^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * General MIPS MT support routines, usable in AP/SP and SMVP.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2005 Mips Technologies, Inc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) #include <linux/cpu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/cpuset.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/cpumask.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/sched/task.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/cred.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/security.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * CPU mask used to set process affinity for MT VPEs/TCs with FPUs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) cpumask_t mt_fpu_cpumask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) static int fpaff_threshold = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) unsigned long mt_fpemul_threshold;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * Replacement functions for the sys_sched_setaffinity() and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * sys_sched_getaffinity() system calls, so that we can integrate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * FPU affinity with the user's requested processor affinity.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * This code is 98% identical with the sys_sched_setaffinity()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * and sys_sched_getaffinity() system calls, and should be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * updated when kernel/sched/core.c changes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * find_process_by_pid - find a process with a matching PID value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * used in sys_sched_set/getaffinity() in kernel/sched/core.c, so
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * cloned here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) static inline struct task_struct *find_process_by_pid(pid_t pid)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) return pid ? find_task_by_vpid(pid) : current;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) * check the target process has a UID that matches the current process's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) static bool check_same_owner(struct task_struct *p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) const struct cred *cred = current_cred(), *pcred;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) bool match;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) pcred = __task_cred(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) match = (uid_eq(cred->euid, pcred->euid) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) uid_eq(cred->euid, pcred->uid));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) return match;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * mipsmt_sys_sched_setaffinity - set the cpu affinity of a process
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) asmlinkage long mipsmt_sys_sched_setaffinity(pid_t pid, unsigned int len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) unsigned long __user *user_mask_ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) cpumask_var_t cpus_allowed, new_mask, effective_mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) struct thread_info *ti;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) struct task_struct *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) int retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) if (len < sizeof(new_mask))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) if (copy_from_user(&new_mask, user_mask_ptr, sizeof(new_mask)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) get_online_cpus();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) p = find_process_by_pid(pid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) if (!p) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) put_online_cpus();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) return -ESRCH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) /* Prevent p going away */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) get_task_struct(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) retval = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) goto out_put_task;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) retval = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) goto out_free_cpus_allowed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) if (!alloc_cpumask_var(&effective_mask, GFP_KERNEL)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) retval = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) goto out_free_new_mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) if (!check_same_owner(p) && !capable(CAP_SYS_NICE)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) retval = -EPERM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) retval = security_task_setscheduler(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) if (retval)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) /* Record new user-specified CPU set for future reference */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) cpumask_copy(&p->thread.user_cpus_allowed, new_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) again:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) /* Compute new global allowed CPU set if necessary */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) ti = task_thread_info(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) if (test_ti_thread_flag(ti, TIF_FPUBOUND) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) cpumask_intersects(new_mask, &mt_fpu_cpumask)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) cpumask_and(effective_mask, new_mask, &mt_fpu_cpumask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) retval = set_cpus_allowed_ptr(p, effective_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) cpumask_copy(effective_mask, new_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) clear_ti_thread_flag(ti, TIF_FPUBOUND);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) retval = set_cpus_allowed_ptr(p, new_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) if (!retval) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) cpuset_cpus_allowed(p, cpus_allowed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) if (!cpumask_subset(effective_mask, cpus_allowed)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) * We must have raced with a concurrent cpuset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) * update. Just reset the cpus_allowed to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) * cpuset's cpus_allowed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) cpumask_copy(new_mask, cpus_allowed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) goto again;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) free_cpumask_var(effective_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) out_free_new_mask:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) free_cpumask_var(new_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) out_free_cpus_allowed:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) free_cpumask_var(cpus_allowed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) out_put_task:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) put_task_struct(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) put_online_cpus();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) * mipsmt_sys_sched_getaffinity - get the cpu affinity of a process
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) unsigned long __user *user_mask_ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) unsigned int real_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) cpumask_t allowed, mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) int retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) struct task_struct *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) real_len = sizeof(mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) if (len < real_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) get_online_cpus();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) retval = -ESRCH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) p = find_process_by_pid(pid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) if (!p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) retval = security_task_getscheduler(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) if (retval)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) cpumask_or(&allowed, &p->thread.user_cpus_allowed, p->cpus_ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) cpumask_and(&mask, &allowed, cpu_active_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) put_online_cpus();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) if (retval)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) if (copy_to_user(user_mask_ptr, &mask, real_len))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) return real_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) static int __init fpaff_thresh(char *str)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) get_option(&str, &fpaff_threshold);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) __setup("fpaff=", fpaff_thresh);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) * FPU Use Factor empirically derived from experiments on 34K
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) #define FPUSEFACTOR 2000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) static __init int mt_fp_affinity_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) if (fpaff_threshold >= 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) mt_fpemul_threshold = fpaff_threshold;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) mt_fpemul_threshold =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) (FPUSEFACTOR * (loops_per_jiffy/(500000/HZ))) / HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) printk(KERN_DEBUG "FPU Affinity set after %ld emulations\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) mt_fpemul_threshold);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) arch_initcall(mt_fp_affinity_init);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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