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Diffstat (limited to 'kernel/perf_event.c')
-rw-r--r--kernel/perf_event.c45
1 files changed, 26 insertions, 19 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index e353be2a38ee..d41909f0edb6 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1417,13 +1417,16 @@ do { \
divisor = nsec * frequency;
}
+ if (!divisor)
+ return dividend;
+
return div64_u64(dividend, divisor);
}
static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count)
{
struct hw_perf_event *hwc = &event->hw;
- u64 period, sample_period;
+ s64 period, sample_period;
s64 delta;
period = perf_calculate_period(event, nsec, count);
@@ -4749,8 +4752,8 @@ SYSCALL_DEFINE5(perf_event_open,
struct perf_event_context *ctx;
struct file *event_file = NULL;
struct file *group_file = NULL;
+ int event_fd;
int fput_needed = 0;
- int fput_needed2 = 0;
int err;
/* for future expandability... */
@@ -4771,12 +4774,18 @@ SYSCALL_DEFINE5(perf_event_open,
return -EINVAL;
}
+ event_fd = get_unused_fd_flags(O_RDWR);
+ if (event_fd < 0)
+ return event_fd;
+
/*
* Get the target context (task or percpu):
*/
ctx = find_get_context(pid, cpu);
- if (IS_ERR(ctx))
- return PTR_ERR(ctx);
+ if (IS_ERR(ctx)) {
+ err = PTR_ERR(ctx);
+ goto err_fd;
+ }
/*
* Look up the group leader (we will attach this event to it):
@@ -4816,13 +4825,11 @@ SYSCALL_DEFINE5(perf_event_open,
if (IS_ERR(event))
goto err_put_context;
- err = anon_inode_getfd("[perf_event]", &perf_fops, event, O_RDWR);
- if (err < 0)
- goto err_free_put_context;
-
- event_file = fget_light(err, &fput_needed2);
- if (!event_file)
+ event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR);
+ if (IS_ERR(event_file)) {
+ err = PTR_ERR(event_file);
goto err_free_put_context;
+ }
if (flags & PERF_FLAG_FD_OUTPUT) {
err = perf_event_set_output(event, group_fd);
@@ -4843,19 +4850,19 @@ SYSCALL_DEFINE5(perf_event_open,
list_add_tail(&event->owner_entry, &current->perf_event_list);
mutex_unlock(&current->perf_event_mutex);
-err_fput_free_put_context:
- fput_light(event_file, fput_needed2);
+ fput_light(group_file, fput_needed);
+ fd_install(event_fd, event_file);
+ return event_fd;
+err_fput_free_put_context:
+ fput(event_file);
err_free_put_context:
- if (err < 0)
- free_event(event);
-
+ free_event(event);
err_put_context:
- if (err < 0)
- put_ctx(ctx);
-
fput_light(group_file, fput_needed);
-
+ put_ctx(ctx);
+err_fd:
+ put_unused_fd(event_fd);
return err;
}