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| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2022-08-30 09:08:02 -0300 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2022-10-20 10:19:08 -0300 |
| commit | 9b5e138f2bbd032da858a4ad5bb51ed99d6f89b6 (patch) | |
| tree | d61137c94c8088bde747b0b6c741c35e0ed22f1a /sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h | |
| parent | 643a2d01399188192e0da234581034f77c892054 (diff) | |
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linux: Avoid shifting a negative signed on POSIX timer interface
The current macros uses pid as signed value, which triggers a compiler
warning for process and thread timers. Replace MAKE_PROCESS_CPUCLOCK
with static inline function that expects the pid as unsigned. These
are similar to what Linux does internally.
Checked on x86_64-linux-gnu.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
Diffstat (limited to 'sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h b/sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h index 164a90ddeb..bea1e0e62d 100644 --- a/sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h +++ b/sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h @@ -1,4 +1,12 @@ -/* Parameters for the Linux kernel ABI for CPU clocks. */ +/* + Parameters for the Linux kernel ABI for CPU clocks, the bit fields within + a clockid: + + - The most significant 29 bits hold either a pid or a file descriptor. + - Bit 2 indicates whether a cpu clock refers to a thread or a process. + - Bits 1 and 0 give the type: PROF=0, VIRT=1, SCHED=2, or FD=3. + - A clockid is invalid if bits 2, 1, and 0 are all set. + */ #define CPUCLOCK_PID(clock) ((pid_t) ~((clock) >> 3)) #define CPUCLOCK_PERTHREAD(clock) \ @@ -12,7 +20,17 @@ #define CPUCLOCK_SCHED 2 #define CPUCLOCK_MAX 3 -#define MAKE_PROCESS_CPUCLOCK(pid, clock) \ - ((~(clockid_t) (pid) << 3) | (clockid_t) (clock)) -#define MAKE_THREAD_CPUCLOCK(tid, clock) \ - MAKE_PROCESS_CPUCLOCK((tid), (clock) | CPUCLOCK_PERTHREAD_MASK) +static inline clockid_t +make_process_cpuclock (unsigned int pid, clockid_t clock) +{ + return ((~pid) << 3) | clock; +} + +static inline clockid_t +make_thread_cpuclock (unsigned int tid, clockid_t clock) +{ + return make_process_cpuclock (tid, clock | CPUCLOCK_PERTHREAD_MASK); +} + +#define PROCESS_CLOCK make_process_cpuclock (0, CPUCLOCK_SCHED) +#define THREAD_CLOCK make_thread_cpuclock (0, CPUCLOCK_SCHED) |