ACPI / PPTT: get PPTT table in the first beginning

Offering: HULK
hulk inclusion
category: bugfix
bugzilla: 174524 https://gitee.com/openeuler/kernel/issues/I4DDEL



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When I added might_sleep() in down_timeout(), I got the following
Calltrace:

[    8.775671] BUG: sleeping function called from invalid context at kernel/locking/semaphore.c:160
[    8.777070] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 14, name: cpuhp/0
[    8.778474] CPU: 0 PID: 14 Comm: cpuhp/0 Not tainted 5.10.0-06616-g1fcfee258bd9-dirty #416
[    8.782067] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
[    8.783452] Call trace:
[    8.783878]  dump_backtrace+0x0/0x1c0
[    8.784512]  show_stack+0x18/0x68
[    8.784976]  dump_stack+0xd8/0x134
[    8.785428]  ___might_sleep+0x108/0x170
[    8.785928]  __might_sleep+0x54/0x90
[    8.786425]  down_timeout+0x30/0x88
[    8.786918]  acpi_os_wait_semaphore+0x70/0xb8
[    8.787483]  acpi_ut_acquire_mutex+0x4c/0xb8
[    8.788016]  acpi_get_table+0x38/0xc4
[    8.788521]  acpi_find_last_cache_level+0x94/0x178
[    8.789088]  _init_cache_level+0xd0/0xe0
[    8.789563]  generic_exec_single+0xa0/0x100
[    8.790122]  smp_call_function_single+0x160/0x1e0
[    8.790714]  init_cache_level+0x38/0x60
[    8.791247]  cacheinfo_cpu_online+0x30/0x898
[    8.791880]  cpuhp_invoke_callback+0x88/0x258
[    8.792707]  cpuhp_thread_fun+0xd8/0x170
[    8.793231]  smpboot_thread_fn+0x194/0x290
[    8.793838]  kthread+0x15c/0x160
[    8.794273]  ret_from_fork+0x10/0x34

It is because generic_exec_single() will disable local irq before
calling _init_cache_level(). _init_cache_level() use acpi_get_table() to
get the PPTT table, but this function could schedule out.

To fix this issue, we use a static pointer to record the mapped PPTT
table in the first beginning. Later, we use that pointer to reference
the PPTT table in acpi_find_last_cache_level(). We also modify other
functions in pptt.c to use the pointer to reference PPTT table.

Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>