Hi Reinette,
On 7/7/23 16:42, Reinette Chatre wrote:
> Hi Babu,
>
> On 6/1/2023 12:01 PM, Babu Moger wrote:
>> Add "-o debug" option to mount resctrl filesystem in debug mode.
>> This option can be used for adding extra files to help debug
>> resctrl issues.
>
> Please avoid uncertainty in the changelog (re. "can be used"). I
ok Sure.
> think it will help to be more specific if the first and last
> hunks of patch 8 is merged into this patch, making it clear
> that the debug mount option is in support of debug files with
> this changelog written to support that.
Sure. Will do that.
>
>> For example, hardware uses CLOSID and RMIDs to control and monitor
>> resctrl resources. These numbers are not visible to the user. These
>> details can help to debug issues. Debug option provides a method to
>> add these files to resctrl.
>
> With the debug file support added here this extra motivation should
> not be necessary (remaining hunks of patch 8 can be moved to where
> these files are introduced).
Sure.
>>
>> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
>> ---
>> Documentation/arch/x86/resctrl.rst | 3 +++
>> arch/x86/kernel/cpu/resctrl/internal.h | 1 +
>> arch/x86/kernel/cpu/resctrl/rdtgroup.c | 15 +++++++++++++++
>> 3 files changed, 19 insertions(+)
>>
>> diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst
>> index 290f01aa3002..afdee4d1f691 100644
>> --- a/Documentation/arch/x86/resctrl.rst
>> +++ b/Documentation/arch/x86/resctrl.rst
>> @@ -46,6 +46,9 @@ mount options are:
>> "mba_MBps":
>> Enable the MBA Software Controller(mba_sc) to specify MBA
>> bandwidth in MBps
>> +"debug":
>> + Make debug files accessible. Available debug files are annotated with
>> + "Available only with debug option".
>>
>
> At the risk of becoming unreadable, the earlier documentation of the mount
> command should also change.
Ok. Sure
>
>> L2 and L3 CDP are controlled separately.
>>
>> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
>> index c20cd6acb7a3..c07c6517d856 100644
>> --- a/arch/x86/kernel/cpu/resctrl/internal.h
>> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
>> @@ -59,6 +59,7 @@ struct rdt_fs_context {
>> bool enable_cdpl2;
>> bool enable_cdpl3;
>> bool enable_mba_mbps;
>> + bool enable_debug;
>> };
>>
>> static inline struct rdt_fs_context *rdt_fc2context(struct fs_context *fc)
>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index baed20b2d788..be91dea5f927 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -56,6 +56,8 @@ static char last_cmd_status_buf[512];
>>
>> struct dentry *debugfs_resctrl;
>>
>> +static bool resctrl_debug;
>> +
>> void rdt_last_cmd_clear(void)
>> {
>> lockdep_assert_held(&rdtgroup_mutex);
>> @@ -2368,6 +2370,9 @@ static int rdt_enable_ctx(struct rdt_fs_context *ctx)
>> if (!ret && ctx->enable_mba_mbps)
>> ret = set_mba_sc(true);
>>
>> + if (!ret && ctx->enable_debug)
>> + resctrl_debug = true;
>> +
>> return ret;
>> }
>
> Looks like unwinding of rdt_enable_ctx() errors is done in the caller, this is
> not ideal and additions like above cause some error unwinding to be omitted.
> I cannot see why rdt_enable_ctx() cannot do its own error unwinding. This
> may be better as a separate patch.
>
Sure. Will do error unwinding of rdt_enable_ctx as a separate patch before
this patch. That seems more appropriate.
--
Thanks
Babu Moger
