Specify a new mount option "mba_MB" to enable the user to specify MBA bandwidth in Megabytes(Software Controller/SC) instead of b/w percentage:
$mount -t resctrl resctrl [-o cdp[,cdpl2][mba_MB]] /sys/fs/resctrl Signed-off-by: Vikas Shivappa <[email protected]> --- arch/x86/kernel/cpu/intel_rdt.h | 5 +++++ arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 31 +++++++++++++++++++++++++++++-- 2 files changed, 34 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h index 3fd7a70..3e9bc3f 100644 --- a/arch/x86/kernel/cpu/intel_rdt.h +++ b/arch/x86/kernel/cpu/intel_rdt.h @@ -259,6 +259,7 @@ struct rdt_cache { * @min_bw: Minimum memory bandwidth percentage user can request * @bw_gran: Granularity at which the memory bandwidth is allocated * @delay_linear: True if memory B/W delay is in linear scale + * @bw_byte: True if memory B/W is specified in bytes * @mb_map: Mapping of memory B/W percentage to memory B/W delay */ struct rdt_membw { @@ -266,6 +267,7 @@ struct rdt_membw { u32 min_bw; u32 bw_gran; u32 delay_linear; + bool bw_byte; u32 *mb_map; }; @@ -295,6 +297,9 @@ static inline bool is_mbm_event(int e) e <= QOS_L3_MBM_LOCAL_EVENT_ID); } +#define is_mba_linear() rdt_resources_all[RDT_RESOURCE_MBA].membw.delay_linear +#define is_mba_MBctrl() rdt_resources_all[RDT_RESOURCE_MBA].membw.bw_byte + /** * struct rdt_resource - attributes of an RDT resource * @rid: The index of the resource diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c index fca759d..0707191 100644 --- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -1041,6 +1041,24 @@ static int set_cache_qos_cfg(int level, bool enable) return 0; } +static void __set_mba_byte_ctrl(bool byte_ctrl) +{ + struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA]; + + r->membw.bw_byte = byte_ctrl; +} + +/* + * MBA allocation in bytes is only supported if + * MBM is supported and MBA is in linear scale. +*/ +static void set_mba_byte_ctrl(bool byte_ctrl) +{ + if ((is_mbm_enabled() && is_mba_linear()) && + byte_ctrl != is_mba_MBctrl()) + __set_mba_byte_ctrl(byte_ctrl); +} + static int cdp_enable(int level, int data_type, int code_type) { struct rdt_resource *r_ldata = &rdt_resources_all[data_type]; @@ -1104,7 +1122,7 @@ static void cdp_disable_all(void) cdpl2_disable(); } -static int parse_rdtgroupfs_options(char *data) +static int parse_rdtgroupfs_options(char *data, bool *mba_MBctrl) { char *token, *o = data; int ret = 0; @@ -1123,6 +1141,8 @@ static int parse_rdtgroupfs_options(char *data) ret = cdpl2_enable(); if (ret) goto out; + } else if (!strcmp(token, "mba_MB")) { + *mba_MBctrl = true; } else { ret = -EINVAL; goto out; @@ -1209,6 +1229,7 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type, int flags, const char *unused_dev_name, void *data) { + bool mba_MBctrl = false; struct rdt_domain *dom; struct rdt_resource *r; struct dentry *dentry; @@ -1224,7 +1245,7 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type, goto out; } - ret = parse_rdtgroupfs_options(data); + ret = parse_rdtgroupfs_options(data, &mba_MBctrl); if (ret) { dentry = ERR_PTR(ret); goto out_cdp; @@ -1277,6 +1298,9 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type, mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL); } + if (mba_MBctrl) + set_mba_byte_ctrl(true); + goto out; out_mondata: @@ -1445,6 +1469,9 @@ static void rdt_kill_sb(struct super_block *sb) cpus_read_lock(); mutex_lock(&rdtgroup_mutex); + /*Set the control values before the rest of reset*/ + set_mba_byte_ctrl(false); + /*Put everything back to default values. */ for_each_alloc_enabled_rdt_resource(r) reset_all_ctrls(r); -- 1.9.1
