Re: [PATCH 21/32] x86/intel_rdt.h: Header for inter_rdt.c

From: Nilay Vaish
Date: Thu Jul 28 2016 - 10:08:45 EST


On 12 July 2016 at 20:02, Fenghua Yu <fenghua.yu@xxxxxxxxx> wrote:
> From: Fenghua Yu <fenghua.yu@xxxxxxxxx>
>
> The header mainly provides functions to call from the user interface
> file intel_rdt_rdtgroup.c.
>
> Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
> ---
> arch/x86/include/asm/intel_rdt.h | 87 +++++++++++++++++++++++++++++++++++++---
> 1 file changed, 81 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h
> index f2cb91d..4c5e0ac 100644
> --- a/arch/x86/include/asm/intel_rdt.h
> +++ b/arch/x86/include/asm/intel_rdt.h
> @@ -3,27 +3,99 @@
>
> #ifdef CONFIG_INTEL_RDT
>
> +#include <linux/seq_file.h>
> #include <linux/jump_label.h>
>
> -#define MAX_CBM_LENGTH 32
> #define IA32_L3_CBM_BASE 0xc90
> -#define CBM_FROM_INDEX(x) (IA32_L3_CBM_BASE + x)
> -#define MSR_IA32_PQOS_CFG 0xc81
> +#define L3_CBM_FROM_INDEX(x) (IA32_L3_CBM_BASE + x)
> +
> +#define MSR_IA32_L3_QOS_CFG 0xc81
> +
> +enum resource_type {
> + RESOURCE_L3 = 0,
> + RESOURCE_NUM = 1,
> +};
> +
> +#define MAX_CACHE_LEAVES 4
> +#define MAX_CACHE_DOMAINS 64
> +
> +DECLARE_PER_CPU_READ_MOSTLY(int, cpu_l3_domain);
> +DECLARE_PER_CPU_READ_MOSTLY(struct rdtgroup *, cpu_rdtgroup);
>
> extern struct static_key rdt_enable_key;
> void __intel_rdt_sched_in(void *dummy);
> +extern bool use_rdtgroup_tasks;
> +
> +extern bool cdp_enabled;
> +
> +struct rdt_opts {
> + bool cdp_enabled;
> + bool verbose;
> + bool simulate_cat_l3;
> +};
> +
> +struct cache_domain {
> + cpumask_t shared_cpu_map[MAX_CACHE_DOMAINS];
> + unsigned int max_cache_domains_num;
> + unsigned int level;
> + unsigned int shared_cache_id[MAX_CACHE_DOMAINS];
> +};
> +
> +extern struct rdt_opts rdt_opts;
>
> struct clos_cbm_table {
> - unsigned long l3_cbm;
> + unsigned long cbm;
> unsigned int clos_refcnt;
> };
>
> struct clos_config {
> - unsigned long *closmap;
> + unsigned long **closmap;
> u32 max_closid;
> - u32 closids_used;
> };
>
> +struct shared_domain {
> + struct cpumask cpumask;
> + int l3_domain;
> +};
> +
> +#define for_each_cache_domain(domain, start_domain, max_domain) \
> + for (domain = start_domain; domain < max_domain; domain++)
> +
> +extern struct clos_config cconfig;
> +extern struct shared_domain *shared_domain;
> +extern int shared_domain_num;
> +
> +extern struct rdtgroup *root_rdtgrp;
> +extern void rdtgroup_fork(struct task_struct *child);
> +extern void rdtgroup_post_fork(struct task_struct *child);
> +
> +extern struct clos_cbm_table **l3_cctable;
> +
> +extern unsigned int min_bitmask_len;
> +extern void msr_cpu_update(void *arg);
> +extern inline void closid_get(u32 closid, int domain);
> +extern void closid_put(u32 closid, int domain);
> +extern void closid_free(u32 closid, int domain, int level);
> +extern int closid_alloc(u32 *closid, int domain);
> +extern bool cat_l3_enabled;
> +extern unsigned int get_domain_num(int level);
> +extern struct shared_domain *shared_domain;
> +extern int shared_domain_num;
> +extern inline int get_dcbm_table_index(int x);
> +extern inline int get_icbm_table_index(int x);
> +
> +extern int get_cache_leaf(int level, int cpu);
> +
> +extern void cbm_update_l3_msr(void *pindex);
> +extern int level_to_leaf(int level);
> +
> +extern void init_msrs(bool cdpenabled);
> +extern bool cat_enabled(int level);
> +extern u64 max_cbm(int level);
> +extern u32 max_cbm_len(int level);
> +
> +extern void rdtgroup_exit(struct task_struct *tsk);
> +
> /*
> * intel_rdt_sched_in() - Writes the task's CLOSid to IA32_PQR_MSR
> *
> @@ -54,6 +126,9 @@ static inline void intel_rdt_sched_in(void)
> #else
>
> static inline void intel_rdt_sched_in(void) {}
> +static inline void rdtgroup_fork(struct task_struct *child) {}
> +static inline void rdtgroup_post_fork(struct task_struct *child) {}
> +static inline void rdtgroup_exit(struct task_struct *tsk) {}
>
> #endif
> #endif
> --
> 2.5.0
>


Hi Fenghua


There are few things about this patch that I think can be improved upon.

* some of the variables that were introduced in the first few patches
have been renamed in the later patches. Since these patches are still
not part of the kernel, I think, we should use the variable names we
want to use right from the beginning, rather than changing them midway
through the patch series.

* I think struct rdtgroup is being used before it has been declared anywhere.

* I somehow do not like this mass declaration of prototypes of all the
functions.and variables that would be used later. I think the
prototype and the implementation should be part of the same patch. If
possible, combine this patch with the ones that have the
implementations.

--
Nilay