История изменений
Исправление pon4ik, (текущая версия) :
Чет пишут что глубоко пофиг какой именно тип часов использовать как я понял:
man 7 vdso
One frequently used system call is gettimeofday(2). This system call
is called both directly by user-space applications as well as indirectly by the C library. Think timestamps or timing loops or polling—all of these frequently need to know what time it is right now. This information is also not secret—any application in any privilege mode (root or any unprivileged user) will get the same answer. Thus the kernel arranges for the information required to answer this question to be placed in memory the process can access. Now a call to gettimeofday(2) changes from a system call to a normal function call and a few memory accesses.
Для остального надо читать сорцы конкретного ядра видимо.
Исходная версия pon4ik, :
Чет пишут что глубоко пофиг какой именно тип часов использовать как я понял:
man 7 vdso
One frequently used system call is gettimeofday(2). This system call
is called both directly by user-space applications as well as indirectly by the C library. Think timestamps or timing loops or polling—all of these frequently need to know what time it is right now. This information is also not secret—any application in any privilege mode (root or any unprivileged user) will get the same answer. Thus the kernel arranges for the information required to answer this question to be placed in memory the process can access. Now a call to gettimeofday(2) changes from a system call to a normal function call and a few memory accesses.
Для остального надо читать сорцы конкретного ядра видимо.