lkml.org 
[lkml]   [2000]   [Nov]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] Re: Negative scalability by removal of lock_kernel()?(Was: Strange performance behavior of 2.4.0-test9)
kumon@flab.fujitsu.co.jp writes:
> Your last patch makes the problem very clear.
>
> 2.4.0-test10-pre5 with the LIFO patch (P3), we can't get the values.

It dies at the following line in kernel/sched.c:schedule()

move_rr_back:

switch (prev->state & ~TASK_EXCLUSIVE) {
case TASK_INTERRUPTIBLE:
if (signal_pending(prev)) {
prev->state = TASK_RUNNING;
break;
}
default:
here==> del_from_runqueue(prev);
case TASK_RUNNING:
}


"prev" contains a run_list structure and prev->run_list.next pointed
to NULL. This caused the bus-error in __list_del().

# actually the CPU accesses address 0x4 (4 is offset to prev within
# run_list).

BTW, why this switch statement has less breaks at everywhere.

--
Computer Systems Laboratory, Fujitsu Labs.
kumon@flab.fujitsu.co.jp
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:45    [W:0.231 / U:0.300 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site