Revert "watchdog: Fix check_preemption_disabled() error"

hulk inclusion
category: bugfix
bugzilla: 173968, https://gitee.com/openeuler/kernel/issues/I3J87Y


CVE: NA

---------------------------

This reverts commit b2e484e9.

When CONFIG_LOCKDEP and CONFIG_DEBUG_LOCKDEP are enabled, it detects the following error:

[   10.145007] BUG: sleeping function called from invalid context at mm/slab.h:418
[   10.145394] in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0
[   10.145765] Preemption disabled at:
[   10.145978] [<ffff000008f8e7b4>] hardlockup_detector_perf_init+0x20/0x100
[   10.146770] CPU: 6 PID: 1 Comm: swapper/0 Not tainted 4.19.90+ #3
[   10.148242] Hardware name: linux,dummy-virt (DT)
[   10.148572] Call trace:
[   10.148667]  dump_backtrace+0x0/0x190
[   10.148765]  show_stack+0x24/0x30
[   10.148875]  dump_stack+0xa4/0xf8
[   10.148964]  ___might_sleep+0x150/0x180
[   10.149065]  __might_sleep+0x58/0x90
[   10.149199]  kmem_cache_alloc_trace+0x244/0x2b0
[   10.149308]  perf_event_alloc+0x74/0x680
[   10.149402]  perf_event_create_kernel_counter+0x2c/0x190
[   10.149516]  arch_probe_cpu_freq+0x84/0x1ac
[   10.149611]  hw_nmi_get_sample_period+0xb8/0x180
[   10.149713]  hardlockup_detector_event_create+0x28/0xfc
[   10.149827]  hardlockup_detector_perf_init+0x24/0x100
[   10.149943]  watchdog_nmi_probe+0x14/0x1c
[   10.150037]  lockup_detector_init+0x58/0x98
[   10.150173]  kernel_init_freeable+0x10c/0x1c4
[   10.150298]  kernel_init+0x18/0x110
[   10.150422]  ret_from_fork+0x10/0x18

In 'b2e484e9 ("watchdog: Fix check_preemption_disabled() error")', we
tried to fix check_preemption_disabled() error by disabling preemption in
hardlockup_detector_perf_init(), but missed that function
perf_event_create_kernel_counter() may sleep.

The preemption is always disabled, the problem that wanted be fixed is not
existed, so just revert this commit.

Fixes: b2e484e9 ("watchdog: Fix check_preemption_disabled() error")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>