From cb07d71f01017b7c2885ed629da9b973cb56b1d2 Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Mon, 16 Oct 2023 19:23:05 -0500 Subject: x86/resctrl: Introduce "-o debug" mount option MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add "-o debug" option to mount resctrl filesystem in debug mode. When in debug mode resctrl displays files that have the new RFTYPE_DEBUG flag to help resctrl debugging. Signed-off-by: Babu Moger Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Peter Newman Reviewed-by: Tan Shaopeng Reviewed-by: Fenghua Yu Reviewed-by: Reinette Chatre Reviewed-by: Ilpo Järvinen Tested-by: Peter Newman Tested-by: Tan Shaopeng Link: https://lore.kernel.org/r/20231017002308.134480-7-babu.moger@amd.com --- Documentation/arch/x86/resctrl.rst | 5 ++++- arch/x86/kernel/cpu/resctrl/internal.h | 2 ++ arch/x86/kernel/cpu/resctrl/rdtgroup.c | 18 ++++++++++++++++++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst index 178ab1d8f747..68f11611f341 100644 --- a/Documentation/arch/x86/resctrl.rst +++ b/Documentation/arch/x86/resctrl.rst @@ -35,7 +35,7 @@ about the feature from resctrl's info directory. To use the feature mount the file system:: - # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps]] /sys/fs/resctrl + # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps][,debug]] /sys/fs/resctrl mount options are: @@ -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". 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 ba4611111212..b816b902b5c0 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) @@ -248,6 +249,7 @@ struct rdtgroup { #define RFTYPE_TOP BIT(6) #define RFTYPE_RES_CACHE BIT(8) #define RFTYPE_RES_MB BIT(9) +#define RFTYPE_DEBUG BIT(10) #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 55da93b5ca53..84e0f45578dd 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -59,6 +59,8 @@ static void rdtgroup_destroy_root(void); struct dentry *debugfs_resctrl; +static bool resctrl_debug; + void rdt_last_cmd_clear(void) { lockdep_assert_held(&rdtgroup_mutex); @@ -1892,6 +1894,9 @@ 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); @@ -2395,6 +2400,8 @@ 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); + + resctrl_debug = false; } static int rdt_enable_ctx(struct rdt_fs_context *ctx) @@ -2419,6 +2426,9 @@ static int rdt_enable_ctx(struct rdt_fs_context *ctx) goto out_cdpl3; } + if (ctx->enable_debug) + resctrl_debug = true; + return 0; out_cdpl3: @@ -2623,6 +2633,7 @@ enum rdt_param { Opt_cdp, Opt_cdpl2, Opt_mba_mbps, + Opt_debug, nr__rdt_params }; @@ -2630,6 +2641,7 @@ static const struct fs_parameter_spec rdt_fs_parameters[] = { fsparam_flag("cdp", Opt_cdp), fsparam_flag("cdpl2", Opt_cdpl2), fsparam_flag("mba_MBps", Opt_mba_mbps), + fsparam_flag("debug", Opt_debug), {} }; @@ -2655,6 +2667,9 @@ static int rdt_parse_param(struct fs_context *fc, struct fs_parameter *param) return -EINVAL; ctx->enable_mba_mbps = true; return 0; + case Opt_debug: + ctx->enable_debug = true; + return 0; } return -EINVAL; @@ -3723,6 +3738,9 @@ static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf) if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl)) seq_puts(seq, ",mba_MBps"); + if (resctrl_debug) + seq_puts(seq, ",debug"); + return 0; } -- cgit v1.2.3