pub const perf_event_mmap_page = extern structpub const perf_event_mmap_page = extern struct {
/// Version number of this struct
version: u32,
/// Lowest version this is compatible with
compt_version: u32,
/// Seqlock for synchronization
lock: u32,
/// Hardware counter identifier
index: u32,
/// Add to hardware counter value
offset: i64,
/// Time the event was active
time_enabled: u64,
/// Time the event was running
time_running: u64,
capabilities: packed struct(u64) {
/// If kernel version < 3.12
/// this rapresents both user_rdpmc and user_time (user_rdpmc | user_time)
/// otherwise deprecated.
bit0: bool,
/// Set if bit0 is deprecated
bit0_is_deprecated: bool,
/// Hardware support for userspace read of performance counters
user_rdpmc: bool,
/// Hardware support for a constant non stop timestamp counter (Eg. TSC on x86)
user_time: bool,
/// The time_zero field is used
user_time_zero: bool,
/// The time_{cycle,mask} fields are used
user_time_short: bool,
____res: u58,
},
/// If capabilities.user_rdpmc
/// this field reports the bit-width of the value read with rdpmc() or equivalent
pcm_width: u16,
/// If capabilities.user_time the following fields can be used to compute the time
/// delta since time_enabled (in ns) using RDTSC or similar
time_shift: u16,
time_mult: u32,
time_offset: u64,
/// If capabilities.user_time_zero the hardware clock can be calculated from
/// sample timestamps
time_zero: u64,
/// Header size
size: u32,
__reserved_1: u32,
/// The following fields are used to compute the timestamp when the hardware clock
/// is less than 64bit wide
time_cycles: u64,
time_mask: u64,
__reserved: [116 * 8]u8,
/// Head in the data section
data_head: u64,
/// Userspace written tail
data_tail: u64,
/// Where the buffer starts
data_offset: u64,
/// Data buffer size
data_size: u64,
// if aux is used, head in the data section
aux_head: u64,
// if aux is used, userspace written tail
aux_tail: u64,
// if aux is used, where the buffer starts
aux_offset: u64,
// if aux is used, data buffer size
aux_size: u64,
}