Re: [PATCH v6] ACPI: explicit init HEST, SDEI and GHES in apci_init

Shuai Xue
2022-01-21T03:45:00Z

Hi, Bjorn,

Thank you for your comments.

在 2022/1/21 AM12:22, Bjorn Helgaas 写道:
> On Thu, Jan 20, 2022 at 01:05:22PM +0800, Shuai Xue wrote:
>> From commit e147133a42cb ("ACPI / APEI: Make hest.c manage the estatus
>> memory pool") was merged, ghes_init() relies on acpi_hest_init() to manage
>> the estatus memory pool. On the other hand, ghes_init() relies on
>> sdei_init() to detect the SDEI version and (un)register events. The
>> dependencies are as follows:
>>
>> ghes_init() => acpi_hest_init() => acpi_bus_init() => acpi_init()
>> ghes_init() => sdei_init()
>>
>> HEST is not PCI-specific and initcall ordering is implicit and not
>> well-defined within a level.
>>
>> Based on above, remove acpi_hest_init() from acpi_pci_root_init() and
>> convert ghes_init() and sdei_init() from initcalls to explicit calls in the
>> following order:
>>
>> acpi_hest_init()
>> sdei_init()
>> ghes_init()
>>
>> Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
>
> I didn't suggest the approach; I just reviewed the patch and the
> commit log and proposed moving it out of acpi_pci_root_init(). That
> doesn't need to be acknowledged.

I will delete it in next version :)

>> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
>
> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>

Will add this in next version.

> Minor extra "return" below.
>> ---
>> drivers/acpi/apei/ghes.c | 17 +++++++----------
>> drivers/acpi/bus.c | 4 ++++
>> drivers/acpi/pci_root.c | 3 ---
>> drivers/firmware/arm_sdei.c | 13 ++-----------
>> include/acpi/apei.h | 4 +++-
>> include/linux/arm_sdei.h | 2 ++
>> 6 files changed, 18 insertions(+), 25 deletions(-)
>>
>> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
>> index 0c5c9acc6254..bed4f10cfcb8 100644
>> --- a/drivers/acpi/apei/ghes.c
>> +++ b/drivers/acpi/apei/ghes.c
>> @@ -1457,33 +1457,33 @@ static struct platform_driver ghes_platform_driver = {
>> .remove = ghes_remove,
>> };
>>
>> -static int __init ghes_init(void)
>> +void __init ghes_init(void)
>> {
>> int rc;
>>
>> if (acpi_disabled)
>> - return -ENODEV;
>> + return;
>>
>> switch (hest_disable) {
>> case HEST_NOT_FOUND:
>> - return -ENODEV;
>> + return;
>> case HEST_DISABLED:
>> pr_info(GHES_PFX "HEST is not enabled!\n");
>> - return -EINVAL;
>> + return;
>> default:
>> break;
>> }
>>
>> if (ghes_disable) {
>> pr_info(GHES_PFX "GHES is not enabled!\n");
>> - return -EINVAL;
>> + return;
>> }
>>
>> ghes_nmi_init_cxt();
>>
>> rc = platform_driver_register(&ghes_platform_driver);
>> if (rc)
>> - goto err;
>> + return;
>>
>> rc = apei_osc_setup();
>> if (rc == 0 && osc_sb_apei_support_acked)
>> @@ -1495,8 +1495,5 @@ static int __init ghes_init(void)
>> else
>> pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n");
>>
>> - return 0;
>> -err:
>> - return rc;
>> + return;
>
> Unnecessary "return".

Will fix it in next version.

>
>> }
>> -device_initcall(ghes_init);
>> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
>> index 07f604832fd6..1dcd71df2cd5 100644
>> --- a/drivers/acpi/bus.c
>> +++ b/drivers/acpi/bus.c
>> @@ -30,6 +30,7 @@
>> #include <linux/acpi_viot.h>
>> #include <linux/pci.h>
>> #include <acpi/apei.h>
>> +#include <linux/arm_sdei.h>
>
> This "arm" looks a little out of place in this supposedly arch-generic
> code. Not really a new thing with this patch, since this #include
> already appears in drivers/acpi/apei/ghes.c. Maybe it's unavoidable.

Yep, should we move sdei_init() into the beginning of ghes_init()?

> sdei_init() and ghes_init() stick out here because they're the only
> functions without an "acpi_" prefix. Maybe a separate patch to rename
> them?

Sorry, I forgot to send a patch to rename them. I have a question about this.

> Software Delegated Exception Interface (|SDEI|) is an Arm specification for
> Non-secure world to register handlers with firmware to receive notifications
> about system events.
> LINK: https://github.com/ARM-software/arm-trusted-firmware/blob/master/docs/components/sdei.rst

I think SDEI is not a ACPI Specification but Arm specification so we should
not rename sdei_init() with an "acpi_" prefix. If we move sdei_init() into
ghes_init(), and rename ghes_init() to acpi_ghes_init(), then all looks
fine? What's your opinion, Bjorn?

Best Regards.

Shuai

>
>> #include <linux/suspend.h>
>> #include <linux/prmt.h>
>>
>> @@ -1331,6 +1332,9 @@ static int __init acpi_init(void)
>>
>> pci_mmcfg_late_init();
>> acpi_iort_init();
>> + acpi_hest_init();
>> + sdei_init();
>> + ghes_init();
>> acpi_scan_init();
>> acpi_ec_init();
>> acpi_debugfs_init();
>> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
>> index b76db99cced3..6f9e75d14808 100644
>> --- a/drivers/acpi/pci_root.c
>> +++ b/drivers/acpi/pci_root.c
>> @@ -22,8 +22,6 @@
>> #include <linux/slab.h>
>> #include <linux/dmi.h>
>> #include <linux/platform_data/x86/apple.h>
>> -#include <acpi/apei.h> /* for acpi_hest_init() */
>> -
>> #include "internal.h"
>>
>> #define ACPI_PCI_ROOT_CLASS "pci_bridge"
>> @@ -943,7 +941,6 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>>
>> void __init acpi_pci_root_init(void)
>> {
>> - acpi_hest_init();
>> if (acpi_pci_disabled)
>> return;
>>
>> diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
>> index a7e762c352f9..1e1a51510e83 100644
>> --- a/drivers/firmware/arm_sdei.c
>> +++ b/drivers/firmware/arm_sdei.c
>> @@ -1059,14 +1059,14 @@ static bool __init sdei_present_acpi(void)
>> return true;
>> }
>>
>> -static int __init sdei_init(void)
>> +void __init sdei_init(void)
>> {
>> struct platform_device *pdev;
>> int ret;
>>
>> ret = platform_driver_register(&sdei_driver);
>> if (ret || !sdei_present_acpi())
>> - return ret;
>> + return;
>>
>> pdev = platform_device_register_simple(sdei_driver.driver.name,
>> 0, NULL, 0);
>> @@ -1076,17 +1076,8 @@ static int __init sdei_init(void)
>> pr_info("Failed to register ACPI:SDEI platform device %d\n",
>> ret);
>> }
>> -
>> - return ret;
>> }
>>
>> -/*
>> - * On an ACPI system SDEI needs to be ready before HEST:GHES tries to register
>> - * its events. ACPI is initialised from a subsys_initcall(), GHES is initialised
>> - * by device_initcall(). We want to be called in the middle.
>> - */
>> -subsys_initcall_sync(sdei_init);
>> -
>> int sdei_event_handler(struct pt_regs *regs,
>> struct sdei_registered_event *arg)
>> {
>> diff --git a/include/acpi/apei.h b/include/acpi/apei.h
>> index ece0a8af2bae..4e60dd73c3bb 100644
>> --- a/include/acpi/apei.h
>> +++ b/include/acpi/apei.h
>> @@ -27,14 +27,16 @@ extern int hest_disable;
>> extern int erst_disable;
>> #ifdef CONFIG_ACPI_APEI_GHES
>> extern bool ghes_disable;
>> +void __init ghes_init(void);
>> #else
>> #define ghes_disable 1
>> +static inline void ghes_init(void) { }
>> #endif
>>
>> #ifdef CONFIG_ACPI_APEI
>> void __init acpi_hest_init(void);
>> #else
>> -static inline void acpi_hest_init(void) { return; }
>> +static inline void acpi_hest_init(void) { }
>> #endif
>>
>> int erst_write(const struct cper_record_header *record);
>> diff --git a/include/linux/arm_sdei.h b/include/linux/arm_sdei.h
>> index 0a241c5c911d..14dc461b0e82 100644
>> --- a/include/linux/arm_sdei.h
>> +++ b/include/linux/arm_sdei.h
>> @@ -46,9 +46,11 @@ int sdei_unregister_ghes(struct ghes *ghes);
>> /* For use by arch code when CPU hotplug notifiers are not appropriate. */
>> int sdei_mask_local_cpu(void);
>> int sdei_unmask_local_cpu(void);
>> +void __init sdei_init(void);
>> #else
>> static inline int sdei_mask_local_cpu(void) { return 0; }
>> static inline int sdei_unmask_local_cpu(void) { return 0; }
>> +static inline void sdei_init(void) { }
>> #endif /* CONFIG_ARM_SDE_INTERFACE */
>>
>>
>> --
>> 2.20.1.12.g72788fdb
>>
>>
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