1/*
2 Parameters for the Linux kernel ABI for CPU clocks, the bit fields within
3 a clockid:
4
5 - The most significant 29 bits hold either a pid or a file descriptor.
6 - Bit 2 indicates whether a cpu clock refers to a thread or a process.
7 - Bits 1 and 0 give the type: PROF=0, VIRT=1, SCHED=2, or FD=3.
8 - A clockid is invalid if bits 2, 1, and 0 are all set.
9 */
10
11#define CPUCLOCK_PID(clock) ((pid_t) ~((clock) >> 3))
12#define CPUCLOCK_PERTHREAD(clock) \
13 (((clock) & (clockid_t) CPUCLOCK_PERTHREAD_MASK) != 0)
14#define CPUCLOCK_PID_MASK 7
15#define CPUCLOCK_PERTHREAD_MASK 4
16#define CPUCLOCK_WHICH(clock) ((clock) & (clockid_t) CPUCLOCK_CLOCK_MASK)
17#define CPUCLOCK_CLOCK_MASK 3
18#define CPUCLOCK_PROF 0
19#define CPUCLOCK_VIRT 1
20#define CPUCLOCK_SCHED 2
21#define CPUCLOCK_MAX 3
22
23static inline clockid_t
24make_process_cpuclock (unsigned int pid, clockid_t clock)
25{
26 return ((~pid) << 3) | clock;
27}
28
29static inline clockid_t
30make_thread_cpuclock (unsigned int tid, clockid_t clock)
31{
32 return make_process_cpuclock (tid, clock | CPUCLOCK_PERTHREAD_MASK);
33}
34
35#define PROCESS_CLOCK make_process_cpuclock (0, CPUCLOCK_SCHED)
36#define THREAD_CLOCK make_thread_cpuclock (0, CPUCLOCK_SCHED)
37