Re: [PATCH v4 6/6] powerpc/fadump: sysfs for fadump memory reservation
On 12/6/19 6:18 PM, Greg KH wrote:
> On Fri, Dec 06, 2019 at 05:54:34PM +0530, Sourabh Jain wrote:
>> Add a sys interface to allow querying the memory reserved by FADump for
>> saving the crash dump.
>>
>> Also added Documentation/ABI for the new sysfs file.
>>
>> Signed-off-by: Sourabh Jain
>> ---
>> Documentation/ABI/testing/sysfs-kernel-fadump| 7 +++
>> Documentation/powerpc/firmware-assisted-dump.rst | 5 +
>> arch/powerpc/kernel/fadump.c | 15 +++
>> 3 files changed, 27 insertions(+)
>>
>> diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump
>> b/Documentation/ABI/testing/sysfs-kernel-fadump
>> index 5d988b919e81..8f7a64a81783 100644
>> --- a/Documentation/ABI/testing/sysfs-kernel-fadump
>> +++ b/Documentation/ABI/testing/sysfs-kernel-fadump
>> @@ -31,3 +31,10 @@ Description: write only
>> the system is booted to capture the vmcore using FADump.
>> It is used to release the memory reserved by FADump to
>> save the crash dump.
>> +
>> +What: /sys/kernel/fadump/mem_reserved
>> +Date: Dec 2019
>> +Contact:linuxppc-dev@lists.ozlabs.org
>> +Description:read only
>> +Provide information about the amount of memory reserved by
>> +FADump to save the crash dump in bytes.
>> diff --git a/Documentation/powerpc/firmware-assisted-dump.rst
>> b/Documentation/powerpc/firmware-assisted-dump.rst
>> index 365c10209ef3..04993eaf3113 100644
>> --- a/Documentation/powerpc/firmware-assisted-dump.rst
>> +++ b/Documentation/powerpc/firmware-assisted-dump.rst
>> @@ -268,6 +268,11 @@ Here is the list of files under kernel sysfs:
>> be handled and vmcore will not be captured. This interface can be
>> easily integrated with kdump service start/stop.
>>
>> + /sys/kernel/fadump/mem_reserved
>> +
>> + This is used to display the memory reserved by FADump for saving the
>> + crash dump.
>> +
>> /sys/kernel/fadump_release_mem
>> This file is available only when FADump is active during
>> second kernel. This is used to release the reserved memory
>> diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
>> index 41a3cda81791..b2af51b7c750 100644
>> --- a/arch/powerpc/kernel/fadump.c
>> +++ b/arch/powerpc/kernel/fadump.c
>> @@ -1357,6 +1357,13 @@ static ssize_t fadump_enabled_show(struct kobject
>> *kobj,
>> return sprintf(buf, "%d\n", fw_dump.fadump_enabled);
>> }
>>
>> +static ssize_t fadump_mem_reserved_show(struct kobject *kobj,
>> +struct kobj_attribute *attr,
>> +char *buf)
>> +{
>> +return sprintf(buf, "%ld\n", fw_dump.reserve_dump_area_size);
>> +}
>> +
>> static ssize_t fadump_register_show(struct kobject *kobj,
>> struct kobj_attribute *attr,
>> char *buf)
>> @@ -1430,6 +1437,10 @@ static struct kobj_attribute enable_attr =
>> __ATTR(enabled,
>> static struct kobj_attribute register_attr = __ATTR(registered,
>> 0644, fadump_register_show,
>> fadump_register_store);
>> +static struct kobj_attribute mem_reserved_attr = __ATTR(mem_reserved,
>> +0444, fadump_mem_reserved_show,
>> +NULL);
>
> __ATTRI_RO()?
>
>> +
>>
>> DEFINE_SHOW_ATTRIBUTE(fadump_region);
>>
>> @@ -1464,6 +1475,10 @@ static void fadump_init_files(void)
>> pr_err("unable to create release_mem sysfs file (%d)\n",
>> rc);
>> }
>> +rc = sysfs_create_file(fadump_kobj, _reserved_attr.attr);
>> +if (rc)
>> +pr_err("unable to create mem_reserved sysfs file (%d)\n",
>> + rc);
>
> Again, put it in an attribute group, that would have only required one
> line, and not this mess of not cleaning up if something went wrong.
Will make the changes accordingly.
Thanks,
Sourabh Jain
Re: [PATCH v4 6/6] powerpc/fadump: sysfs for fadump memory reservation
On Fri, Dec 06, 2019 at 05:54:34PM +0530, Sourabh Jain wrote:
> Add a sys interface to allow querying the memory reserved by FADump for
> saving the crash dump.
>
> Also added Documentation/ABI for the new sysfs file.
>
> Signed-off-by: Sourabh Jain
> ---
> Documentation/ABI/testing/sysfs-kernel-fadump| 7 +++
> Documentation/powerpc/firmware-assisted-dump.rst | 5 +
> arch/powerpc/kernel/fadump.c | 15 +++
> 3 files changed, 27 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump
> b/Documentation/ABI/testing/sysfs-kernel-fadump
> index 5d988b919e81..8f7a64a81783 100644
> --- a/Documentation/ABI/testing/sysfs-kernel-fadump
> +++ b/Documentation/ABI/testing/sysfs-kernel-fadump
> @@ -31,3 +31,10 @@ Description: write only
> the system is booted to capture the vmcore using FADump.
> It is used to release the memory reserved by FADump to
> save the crash dump.
> +
> +What:/sys/kernel/fadump/mem_reserved
> +Date:Dec 2019
> +Contact: linuxppc-dev@lists.ozlabs.org
> +Description: read only
> + Provide information about the amount of memory reserved by
> + FADump to save the crash dump in bytes.
> diff --git a/Documentation/powerpc/firmware-assisted-dump.rst
> b/Documentation/powerpc/firmware-assisted-dump.rst
> index 365c10209ef3..04993eaf3113 100644
> --- a/Documentation/powerpc/firmware-assisted-dump.rst
> +++ b/Documentation/powerpc/firmware-assisted-dump.rst
> @@ -268,6 +268,11 @@ Here is the list of files under kernel sysfs:
> be handled and vmcore will not be captured. This interface can be
> easily integrated with kdump service start/stop.
>
> + /sys/kernel/fadump/mem_reserved
> +
> + This is used to display the memory reserved by FADump for saving the
> + crash dump.
> +
> /sys/kernel/fadump_release_mem
> This file is available only when FADump is active during
> second kernel. This is used to release the reserved memory
> diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
> index 41a3cda81791..b2af51b7c750 100644
> --- a/arch/powerpc/kernel/fadump.c
> +++ b/arch/powerpc/kernel/fadump.c
> @@ -1357,6 +1357,13 @@ static ssize_t fadump_enabled_show(struct kobject
> *kobj,
> return sprintf(buf, "%d\n", fw_dump.fadump_enabled);
> }
>
> +static ssize_t fadump_mem_reserved_show(struct kobject *kobj,
> + struct kobj_attribute *attr,
> + char *buf)
> +{
> + return sprintf(buf, "%ld\n", fw_dump.reserve_dump_area_size);
> +}
> +
> static ssize_t fadump_register_show(struct kobject *kobj,
> struct kobj_attribute *attr,
> char *buf)
> @@ -1430,6 +1437,10 @@ static struct kobj_attribute enable_attr =
> __ATTR(enabled,
> static struct kobj_attribute register_attr = __ATTR(registered,
> 0644, fadump_register_show,
> fadump_register_store);
> +static struct kobj_attribute mem_reserved_attr = __ATTR(mem_reserved,
> + 0444, fadump_mem_reserved_show,
> + NULL);
__ATTRI_RO()?
> +
>
> DEFINE_SHOW_ATTRIBUTE(fadump_region);
>
> @@ -1464,6 +1475,10 @@ static void fadump_init_files(void)
> pr_err("unable to create release_mem sysfs file (%d)\n",
> rc);
> }
> + rc = sysfs_create_file(fadump_kobj, _reserved_attr.attr);
> + if (rc)
> + pr_err("unable to create mem_reserved sysfs file (%d)\n",
> +rc);
Again, put it in an attribute group, that would have only required one
line, and not this mess of not cleaning up if something went wrong.
thanks,
greg k-h
[PATCH v4 6/6] powerpc/fadump: sysfs for fadump memory reservation
Add a sys interface to allow querying the memory reserved by FADump for
saving the crash dump.
Also added Documentation/ABI for the new sysfs file.
Signed-off-by: Sourabh Jain
---
Documentation/ABI/testing/sysfs-kernel-fadump| 7 +++
Documentation/powerpc/firmware-assisted-dump.rst | 5 +
arch/powerpc/kernel/fadump.c | 15 +++
3 files changed, 27 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump
b/Documentation/ABI/testing/sysfs-kernel-fadump
index 5d988b919e81..8f7a64a81783 100644
--- a/Documentation/ABI/testing/sysfs-kernel-fadump
+++ b/Documentation/ABI/testing/sysfs-kernel-fadump
@@ -31,3 +31,10 @@ Description: write only
the system is booted to capture the vmcore using FADump.
It is used to release the memory reserved by FADump to
save the crash dump.
+
+What: /sys/kernel/fadump/mem_reserved
+Date: Dec 2019
+Contact: linuxppc-dev@lists.ozlabs.org
+Description: read only
+ Provide information about the amount of memory reserved by
+ FADump to save the crash dump in bytes.
diff --git a/Documentation/powerpc/firmware-assisted-dump.rst
b/Documentation/powerpc/firmware-assisted-dump.rst
index 365c10209ef3..04993eaf3113 100644
--- a/Documentation/powerpc/firmware-assisted-dump.rst
+++ b/Documentation/powerpc/firmware-assisted-dump.rst
@@ -268,6 +268,11 @@ Here is the list of files under kernel sysfs:
be handled and vmcore will not be captured. This interface can be
easily integrated with kdump service start/stop.
+ /sys/kernel/fadump/mem_reserved
+
+ This is used to display the memory reserved by FADump for saving the
+ crash dump.
+
/sys/kernel/fadump_release_mem
This file is available only when FADump is active during
second kernel. This is used to release the reserved memory
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 41a3cda81791..b2af51b7c750 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -1357,6 +1357,13 @@ static ssize_t fadump_enabled_show(struct kobject *kobj,
return sprintf(buf, "%d\n", fw_dump.fadump_enabled);
}
+static ssize_t fadump_mem_reserved_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%ld\n", fw_dump.reserve_dump_area_size);
+}
+
static ssize_t fadump_register_show(struct kobject *kobj,
struct kobj_attribute *attr,
char *buf)
@@ -1430,6 +1437,10 @@ static struct kobj_attribute enable_attr =
__ATTR(enabled,
static struct kobj_attribute register_attr = __ATTR(registered,
0644, fadump_register_show,
fadump_register_store);
+static struct kobj_attribute mem_reserved_attr = __ATTR(mem_reserved,
+ 0444, fadump_mem_reserved_show,
+ NULL);
+
DEFINE_SHOW_ATTRIBUTE(fadump_region);
@@ -1464,6 +1475,10 @@ static void fadump_init_files(void)
pr_err("unable to create release_mem sysfs file (%d)\n",
rc);
}
+ rc = sysfs_create_file(fadump_kobj, _reserved_attr.attr);
+ if (rc)
+ pr_err("unable to create mem_reserved sysfs file (%d)\n",
+ rc);
/* The FADump sysfs are moved from kernel_kobj to fadump_kobj need to
* create symlink at old location to maintain backward compatibility.
--
2.17.2
