
 
@@ -399,8 +403,9 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                ev.instrumentation = LTTNG_KERNEL_NOOP;
                chan->sc_exit = lttng_event_create(chan, &ev, filter,
                                                 desc);
-               if (!chan->sc_exit) {
-                       return -EINVAL;
+               WARN_ON_ONCE(!chan->sc_exit);
+               if (IS_ERR(chan->sc_exit)) {
+                       return PTR_ERR(chan->sc_exit);
                }
        }