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mm: invoke oom-killer from remaining unconverted page fault handlers

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A few remaining architectures directly kill the page faulting task in an
out of memory situation.  This is usually not a good idea since that
task might not even use a significant amount of memory and so may not be
the optimal victim to resolve the situation.

Since 2.6.29's 1c0fe6e ("mm: invoke oom-killer from page fault") there
is a hook that architecture page fault handlers are supposed to call to
invoke the OOM killer and let it pick the right task to kill.  Convert
the remaining architectures over to this hook.

To have the previous behavior of simply taking out the faulting task the
vm.oom_kill_allocating_task sysctl can be set to 1.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>   [arch/arc bits]
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Johannes Weiner 2013-07-08 15:59:50 -07:00 committed by Linus Torvalds
parent 54f72fe022
commit 609838cfed
6 changed files with 24 additions and 19 deletions
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6
arch/arc/mm/fault.c
View file

@ -207,8 +207,10 @@ out_of_memory:
}
up_read(&mm->mmap_sem);
if (user_mode(regs))
do_group_exit(SIGKILL); /* This will never return */
if (user_mode(regs)) {
pagefault_out_of_memory();
return;
}
goto no_context;

6
arch/metag/mm/fault.c
View file

@ -224,8 +224,10 @@ do_sigbus:
*/
out_of_memory:
up_read(&mm->mmap_sem);
if (user_mode(regs))
do_group_exit(SIGKILL);
if (user_mode(regs)) {
pagefault_out_of_memory();
return 1;
}
no_context:
/* Are we prepared to handle this kernel fault? */

7
arch/mn10300/mm/fault.c
View file

@ -345,9 +345,10 @@ no_context:
*/
out_of_memory:
up_read(&mm->mmap_sem);
printk(KERN_ALERT "VM: killing process %s\n", tsk->comm);
if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR)
do_exit(SIGKILL);
if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) {
pagefault_out_of_memory();
return;
}
goto no_context;
do_sigbus:

8
arch/openrisc/mm/fault.c
View file

@ -267,10 +267,10 @@ out_of_memory:
__asm__ __volatile__("l.nop 1");
up_read(&mm->mmap_sem);
printk("VM: killing process %s\n", tsk->comm);
if (user_mode(regs))
do_exit(SIGKILL);
goto no_context;
if (!user_mode(regs))
goto no_context;
pagefault_out_of_memory();
return;
do_sigbus:
up_read(&mm->mmap_sem);

8
arch/score/mm/fault.c
View file

@ -172,10 +172,10 @@ out_of_memory:
down_read(&mm->mmap_sem);
goto survive;
}
printk("VM: killing process %s\n", tsk->comm);
if (user_mode(regs))
do_group_exit(SIGKILL);
goto no_context;
if (!user_mode(regs))
goto no_context;
pagefault_out_of_memory();
return;
do_sigbus:
up_read(&mm->mmap_sem);

8
arch/tile/mm/fault.c
View file

@ -573,10 +573,10 @@ out_of_memory:
down_read(&mm->mmap_sem);
goto survive;
}
pr_alert("VM: killing process %s\n", tsk->comm);
if (!is_kernel_mode)
do_group_exit(SIGKILL);
goto no_context;
if (is_kernel_mode)
goto no_context;
pagefault_out_of_memory();
return 0;
do_sigbus:
up_read(&mm->mmap_sem);