●●● ●●●● 6.2 The Critical-Section Problem::: ●●●● ● Preemptive kernels ●●●● Be carefully designed to ensure that shared kernel data are free from race conditions Be especially difficult to design for SMP Solaris、IRX、 Linux(26 or later) The advantage of preemptive kernels Be more suitable for real-time programming May be more responsive, since there is less risk that a kernel-mode process will run for an arbitrarily long period17 6.2 The Critical-Section Problem ⚫ Preemptive kernels ▪ Be carefully designed to ensure that shared kernel data are free from race conditions ▪ Be especially difficult to design for SMP ▪ Solaris、IRIX、Linux (2.6 or later) ▪ The advantage of preemptive kernels ▪ Be more suitable for real-time programming ▪ May be more responsive, since there is less risk that a kernel-mode process will run for an arbitrarily long period