![]() In show_numa_map() we collect statistics into a numa_maps structure. Since the number of NUMA nodes can be very large, this structure is not a candidate for stack allocation. Instead of going thru a kmalloc()+kfree() cycle each time show_numa_map() is invoked, perform the allocation just once when /proc/pid/numa_maps is opened. Performing the allocation when numa_maps is opened, and thus before a reference to the target tasks mm is taken, eliminates a potential stalemate condition in the oom-killer as originally described by Hugh Dickins: ... imagine what happens if the system is out of memory, and the mm we're looking at is selected for killing by the OOM killer: while we wait in __get_free_page for more memory, no memory is freed from the selected mm because it cannot reach exit_mmap while we hold that reference. Signed-off-by: Stephen Wilson <wilsons@start.ca> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
array.c | ||
base.c | ||
cmdline.c | ||
consoles.c | ||
cpuinfo.c | ||
devices.c | ||
generic.c | ||
inode.c | ||
internal.h | ||
interrupts.c | ||
Kconfig | ||
kcore.c | ||
kmsg.c | ||
loadavg.c | ||
Makefile | ||
meminfo.c | ||
mmu.c | ||
nommu.c | ||
page.c | ||
proc_devtree.c | ||
proc_net.c | ||
proc_sysctl.c | ||
proc_tty.c | ||
root.c | ||
softirqs.c | ||
stat.c | ||
task_mmu.c | ||
task_nommu.c | ||
uptime.c | ||
version.c | ||
vmcore.c |