diff options
| author | Christian Borntraeger | 2016-02-02 15:15:56 +0100 |
|---|---|---|
| committer | Christian Borntraeger | 2016-02-10 13:12:57 +0100 |
| commit | 70c88a00fbf65990b6268dabd305113460fe94c1 (patch) | |
| tree | cb7a0222e56da298d207c4003871b1ee6a1f841c /arch/s390 | |
| parent | ab99a1cc7a405fed5148cf6a6fc26eec75b8a7a7 (diff) | |
KVM: s390: do not block CPU on dirty logging
When doing dirty logging on huge guests (e.g.600GB) we sometimes
get rcu stall timeouts with backtraces like
[ 2753.194083] ([<0000000000112fb2>] show_trace+0x12a/0x130)
[ 2753.194092] [<0000000000113024>] show_stack+0x6c/0xe8
[ 2753.194094] [<00000000001ee6a8>] rcu_pending+0x358/0xa48
[ 2753.194099] [<00000000001f20cc>] rcu_check_callbacks+0x84/0x168
[ 2753.194102] [<0000000000167654>] update_process_times+0x54/0x80
[ 2753.194107] [<00000000001bdb5c>] tick_sched_handle.isra.16+0x4c/0x60
[ 2753.194113] [<00000000001bdbd8>] tick_sched_timer+0x68/0x90
[ 2753.194115] [<0000000000182a88>] __run_hrtimer+0x88/0x1f8
[ 2753.194119] [<00000000001838ba>] hrtimer_interrupt+0x122/0x2b0
[ 2753.194121] [<000000000010d034>] do_extint+0x16c/0x170
[ 2753.194123] [<00000000005e206e>] ext_skip+0x38/0x3e
[ 2753.194129] [<000000000012157c>] gmap_test_and_clear_dirty+0xcc/0x118
[ 2753.194134] ([<00000000001214ea>] gmap_test_and_clear_dirty+0x3a/0x118)
[ 2753.194137] [<0000000000132da4>] kvm_vm_ioctl_get_dirty_log+0xd4/0x1b0
[ 2753.194143] [<000000000012ac12>] kvm_vm_ioctl+0x21a/0x548
[ 2753.194146] [<00000000002b57f6>] do_vfs_ioctl+0x30e/0x518
[ 2753.194149] [<00000000002b5a9c>] SyS_ioctl+0x9c/0xb0
[ 2753.194151] [<00000000005e1ae6>] sysc_tracego+0x14/0x1a
[ 2753.194153] [<000003ffb75f3972>] 0x3ffb75f3972
We should do a cond_resched in here.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index d4bcd863b24a..bb99ca28eb66 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -281,6 +281,7 @@ static void kvm_s390_sync_dirty_log(struct kvm *kvm, if (gmap_test_and_clear_dirty(address, gmap)) mark_page_dirty(kvm, cur_gfn); + cond_resched(); } } |