diff mbox series

[v10,05/10] x86/resctrl: Unwind the errors inside rdt_enable_ctx()

Message ID 20230915224227.1336967-6-babu.moger@amd.com
State New
Headers
Series x86/resctrl: Miscellaneous resctrl features |

Commit Message

Moger, Babu Sept. 15, 2023, 10:42 p.m. UTC 
  rdt_enable_ctx() enables the features provided during resctrl mount.

Additions to rdt_enable_ctx() are required to also modify error paths
of rdt_enable_ctx() callers to ensure correct unwinding if errors
are encountered after calling rdt_enable_ctx(). This is error prone.

Introduce rdt_disable_ctx() to refactor the error unwinding of
rdt_enable_ctx() to simplify future additions. This also simplifies
cleanup in rdt_kill_sb().

Remove cdp_disable_all() as it is not used anymore after the refactor.

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 53 ++++++++++++++++----------
 1 file changed, 32 insertions(+), 21 deletions(-)

Comments

Ilpo Järvinen Sept. 29, 2023, 3:22 p.m. UTC | #1 
On Fri, 15 Sep 2023, Babu Moger wrote:

> rdt_enable_ctx() enables the features provided during resctrl mount.
> 
> Additions to rdt_enable_ctx() are required to also modify error paths
> of rdt_enable_ctx() callers to ensure correct unwinding if errors
> are encountered after calling rdt_enable_ctx(). This is error prone.
> 
> Introduce rdt_disable_ctx() to refactor the error unwinding of
> rdt_enable_ctx() to simplify future additions. This also simplifies
> cleanup in rdt_kill_sb().
> 
> Remove cdp_disable_all() as it is not used anymore after the refactor.
> 
> Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> ---
>  arch/x86/kernel/cpu/resctrl/rdtgroup.c | 53 ++++++++++++++++----------
>  1 file changed, 32 insertions(+), 21 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 35945b4bf196..3ea874c80c22 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -2290,14 +2290,6 @@ int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable)
>  	return 0;
>  }
>  
> -static void cdp_disable_all(void)
> -{
> -	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3))
> -		resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
> -	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2))
> -		resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
> -}
> -
>  /*
>   * We don't allow rdtgroup directories to be created anywhere
>   * except the root directory. Thus when looking for the rdtgroup
> @@ -2377,19 +2369,42 @@ static int mkdir_mondata_all(struct kernfs_node *parent_kn,
>  			     struct rdtgroup *prgrp,
>  			     struct kernfs_node **mon_data_kn);
>  
> +static void rdt_disable_ctx(void)
> +{
> +	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
> +	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
> +	set_mba_sc(false);
> +}
> +
>  static int rdt_enable_ctx(struct rdt_fs_context *ctx)
>  {
>  	int ret = 0;
>  
> -	if (ctx->enable_cdpl2)
> +	if (ctx->enable_cdpl2) {
>  		ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, true);
> +		if (ret)
> +			goto out_done;
> +	}
>  
> -	if (!ret && ctx->enable_cdpl3)
> +	if (ctx->enable_cdpl3) {
>  		ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, true);
> +		if (ret)
> +			goto out_cdpl2;
> +	}
>  
> -	if (!ret && ctx->enable_mba_mbps)
> +	if (ctx->enable_mba_mbps) {
>  		ret = set_mba_sc(true);
> +		if (ret)
> +			goto out_cdpl3;
> +	}
> +
> +	return 0;
>  
> +out_cdpl3:
> +	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
> +out_cdpl2:
> +	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
> +out_done:
>  	return ret;
>  }
>  
> @@ -2497,13 +2512,13 @@ static int rdt_get_tree(struct fs_context *fc)
>  	}
>  
>  	ret = rdt_enable_ctx(ctx);
> -	if (ret < 0)
> -		goto out_cdp;
> +	if (ret)
> +		goto out;
>  
>  	ret = schemata_list_create();
>  	if (ret) {
>  		schemata_list_destroy();
> -		goto out_mba;
> +		goto out_ctx;
>  	}
>  
>  	closid_init();
> @@ -2562,11 +2577,8 @@ static int rdt_get_tree(struct fs_context *fc)
>  	kernfs_remove(kn_info);
>  out_schemata_free:
>  	schemata_list_destroy();
> -out_mba:
> -	if (ctx->enable_mba_mbps)
> -		set_mba_sc(false);
> -out_cdp:
> -	cdp_disable_all();
> +out_ctx:
> +	rdt_disable_ctx();
>  out:
>  	rdt_last_cmd_clear();
>  	mutex_unlock(&rdtgroup_mutex);
> @@ -2798,12 +2810,11 @@ static void rdt_kill_sb(struct super_block *sb)
>  	cpus_read_lock();
>  	mutex_lock(&rdtgroup_mutex);
>  
> -	set_mba_sc(false);
> +	rdt_disable_ctx();
>  
>  	/*Put everything back to default values. */
>  	for_each_alloc_capable_rdt_resource(r)
>  		reset_all_ctrls(r);
> -	cdp_disable_all();
>  	rmdir_all_sub();
>  	rdt_pseudo_lock_release();
>  	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
> 

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
diff mbox series

Patch

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 35945b4bf196..3ea874c80c22 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2290,14 +2290,6 @@  int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable)
 	return 0;
 }
 
-static void cdp_disable_all(void)
-{
-	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3))
-		resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
-	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2))
-		resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
-}
-
 /*
  * We don't allow rdtgroup directories to be created anywhere
  * except the root directory. Thus when looking for the rdtgroup
@@ -2377,19 +2369,42 @@  static int mkdir_mondata_all(struct kernfs_node *parent_kn,
 			     struct rdtgroup *prgrp,
 			     struct kernfs_node **mon_data_kn);
 
+static void rdt_disable_ctx(void)
+{
+	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
+	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
+	set_mba_sc(false);
+}
+
 static int rdt_enable_ctx(struct rdt_fs_context *ctx)
 {
 	int ret = 0;
 
-	if (ctx->enable_cdpl2)
+	if (ctx->enable_cdpl2) {
 		ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, true);
+		if (ret)
+			goto out_done;
+	}
 
-	if (!ret && ctx->enable_cdpl3)
+	if (ctx->enable_cdpl3) {
 		ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, true);
+		if (ret)
+			goto out_cdpl2;
+	}
 
-	if (!ret && ctx->enable_mba_mbps)
+	if (ctx->enable_mba_mbps) {
 		ret = set_mba_sc(true);
+		if (ret)
+			goto out_cdpl3;
+	}
+
+	return 0;
 
+out_cdpl3:
+	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
+out_cdpl2:
+	resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
+out_done:
 	return ret;
 }
 
@@ -2497,13 +2512,13 @@  static int rdt_get_tree(struct fs_context *fc)
 	}
 
 	ret = rdt_enable_ctx(ctx);
-	if (ret < 0)
-		goto out_cdp;
+	if (ret)
+		goto out;
 
 	ret = schemata_list_create();
 	if (ret) {
 		schemata_list_destroy();
-		goto out_mba;
+		goto out_ctx;
 	}
 
 	closid_init();
@@ -2562,11 +2577,8 @@  static int rdt_get_tree(struct fs_context *fc)
 	kernfs_remove(kn_info);
 out_schemata_free:
 	schemata_list_destroy();
-out_mba:
-	if (ctx->enable_mba_mbps)
-		set_mba_sc(false);
-out_cdp:
-	cdp_disable_all();
+out_ctx:
+	rdt_disable_ctx();
 out:
 	rdt_last_cmd_clear();
 	mutex_unlock(&rdtgroup_mutex);
@@ -2798,12 +2810,11 @@  static void rdt_kill_sb(struct super_block *sb)
 	cpus_read_lock();
 	mutex_lock(&rdtgroup_mutex);
 
-	set_mba_sc(false);
+	rdt_disable_ctx();
 
 	/*Put everything back to default values. */
 	for_each_alloc_capable_rdt_resource(r)
 		reset_all_ctrls(r);
-	cdp_disable_all();
 	rmdir_all_sub();
 	rdt_pseudo_lock_release();
 	rdtgroup_default.mode = RDT_MODE_SHAREABLE;