From: Andrea Arcangeli <andrea@suse.de>
iscsi/lvm2/multipath needs guaranteed protection from the oom-killer, so
make the magical value of -17 in /proc/<pid>/oom_adj defeat the oom-killer
altogether.
Signed-off-by: Andrea Arcangeli <andrea@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/fs/proc/base.c | 2 +-
25-akpm/include/linux/mm.h | 3 +++
25-akpm/mm/oom_kill.c | 2 +-
3 files changed, 5 insertions(+), 2 deletions(-)
diff -puN fs/proc/base.c~oom-killer-disable-for-iscsi-lvm2-multipath-userland-critical-sections fs/proc/base.c
--- 25/fs/proc/base.c~oom-killer-disable-for-iscsi-lvm2-multipath-userland-critical-sections 2005-04-02 00:19:01.000000000 -0800
+++ 25-akpm/fs/proc/base.c 2005-04-02 00:19:01.000000000 -0800
@@ -751,7 +751,7 @@ static ssize_t oom_adjust_write(struct f
if (copy_from_user(buffer, buf, count))
return -EFAULT;
oom_adjust = simple_strtol(buffer, &end, 0);
- if (oom_adjust < -16 || oom_adjust > 15)
+ if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE)
return -EINVAL;
if (*end == '\n')
end++;
diff -puN include/linux/mm.h~oom-killer-disable-for-iscsi-lvm2-multipath-userland-critical-sections include/linux/mm.h
--- 25/include/linux/mm.h~oom-killer-disable-for-iscsi-lvm2-multipath-userland-critical-sections 2005-04-02 00:19:01.000000000 -0800
+++ 25-akpm/include/linux/mm.h 2005-04-02 00:19:01.000000000 -0800
@@ -890,5 +890,8 @@ int in_gate_area_no_task(unsigned long a
#define in_gate_area(task, addr) ({(void)task; in_gate_area_no_task(addr);})
#endif /* __HAVE_ARCH_GATE_AREA */
+/* /proc/<pid>/oom_adj set to -17 protects from the oom-killer */
+#define OOM_DISABLE -17
+
#endif /* __KERNEL__ */
#endif /* _LINUX_MM_H */
diff -puN mm/oom_kill.c~oom-killer-disable-for-iscsi-lvm2-multipath-userland-critical-sections mm/oom_kill.c
--- 25/mm/oom_kill.c~oom-killer-disable-for-iscsi-lvm2-multipath-userland-critical-sections 2005-04-02 00:19:01.000000000 -0800
+++ 25-akpm/mm/oom_kill.c 2005-04-02 00:19:01.000000000 -0800
@@ -145,7 +145,7 @@ static struct task_struct * select_bad_p
do_posix_clock_monotonic_gettime(&uptime);
do_each_thread(g, p)
/* skip the init task with pid == 1 */
- if (p->pid > 1) {
+ if (p->pid > 1 && p->oomkilladj != OOM_DISABLE) {
unsigned long points;
/*
_