[PATCH v2 10/16] x86/resctrl: Allocate per-package structures for known events

Tony Luck posted 16 patches 10 months, 3 weeks ago
There is a newer version of this series
[PATCH v2 10/16] x86/resctrl: Allocate per-package structures for known events
Posted by Tony Luck 10 months, 3 weeks ago
Use the per-package counts of known events to allocate arrays to
make a copy of just the known events.

Add hook into resctrl_exit() to cleanup.

Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 arch/x86/kernel/cpu/resctrl/internal.h  |  2 +
 arch/x86/kernel/cpu/resctrl/core.c      |  2 +
 arch/x86/kernel/cpu/resctrl/intel_aet.c | 60 ++++++++++++++++++++++++-
 3 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index ada402c7678b..2503a24e4177 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -170,8 +170,10 @@ int rdt_get_mon_l3_config(struct rdt_resource *r);
 
 #ifdef CONFIG_INTEL_AET_RESCTRL
 int rdt_get_intel_aet_mon_config(void);
+void rdt_intel_aet_exit(void);
 #else
 static inline int rdt_get_intel_aet_mon_config(void) { return 0; }
+static inline void rdt_intel_aet_exit(void) { };
 #endif
 
 bool rdt_cpu_has(int flag);
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 2adf40d8de32..d011c095aafa 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1095,6 +1095,8 @@ static void __exit resctrl_arch_exit(void)
 {
 	cpuhp_remove_state(rdt_online);
 
+	rdt_intel_aet_exit();
+
 	resctrl_exit();
 }
 
diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
index 67862e81b9e0..e2d8eab997fc 100644
--- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
+++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
@@ -188,6 +188,26 @@ static bool count_events(struct pkg_info *pkg, int max_pkgs, struct pmt_feature_
 	return found;
 }
 
+static int setup(struct pkg_info *pkg, int pkgnum, struct pmt_feature_group *p, int slot)
+{
+	struct telem_entry **tentry;
+
+	for (int i = 0; i < p->count; i++) {
+		for (tentry = telem_entry; *tentry; tentry++) {
+			if (!(*tentry)->active)
+				continue;
+			if (pkgnum != p->regions[i].plat_info.package_id)
+				continue;
+			if (p->regions[i].guid != (*tentry)->guid)
+				continue;
+
+			pkg[pkgnum].regions[slot++] =  p->regions[i];
+		}
+	}
+
+	return slot;
+}
+
 DEFINE_FREE(intel_pmt_put_feature_group, struct pmt_feature_group *,	\
 	if (!IS_ERR_OR_NULL(_T))					\
 		intel_pmt_put_feature_group(_T))
@@ -202,6 +222,8 @@ static bool get_events(void)
 	struct pmt_feature_group *p2 __free(intel_pmt_put_feature_group) = NULL;
 	int num_pkgs = topology_max_packages();
 	struct pkg_info *pkg __free(kfree) = NULL;
+	bool found_known_features = false;
+	int i, slot;
 
 	pkg = kmalloc_array(num_pkgs, sizeof(*pkg_info), GFP_KERNEL | __GFP_ZERO);
 	if (!pkg)
@@ -220,13 +242,32 @@ static bool get_events(void)
 		if (!count_events(pkg, num_pkgs, p2))
 			intel_pmt_put_feature_group(no_free_ptr(p2));
 
+	for (i = 0; i < num_pkgs; i++) {
+		if (!pkg[i].count)
+			continue;
+		found_known_features = true;
+		pkg[i].regions = kmalloc_array(pkg[i].count, sizeof(*pkg[i].regions), GFP_KERNEL);
+		if (!pkg[i].regions)
+			goto fail;
+
+		slot = 0;
+		if (!IS_ERR_VALUE(p1))
+			slot = setup(pkg, i, p1, slot);
+		if (!IS_ERR_VALUE(p2))
+			slot = setup(pkg, i, p2, slot);
+	}
+
 	if (!IS_ERR_OR_NULL(p1))
 		feat_energy = no_free_ptr(p1);
 	if (!IS_ERR_OR_NULL(p2))
 		feat_perf = no_free_ptr(p2);
 	pkg_info = no_free_ptr(pkg);
 
-	return true;
+	return found_known_features;
+fail:
+	while (--i > 0)
+		kfree(pkg[i].regions);
+	return false;
 }
 
 /*
@@ -242,6 +283,23 @@ int rdt_get_intel_aet_mon_config(void)
 	return 1;
 }
 
+/* Clean up when resctrl shuts down completely */
+void rdt_intel_aet_exit(void)
+{
+	int num_pkgs = topology_max_packages();
+
+	if (pkg_info) {
+		for (int i = 0; i < num_pkgs; i++)
+			kfree(pkg_info[i].regions);
+		kfree(pkg_info);
+	}
+
+	if (feat_energy)
+		intel_pmt_put_feature_group(feat_energy);
+	if (feat_perf)
+		intel_pmt_put_feature_group(feat_perf);
+}
+
 /*
  * Late (first mount) initialization. Safe to ask OOBMSM which telemetry
  * event groups are supported.
-- 
2.48.1
Re: [PATCH v2 10/16] x86/resctrl: Allocate per-package structures for known events
Posted by Reinette Chatre 10 months, 2 weeks ago
hi Tony,

On 3/21/25 4:16 PM, Tony Luck wrote:
> Use the per-package counts of known events to allocate arrays to
> make a copy of just the known events.
> 
> Add hook into resctrl_exit() to cleanup.

(above is not done in patch)

> 
> Signed-off-by: Tony Luck <tony.luck@intel.com>
> ---
>  arch/x86/kernel/cpu/resctrl/internal.h  |  2 +
>  arch/x86/kernel/cpu/resctrl/core.c      |  2 +
>  arch/x86/kernel/cpu/resctrl/intel_aet.c | 60 ++++++++++++++++++++++++-
>  3 files changed, 63 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> index ada402c7678b..2503a24e4177 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -170,8 +170,10 @@ int rdt_get_mon_l3_config(struct rdt_resource *r);
>  
>  #ifdef CONFIG_INTEL_AET_RESCTRL
>  int rdt_get_intel_aet_mon_config(void);
> +void rdt_intel_aet_exit(void);
>  #else
>  static inline int rdt_get_intel_aet_mon_config(void) { return 0; }
> +static inline void rdt_intel_aet_exit(void) { };
>  #endif
>  
>  bool rdt_cpu_has(int flag);
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index 2adf40d8de32..d011c095aafa 100644
> --- a/arch/x86/kernel/cpu/resctrl/core.c
> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> @@ -1095,6 +1095,8 @@ static void __exit resctrl_arch_exit(void)
>  {
>  	cpuhp_remove_state(rdt_online);
>  
> +	rdt_intel_aet_exit();
> +
>  	resctrl_exit();
>  }
>  
> diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
> index 67862e81b9e0..e2d8eab997fc 100644
> --- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
> +++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
> @@ -188,6 +188,26 @@ static bool count_events(struct pkg_info *pkg, int max_pkgs, struct pmt_feature_
>  	return found;
>  }
>  
> +static int setup(struct pkg_info *pkg, int pkgnum, struct pmt_feature_group *p, int slot)

Could you please add a comment to this function to explain what it does?

> +{
> +	struct telem_entry **tentry;
> +
> +	for (int i = 0; i < p->count; i++) {
> +		for (tentry = telem_entry; *tentry; tentry++) {
> +			if (!(*tentry)->active)
> +				continue;
> +			if (pkgnum != p->regions[i].plat_info.package_id)
> +				continue;
> +			if (p->regions[i].guid != (*tentry)->guid)
> +				continue;
> +
> +			pkg[pkgnum].regions[slot++] =  p->regions[i];
> +		}
> +	}
> +
> +	return slot;
> +}
> +
>  DEFINE_FREE(intel_pmt_put_feature_group, struct pmt_feature_group *,	\
>  	if (!IS_ERR_OR_NULL(_T))					\
>  		intel_pmt_put_feature_group(_T))
> @@ -202,6 +222,8 @@ static bool get_events(void)
>  	struct pmt_feature_group *p2 __free(intel_pmt_put_feature_group) = NULL;
>  	int num_pkgs = topology_max_packages();
>  	struct pkg_info *pkg __free(kfree) = NULL;
> +	bool found_known_features = false;
> +	int i, slot;
>  
>  	pkg = kmalloc_array(num_pkgs, sizeof(*pkg_info), GFP_KERNEL | __GFP_ZERO);
>  	if (!pkg)
> @@ -220,13 +242,32 @@ static bool get_events(void)
>  		if (!count_events(pkg, num_pkgs, p2))
>  			intel_pmt_put_feature_group(no_free_ptr(p2));
>  
> +	for (i = 0; i < num_pkgs; i++) {
> +		if (!pkg[i].count)
> +			continue;
> +		found_known_features = true;
> +		pkg[i].regions = kmalloc_array(pkg[i].count, sizeof(*pkg[i].regions), GFP_KERNEL);
> +		if (!pkg[i].regions)
> +			goto fail;
> +
> +		slot = 0;
> +		if (!IS_ERR_VALUE(p1))
> +			slot = setup(pkg, i, p1, slot);
> +		if (!IS_ERR_VALUE(p2))
> +			slot = setup(pkg, i, p2, slot);
> +	}
> +
>  	if (!IS_ERR_OR_NULL(p1))
>  		feat_energy = no_free_ptr(p1);
>  	if (!IS_ERR_OR_NULL(p2))
>  		feat_perf = no_free_ptr(p2);
>  	pkg_info = no_free_ptr(pkg);
>  
> -	return true;
> +	return found_known_features;
> +fail:

include/linux/cleanup.h has this to say about mixing goto and free helpers:
"convert all resources that need a "goto" cleanup to scope-based cleanup, or convert
none of them"

> +	while (--i > 0)
> +		kfree(pkg[i].regions);
> +	return false;
>  }
>  
>  /*
> @@ -242,6 +283,23 @@ int rdt_get_intel_aet_mon_config(void)
>  	return 1;
>  }
>  
> +/* Clean up when resctrl shuts down completely */
> +void rdt_intel_aet_exit(void)
> +{
> +	int num_pkgs = topology_max_packages();
> +
> +	if (pkg_info) {
> +		for (int i = 0; i < num_pkgs; i++)
> +			kfree(pkg_info[i].regions);
> +		kfree(pkg_info);
> +	}
> +
> +	if (feat_energy)
> +		intel_pmt_put_feature_group(feat_energy);
> +	if (feat_perf)
> +		intel_pmt_put_feature_group(feat_perf);
> +}
> +
>  /*
>   * Late (first mount) initialization. Safe to ask OOBMSM which telemetry
>   * event groups are supported.

Reinette
Re: [PATCH v2 10/16] x86/resctrl: Allocate per-package structures for known events
Posted by Luck, Tony 10 months, 2 weeks ago
On Mon, Mar 31, 2025 at 09:21:49AM -0700, Reinette Chatre wrote:
> hi Tony,
> 
> On 3/21/25 4:16 PM, Tony Luck wrote:
> > Use the per-package counts of known events to allocate arrays to
> > make a copy of just the known events.
> > 
> > Add hook into resctrl_exit() to cleanup.
> 
> (above is not done in patch)

I think I shuffled it to a different patch. I will track it
down and move this comment to the right place.

> > 
> > Signed-off-by: Tony Luck <tony.luck@intel.com>
> > ---
> >  arch/x86/kernel/cpu/resctrl/internal.h  |  2 +
> >  arch/x86/kernel/cpu/resctrl/core.c      |  2 +
> >  arch/x86/kernel/cpu/resctrl/intel_aet.c | 60 ++++++++++++++++++++++++-
> >  3 files changed, 63 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> > index ada402c7678b..2503a24e4177 100644
> > --- a/arch/x86/kernel/cpu/resctrl/internal.h
> > +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> > @@ -170,8 +170,10 @@ int rdt_get_mon_l3_config(struct rdt_resource *r);
> >  
> >  #ifdef CONFIG_INTEL_AET_RESCTRL
> >  int rdt_get_intel_aet_mon_config(void);
> > +void rdt_intel_aet_exit(void);
> >  #else
> >  static inline int rdt_get_intel_aet_mon_config(void) { return 0; }
> > +static inline void rdt_intel_aet_exit(void) { };
> >  #endif
> >  
> >  bool rdt_cpu_has(int flag);
> > diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> > index 2adf40d8de32..d011c095aafa 100644
> > --- a/arch/x86/kernel/cpu/resctrl/core.c
> > +++ b/arch/x86/kernel/cpu/resctrl/core.c
> > @@ -1095,6 +1095,8 @@ static void __exit resctrl_arch_exit(void)
> >  {
> >  	cpuhp_remove_state(rdt_online);
> >  
> > +	rdt_intel_aet_exit();
> > +
> >  	resctrl_exit();
> >  }
> >  
> > diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
> > index 67862e81b9e0..e2d8eab997fc 100644
> > --- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
> > +++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
> > @@ -188,6 +188,26 @@ static bool count_events(struct pkg_info *pkg, int max_pkgs, struct pmt_feature_
> >  	return found;
> >  }
> >  
> > +static int setup(struct pkg_info *pkg, int pkgnum, struct pmt_feature_group *p, int slot)
> 
> Could you please add a comment to this function to explain what it does?

Indeed yes, it really needs some description.
> 
> > +{
> > +	struct telem_entry **tentry;
> > +
> > +	for (int i = 0; i < p->count; i++) {
> > +		for (tentry = telem_entry; *tentry; tentry++) {
> > +			if (!(*tentry)->active)
> > +				continue;
> > +			if (pkgnum != p->regions[i].plat_info.package_id)
> > +				continue;
> > +			if (p->regions[i].guid != (*tentry)->guid)
> > +				continue;
> > +
> > +			pkg[pkgnum].regions[slot++] =  p->regions[i];
> > +		}
> > +	}
> > +
> > +	return slot;
> > +}
> > +
> >  DEFINE_FREE(intel_pmt_put_feature_group, struct pmt_feature_group *,	\
> >  	if (!IS_ERR_OR_NULL(_T))					\
> >  		intel_pmt_put_feature_group(_T))
> > @@ -202,6 +222,8 @@ static bool get_events(void)
> >  	struct pmt_feature_group *p2 __free(intel_pmt_put_feature_group) = NULL;
> >  	int num_pkgs = topology_max_packages();
> >  	struct pkg_info *pkg __free(kfree) = NULL;
> > +	bool found_known_features = false;
> > +	int i, slot;
> >  
> >  	pkg = kmalloc_array(num_pkgs, sizeof(*pkg_info), GFP_KERNEL | __GFP_ZERO);
> >  	if (!pkg)
> > @@ -220,13 +242,32 @@ static bool get_events(void)
> >  		if (!count_events(pkg, num_pkgs, p2))
> >  			intel_pmt_put_feature_group(no_free_ptr(p2));
> >  
> > +	for (i = 0; i < num_pkgs; i++) {
> > +		if (!pkg[i].count)
> > +			continue;
> > +		found_known_features = true;
> > +		pkg[i].regions = kmalloc_array(pkg[i].count, sizeof(*pkg[i].regions), GFP_KERNEL);
> > +		if (!pkg[i].regions)
> > +			goto fail;
> > +
> > +		slot = 0;
> > +		if (!IS_ERR_VALUE(p1))
> > +			slot = setup(pkg, i, p1, slot);
> > +		if (!IS_ERR_VALUE(p2))
> > +			slot = setup(pkg, i, p2, slot);
> > +	}
> > +
> >  	if (!IS_ERR_OR_NULL(p1))
> >  		feat_energy = no_free_ptr(p1);
> >  	if (!IS_ERR_OR_NULL(p2))
> >  		feat_perf = no_free_ptr(p2);
> >  	pkg_info = no_free_ptr(pkg);
> >  
> > -	return true;
> > +	return found_known_features;
> > +fail:
> 
> include/linux/cleanup.h has this to say about mixing goto and free helpers:
> "convert all resources that need a "goto" cleanup to scope-based cleanup, or convert
> none of them"

Seems an awkward restriction for this case. "pkg" is a pointer to
a dynamic array, and each of the elements of the array might have
been initialized by another allocation. "pkg" is under control of
the __free() cleanup function.

Maybe I could define a custom cleanup (syntax of multi-statement
action to be figured out):

DEFINE_FREE(pkg_free, struct pkg_info *,
	if (_T)
		for (int i = 0; i < num_pkgs; i++)
			kfree(_T[i].regions);
	kfree(_T)
)

	struct pkg_info *pkg __free(pkg_free) = NULL;

> 
> > +	while (--i > 0)
> > +		kfree(pkg[i].regions);
> > +	return false;
> >  }
> >  
> >  /*
> > @@ -242,6 +283,23 @@ int rdt_get_intel_aet_mon_config(void)
> >  	return 1;
> >  }
> >  
> > +/* Clean up when resctrl shuts down completely */
> > +void rdt_intel_aet_exit(void)
> > +{
> > +	int num_pkgs = topology_max_packages();
> > +
> > +	if (pkg_info) {
> > +		for (int i = 0; i < num_pkgs; i++)
> > +			kfree(pkg_info[i].regions);
> > +		kfree(pkg_info);
> > +	}
> > +
> > +	if (feat_energy)
> > +		intel_pmt_put_feature_group(feat_energy);
> > +	if (feat_perf)
> > +		intel_pmt_put_feature_group(feat_perf);
> > +}
> > +
> >  /*
> >   * Late (first mount) initialization. Safe to ask OOBMSM which telemetry
> >   * event groups are supported.
> 
> Reinette
Re: [PATCH v2 10/16] x86/resctrl: Allocate per-package structures for known events
Posted by Luck, Tony 10 months, 2 weeks ago
On Mon, Mar 31, 2025 at 03:23:53PM -0700, Luck, Tony wrote:
> On Mon, Mar 31, 2025 at 09:21:49AM -0700, Reinette Chatre wrote:
> > include/linux/cleanup.h has this to say about mixing goto and free helpers:
> > "convert all resources that need a "goto" cleanup to scope-based cleanup, or convert
> > none of them"
> 
> Seems an awkward restriction for this case. "pkg" is a pointer to
> a dynamic array, and each of the elements of the array might have
> been initialized by another allocation. "pkg" is under control of
> the __free() cleanup function.
> 
> Maybe I could define a custom cleanup (syntax of multi-statement
> action to be figured out):
> 
> DEFINE_FREE(pkg_free, struct pkg_info *,
> 	if (_T)
> 		for (int i = 0; i < num_pkgs; i++)
> 			kfree(_T[i].regions);
> 	kfree(_T)
> )
> 
> 	struct pkg_info *pkg __free(pkg_free) = NULL;

Tried this out and it works (without any odd syntax for the multi-line
action (though I did miss that num_pkgs was a local variable, thankfully
simply initialized from topology_max_packages().


DEFINE_FREE(free_pkg_info, struct pkg_info *,				\
	if (_T)								\
		for (int i = 0; i < topology_max_packages(); i++)	\
			kfree(_T[i].regions);				\
	kfree(_T))

...

	struct pkg_info *pkg __free(free_pkg_info) = NULL;


-Tony