From f00b45c145981b43c7e7f66315ac77534c938cbf Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sat, 19 Apr 2008 19:45:00 +0200 Subject: [PATCH] sched: /debug/sched_features provide a text based interface to the scheduler features; this saves the 'user' from setting bits using decimal arithmetic. Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- kernel/sched.c | 162 ++++++++++++++++++++++++++++++++++------ kernel/sched_features.h | 10 +++ 2 files changed, 150 insertions(+), 22 deletions(-) create mode 100644 kernel/sched_features.h diff --git a/kernel/sched.c b/kernel/sched.c index 8f03817e7d..b59a44e1ea 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -68,6 +68,8 @@ #include #include #include +#include +#include #include #include @@ -732,32 +734,148 @@ static void update_rq_clock(struct rq *rq) /* * Debugging: various feature bits */ + +#define SCHED_FEAT(name, enabled) \ + __SCHED_FEAT_##name , + enum { - SCHED_FEAT_NEW_FAIR_SLEEPERS = 1, - SCHED_FEAT_WAKEUP_PREEMPT = 2, - SCHED_FEAT_START_DEBIT = 4, - SCHED_FEAT_AFFINE_WAKEUPS = 8, - SCHED_FEAT_CACHE_HOT_BUDDY = 16, - SCHED_FEAT_SYNC_WAKEUPS = 32, - SCHED_FEAT_HRTICK = 64, - SCHED_FEAT_DOUBLE_TICK = 128, - SCHED_FEAT_NORMALIZED_SLEEPER = 256, - SCHED_FEAT_DEADLINE = 512, +#include "sched_features.h" }; +#undef SCHED_FEAT + +#define SCHED_FEAT(name, enabled) \ + (1UL << __SCHED_FEAT_##name) * enabled | + const_debug unsigned int sysctl_sched_features = - SCHED_FEAT_NEW_FAIR_SLEEPERS * 1 | - SCHED_FEAT_WAKEUP_PREEMPT * 1 | - SCHED_FEAT_START_DEBIT * 1 | - SCHED_FEAT_AFFINE_WAKEUPS * 1 | - SCHED_FEAT_CACHE_HOT_BUDDY * 1 | - SCHED_FEAT_SYNC_WAKEUPS * 1 | - SCHED_FEAT_HRTICK * 1 | - SCHED_FEAT_DOUBLE_TICK * 0 | - SCHED_FEAT_NORMALIZED_SLEEPER * 1 | - SCHED_FEAT_DEADLINE * 1; - -#define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x) +#include "sched_features.h" + 0; + +#undef SCHED_FEAT + +#ifdef CONFIG_SCHED_DEBUG +#define SCHED_FEAT(name, enabled) \ + #name , + +__read_mostly char *sched_feat_names[] = { +#include "sched_features.h" + NULL +}; + +#undef SCHED_FEAT + +int sched_feat_open(struct inode *inode, struct file *filp) +{ + filp->private_data = inode->i_private; + return 0; +} + +static ssize_t +sched_feat_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char *buf; + int r = 0; + int len = 0; + int i; + + for (i = 0; sched_feat_names[i]; i++) { + len += strlen(sched_feat_names[i]); + len += 4; + } + + buf = kmalloc(len + 2, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + for (i = 0; sched_feat_names[i]; i++) { + if (sysctl_sched_features & (1UL << i)) + r += sprintf(buf + r, "%s ", sched_feat_names[i]); + else + r += sprintf(buf + r, "no_%s ", sched_feat_names[i]); + } + + r += sprintf(buf + r, "\n"); + WARN_ON(r >= len + 2); + + r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); + + kfree(buf); + + return r; +} + +static ssize_t +sched_feat_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char buf[64]; + char *cmp = buf; + int neg = 0; + int i; + + if (cnt > 63) + cnt = 63; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + if (strncmp(buf, "no_", 3) == 0) { + neg = 1; + cmp += 3; + } + + for (i = 0; sched_feat_names[i]; i++) { + int len = strlen(sched_feat_names[i]); + + if (strncmp(cmp, sched_feat_names[i], len) == 0) { + if (neg) + sysctl_sched_features &= ~(1UL << i); + else + sysctl_sched_features |= (1UL << i); + break; + } + } + + if (!sched_feat_names[i]) + return -EINVAL; + + filp->f_pos += cnt; + + return cnt; +} + +static struct file_operations sched_feat_fops = { + .open = sched_feat_open, + .read = sched_feat_read, + .write = sched_feat_write, +}; + +static __init int sched_init_debug(void) +{ + int i, j, len; + + for (i = 0; sched_feat_names[i]; i++) { + len = strlen(sched_feat_names[i]); + + for (j = 0; j < len; j++) { + sched_feat_names[i][j] = + tolower(sched_feat_names[i][j]); + } + } + + debugfs_create_file("sched_features", 0644, NULL, NULL, + &sched_feat_fops); + + return 0; +} +late_initcall(sched_init_debug); + +#endif + +#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) /* * Number of tasks to iterate in a single balance run. diff --git a/kernel/sched_features.h b/kernel/sched_features.h new file mode 100644 index 0000000000..1c7283cb95 --- /dev/null +++ b/kernel/sched_features.h @@ -0,0 +1,10 @@ +SCHED_FEAT(NEW_FAIR_SLEEPERS, 1) +SCHED_FEAT(WAKEUP_PREEMPT, 1) +SCHED_FEAT(START_DEBIT, 1) +SCHED_FEAT(AFFINE_WAKEUPS, 1) +SCHED_FEAT(CACHE_HOT_BUDDY, 1) +SCHED_FEAT(SYNC_WAKEUPS, 1) +SCHED_FEAT(HRTICK, 1) +SCHED_FEAT(DOUBLE_TICK, 0) +SCHED_FEAT(NORMALIZED_SLEEPER, 1) +SCHED_FEAT(DEADLINE, 1) -- 2.39.5