diff options
| -rw-r--r-- | Documentation/x86/intel_rdt_ui.txt | 14 | ||||
| -rw-r--r-- | arch/x86/include/asm/intel_rdt.h | 10 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt_schemata.c | 76 |
4 files changed, 51 insertions, 51 deletions
diff --git a/Documentation/x86/intel_rdt_ui.txt b/Documentation/x86/intel_rdt_ui.txt index 51cf6fa5591f..3ea198460469 100644 --- a/Documentation/x86/intel_rdt_ui.txt +++ b/Documentation/x86/intel_rdt_ui.txt @@ -129,6 +129,20 @@ schemata format is always: L2:<cache_id0>=<cbm>;<cache_id1>=<cbm>;... +Reading/writing the schemata file +--------------------------------- +Reading the schemata file will show the state of all resources +on all domains. When writing you only need to specify those values +which you wish to change. E.g. + +# cat schemata +L3DATA:0=fffff;1=fffff;2=fffff;3=fffff +L3CODE:0=fffff;1=fffff;2=fffff;3=fffff +# echo "L3DATA:2=3c0;" > schemata +# cat schemata +L3DATA:0=fffff;1=fffff;2=3c0;3=fffff +L3CODE:0=fffff;1=fffff;2=fffff;3=fffff + Example 1 --------- On a two socket machine (one L3 cache per socket) with just four bits diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h index 0d64397cee58..d7705270c401 100644 --- a/arch/x86/include/asm/intel_rdt.h +++ b/arch/x86/include/asm/intel_rdt.h @@ -76,10 +76,7 @@ struct rftype { * @min_cbm_bits: Minimum number of consecutive bits to be set * in a cache bit mask * @domains: All domains for this resource - * @num_domains: Number of domains active * @msr_base: Base MSR address for CBMs - * @tmp_cbms: Scratch space when updating schemata - * @num_tmp_cbms: Number of CBMs in tmp_cbms * @cache_level: Which cache level defines scope of this domain * @cbm_idx_multi: Multiplier of CBM index * @cbm_idx_offset: Offset of CBM index. CBM index is computed by: @@ -94,10 +91,7 @@ struct rdt_resource { int min_cbm_bits; u32 max_cbm; struct list_head domains; - int num_domains; int msr_base; - u32 *tmp_cbms; - int num_tmp_cbms; int cache_level; int cbm_idx_multi; int cbm_idx_offset; @@ -109,12 +103,16 @@ struct rdt_resource { * @id: unique id for this instance * @cpu_mask: which cpus share this resource * @cbm: array of cache bit masks (indexed by CLOSID) + * @new_cbm: new cbm value to be loaded + * @have_new_cbm: did user provide new_cbm for this domain */ struct rdt_domain { struct list_head list; int id; struct cpumask cpu_mask; u32 *cbm; + u32 new_cbm; + bool have_new_cbm; }; /** diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c index 5a533fefefa0..329b8876b984 100644 --- a/arch/x86/kernel/cpu/intel_rdt.c +++ b/arch/x86/kernel/cpu/intel_rdt.c @@ -309,7 +309,6 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r) cpumask_set_cpu(cpu, &d->cpu_mask); list_add_tail(&d->list, add_pos); - r->num_domains++; } static void domain_remove_cpu(int cpu, struct rdt_resource *r) @@ -325,7 +324,6 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r) cpumask_clear_cpu(cpu, &d->cpu_mask); if (cpumask_empty(&d->cpu_mask)) { - r->num_domains--; kfree(d->cbm); list_del(&d->list); kfree(d); diff --git a/arch/x86/kernel/cpu/intel_rdt_schemata.c b/arch/x86/kernel/cpu/intel_rdt_schemata.c index f369cb8db0d5..52e83eabd9b7 100644 --- a/arch/x86/kernel/cpu/intel_rdt_schemata.c +++ b/arch/x86/kernel/cpu/intel_rdt_schemata.c @@ -56,17 +56,21 @@ static bool cbm_validate(unsigned long var, struct rdt_resource *r) * Read one cache bit mask (hex). Check that it is valid for the current * resource type. */ -static int parse_cbm(char *buf, struct rdt_resource *r) +static int parse_cbm(char *buf, struct rdt_resource *r, struct rdt_domain *d) { unsigned long data; int ret; + if (d->have_new_cbm) + return -EINVAL; + ret = kstrtoul(buf, 16, &data); if (ret) return ret; if (!cbm_validate(data, r)) return -EINVAL; - r->tmp_cbms[r->num_tmp_cbms++] = data; + d->new_cbm = data; + d->have_new_cbm = true; return 0; } @@ -74,8 +78,8 @@ static int parse_cbm(char *buf, struct rdt_resource *r) /* * For each domain in this resource we expect to find a series of: * id=mask - * separated by ";". The "id" is in decimal, and must appear in the - * right order. + * separated by ";". The "id" is in decimal, and must match one of + * the "id"s for this resource. */ static int parse_line(char *line, struct rdt_resource *r) { @@ -83,21 +87,21 @@ static int parse_line(char *line, struct rdt_resource *r) struct rdt_domain *d; unsigned long dom_id; +next: + if (!line || line[0] == '\0') + return 0; + dom = strsep(&line, ";"); + id = strsep(&dom, "="); + if (!dom || kstrtoul(id, 10, &dom_id)) + return -EINVAL; list_for_each_entry(d, &r->domains, list) { - dom = strsep(&line, ";"); - if (!dom) - return -EINVAL; - id = strsep(&dom, "="); - if (kstrtoul(id, 10, &dom_id) || dom_id != d->id) - return -EINVAL; - if (parse_cbm(dom, r)) - return -EINVAL; + if (d->id == dom_id) { + if (parse_cbm(dom, r, d)) + return -EINVAL; + goto next; + } } - - /* Any garbage at the end of the line? */ - if (line && line[0]) - return -EINVAL; - return 0; + return -EINVAL; } static int update_domains(struct rdt_resource *r, int closid) @@ -105,7 +109,7 @@ static int update_domains(struct rdt_resource *r, int closid) struct msr_param msr_param; cpumask_var_t cpu_mask; struct rdt_domain *d; - int cpu, idx = 0; + int cpu; if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) return -ENOMEM; @@ -115,9 +119,13 @@ static int update_domains(struct rdt_resource *r, int closid) msr_param.res = r; list_for_each_entry(d, &r->domains, list) { - cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); - d->cbm[msr_param.low] = r->tmp_cbms[idx++]; + if (d->have_new_cbm && d->new_cbm != d->cbm[closid]) { + cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); + d->cbm[closid] = d->new_cbm; + } } + if (cpumask_empty(cpu_mask)) + goto done; cpu = get_cpu(); /* Update CBM on this cpu if it's in cpu_mask. */ if (cpumask_test_cpu(cpu, cpu_mask)) @@ -126,6 +134,7 @@ static int update_domains(struct rdt_resource *r, int closid) smp_call_function_many(cpu_mask, rdt_cbm_update, &msr_param, 1); put_cpu(); +done: free_cpumask_var(cpu_mask); return 0; @@ -135,10 +144,10 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct rdtgroup *rdtgrp; + struct rdt_domain *dom; struct rdt_resource *r; char *tok, *resname; int closid, ret = 0; - u32 *l3_cbms = NULL; /* Valid input requires a trailing newline */ if (nbytes == 0 || buf[nbytes - 1] != '\n') @@ -153,16 +162,9 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, closid = rdtgrp->closid; - /* get scratch space to save all the masks while we validate input */ - for_each_enabled_rdt_resource(r) { - r->tmp_cbms = kcalloc(r->num_domains, sizeof(*l3_cbms), - GFP_KERNEL); - if (!r->tmp_cbms) { - ret = -ENOMEM; - goto out; - } - r->num_tmp_cbms = 0; - } + for_each_enabled_rdt_resource(r) + list_for_each_entry(dom, &r->domains, list) + dom->have_new_cbm = false; while ((tok = strsep(&buf, "\n")) != NULL) { resname = strsep(&tok, ":"); @@ -185,14 +187,6 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, } } - /* Did the parser find all the masks we need? */ - for_each_enabled_rdt_resource(r) { - if (r->num_tmp_cbms != r->num_domains) { - ret = -EINVAL; - goto out; - } - } - for_each_enabled_rdt_resource(r) { ret = update_domains(r, closid); if (ret) @@ -201,10 +195,6 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, out: rdtgroup_kn_unlock(of->kn); - for_each_enabled_rdt_resource(r) { - kfree(r->tmp_cbms); - r->tmp_cbms = NULL; - } return ret ?: nbytes; } |