| @@ -873,6 +873,113 @@ static const struct file_operations proc_environ_operations = { · 872 unmodified lines |
| 873 | 873 | .release = mem_release, |
| 874 | 874 | }; |
| 875 | 875 | |
| 876 | +static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, |
| 877 | + loff_t *ppos) |
| 878 | +{ |
| 879 | + struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); |
| 880 | + char buffer[PROC_NUMBUF]; |
| 881 | + int oom_adj = OOM_ADJUST_MIN; |
| 882 | + size_t len; |
| 883 | + unsigned long flags; |
| 884 | + |
| 885 | + if (!task) |
| 886 | + return -ESRCH; |
| 887 | + if (lock_task_sighand(task, &flags)) { |
| 888 | + if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) |
| 889 | + oom_adj = OOM_ADJUST_MAX; |
| 890 | + else |
| 891 | + oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / |
| 892 | + OOM_SCORE_ADJ_MAX; |
| 893 | + unlock_task_sighand(task, &flags); |
| 894 | + } |
| 895 | + put_task_struct(task); |
| 896 | + len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); |
| 897 | + return simple_read_from_buffer(buf, count, ppos, buffer, len); |
| 898 | +} |
| 899 | + |
| 900 | +static ssize_t oom_adj_write(struct file *file, const char __user *buf, |
| 901 | + size_t count, loff_t *ppos) |
| 902 | +{ |
| 903 | + struct task_struct *task; |
| 904 | + char buffer[PROC_NUMBUF]; |
| 905 | + int oom_adj; |
| 906 | + unsigned long flags; |
| 907 | + int err; |
| 908 | + |
| 909 | + memset(buffer, 0, sizeof(buffer)); |
| 910 | + if (count > sizeof(buffer) - 1) |
| 911 | + count = sizeof(buffer) - 1; |
| 912 | + if (copy_from_user(buffer, buf, count)) { |
| 913 | + err = -EFAULT; |
| 914 | + goto out; |
| 915 | + } |
| 916 | + |
| 917 | + err = kstrtoint(strstrip(buffer), 0, &oom_adj); |
| 918 | + if (err) |
| 919 | + goto out; |
| 920 | + if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && |
| 921 | + oom_adj != OOM_DISABLE) { |
| 922 | + err = -EINVAL; |
| 923 | + goto out; |
| 924 | + } |
| 925 | + |
| 926 | + task = get_proc_task(file->f_path.dentry->d_inode); |
| 927 | + if (!task) { |
| 928 | + err = -ESRCH; |
| 929 | + goto out; |
| 930 | + } |
| 931 | + |
| 932 | + task_lock(task); |
| 933 | + if (!task->mm) { |
| 934 | + err = -EINVAL; |
| 935 | + goto err_task_lock; |
| 936 | + } |
| 937 | + |
| 938 | + if (!lock_task_sighand(task, &flags)) { |
| 939 | + err = -ESRCH; |
| 940 | + goto err_task_lock; |
| 941 | + } |
| 942 | + |
| 943 | + /* |
| 944 | + * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum |
| 945 | + * value is always attainable. |
| 946 | + */ |
| 947 | + if (oom_adj == OOM_ADJUST_MAX) |
| 948 | + oom_adj = OOM_SCORE_ADJ_MAX; |
| 949 | + else |
| 950 | + oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; |
| 951 | + |
| 952 | + if (oom_adj < task->signal->oom_score_adj && |
| 953 | + !capable(CAP_SYS_RESOURCE)) { |
| 954 | + err = -EACCES; |
| 955 | + goto err_sighand; |
| 956 | + } |
| 957 | + |
| 958 | + /* |
| 959 | + * /proc/pid/oom_adj is provided for legacy purposes, ask users to use |
| 960 | + * /proc/pid/oom_score_adj instead. |
| 961 | + */ |
| 962 | + printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", |
| 963 | + current->comm, task_pid_nr(current), task_pid_nr(task), |
| 964 | + task_pid_nr(task)); |
| 965 | + |
| 966 | + task->signal->oom_score_adj = oom_adj; |
| 967 | + trace_oom_score_adj_update(task); |
| 968 | +err_sighand: |
| 969 | + unlock_task_sighand(task, &flags); |
| 970 | +err_task_lock: |
| 971 | + task_unlock(task); |
| 972 | + put_task_struct(task); |
| 973 | +out: |
| 974 | + return err < 0 ? err : count; |
| 975 | +} |
| 976 | + |
| 977 | +static const struct file_operations proc_oom_adj_operations = { |
| 978 | + .read = oom_adj_read, |
| 979 | + .write = oom_adj_write, |
| 980 | + .llseek = generic_file_llseek, |
| 981 | +}; |
| 982 | + |
| 876 | 983 | static ssize_t oom_score_adj_read(struct file *file, char __user *buf, |
| 877 | 984 | size_t count, loff_t *ppos) |
| 878 | 985 | { |
| @@ -2598,6 +2705,7 @@ static const struct pid_entry tgid_base_stuff[] = { · 1719 unmodified lines |
| 2598 | 2705 | REG("cgroup", S_IRUGO, proc_cgroup_operations), |
| 2599 | 2706 | #endif |
| 2600 | 2707 | INF("oom_score", S_IRUGO, proc_oom_score), |
| 2708 | + REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), |
| 2601 | 2709 | REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), |
| 2602 | 2710 | #ifdef CONFIG_AUDITSYSCALL |
| 2603 | 2711 | REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), |
| @@ -2964,6 +3072,7 @@ static const struct pid_entry tid_base_stuff[] = { · 360 unmodified lines |
| 2964 | 3072 | REG("cgroup", S_IRUGO, proc_cgroup_operations), |
| 2965 | 3073 | #endif |
| 2966 | 3074 | INF("oom_score", S_IRUGO, proc_oom_score), |
| 3075 | + REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), |
| 2967 | 3076 | REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), |
| 2968 | 3077 | #ifdef CONFIG_AUDITSYSCALL |
| 2969 | 3078 | REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), |