1 /* 2 ** Copyright 2007, The Android Open Source Project 3 ** 4 ** Licensed under the Apache License, Version 2.0 (the "License"); 5 ** you may not use this file except in compliance with the License. 6 ** You may obtain a copy of the License at 7 ** 8 ** http://www.apache.org/licenses/LICENSE-2.0 9 ** 10 ** Unless required by applicable law or agreed to in writing, software 11 ** distributed under the License is distributed on an "AS IS" BASIS, 12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 ** See the License for the specific language governing permissions and 14 ** limitations under the License. 15 */ 16 17 #include <errno.h> 18 #include <fcntl.h> 19 #include <stdio.h> 20 #include <stdlib.h> 21 #include <string.h> 22 #include <unistd.h> 23 24 #include <cutils/iosched_policy.h> 25 26 #if defined(__ANDROID__) 27 #define IOPRIO_WHO_PROCESS (1) 28 #define IOPRIO_CLASS_SHIFT (13) 29 #include <sys/syscall.h> 30 #define __android_unused 31 #else 32 #define __android_unused __attribute__((__unused__)) 33 #endif 34 35 int android_set_ioprio(int pid __android_unused, IoSchedClass clazz __android_unused, int ioprio __android_unused) { 36 #if defined(__ANDROID__) 37 if (syscall(SYS_ioprio_set, IOPRIO_WHO_PROCESS, pid, ioprio | (clazz << IOPRIO_CLASS_SHIFT))) { 38 return -1; 39 } 40 #endif 41 return 0; 42 } 43 44 int android_get_ioprio(int pid __android_unused, IoSchedClass *clazz, int *ioprio) { 45 #if defined(__ANDROID__) 46 int rc; 47 48 if ((rc = syscall(SYS_ioprio_get, IOPRIO_WHO_PROCESS, pid)) < 0) { 49 return -1; 50 } 51 52 *clazz = (rc >> IOPRIO_CLASS_SHIFT); 53 *ioprio = (rc & 0xff); 54 #else 55 *clazz = IoSchedClass_NONE; 56 *ioprio = 0; 57 #endif 58 return 0; 59 } 60