[sched/core] cpuacct_charge() problem

[Pavel V. Panteleev]

Hello!

task_pt_regs() always show on the user regs for user thread, even if 
it's working in kernel mode now. So, index calculation in 
cpuacct_charge() isn't correct and it's always  CPUACCT_STAT_USER for 
user thread. The time, spent in kernel mode for user task, will be lost:

int index = CPUACCT_STAT_SYSTEM;
struct pt_regs *regs = task_pt_regs(tsk);

if (regs && user_mode(regs))
    index = CPUACCT_STAT_USER;