1  /*
       2   * This program is free software; you can redistribute it and/or modify
       3   * it under the terms of the GNU General Public License, version 2, as
       4   * published by the Free Software Foundation
       5   *
       6   * This program is distributed in the hope that it will be useful,
       7   * but WITHOUT ANY WARRANTY; without even the implied warranty of
       8   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
       9   * GNU General Public License for more details.
      10   *
      11   * You should have received a copy of the GNU General Public License along
      12   * with this program; if not, write to the Free Software Foundation, Inc.,
      13   * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
      14   *
      15   * Copyright (C) 2004 Robert Love
      16   * Copyright (C) 2020-2021 Qais Yousef
      17   * Copyright (C) 2020-2021 Arm Ltd
      18   */
      19  #ifndef UTIL_LINUX_SCHED_ATTR_H
      20  #define UTIL_LINUX_SCHED_ATTR_H
      21  
      22  /* the SCHED_BATCH is supported since Linux 2.6.16
      23   *  -- temporary workaround for people with old glibc headers
      24   */
      25  #if defined (__linux__) && !defined(SCHED_BATCH)
      26  # define SCHED_BATCH 3
      27  #endif
      28  
      29  /* the SCHED_IDLE is supported since Linux 2.6.23
      30   * commit id 0e6aca43e08a62a48d6770e9a159dbec167bf4c6
      31   * -- temporary workaround for people with old glibc headers
      32   */
      33  #if defined (__linux__) && !defined(SCHED_IDLE)
      34  # define SCHED_IDLE 5
      35  #endif
      36  
      37  /* flag by sched_getscheduler() */
      38  #if defined(__linux__) && !defined(SCHED_RESET_ON_FORK)
      39  # define SCHED_RESET_ON_FORK 0x40000000
      40  #endif
      41  
      42  /* flag by sched_getattr() */
      43  #if defined(__linux__) && !defined(SCHED_FLAG_RESET_ON_FORK)
      44  # define SCHED_FLAG_RESET_ON_FORK 0x01
      45  #endif
      46  
      47  #if defined(__linux__) && !defined(SCHED_FLAG_RECLAIM)
      48  # define SCHED_FLAG_RECLAIM 0x02
      49  #endif
      50  
      51  #if defined(__linux__) && !defined(SCHED_FLAG_DL_OVERRUN)
      52  # define SCHED_FLAG_DL_OVERRUN 0x04
      53  #endif
      54  
      55  #if defined(__linux__) && !defined(SCHED_FLAG_KEEP_POLICY)
      56  # define SCHED_FLAG_KEEP_POLICY 0x08
      57  #endif
      58  
      59  #if defined(__linux__) && !defined(SCHED_FLAG_KEEP_PARAMS)
      60  # define SCHED_FLAG_KEEP_PARAMS 0x10
      61  #endif
      62  
      63  #if defined(__linux__) && !defined(SCHED_FLAG_UTIL_CLAMP_MIN)
      64  # define SCHED_FLAG_UTIL_CLAMP_MIN 0x20
      65  #endif
      66  
      67  #if defined(__linux__) && !defined(SCHED_FLAG_UTIL_CLAMP_MAX)
      68  # define SCHED_FLAG_UTIL_CLAMP_MAX 0x40
      69  #endif
      70  
      71  #ifdef HAVE_SYS_SYSCALL_H
      72  # include <sys/syscall.h>
      73  #endif
      74  
      75  /* usable kernel-headers, but old glibc-headers */
      76  #if defined (__linux__) && !defined(SYS_sched_setattr) && defined(__NR_sched_setattr)
      77  # define SYS_sched_setattr __NR_sched_setattr
      78  #endif
      79  
      80  #if defined (__linux__) && !defined(SYS_sched_getattr) && defined(__NR_sched_getattr)
      81  # define SYS_sched_getattr __NR_sched_getattr
      82  #endif
      83  
      84  #if defined (__linux__) && !defined(HAVE_SCHED_SETATTR) && defined(SYS_sched_setattr)
      85  # define HAVE_SCHED_SETATTR
      86  
      87  struct sched_attr {
      88  	uint32_t size;
      89  	uint32_t sched_policy;
      90  	uint64_t sched_flags;
      91  
      92  	/* SCHED_NORMAL, SCHED_BATCH */
      93  	int32_t sched_nice;
      94  
      95  	/* SCHED_FIFO, SCHED_RR */
      96  	uint32_t sched_priority;
      97  
      98  	/* SCHED_DEADLINE (nsec) */
      99  	uint64_t sched_runtime;
     100  	uint64_t sched_deadline;
     101  	uint64_t sched_period;
     102  
     103  	/* UTILIZATION CLAMPING */
     104  	uint32_t sched_util_min;
     105  	uint32_t sched_util_max;
     106  };
     107  
     108  static int sched_setattr(pid_t pid, const struct sched_attr *attr, unsigned int flags)
     109  {
     110  	return syscall(SYS_sched_setattr, pid, attr, flags);
     111  }
     112  
     113  static int sched_getattr(pid_t pid, struct sched_attr *attr, unsigned int size, unsigned int flags)
     114  {
     115  	return syscall(SYS_sched_getattr, pid, attr, size, flags);
     116  }
     117  #endif
     118  
     119  /* the SCHED_DEADLINE is supported since Linux 3.14
     120   * commit id aab03e05e8f7e26f51dee792beddcb5cca9215a5
     121   * -- sched_setattr() is required for this policy!
     122   */
     123  #if defined (__linux__) && !defined(SCHED_DEADLINE) && defined(HAVE_SCHED_SETATTR)
     124  # define SCHED_DEADLINE 6
     125  #endif
     126  
     127  #endif /* UTIL_LINUX_SCHED_ATTR_H */