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Diffstat (limited to 'include/uapi/linux/perf_event.h')
-rw-r--r--include/uapi/linux/perf_event.h27
1 files changed, 17 insertions, 10 deletions
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 40a1fb807396..2fc1602e23bb 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -380,10 +380,13 @@ struct perf_event_mmap_page {
union {
__u64 capabilities;
struct {
- __u64 cap_usr_time : 1,
- cap_usr_rdpmc : 1,
- cap_usr_time_zero : 1,
- cap_____res : 61;
+ __u64 cap_bit0 : 1, /* Always 0, deprecated, see commit 860f085b74e9 */
+ cap_bit0_is_deprecated : 1, /* Always 1, signals that bit 0 is zero */
+
+ cap_user_rdpmc : 1, /* The RDPMC instruction can be used to read counts */
+ cap_user_time : 1, /* The time_* fields are used */
+ cap_user_time_zero : 1, /* The time_zero field is used */
+ cap_____res : 59;
};
};
@@ -442,23 +445,26 @@ struct perf_event_mmap_page {
* ((rem * time_mult) >> time_shift);
*/
__u64 time_zero;
+ __u32 size; /* Header size up to __reserved[] fields. */
/*
* Hole for extension of the self monitor capabilities
*/
- __u64 __reserved[119]; /* align to 1k */
+ __u8 __reserved[118*8+4]; /* align to 1k. */
/*
* Control data for the mmap() data buffer.
*
- * User-space reading the @data_head value should issue an rmb(), on
- * SMP capable platforms, after reading this value -- see
- * perf_event_wakeup().
+ * User-space reading the @data_head value should issue an smp_rmb(),
+ * after reading this value.
*
* When the mapping is PROT_WRITE the @data_tail value should be
- * written by userspace to reflect the last read data. In this case
- * the kernel will not over-write unread data.
+ * written by userspace to reflect the last read data, after issueing
+ * an smp_mb() to separate the data read from the ->data_tail store.
+ * In this case the kernel will not over-write unread data.
+ *
+ * See perf_output_put_handle() for the data ordering.
*/
__u64 data_head; /* head in the data section */
__u64 data_tail; /* user-space written tail */
@@ -528,6 +534,7 @@ enum perf_event_type {
* u64 len;
* u64 pgoff;
* char filename[];
+ * struct sample_id sample_id;
* };
*/
PERF_RECORD_MMAP = 1,