From: Robert Richter robert.richter@linaro.org
This new function creates a new fd for an event. We need this later to get a fd from a persistent event.
Signed-off-by: Robert Richter robert.richter@linaro.org Signed-off-by: Robert Richter rric@kernel.org --- kernel/events/core.c | 13 ++++++++----- kernel/events/internal.h | 1 + 2 files changed, 9 insertions(+), 5 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index 24810d5..932acc6 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4100,6 +4100,11 @@ static const struct file_operations perf_fops = { .fasync = perf_fasync, };
+int perf_get_fd(struct perf_event *event) +{ + return anon_inode_getfd("[perf_event]", &perf_fops, event, O_RDWR); +} + /* * Perf event wakeup * @@ -6868,7 +6873,6 @@ SYSCALL_DEFINE5(perf_event_open, struct perf_event *event, *sibling; struct perf_event_attr attr; struct perf_event_context *ctx; - struct file *event_file = NULL; struct fd group = {NULL, 0}; struct task_struct *task = NULL; struct pmu *pmu; @@ -7025,9 +7029,9 @@ SYSCALL_DEFINE5(perf_event_open, goto err_context; }
- event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR); - if (IS_ERR(event_file)) { - err = PTR_ERR(event_file); + event_fd = perf_get_fd(event); + if (event_fd < 0) { + err = event_fd; goto err_context; }
@@ -7093,7 +7097,6 @@ SYSCALL_DEFINE5(perf_event_open, * perf_group_detach(). */ fdput(group); - fd_install(event_fd, event_file); return event_fd;
err_context: diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 8ddaf57..d8708aa 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -192,5 +192,6 @@ static inline void put_event(struct perf_event *event)
extern int perf_alloc_rb(struct perf_event *event, int nr_pages, int flags); extern void perf_free_rb(struct perf_event *event); +extern int perf_get_fd(struct perf_event *event);
#endif /* _KERNEL_EVENTS_INTERNAL_H */