diff options
Diffstat (limited to 'include/uapi/linux/rseq.h')
| -rw-r--r-- | include/uapi/linux/rseq.h | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/include/uapi/linux/rseq.h b/include/uapi/linux/rseq.h index 1b76d508400c..863c4a00a66b 100644 --- a/include/uapi/linux/rseq.h +++ b/include/uapi/linux/rseq.h @@ -19,13 +19,20 @@ enum rseq_cpu_id_state { }; enum rseq_flags { - RSEQ_FLAG_UNREGISTER = (1 << 0), + RSEQ_FLAG_UNREGISTER = (1 << 0), + RSEQ_FLAG_SLICE_EXT_DEFAULT_ON = (1 << 1), }; enum rseq_cs_flags_bit { + /* Historical and unsupported bits */ RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT = 0, RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT = 1, RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT = 2, + /* (3) Intentional gap to put new bits into a separate byte */ + + /* User read only feature flags */ + RSEQ_CS_FLAG_SLICE_EXT_AVAILABLE_BIT = 4, + RSEQ_CS_FLAG_SLICE_EXT_ENABLED_BIT = 5, }; enum rseq_cs_flags { @@ -35,6 +42,11 @@ enum rseq_cs_flags { (1U << RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT), RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE = (1U << RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT), + + RSEQ_CS_FLAG_SLICE_EXT_AVAILABLE = + (1U << RSEQ_CS_FLAG_SLICE_EXT_AVAILABLE_BIT), + RSEQ_CS_FLAG_SLICE_EXT_ENABLED = + (1U << RSEQ_CS_FLAG_SLICE_EXT_ENABLED_BIT), }; /* @@ -53,6 +65,27 @@ struct rseq_cs { __u64 abort_ip; } __attribute__((aligned(4 * sizeof(__u64)))); +/** + * rseq_slice_ctrl - Time slice extension control structure + * @all: Compound value + * @request: Request for a time slice extension + * @granted: Granted time slice extension + * + * @request is set by user space and can be cleared by user space or kernel + * space. @granted is set and cleared by the kernel and must only be read + * by user space. + */ +struct rseq_slice_ctrl { + union { + __u32 all; + struct { + __u8 request; + __u8 granted; + __u16 __reserved; + }; + }; +}; + /* * struct rseq is aligned on 4 * 8 bytes to ensure it is always * contained within a single cache-line. @@ -142,6 +175,12 @@ struct rseq { __u32 mm_cid; /* + * Time slice extension control structure. CPU local updates from + * kernel and user space. + */ + struct rseq_slice_ctrl slice_ctrl; + + /* * Flexible array member at end of structure, after last feature field. */ char end[]; |