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author | Jiri Olsa <jolsa@redhat.com> | 2017-04-10 16:52:32 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2017-04-10 19:10:25 +0200 |
commit | 4ffa3c977b5da2907eb294dc6d0259a02f2284aa (patch) | |
tree | 7267158eb409425c430d92efcfd529757ed436cb | |
parent | 17f8ba1dca072ce66c25b9e74ea2500b029594a0 (diff) | |
download | linux-4ffa3c977b5da2907eb294dc6d0259a02f2284aa.tar.bz2 |
x86/intel_rdt: Add cpus_list rdtgroup file
The resource control filesystem provides only a bitmask based cpus file for
assigning CPUs to a resource group. That's cumbersome with large cpumasks
and non-intuitive when modifying the file from the command line.
Range based cpu lists are commonly used along with bitmask based cpu files
in various subsystems throughout the kernel.
Add 'cpus_list' file which is CPU range based.
# cd /sys/fs/resctrl/
# echo 1-10 > krava/cpus_list
# cat krava/cpus_list
1-10
# cat krava/cpus
0007fe
# cat cpus
fffff9
# cat cpus_list
0,3-23
[ tglx: Massaged changelog and replaced "bitmask lists" by "CPU ranges" ]
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Shaohua Li <shli@fb.com>
Link: http://lkml.kernel.org/r/20170410145232.GF25354@krava
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r-- | Documentation/x86/intel_rdt_ui.txt | 3 | ||||
-rw-r--r-- | arch/x86/include/asm/intel_rdt.h | 5 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 29 |
3 files changed, 33 insertions, 4 deletions
diff --git a/Documentation/x86/intel_rdt_ui.txt b/Documentation/x86/intel_rdt_ui.txt index 3ea198460469..a1ace91c4b86 100644 --- a/Documentation/x86/intel_rdt_ui.txt +++ b/Documentation/x86/intel_rdt_ui.txt @@ -59,6 +59,9 @@ There are three files associated with each group: given to the default (root) group. You cannot remove CPUs from the default group. +"cpus_list": One or more CPU ranges of logical CPUs assigned to this + group. Same rules apply like for the "cpus" file. + "schemata": A list of all the resources available to this group. Each resource has its own line and format - see below for details. diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h index 9030bcccb717..611c82306fdf 100644 --- a/arch/x86/include/asm/intel_rdt.h +++ b/arch/x86/include/asm/intel_rdt.h @@ -37,6 +37,9 @@ struct rdtgroup { /* rdtgroup.flags */ #define RDT_DELETED 1 +/* rftype.flags */ +#define RFTYPE_FLAGS_CPUS_LIST 1 + /* List of all resource groups */ extern struct list_head rdt_all_groups; @@ -49,6 +52,7 @@ int __init rdtgroup_init(void); * @name: File name * @mode: Access mode * @kf_ops: File operations + * @flags: File specific RFTYPE_FLAGS_* flags * @seq_show: Show content of the file * @write: Write to the file */ @@ -56,6 +60,7 @@ struct rftype { char *name; umode_t mode; struct kernfs_ops *kf_ops; + unsigned long flags; int (*seq_show)(struct kernfs_open_file *of, struct seq_file *sf, void *v); diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c index c05509d38b1f..8401cf5cc239 100644 --- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -174,6 +174,13 @@ static struct kernfs_ops rdtgroup_kf_single_ops = { .seq_show = rdtgroup_seqfile_show, }; +static bool is_cpu_list(struct kernfs_open_file *of) +{ + struct rftype *rft = of->kn->priv; + + return rft->flags & RFTYPE_FLAGS_CPUS_LIST; +} + static int rdtgroup_cpus_show(struct kernfs_open_file *of, struct seq_file *s, void *v) { @@ -182,10 +189,12 @@ static int rdtgroup_cpus_show(struct kernfs_open_file *of, rdtgrp = rdtgroup_kn_lock_live(of->kn); - if (rdtgrp) - seq_printf(s, "%*pb\n", cpumask_pr_args(&rdtgrp->cpu_mask)); - else + if (rdtgrp) { + seq_printf(s, is_cpu_list(of) ? "%*pbl\n" : "%*pb\n", + cpumask_pr_args(&rdtgrp->cpu_mask)); + } else { ret = -ENOENT; + } rdtgroup_kn_unlock(of->kn); return ret; @@ -252,7 +261,11 @@ static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of, goto unlock; } - ret = cpumask_parse(buf, newmask); + if (is_cpu_list(of)) + ret = cpulist_parse(buf, newmask); + else + ret = cpumask_parse(buf, newmask); + if (ret) goto unlock; @@ -473,6 +486,14 @@ static struct rftype rdtgroup_base_files[] = { .seq_show = rdtgroup_cpus_show, }, { + .name = "cpus_list", + .mode = 0644, + .kf_ops = &rdtgroup_kf_single_ops, + .write = rdtgroup_cpus_write, + .seq_show = rdtgroup_cpus_show, + .flags = RFTYPE_FLAGS_CPUS_LIST, + }, + { .name = "tasks", .mode = 0644, .kf_ops = &rdtgroup_kf_single_ops, |