While playing with the resctrl interface I found it much
easier to deal with cpumask list rather than just regular
cpumask.
Adding cpus_list file to provide cpumask list interface
to define group's cpus.
# 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
Cc: Fenghua Yu <fenghua...@intel.com>
Cc: Peter Zijlstra <a.p.zijls...@chello.nl>
Cc: Mike Galbraith <efa...@gmx.de>
Cc: Shaohua Li <s...@fb.com>
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
Documentation/x86/intel_rdt_ui.txt | 3 +++
arch/x86/include/asm/intel_rdt.h | 5 +++++
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..7029071e2373 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": A bitmask *list* 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 3f313991c0b3..9069402f7497 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 @@ struct rdtgroup {
* @name: file name
* @mode: access mode
* @kf_ops: operations
+ * flags: 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 9ac2a5cdd9c2..56b5bdaf98e1 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -174,6 +174,13 @@ static ssize_t rdtgroup_file_write(struct kernfs_open_file
*of, char *buf,
.seq_show = rdtgroup_seqfile_show,
};
+static bool is_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_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_list(of))
+ ret = cpulist_parse(buf, newmask);
+ else
+ ret = cpumask_parse(buf, newmask);
+
if (ret)
goto unlock;
@@ -473,6 +486,14 @@ static int rdtgroup_tasks_show(struct kernfs_open_file *of,
.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,
--
1.8.3.1
