diff mbox series

[v4,7/7] x86/resctrl: Add debug files when mounted with debug option

Message ID 168177451010.1758847.568218491528297451.stgit@bmoger-ubuntu
State New
Headers
Series x86/resctrl: Miscellaneous resctrl features |

Commit Message

Moger, Babu April 17, 2023, 11:35 p.m. UTC 
  Add the debug files to the resctrl hierarchy.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
 arch/x86/kernel/cpu/resctrl/internal.h |    1 +
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54 +++++++++++++++++++++++++++++++-
 2 files changed, 54 insertions(+), 1 deletion(-)

Comments

Ilpo Järvinen April 19, 2023, 1:20 p.m. UTC | #1 
On Mon, 17 Apr 2023, Babu Moger wrote:

> Add the debug files to the resctrl hierarchy.
> 
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> ---
>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54 +++++++++++++++++++++++++++++++-
>  2 files changed, 54 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> index 1eac07ebc31b..855109abb480 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -288,6 +288,7 @@ struct rdtgroup {
>  #define RFTYPE_TOP			BIT(4)
>  #define RFTYPE_RES_CACHE		BIT(5)
>  #define RFTYPE_RES_MB			BIT(6)
> +#define RFTYPE_DEBUG			BIT(7)
>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
>  #define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 15ded0dd5b09..1ec4359348c2 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
>  		.mode		= 0444,
>  		.kf_ops		= &rdtgroup_kf_single_ops,
>  		.seq_show	= rdtgroup_rmid_show,
> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
>  	},
>  	{
>  		.name		= "schemata",
> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
>  		.mode		= 0444,
>  		.kf_ops		= &rdtgroup_kf_single_ops,
>  		.seq_show	= rdtgroup_closid_show,
> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
>  	},
>  
>  };
> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
>  			     struct rdtgroup *prgrp,
>  			     struct kernfs_node **mon_data_kn);
>  
> +static void resctrl_add_debug_files(void)
> +{
> +	struct rftype *rfts, *rft;
> +	int len;
> +
> +	rfts = res_common_files;
> +	len = ARRAY_SIZE(res_common_files);
> +
> +	lockdep_assert_held(&rdtgroup_mutex);
> +
> +	for (rft = rfts; rft < rfts + len; rft++) {
> +		if (rft->fflags & RFTYPE_DEBUG) {
> +			rft->fflags &= ~RFTYPE_DEBUG;

I don't fully follow why you need to play with ->fflags like this.

Is it for the ->fflags test in rdtgroup_add_files()? Can't you just do 
some extra masking there for RFTYPE_DEBUG based on resctrl_debug which 
you already keep?

> +			rdtgroup_add_file(rdtgroup_default.kn, rft);
> +		}
> +	}
> +
> +	kernfs_activate(rdtgroup_default.kn);
> +}
> +
> +static void resctrl_remove_debug_files(void)
> +{
> +	struct rftype *rfts, *rft;
> +	int len;
> +
> +	rfts = res_common_files;
> +	len = ARRAY_SIZE(res_common_files);
> +
> +	lockdep_assert_held(&rdtgroup_mutex);
> +
> +	for (rft = rfts; rft < rfts + len; rft++) {
> +		if (!strcmp(rft->name, "mon_hw_id")) {
> +			rft->fflags |= RFTYPE_DEBUG;
> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
> +		} else if (!strcmp(rft->name, "ctrl_hw_id")) {
> +			rft->fflags |= RFTYPE_DEBUG;
> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
> +		}
> +	}
> +
> +	kernfs_activate(rdtgroup_default.kn);
> +}
> +
>  static int rdt_enable_ctx(struct rdt_fs_context *ctx)
>  {
>  	int ret = 0;
> @@ -2433,8 +2478,10 @@ 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)
> +	if (!ret && ctx->enable_debug) {
>  		resctrl_debug = true;
> +		resctrl_add_debug_files();
> +	}
>  
>  	return ret;
>  }
> @@ -2851,6 +2898,11 @@ static void rdt_kill_sb(struct super_block *sb)
>  
>  	set_mba_sc(false);
>  
> +	if (resctrl_debug) {
> +		resctrl_remove_debug_files();
> +		resctrl_debug = false;

Logically, this false assignment belongs to the earlier patch.
Moger, Babu April 19, 2023, 3:16 p.m. UTC | #2 
On 4/19/23 08:20, Ilpo Järvinen wrote:
> On Mon, 17 Apr 2023, Babu Moger wrote:
> 
>> Add the debug files to the resctrl hierarchy.
>>
>> Signed-off-by: Babu Moger <babu.moger@amd.com>
>> ---
>>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
>>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54 +++++++++++++++++++++++++++++++-
>>  2 files changed, 54 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
>> index 1eac07ebc31b..855109abb480 100644
>> --- a/arch/x86/kernel/cpu/resctrl/internal.h
>> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
>> @@ -288,6 +288,7 @@ struct rdtgroup {
>>  #define RFTYPE_TOP			BIT(4)
>>  #define RFTYPE_RES_CACHE		BIT(5)
>>  #define RFTYPE_RES_MB			BIT(6)
>> +#define RFTYPE_DEBUG			BIT(7)
>>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
>>  #define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
>>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index 15ded0dd5b09..1ec4359348c2 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
>>  		.mode		= 0444,
>>  		.kf_ops		= &rdtgroup_kf_single_ops,
>>  		.seq_show	= rdtgroup_rmid_show,
>> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
>>  	},
>>  	{
>>  		.name		= "schemata",
>> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
>>  		.mode		= 0444,
>>  		.kf_ops		= &rdtgroup_kf_single_ops,
>>  		.seq_show	= rdtgroup_closid_show,
>> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
>>  	},
>>  
>>  };
>> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
>>  			     struct rdtgroup *prgrp,
>>  			     struct kernfs_node **mon_data_kn);
>>  
>> +static void resctrl_add_debug_files(void)
>> +{
>> +	struct rftype *rfts, *rft;
>> +	int len;
>> +
>> +	rfts = res_common_files;
>> +	len = ARRAY_SIZE(res_common_files);
>> +
>> +	lockdep_assert_held(&rdtgroup_mutex);
>> +
>> +	for (rft = rfts; rft < rfts + len; rft++) {
>> +		if (rft->fflags & RFTYPE_DEBUG) {
>> +			rft->fflags &= ~RFTYPE_DEBUG;
> 
> I don't fully follow why you need to play with ->fflags like this.

Yes. It is because of this check.
    if (rft->fflags && ((fflags & rft->fflags) == rft->fflags)) {

I am not sure about "== rft->fflags" check. If I remove this check then I
may not have to do all this trick. I can try that.


> Is it for the ->fflags test in rdtgroup_add_files()? Can't you just do 
> some extra masking there for RFTYPE_DEBUG based on resctrl_debug which 
> you already keep?

Yes. Let me experiment little bit.
Thanks
Babu
> 
>> +			rdtgroup_add_file(rdtgroup_default.kn, rft);
>> +		}
>> +	}
>> +
>> +	kernfs_activate(rdtgroup_default.kn);
>> +}
>> +
>> +static void resctrl_remove_debug_files(void)
>> +{
>> +	struct rftype *rfts, *rft;
>> +	int len;
>> +
>> +	rfts = res_common_files;
>> +	len = ARRAY_SIZE(res_common_files);
>> +
>> +	lockdep_assert_held(&rdtgroup_mutex);
>> +
>> +	for (rft = rfts; rft < rfts + len; rft++) {
>> +		if (!strcmp(rft->name, "mon_hw_id")) {
>> +			rft->fflags |= RFTYPE_DEBUG;
>> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
>> +		} else if (!strcmp(rft->name, "ctrl_hw_id")) {
>> +			rft->fflags |= RFTYPE_DEBUG;
>> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
>> +		}
>> +	}
>> +
>> +	kernfs_activate(rdtgroup_default.kn);
>> +}
>> +
>>  static int rdt_enable_ctx(struct rdt_fs_context *ctx)
>>  {
>>  	int ret = 0;
>> @@ -2433,8 +2478,10 @@ 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)
>> +	if (!ret && ctx->enable_debug) {
>>  		resctrl_debug = true;
>> +		resctrl_add_debug_files();
>> +	}
>>  
>>  	return ret;
>>  }
>> @@ -2851,6 +2898,11 @@ static void rdt_kill_sb(struct super_block *sb)
>>  
>>  	set_mba_sc(false);
>>  
>> +	if (resctrl_debug) {
>> +		resctrl_remove_debug_files();
>> +		resctrl_debug = false;
> 
> Logically, this false assignment belongs to the earlier patch.
>
Moger, Babu April 19, 2023, 3:16 p.m. UTC | #3 
On 4/19/23 08:20, Ilpo Järvinen wrote:
> On Mon, 17 Apr 2023, Babu Moger wrote:
> 
>> Add the debug files to the resctrl hierarchy.
>>
>> Signed-off-by: Babu Moger <babu.moger@amd.com>
>> ---
>>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
>>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54 +++++++++++++++++++++++++++++++-
>>  2 files changed, 54 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
>> index 1eac07ebc31b..855109abb480 100644
>> --- a/arch/x86/kernel/cpu/resctrl/internal.h
>> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
>> @@ -288,6 +288,7 @@ struct rdtgroup {
>>  #define RFTYPE_TOP			BIT(4)
>>  #define RFTYPE_RES_CACHE		BIT(5)
>>  #define RFTYPE_RES_MB			BIT(6)
>> +#define RFTYPE_DEBUG			BIT(7)
>>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
>>  #define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
>>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index 15ded0dd5b09..1ec4359348c2 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
>>  		.mode		= 0444,
>>  		.kf_ops		= &rdtgroup_kf_single_ops,
>>  		.seq_show	= rdtgroup_rmid_show,
>> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
>>  	},
>>  	{
>>  		.name		= "schemata",
>> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
>>  		.mode		= 0444,
>>  		.kf_ops		= &rdtgroup_kf_single_ops,
>>  		.seq_show	= rdtgroup_closid_show,
>> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
>>  	},
>>  
>>  };
>> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
>>  			     struct rdtgroup *prgrp,
>>  			     struct kernfs_node **mon_data_kn);
>>  
>> +static void resctrl_add_debug_files(void)
>> +{
>> +	struct rftype *rfts, *rft;
>> +	int len;
>> +
>> +	rfts = res_common_files;
>> +	len = ARRAY_SIZE(res_common_files);
>> +
>> +	lockdep_assert_held(&rdtgroup_mutex);
>> +
>> +	for (rft = rfts; rft < rfts + len; rft++) {
>> +		if (rft->fflags & RFTYPE_DEBUG) {
>> +			rft->fflags &= ~RFTYPE_DEBUG;
> 
> I don't fully follow why you need to play with ->fflags like this.
> 
> Is it for the ->fflags test in rdtgroup_add_files()? Can't you just do 
> some extra masking there for RFTYPE_DEBUG based on resctrl_debug which 
> you already keep?
> 
>> +			rdtgroup_add_file(rdtgroup_default.kn, rft);
>> +		}
>> +	}
>> +
>> +	kernfs_activate(rdtgroup_default.kn);
>> +}
>> +
>> +static void resctrl_remove_debug_files(void)
>> +{
>> +	struct rftype *rfts, *rft;
>> +	int len;
>> +
>> +	rfts = res_common_files;
>> +	len = ARRAY_SIZE(res_common_files);
>> +
>> +	lockdep_assert_held(&rdtgroup_mutex);
>> +
>> +	for (rft = rfts; rft < rfts + len; rft++) {
>> +		if (!strcmp(rft->name, "mon_hw_id")) {
>> +			rft->fflags |= RFTYPE_DEBUG;
>> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
>> +		} else if (!strcmp(rft->name, "ctrl_hw_id")) {
>> +			rft->fflags |= RFTYPE_DEBUG;
>> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
>> +		}
>> +	}
>> +
>> +	kernfs_activate(rdtgroup_default.kn);
>> +}
>> +
>>  static int rdt_enable_ctx(struct rdt_fs_context *ctx)
>>  {
>>  	int ret = 0;
>> @@ -2433,8 +2478,10 @@ 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)
>> +	if (!ret && ctx->enable_debug) {
>>  		resctrl_debug = true;
>> +		resctrl_add_debug_files();
>> +	}
>>  
>>  	return ret;
>>  }
>> @@ -2851,6 +2898,11 @@ static void rdt_kill_sb(struct super_block *sb)
>>  
>>  	set_mba_sc(false);
>>  
>> +	if (resctrl_debug) {
>> +		resctrl_remove_debug_files();
>> +		resctrl_debug = false;
> 
> Logically, this false assignment belongs to the earlier patch.

Ok. Sure
Moger, Babu April 19, 2023, 5:16 p.m. UTC | #4 
On 4/19/23 08:20, Ilpo Järvinen wrote:
> On Mon, 17 Apr 2023, Babu Moger wrote:
> 
>> Add the debug files to the resctrl hierarchy.
>>
>> Signed-off-by: Babu Moger <babu.moger@amd.com>
>> ---
>>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
>>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54 +++++++++++++++++++++++++++++++-
>>  2 files changed, 54 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
>> index 1eac07ebc31b..855109abb480 100644
>> --- a/arch/x86/kernel/cpu/resctrl/internal.h
>> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
>> @@ -288,6 +288,7 @@ struct rdtgroup {
>>  #define RFTYPE_TOP			BIT(4)
>>  #define RFTYPE_RES_CACHE		BIT(5)
>>  #define RFTYPE_RES_MB			BIT(6)
>> +#define RFTYPE_DEBUG			BIT(7)
>>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
>>  #define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
>>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index 15ded0dd5b09..1ec4359348c2 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
>>  		.mode		= 0444,
>>  		.kf_ops		= &rdtgroup_kf_single_ops,
>>  		.seq_show	= rdtgroup_rmid_show,
>> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
>>  	},
>>  	{
>>  		.name		= "schemata",
>> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
>>  		.mode		= 0444,
>>  		.kf_ops		= &rdtgroup_kf_single_ops,
>>  		.seq_show	= rdtgroup_closid_show,
>> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
>>  	},
>>  
>>  };
>> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
>>  			     struct rdtgroup *prgrp,
>>  			     struct kernfs_node **mon_data_kn);
>>  
>> +static void resctrl_add_debug_files(void)
>> +{
>> +	struct rftype *rfts, *rft;
>> +	int len;
>> +
>> +	rfts = res_common_files;
>> +	len = ARRAY_SIZE(res_common_files);
>> +
>> +	lockdep_assert_held(&rdtgroup_mutex);
>> +
>> +	for (rft = rfts; rft < rfts + len; rft++) {
>> +		if (rft->fflags & RFTYPE_DEBUG) {
>> +			rft->fflags &= ~RFTYPE_DEBUG;
> 
> I don't fully follow why you need to play with ->fflags like this.
> 
> Is it for the ->fflags test in rdtgroup_add_files()? Can't you just do 
> some extra masking there for RFTYPE_DEBUG based on resctrl_debug which 
> you already keep?

Actually with this change, I can remove all these tricks here.
I don't have to change the check "if (rft->fflags && ((fflags &
rft->fflags) == rft->fflags)) {"

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 1ec4359348c2..b560c44817bb 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1925,6 +1925,9 @@ static int rdtgroup_add_files(struct kernfs_node
*kn, unsigned long fflags)

        lockdep_assert_held(&rdtgroup_mutex);

+       if (resctrl_debug)
+               fflags |= RFTYPE_DEBUG;
+
        for (rft = rfts; rft < rfts + len; rft++) {
                if (rft->fflags && ((fflags & rft->fflags) == rft->fflags)) {
                        ret = rdtgroup_add_file(kn, rft);


> 
>> +			rdtgroup_add_file(rdtgroup_default.kn, rft);
>> +		}
>> +	}
>> +
>> +	kernfs_activate(rdtgroup_default.kn);
>> +}
>> +
>> +static void resctrl_remove_debug_files(void)
>> +{
>> +	struct rftype *rfts, *rft;
>> +	int len;
>> +
>> +	rfts = res_common_files;
>> +	len = ARRAY_SIZE(res_common_files);
>> +
>> +	lockdep_assert_held(&rdtgroup_mutex);
>> +
>> +	for (rft = rfts; rft < rfts + len; rft++) {
>> +		if (!strcmp(rft->name, "mon_hw_id")) {
>> +			rft->fflags |= RFTYPE_DEBUG;
>> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
>> +		} else if (!strcmp(rft->name, "ctrl_hw_id")) {
>> +			rft->fflags |= RFTYPE_DEBUG;
>> +			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
>> +		}
>> +	}
>> +
>> +	kernfs_activate(rdtgroup_default.kn);
>> +}
>> +
>>  static int rdt_enable_ctx(struct rdt_fs_context *ctx)
>>  {
>>  	int ret = 0;
>> @@ -2433,8 +2478,10 @@ 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)
>> +	if (!ret && ctx->enable_debug) {
>>  		resctrl_debug = true;
>> +		resctrl_add_debug_files();
>> +	}
>>  
>>  	return ret;
>>  }
>> @@ -2851,6 +2898,11 @@ static void rdt_kill_sb(struct super_block *sb)
>>  
>>  	set_mba_sc(false);
>>  
>> +	if (resctrl_debug) {
>> +		resctrl_remove_debug_files();
>> +		resctrl_debug = false;
> 
> Logically, this false assignment belongs to the earlier patch.
>
Ilpo Järvinen April 20, 2023, 8:59 a.m. UTC | #5 
On Wed, 19 Apr 2023, Moger, Babu wrote:

> 
> 
> On 4/19/23 08:20, Ilpo Järvinen wrote:
> > On Mon, 17 Apr 2023, Babu Moger wrote:
> > 
> >> Add the debug files to the resctrl hierarchy.
> >>
> >> Signed-off-by: Babu Moger <babu.moger@amd.com>
> >> ---
> >>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
> >>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54 +++++++++++++++++++++++++++++++-
> >>  2 files changed, 54 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> >> index 1eac07ebc31b..855109abb480 100644
> >> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> >> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> >> @@ -288,6 +288,7 @@ struct rdtgroup {
> >>  #define RFTYPE_TOP			BIT(4)
> >>  #define RFTYPE_RES_CACHE		BIT(5)
> >>  #define RFTYPE_RES_MB			BIT(6)
> >> +#define RFTYPE_DEBUG			BIT(7)
> >>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
> >>  #define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
> >>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
> >> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> >> index 15ded0dd5b09..1ec4359348c2 100644
> >> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> >> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> >> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
> >>  		.mode		= 0444,
> >>  		.kf_ops		= &rdtgroup_kf_single_ops,
> >>  		.seq_show	= rdtgroup_rmid_show,
> >> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
> >>  	},
> >>  	{
> >>  		.name		= "schemata",
> >> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
> >>  		.mode		= 0444,
> >>  		.kf_ops		= &rdtgroup_kf_single_ops,
> >>  		.seq_show	= rdtgroup_closid_show,
> >> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
> >>  	},
> >>  
> >>  };
> >> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
> >>  			     struct rdtgroup *prgrp,
> >>  			     struct kernfs_node **mon_data_kn);
> >>  
> >> +static void resctrl_add_debug_files(void)
> >> +{
> >> +	struct rftype *rfts, *rft;
> >> +	int len;
> >> +
> >> +	rfts = res_common_files;
> >> +	len = ARRAY_SIZE(res_common_files);
> >> +
> >> +	lockdep_assert_held(&rdtgroup_mutex);
> >> +
> >> +	for (rft = rfts; rft < rfts + len; rft++) {
> >> +		if (rft->fflags & RFTYPE_DEBUG) {
> >> +			rft->fflags &= ~RFTYPE_DEBUG;
> > 
> > I don't fully follow why you need to play with ->fflags like this.
> > 
> > Is it for the ->fflags test in rdtgroup_add_files()? Can't you just do 
> > some extra masking there for RFTYPE_DEBUG based on resctrl_debug which 
> > you already keep?
> 
> Actually with this change, I can remove all these tricks here.
> I don't have to change the check "if (rft->fflags && ((fflags &
> rft->fflags) == rft->fflags)) {"
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 1ec4359348c2..b560c44817bb 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -1925,6 +1925,9 @@ static int rdtgroup_add_files(struct kernfs_node
> *kn, unsigned long fflags)
> 
>         lockdep_assert_held(&rdtgroup_mutex);
> 
> +       if (resctrl_debug)
> +               fflags |= RFTYPE_DEBUG;

Yes, looks good.

It matches to the idea I had in my mind but doesn't require putting it 
into the if condition itself.

> +
>         for (rft = rfts; rft < rfts + len; rft++) {
>                 if (rft->fflags && ((fflags & rft->fflags) == rft->fflags)) {
>                         ret = rdtgroup_add_file(kn, rft);
> 
> 
> > 
> >> +			rdtgroup_add_file(rdtgroup_default.kn, rft);
> >> +		}
> >> +	}
Moger, Babu April 21, 2023, 6:47 p.m. UTC | #6 
[AMD Official Use Only - General]



> -----Original Message-----
> From: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Sent: Thursday, April 20, 2023 3:59 AM
> To: Moger, Babu <Babu.Moger@amd.com>
> Cc: corbet@lwn.net; Reinette Chatre <reinette.chatre@intel.com>;
> tglx@linutronix.de; mingo@redhat.com; bp@alien8.de; fenghua.yu@intel.com;
> dave.hansen@linux.intel.com; x86@kernel.org; hpa@zytor.com;
> paulmck@kernel.org; akpm@linux-foundation.org; quic_neeraju@quicinc.com;
> rdunlap@infradead.org; damien.lemoal@opensource.wdc.com;
> songmuchun@bytedance.com; peterz@infradead.org; jpoimboe@kernel.org;
> pbonzini@redhat.com; chang.seok.bae@intel.com;
> pawan.kumar.gupta@linux.intel.com; jmattson@google.com;
> daniel.sneddon@linux.intel.com; Das1, Sandipan <Sandipan.Das@amd.com>;
> tony.luck@intel.com; james.morse@arm.com; linux-doc@vger.kernel.org;
> LKML <linux-kernel@vger.kernel.org>; bagasdotme@gmail.com;
> eranian@google.com; christophe.leroy@csgroup.eu; jarkko@kernel.org;
> adrian.hunter@intel.com; quic_jiles@quicinc.com; peternewman@google.com
> Subject: Re: [PATCH v4 7/7] x86/resctrl: Add debug files when mounted with
> debug option
> 
> On Wed, 19 Apr 2023, Moger, Babu wrote:
> 
> >
> >
> > On 4/19/23 08:20, Ilpo Järvinen wrote:
> > > On Mon, 17 Apr 2023, Babu Moger wrote:
> > >
> > >> Add the debug files to the resctrl hierarchy.
> > >>
> > >> Signed-off-by: Babu Moger <babu.moger@amd.com>
> > >> ---
> > >>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
> > >>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54
> +++++++++++++++++++++++++++++++-
> > >>  2 files changed, 54 insertions(+), 1 deletion(-)
> > >>
> > >> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h
> > >> b/arch/x86/kernel/cpu/resctrl/internal.h
> > >> index 1eac07ebc31b..855109abb480 100644
> > >> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> > >> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> > >> @@ -288,6 +288,7 @@ struct rdtgroup {
> > >>  #define RFTYPE_TOP			BIT(4)
> > >>  #define RFTYPE_RES_CACHE		BIT(5)
> > >>  #define RFTYPE_RES_MB			BIT(6)
> > >> +#define RFTYPE_DEBUG			BIT(7)
> > >>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO |
> RFTYPE_CTRL)
> > >>  #define RFTYPE_MON_INFO			(RFTYPE_INFO |
> RFTYPE_MON)
> > >>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO |
> RFTYPE_TOP)
> > >> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > >> b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > >> index 15ded0dd5b09..1ec4359348c2 100644
> > >> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > >> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > >> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
> > >>  		.mode		= 0444,
> > >>  		.kf_ops		= &rdtgroup_kf_single_ops,
> > >>  		.seq_show	= rdtgroup_rmid_show,
> > >> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
> > >>  	},
> > >>  	{
> > >>  		.name		= "schemata",
> > >> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
> > >>  		.mode		= 0444,
> > >>  		.kf_ops		= &rdtgroup_kf_single_ops,
> > >>  		.seq_show	= rdtgroup_closid_show,
> > >> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
> > >>  	},
> > >>
> > >>  };
> > >> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct
> kernfs_node *parent_kn,
> > >>  			     struct rdtgroup *prgrp,
> > >>  			     struct kernfs_node **mon_data_kn);
> > >>
> > >> +static void resctrl_add_debug_files(void) {
> > >> +	struct rftype *rfts, *rft;
> > >> +	int len;
> > >> +
> > >> +	rfts = res_common_files;
> > >> +	len = ARRAY_SIZE(res_common_files);
> > >> +
> > >> +	lockdep_assert_held(&rdtgroup_mutex);
> > >> +
> > >> +	for (rft = rfts; rft < rfts + len; rft++) {
> > >> +		if (rft->fflags & RFTYPE_DEBUG) {
> > >> +			rft->fflags &= ~RFTYPE_DEBUG;
> > >
> > > I don't fully follow why you need to play with ->fflags like this.
> > >
> > > Is it for the ->fflags test in rdtgroup_add_files()? Can't you just
> > > do some extra masking there for RFTYPE_DEBUG based on resctrl_debug
> > > which you already keep?
> >
> > Actually with this change, I can remove all these tricks here.
> > I don't have to change the check "if (rft->fflags && ((fflags &
> > rft->fflags) == rft->fflags)) {"
> >
> > diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > index 1ec4359348c2..b560c44817bb 100644
> > --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > @@ -1925,6 +1925,9 @@ static int rdtgroup_add_files(struct kernfs_node
> > *kn, unsigned long fflags)
> >
> >         lockdep_assert_held(&rdtgroup_mutex);
> >
> > +       if (resctrl_debug)
> > +               fflags |= RFTYPE_DEBUG;
> 
> Yes, looks good.
> 
> It matches to the idea I had in my mind but doesn't require putting it into the if
> condition itself.
Without if condition?  How?  Let me know.
Thanks
Babu
Ilpo Järvinen April 24, 2023, 3:12 p.m. UTC | #7 
On Fri, 21 Apr 2023, Moger, Babu wrote:
> > -----Original Message-----
> > From: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> > Sent: Thursday, April 20, 2023 3:59 AM
> > To: Moger, Babu <Babu.Moger@amd.com>
> > Cc: corbet@lwn.net; Reinette Chatre <reinette.chatre@intel.com>;
> > tglx@linutronix.de; mingo@redhat.com; bp@alien8.de; fenghua.yu@intel.com;
> > dave.hansen@linux.intel.com; x86@kernel.org; hpa@zytor.com;
> > paulmck@kernel.org; akpm@linux-foundation.org; quic_neeraju@quicinc.com;
> > rdunlap@infradead.org; damien.lemoal@opensource.wdc.com;
> > songmuchun@bytedance.com; peterz@infradead.org; jpoimboe@kernel.org;
> > pbonzini@redhat.com; chang.seok.bae@intel.com;
> > pawan.kumar.gupta@linux.intel.com; jmattson@google.com;
> > daniel.sneddon@linux.intel.com; Das1, Sandipan <Sandipan.Das@amd.com>;
> > tony.luck@intel.com; james.morse@arm.com; linux-doc@vger.kernel.org;
> > LKML <linux-kernel@vger.kernel.org>; bagasdotme@gmail.com;
> > eranian@google.com; christophe.leroy@csgroup.eu; jarkko@kernel.org;
> > adrian.hunter@intel.com; quic_jiles@quicinc.com; peternewman@google.com
> > Subject: Re: [PATCH v4 7/7] x86/resctrl: Add debug files when mounted with
> > debug option
> > 
> > On Wed, 19 Apr 2023, Moger, Babu wrote:
> > 
> > >
> > >
> > > On 4/19/23 08:20, Ilpo Järvinen wrote:
> > > > On Mon, 17 Apr 2023, Babu Moger wrote:
> > > >
> > > >> Add the debug files to the resctrl hierarchy.
> > > >>
> > > >> Signed-off-by: Babu Moger <babu.moger@amd.com>
> > > >> ---
> > > >>  arch/x86/kernel/cpu/resctrl/internal.h |    1 +
> > > >>  arch/x86/kernel/cpu/resctrl/rdtgroup.c |   54
> > +++++++++++++++++++++++++++++++-
> > > >>  2 files changed, 54 insertions(+), 1 deletion(-)
> > > >>
> > > >> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h
> > > >> b/arch/x86/kernel/cpu/resctrl/internal.h
> > > >> index 1eac07ebc31b..855109abb480 100644
> > > >> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> > > >> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> > > >> @@ -288,6 +288,7 @@ struct rdtgroup {
> > > >>  #define RFTYPE_TOP			BIT(4)
> > > >>  #define RFTYPE_RES_CACHE		BIT(5)
> > > >>  #define RFTYPE_RES_MB			BIT(6)
> > > >> +#define RFTYPE_DEBUG			BIT(7)
> > > >>  #define RFTYPE_CTRL_INFO		(RFTYPE_INFO |
> > RFTYPE_CTRL)
> > > >>  #define RFTYPE_MON_INFO			(RFTYPE_INFO |
> > RFTYPE_MON)
> > > >>  #define RFTYPE_TOP_INFO			(RFTYPE_INFO |
> > RFTYPE_TOP)
> > > >> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > >> b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > >> index 15ded0dd5b09..1ec4359348c2 100644
> > > >> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > >> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > >> @@ -1880,6 +1880,7 @@ static struct rftype res_common_files[] = {
> > > >>  		.mode		= 0444,
> > > >>  		.kf_ops		= &rdtgroup_kf_single_ops,
> > > >>  		.seq_show	= rdtgroup_rmid_show,
> > > >> +		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
> > > >>  	},
> > > >>  	{
> > > >>  		.name		= "schemata",
> > > >> @@ -1909,6 +1910,7 @@ static struct rftype res_common_files[] = {
> > > >>  		.mode		= 0444,
> > > >>  		.kf_ops		= &rdtgroup_kf_single_ops,
> > > >>  		.seq_show	= rdtgroup_closid_show,
> > > >> +		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
> > > >>  	},
> > > >>
> > > >>  };
> > > >> @@ -2420,6 +2422,49 @@ static int mkdir_mondata_all(struct
> > kernfs_node *parent_kn,
> > > >>  			     struct rdtgroup *prgrp,
> > > >>  			     struct kernfs_node **mon_data_kn);
> > > >>
> > > >> +static void resctrl_add_debug_files(void) {
> > > >> +	struct rftype *rfts, *rft;
> > > >> +	int len;
> > > >> +
> > > >> +	rfts = res_common_files;
> > > >> +	len = ARRAY_SIZE(res_common_files);
> > > >> +
> > > >> +	lockdep_assert_held(&rdtgroup_mutex);
> > > >> +
> > > >> +	for (rft = rfts; rft < rfts + len; rft++) {
> > > >> +		if (rft->fflags & RFTYPE_DEBUG) {
> > > >> +			rft->fflags &= ~RFTYPE_DEBUG;
> > > >
> > > > I don't fully follow why you need to play with ->fflags like this.
> > > >
> > > > Is it for the ->fflags test in rdtgroup_add_files()? Can't you just
> > > > do some extra masking there for RFTYPE_DEBUG based on resctrl_debug
> > > > which you already keep?
> > >
> > > Actually with this change, I can remove all these tricks here.
> > > I don't have to change the check "if (rft->fflags && ((fflags &
> > > rft->fflags) == rft->fflags)) {"
> > >
> > > diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > index 1ec4359348c2..b560c44817bb 100644
> > > --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > > @@ -1925,6 +1925,9 @@ static int rdtgroup_add_files(struct kernfs_node
> > > *kn, unsigned long fflags)
> > >
> > >         lockdep_assert_held(&rdtgroup_mutex);
> > >
> > > +       if (resctrl_debug)
> > > +               fflags |= RFTYPE_DEBUG;
> > 
> > Yes, looks good.
> > 
> > It matches to the idea I had in my mind but doesn't require putting it 
> > into the if condition itself.
>
> Without if condition?  How?  Let me know.

I was referring to the if condition within the loop, not to doing it
without some conditional (I had an (resctrl_debug ? RFTYPE_DEBUG : 0)
construct in my mind).

To remove if, it would, of course, be possible to use another static 
file-level variable but it doesn't seem justified. I think what you 
proposed is fine for this use and looks clean.
diff mbox series

Patch

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 1eac07ebc31b..855109abb480 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -288,6 +288,7 @@  struct rdtgroup {
 #define RFTYPE_TOP			BIT(4)
 #define RFTYPE_RES_CACHE		BIT(5)
 #define RFTYPE_RES_MB			BIT(6)
+#define RFTYPE_DEBUG			BIT(7)
 #define RFTYPE_CTRL_INFO		(RFTYPE_INFO | RFTYPE_CTRL)
 #define RFTYPE_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
 #define RFTYPE_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 15ded0dd5b09..1ec4359348c2 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1880,6 +1880,7 @@  static struct rftype res_common_files[] = {
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdtgroup_rmid_show,
+		.fflags		= RFTYPE_BASE | RFTYPE_DEBUG,
 	},
 	{
 		.name		= "schemata",
@@ -1909,6 +1910,7 @@  static struct rftype res_common_files[] = {
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdtgroup_closid_show,
+		.fflags		= RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
 	},
 
 };
@@ -2420,6 +2422,49 @@  static int mkdir_mondata_all(struct kernfs_node *parent_kn,
 			     struct rdtgroup *prgrp,
 			     struct kernfs_node **mon_data_kn);
 
+static void resctrl_add_debug_files(void)
+{
+	struct rftype *rfts, *rft;
+	int len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if (rft->fflags & RFTYPE_DEBUG) {
+			rft->fflags &= ~RFTYPE_DEBUG;
+			rdtgroup_add_file(rdtgroup_default.kn, rft);
+		}
+	}
+
+	kernfs_activate(rdtgroup_default.kn);
+}
+
+static void resctrl_remove_debug_files(void)
+{
+	struct rftype *rfts, *rft;
+	int len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if (!strcmp(rft->name, "mon_hw_id")) {
+			rft->fflags |= RFTYPE_DEBUG;
+			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
+		} else if (!strcmp(rft->name, "ctrl_hw_id")) {
+			rft->fflags |= RFTYPE_DEBUG;
+			kernfs_remove_by_name(rdtgroup_default.kn, rft->name);
+		}
+	}
+
+	kernfs_activate(rdtgroup_default.kn);
+}
+
 static int rdt_enable_ctx(struct rdt_fs_context *ctx)
 {
 	int ret = 0;
@@ -2433,8 +2478,10 @@  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)
+	if (!ret && ctx->enable_debug) {
 		resctrl_debug = true;
+		resctrl_add_debug_files();
+	}
 
 	return ret;
 }
@@ -2851,6 +2898,11 @@  static void rdt_kill_sb(struct super_block *sb)
 
 	set_mba_sc(false);
 
+	if (resctrl_debug) {
+		resctrl_remove_debug_files();
+		resctrl_debug = false;
+	}
+
 	/*Put everything back to default values. */
 	for_each_alloc_capable_rdt_resource(r)
 		reset_all_ctrls(r);