Build error on cpus_allowed/cpus_mask with kernel 4.18.0-240.1.1

[davidjkcho]

Building xpmem failed with below error using kernel 4.18.0-240.1.1 on CentOS 8.3.

kernel/xpmem_pfn.c:255:25: error: 'struct task_struct' has no member named 'cpus_allowed'; did you mean 'nr_cpus_allowed'?
saved_mask = current->cpus_allowed;
^~~~~~~~~~~~

Below if statement in kernel/xpmem_pfn.c was checking for kernel version for 5.3.0-x or newer to use cpus_mask.
However, kernel 4.18.0-240.1.1 on CentOS 8.3 introduced "RH_KABI_RENAME(cpumask_t cpus_allowed, cpumask_t cpus_mask);" in /usr/src/kernels/4.18.0-240.1.1.el8_3.x86_64/include/linux/sched.h and cpus_mask had to be used instead of cpus_allowed.
Thus it failed to compile.

#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 3, 0)
saved_mask = current->cpus_mask;
#else
saved_mask = current->cpus_allowed;
#endif

[ravitejak07]

As a work around, I have added below code.

#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 3, 0)
saved_mask = current->cpus_mask;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 18, 0)
saved_mask = current->cpus_mask;
#else
saved_mask = current-> cpus_allowed;
#endif