aboutsummaryrefslogtreecommitdiff
path: root/kernel/trace/ring_buffer.c
diff options
context:
space:
mode:
authorThomas Gleixner <[email protected]>2018-09-15 20:50:42 +0200
committerThomas Gleixner <[email protected]>2018-09-15 20:50:42 +0200
commit9ac669fc01dbfef707ecaa6b618c0d03294cca16 (patch)
tree3207995766ab5664c60026daae5da268806a3262 /kernel/trace/ring_buffer.c
parentfbfa9260085b5b578a049a90135e5c51928c5f7f (diff)
parent67314ec7b0250290cc85eaa7a2f88a8ddb9e8547 (diff)
Merge tag 'y2038' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground into timers/core
Pull more y2038 work from Arnd Bergman: y2038: convert more syscalls Here is another set of system call changes to prepare the change over to 64-bit time_t. As before, the strategy is to change system calls that take a 'struct timespec' argument over to 'struct __kernel_timespec', which for now is defined to be the same but will get redefined to use a 64-bit time_t argument once we are ready to modify the system call tables. The major change from previous patches is that the plan is no longer to directly use the 'compat' system calls for providing compatibility with the existing 32-bit time_t based entry points. Instead, we rename the compat code to something that makes more sense on 32-bit architectures, e.g. compat_timespec becomes old_timespec32. With the renamed types in place, change over the 'stat' and 'utimes' families of system calls, sched_rr_get_interval, recvmmsg and rt_sigtimedwait. Another series for poll, select and io_pgetevents is currently being tested.
Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c19
1 files changed, 18 insertions, 1 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 6a46af21765c..1d92d4a982fd 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Generic ring buffer
*
@@ -3221,12 +3222,28 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_on);
*
* Returns true if the ring buffer is in a state that it accepts writes.
*/
-int ring_buffer_record_is_on(struct ring_buffer *buffer)
+bool ring_buffer_record_is_on(struct ring_buffer *buffer)
{
return !atomic_read(&buffer->record_disabled);
}
/**
+ * ring_buffer_record_is_set_on - return true if the ring buffer is set writable
+ * @buffer: The ring buffer to see if write is set enabled
+ *
+ * Returns true if the ring buffer is set writable by ring_buffer_record_on().
+ * Note that this does NOT mean it is in a writable state.
+ *
+ * It may return true when the ring buffer has been disabled by
+ * ring_buffer_record_disable(), as that is a temporary disabling of
+ * the ring buffer.
+ */
+bool ring_buffer_record_is_set_on(struct ring_buffer *buffer)
+{
+ return !(atomic_read(&buffer->record_disabled) & RB_BUFFER_OFF);
+}
+
+/**
* ring_buffer_record_disable_cpu - stop all writes into the cpu_buffer
* @buffer: The ring buffer to stop writes to.
* @cpu: The CPU buffer to stop