On Fri, 2006-02-24 at 10:19, Zhang, Yanmin wrote: > On Fri, 2006-02-24 at 04:17, Luck, Tony wrote: > > > This patch exports cpu cache info which is similar to > > > /proc/pal/cpuX/cache_info. > > > > But is it similar to what i386/x86_64/anyone-else has already > > done? > Yes. The one on i386/x86_64 has attributes: > 1) level > 2) type > 3) coherency_line_size > 4) ways_of_associativity > 5) size > 6) shared_cpu_map > 7) physical_line_partition > 8) number_of_sets > > My patch doesn't have the last 2 attributes, but it has other 9 > attributes. > > > > > > One important new item is shared_cpu_map. > > > shared_cpu_map showes the cpu map sharing the cache. > > > > Looks like this could be useful for applications that want to > > pin tasks to specific cpus (or set of cpus). > > > > Some of the attributes print in a somewhat unsysfs way ... e.g. > > do we really need " cycle(s)" after the load_latency and store_latency > > value (could it ever be anything else?). Similarly "load_hints" and > > "store_hints" look unnecessarily complex for a program to parse. > > Printing sizes as 16K, 256K etc. is also good for human readability > > but worse for programs to parse. > On i386/x86_64, size also has 'K' and type is also a string. Perhaps > I could delete some attibutes, such like > load_hints/store_hints/tag_lsb/tag_msb/alias_boundary/stride, > and delete 'cycle(s)' from the output of store_latency/load_latency? > > > > > > > Finally, I count 65 new nodes in /sys per cpu on my 4-way Madison > > box (the "cache" directory, "index0" .. "index3", and then 15 attributes > > per cache level). >From sysfs implementation point of view, attribute couldn't be counted as node, so there is 5 nodes per cpu on your 4-way Madison box. > So when SGI start making use of the CONFIG_NR_CPUS=1024 > > that we recently added, they can look forward to 66560[1] more nodes So there would be 5*1024 nodes on SGI machine. > > in /sys ... is this the best way to export this information? Do we > > really need to add all of these to the user-kernel API (see long > > discussion thread on LKML about how you can't change this once you > > add it). Should we keep ia64 consistent with i386/x86_64? i386/x86_64 already exports cache info by the same approach. > It's a problem. It could be mitigated by deleting some attributes, > but couldn't be resolved thoroughly. I deleted 7 attributes which also save some spaces. > > > > [1] Actually it will be worse than this as Montecito has split I&D > > cache at the mid-level instead of combined, so there will be five > > "index" directories and a total of 81 nodes/cpu => 82944 total. If don't count attributes, there would be 6 nodes/cpu => 6*1024 total on Montecito. Bebow new patch exports 8 attributes: 1) level 2) type 3) coherency_line_size 4) ways_of_associativity 5) size 6) shared_cpu_map 7) stride 8) attributes Signed-off-by: Zhang Yanmin <yanmin.zhang@xxxxxxxxx> --- diff -Nraup linux-2.6.16-rc4/arch/ia64/kernel/topology.c linux-2.6.16-rc4_fix/arch/ia64/kernel/topology.c --- linux-2.6.16-rc4/arch/ia64/kernel/topology.c 2006-02-18 03:53:15.000000000 +0800 +++ linux-2.6.16-rc4_fix/arch/ia64/kernel/topology.c 2006-02-18 04:02:48.000000000 +0800 @@ -9,6 +9,8 @@ * 2002/08/07 Erich Focht <efocht@xxxxxxxxxx> * Populate cpu entries in sysfs for non-numa systems as well * Intel Corporation - Ashok Raj + * 01/05/2006 Zhang, Yanmin + * Populate cpu cache entries in sysfs for cpu cache info */ #include <linux/config.h> @@ -19,6 +21,7 @@ #include <linux/init.h> #include <linux/bootmem.h> #include <linux/nodemask.h> +#include <linux/notifier.h> #include <asm/mmzone.h> #include <asm/numa.h> #include <asm/cpu.h> @@ -101,3 +104,367 @@ out: } subsys_initcall(topology_init); + + +#ifdef CONFIG_SYSFS + +/* + * Export cpu cache information through sysfs + */ + +/* + * A bunch of string array to get pretty printing + */ +static const char *cache_types[] = { + "", /* not used */ + "Instruction", + "Data", + "Data/Instruction" /* unified */ +}; + +static const char *cache_mattrib[]={ + "WriteThrough", + "WriteBack", + "", /* reserved */ + "" /* reserved */ +}; + +struct cache_info { + pal_cache_config_info_t cci; + cpumask_t shared_cpu_map; + int level; + int type; + struct kobject kobj; +}; + +struct cpu_cache_info { + struct cache_info *cache_leaves; + int num_cache_leaves; + struct kobject kobj; +}; + +static struct cpu_cache_info all_cpu_cache_info[NR_CPUS]; +#define LEAF_KOBJECT_PTR(x,y) (&all_cpu_cache_info[x].cache_leaves[y]) + +#ifdef CONFIG_SMP +static void cache_shared_cpu_map_setup( unsigned int cpu, + struct cache_info * this_leaf) +{ + pal_cache_shared_info_t csi; + int num_shared, i = 0; + unsigned int j; + + if (cpu_data(cpu)->threads_per_core <= 1 && + cpu_data(cpu)->cores_per_socket <= 1) { + cpu_set(cpu, this_leaf->shared_cpu_map); + return; + } + + if (ia64_pal_cache_shared_info(this_leaf->level, + this_leaf->type, + 0, + &csi) != PAL_STATUS_SUCCESS) + return; + + num_shared = (int) csi.num_shared; + do { + for_each_cpu(j) + if (cpu_data(cpu)->socket_id == cpu_data(j)->socket_id + && cpu_data(j)->core_id == csi.log1_cid + && cpu_data(j)->thread_id == csi.log1_tid) + cpu_set(j, this_leaf->shared_cpu_map); + + i++; + } while (i < num_shared && + ia64_pal_cache_shared_info(this_leaf->level, + this_leaf->type, + i, + &csi) == PAL_STATUS_SUCCESS); +} +#else +static void cache_shared_cpu_map_setup(unsigned int cpu, + struct cache_info * this_leaf) +{ + cpu_set(cpu, this_leaf->shared_cpu_map); + return; +} +#endif + +static ssize_t show_coherency_line_size(struct cache_info *this_leaf, + char *buf) +{ + return sprintf(buf, "%u\n", 1 << this_leaf->cci.pcci_line_size); +} + +static ssize_t show_ways_of_associativity(struct cache_info *this_leaf, + char *buf) +{ + return sprintf(buf, "%u\n", this_leaf->cci.pcci_assoc); +} + +static ssize_t show_stride(struct cache_info *this_leaf, char *buf) +{ + return sprintf(buf, "%d\n", 1 << this_leaf->cci.pcci_stride); +} + +static ssize_t show_attributes(struct cache_info *this_leaf, char *buf) +{ + return sprintf(buf, + "%s\n", + cache_mattrib[this_leaf->cci.pcci_cache_attr]); +} + +static ssize_t show_size(struct cache_info *this_leaf, char *buf) +{ + return sprintf(buf, "%luK\n", this_leaf->cci.pcci_cache_size / 1024); +} + +static ssize_t show_shared_cpu_map(struct cache_info *this_leaf, char *buf) +{ + ssize_t len; + cpumask_t shared_cpu_map; + + cpus_and(shared_cpu_map, this_leaf->shared_cpu_map, cpu_online_map); + len = cpumask_scnprintf(buf, NR_CPUS+1, shared_cpu_map); + len += sprintf(buf+len, "\n"); + return len; +} + +static ssize_t show_type(struct cache_info *this_leaf, char *buf) +{ + int type = this_leaf->type + this_leaf->cci.pcci_unified; + return sprintf(buf, "%s\n", cache_types[type]); +} + +static ssize_t show_level(struct cache_info *this_leaf, char *buf) +{ + return sprintf(buf, "%u\n", this_leaf->level); +} + +struct cache_attr { + struct attribute attr; + ssize_t (*show)(struct cache_info *, char *); + ssize_t (*store)(struct cache_info *, const char *, size_t count); +}; + +#ifdef define_one_ro + #undef define_one_ro +#endif +#define define_one_ro(_name) \ + static struct cache_attr _name = \ +__ATTR(_name, 0444, show_##_name, NULL) + +define_one_ro(level); +define_one_ro(type); +define_one_ro(coherency_line_size); +define_one_ro(stride); +define_one_ro(ways_of_associativity); +define_one_ro(size); +define_one_ro(shared_cpu_map); +define_one_ro(attributes); + +static struct attribute * cache_default_attrs[] = { + &type.attr, + &level.attr, + &coherency_line_size.attr, + &stride.attr, + &ways_of_associativity.attr, + &attributes.attr, + &size.attr, + &shared_cpu_map.attr, + NULL +}; + +#define to_object(k) container_of(k, struct cache_info, kobj) +#define to_attr(a) container_of(a, struct cache_attr, attr) + +static ssize_t cache_show(struct kobject * kobj, struct attribute * attr, char * buf) +{ + struct cache_attr *fattr = to_attr(attr); + struct cache_info *this_leaf = to_object(kobj); + ssize_t ret; + + ret = fattr->show ? fattr->show(this_leaf, buf) : 0; + return ret; +} + +static struct sysfs_ops cache_sysfs_ops = { + .show = cache_show +}; + +static struct kobj_type cache_ktype = { + .sysfs_ops = &cache_sysfs_ops, + .default_attrs = cache_default_attrs, +}; + +static struct kobj_type cache_ktype_percpu_entry = { + .sysfs_ops = &cache_sysfs_ops, +}; + +static void __cpuinit cpu_cache_sysfs_exit(unsigned int cpu) +{ + if (all_cpu_cache_info[cpu].cache_leaves) { + kfree(all_cpu_cache_info[cpu].cache_leaves); + all_cpu_cache_info[cpu].cache_leaves = NULL; + } + all_cpu_cache_info[cpu].num_cache_leaves = 0; + memset(&all_cpu_cache_info[cpu].kobj, 0, sizeof(struct kobject)); + + return; +} + +static int __cpuinit cpu_cache_sysfs_init(unsigned int cpu) +{ + u64 i, levels, unique_caches; + pal_cache_config_info_t cci; + int j; + s64 status; + struct cache_info *this_cache; + int num_cache_leaves = 0; + + if ((status = ia64_pal_cache_summary(&levels, &unique_caches)) != 0) { + printk(KERN_ERR "ia64_pal_cache_summary=%ld\n", status); + return -1; + } + + this_cache=kzalloc(sizeof(struct cache_info)*unique_caches, + GFP_KERNEL); + if (this_cache == NULL) + return -ENOMEM; + + for (i=0; i < levels; i++) { + for (j=2; j >0 ; j--) { + if ((status=ia64_pal_cache_config_info(i,j, &cci)) != + PAL_STATUS_SUCCESS) + continue; + + this_cache[num_cache_leaves].cci = cci; + this_cache[num_cache_leaves].level = i; + this_cache[num_cache_leaves].type = j; + + cache_shared_cpu_map_setup(cpu, + &this_cache[num_cache_leaves]); + num_cache_leaves ++; + } + } + + all_cpu_cache_info[cpu].cache_leaves = this_cache; + all_cpu_cache_info[cpu].num_cache_leaves = num_cache_leaves; + + memset(&all_cpu_cache_info[cpu].kobj, 0, sizeof(struct kobject)); + + return 0; +} + +/* Add cache interface for CPU device */ +static int __cpuinit cache_add_dev(struct sys_device * sys_dev) +{ + unsigned int cpu = sys_dev->id; + unsigned long i, j; + struct cache_info *this_object; + int retval = 0; + cpumask_t oldmask; + + if (all_cpu_cache_info[cpu].kobj.parent) + return 0; + + oldmask = current->cpus_allowed; + retval = set_cpus_allowed(current, cpumask_of_cpu(cpu)); + if (unlikely(retval)) + return retval; + + retval = cpu_cache_sysfs_init(cpu); + set_cpus_allowed(current, oldmask); + if (unlikely(retval < 0)) + return retval; + + all_cpu_cache_info[cpu].kobj.parent = &sys_dev->kobj; + kobject_set_name(&all_cpu_cache_info[cpu].kobj, "%s", "cache"); + all_cpu_cache_info[cpu].kobj.ktype = &cache_ktype_percpu_entry; + retval = kobject_register(&all_cpu_cache_info[cpu].kobj); + + for (i = 0; i < all_cpu_cache_info[cpu].num_cache_leaves; i++) { + this_object = LEAF_KOBJECT_PTR(cpu,i); + this_object->kobj.parent = &all_cpu_cache_info[cpu].kobj; + kobject_set_name(&(this_object->kobj), "index%1lu", i); + this_object->kobj.ktype = &cache_ktype; + retval = kobject_register(&(this_object->kobj)); + if (unlikely(retval)) { + for (j = 0; j < i; j++) { + kobject_unregister( + &(LEAF_KOBJECT_PTR(cpu,j)->kobj)); + } + kobject_unregister(&all_cpu_cache_info[cpu].kobj); + cpu_cache_sysfs_exit(cpu); + break; + } + } + return retval; +} + +/* Remove cache interface for CPU device */ +static int __cpuinit cache_remove_dev(struct sys_device * sys_dev) +{ + unsigned int cpu = sys_dev->id; + unsigned long i; + + for (i = 0; i < all_cpu_cache_info[cpu].num_cache_leaves; i++) + kobject_unregister(&(LEAF_KOBJECT_PTR(cpu,i)->kobj)); + + if (all_cpu_cache_info[cpu].kobj.parent) { + kobject_unregister(&all_cpu_cache_info[cpu].kobj); + memset(&all_cpu_cache_info[cpu].kobj, + 0, + sizeof(struct kobject)); + } + + cpu_cache_sysfs_exit(cpu); + + return 0; +} + +/* + * When a cpu is hot-plugged, do a check and initiate + * cache kobject if necessary + */ +static int __cpuinit cache_cpu_callback(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + unsigned int cpu = (unsigned long)hcpu; + struct sys_device *sys_dev; + + sys_dev = get_cpu_sysdev(cpu); + switch (action) { + case CPU_ONLINE: + cache_add_dev(sys_dev); + break; + case CPU_DEAD: + cache_remove_dev(sys_dev); + break; + } + return NOTIFY_OK; +} + +static struct notifier_block cache_cpu_notifier = +{ + .notifier_call = cache_cpu_callback +}; + +static int __cpuinit cache_sysfs_init(void) +{ + int i; + + for_each_online_cpu(i) { + cache_cpu_callback(&cache_cpu_notifier, CPU_ONLINE, + (void *)(long)i); + } + + register_cpu_notifier(&cache_cpu_notifier); + + return 0; +} + +device_initcall(cache_sysfs_init); + +#endif //CONFIG_SYSFS + diff -Nraup linux-2.6.16-rc4/include/asm-ia64/pal.h linux-2.6.16-rc4_fix/include/asm-ia64/pal.h --- linux-2.6.16-rc4/include/asm-ia64/pal.h 2006-02-18 03:53:14.000000000 +0800 +++ linux-2.6.16-rc4_fix/include/asm-ia64/pal.h 2006-02-18 03:55:00.000000000 +0800 @@ -68,6 +68,7 @@ #define PAL_SHUTDOWN 40 /* enter processor shutdown state */ #define PAL_PREFETCH_VISIBILITY 41 /* Make Processor Prefetches Visible */ #define PAL_LOGICAL_TO_PHYSICAL 42 /* returns information on logical to physical processor mapping */ +#define PAL_CACHE_SHARED_INFO 43 /* returns information on caches shared by logical processor */ #define PAL_COPY_PAL 256 /* relocate PAL procedures and PAL PMI */ #define PAL_HALT_INFO 257 /* return the low power capabilities of processor */ @@ -1648,6 +1649,33 @@ ia64_pal_logical_to_phys(u64 proc_number return iprv.status; } + +typedef struct pal_cache_shared_info_s +{ + u64 num_shared; + pal_proc_n_log_info1_t ppli1; + pal_proc_n_log_info2_t ppli2; +} pal_cache_shared_info_t; + +/* Get information on logical to physical processor mappings. */ +static inline s64 +ia64_pal_cache_shared_info(u64 level, + u64 type, + u64 proc_number, + pal_cache_shared_info_t *info) +{ + struct ia64_pal_retval iprv; + + PAL_CALL(iprv, PAL_CACHE_SHARED_INFO, level, type, proc_number); + + if (iprv.status == PAL_STATUS_SUCCESS) { + info->num_shared = iprv.v0; + info->ppli1.ppli1_data = iprv.v1; + info->ppli2.ppli2_data = iprv.v2; + } + + return iprv.status; +} #endif /* __ASSEMBLY__ */ #endif /* _ASM_IA64_PAL_H */ - : send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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