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authorSteven Rostedt (Red Hat) <rostedt@goodmis.org>2016-02-22 22:26:50 +0100
committerIngo Molnar <mingo@kernel.org>2016-02-29 09:53:06 +0100
commitd6ca41d7922ce0110a840ef4f8ec4afdd5a239d3 (patch)
tree0dd1302f3f1dfb8a429f76147c66db4998488344 /kernel/sched/debug.c
parentsched/rt: Fix PI handling vs. sched_setscheduler() (diff)
downloadlinux-d6ca41d7922ce0110a840ef4f8ec4afdd5a239d3.tar.xz
linux-d6ca41d7922ce0110a840ef4f8ec4afdd5a239d3.zip
sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c
As /sys/kernel/debug/sched_features is only created when SCHED_DEBUG is enabled, and the file debug.c is only compiled when SCHED_DEBUG is enabled, it makes sense to move sched_feature setup into that file and get rid of the #ifdef. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160222212825.464193063@goodmis.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/debug.c')
-rw-r--r--kernel/sched/debug.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 7cfa87bd8b89..d2dedfcbf84d 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -16,6 +16,7 @@
#include <linux/kallsyms.h>
#include <linux/utsname.h>
#include <linux/mempolicy.h>
+#include <linux/debugfs.h>
#include "sched.h"
@@ -58,6 +59,136 @@ static unsigned long nsec_low(unsigned long long nsec)
#define SPLIT_NS(x) nsec_high(x), nsec_low(x)
+#define SCHED_FEAT(name, enabled) \
+ #name ,
+
+static const char * const sched_feat_names[] = {
+#include "features.h"
+};
+
+#undef SCHED_FEAT
+
+static int sched_feat_show(struct seq_file *m, void *v)
+{
+ int i;
+
+ for (i = 0; i < __SCHED_FEAT_NR; i++) {
+ if (!(sysctl_sched_features & (1UL << i)))
+ seq_puts(m, "NO_");
+ seq_printf(m, "%s ", sched_feat_names[i]);
+ }
+ seq_puts(m, "\n");
+
+ return 0;
+}
+
+#ifdef HAVE_JUMP_LABEL
+
+#define jump_label_key__true STATIC_KEY_INIT_TRUE
+#define jump_label_key__false STATIC_KEY_INIT_FALSE
+
+#define SCHED_FEAT(name, enabled) \
+ jump_label_key__##enabled ,
+
+struct static_key sched_feat_keys[__SCHED_FEAT_NR] = {
+#include "features.h"
+};
+
+#undef SCHED_FEAT
+
+static void sched_feat_disable(int i)
+{
+ static_key_disable(&sched_feat_keys[i]);
+}
+
+static void sched_feat_enable(int i)
+{
+ static_key_enable(&sched_feat_keys[i]);
+}
+#else
+static void sched_feat_disable(int i) { };
+static void sched_feat_enable(int i) { };
+#endif /* HAVE_JUMP_LABEL */
+
+static int sched_feat_set(char *cmp)
+{
+ int i;
+ int neg = 0;
+
+ if (strncmp(cmp, "NO_", 3) == 0) {
+ neg = 1;
+ cmp += 3;
+ }
+
+ for (i = 0; i < __SCHED_FEAT_NR; i++) {
+ if (strcmp(cmp, sched_feat_names[i]) == 0) {
+ if (neg) {
+ sysctl_sched_features &= ~(1UL << i);
+ sched_feat_disable(i);
+ } else {
+ sysctl_sched_features |= (1UL << i);
+ sched_feat_enable(i);
+ }
+ break;
+ }
+ }
+
+ return i;
+}
+
+static ssize_t
+sched_feat_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ char *cmp;
+ int i;
+ struct inode *inode;
+
+ if (cnt > 63)
+ cnt = 63;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+ cmp = strstrip(buf);
+
+ /* Ensure the static_key remains in a consistent state */
+ inode = file_inode(filp);
+ inode_lock(inode);
+ i = sched_feat_set(cmp);
+ inode_unlock(inode);
+ if (i == __SCHED_FEAT_NR)
+ return -EINVAL;
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static int sched_feat_open(struct inode *inode, struct file *filp)
+{
+ return single_open(filp, sched_feat_show, NULL);
+}
+
+static const struct file_operations sched_feat_fops = {
+ .open = sched_feat_open,
+ .write = sched_feat_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static __init int sched_init_debug(void)
+{
+ debugfs_create_file("sched_features", 0644, NULL, NULL,
+ &sched_feat_fops);
+
+ return 0;
+}
+late_initcall(sched_init_debug);
+
#ifdef CONFIG_FAIR_GROUP_SCHED
static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
{