GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-19 21:21:09 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

tracing: Have the reg function allow to fail

Browse source 
Some tracepoints have a registration function that gets enabled when the
tracepoint is enabled. There may be cases that the registraction function
must fail (for example, can't allocate enough memory). In this case, the
tracepoint should also fail to register, otherwise the user would not know
why the tracepoint is not working.

Cc: David Howells <dhowells@redhat.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat) 2016-11-28 13:03:21 -05:00 • committed by Steven Rostedt
parent 38e11df134
commit 8cf868affd
15 changed files with 34 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

12
kernel/tracepoint.c
View file

@ -194,9 +194,13 @@ static int tracepoint_add_func(struct tracepoint *tp,
struct tracepoint_func *func, int prio)
{
struct tracepoint_func *old, *tp_funcs;
int ret;
if (tp->regfunc && !static_key_enabled(&tp->key))
tp->regfunc();
if (tp->regfunc && !static_key_enabled(&tp->key)) {
ret = tp->regfunc();
if (ret < 0)
return ret;
}
tp_funcs = rcu_dereference_protected(tp->funcs,
lockdep_is_held(&tracepoints_mutex));
@ -529,7 +533,7 @@ EXPORT_SYMBOL_GPL(for_each_kernel_tracepoint);
/* NB: reg/unreg are called while guarded with the tracepoints_mutex */
static int sys_tracepoint_refcount;
void syscall_regfunc(void)
int syscall_regfunc(void)
{
struct task_struct *p, *t;
@ -541,6 +545,8 @@ void syscall_regfunc(void)
read_unlock(&tasklist_lock);
}
sys_tracepoint_refcount++;
return 0;
}
void syscall_unregfunc(void)