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-rw-r--r--kernel/cpuset.c84
1 files changed, 2 insertions, 82 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index e196510..0864f40 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -755,68 +755,13 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial)
}
/*
- * For a given cpuset cur, partition the system as follows
- * a. All cpus in the parent cpuset's cpus_allowed that are not part of any
- * exclusive child cpusets
- * b. All cpus in the current cpuset's cpus_allowed that are not part of any
- * exclusive child cpusets
- * Build these two partitions by calling partition_sched_domains
- *
- * Call with manage_mutex held. May nest a call to the
- * lock_cpu_hotplug()/unlock_cpu_hotplug() pair.
- * Must not be called holding callback_mutex, because we must
- * not call lock_cpu_hotplug() while holding callback_mutex.
- */
-
-static void update_cpu_domains(struct cpuset *cur)
-{
- struct cpuset *c, *par = cur->parent;
- cpumask_t pspan, cspan;
-
- if (par == NULL || cpus_empty(cur->cpus_allowed))
- return;
-
- /*
- * Get all cpus from parent's cpus_allowed not part of exclusive
- * children
- */
- pspan = par->cpus_allowed;
- list_for_each_entry(c, &par->children, sibling) {
- if (is_cpu_exclusive(c))
- cpus_andnot(pspan, pspan, c->cpus_allowed);
- }
- if (!is_cpu_exclusive(cur)) {
- cpus_or(pspan, pspan, cur->cpus_allowed);
- if (cpus_equal(pspan, cur->cpus_allowed))
- return;
- cspan = CPU_MASK_NONE;
- } else {
- if (cpus_empty(pspan))
- return;
- cspan = cur->cpus_allowed;
- /*
- * Get all cpus from current cpuset's cpus_allowed not part
- * of exclusive children
- */
- list_for_each_entry(c, &cur->children, sibling) {
- if (is_cpu_exclusive(c))
- cpus_andnot(cspan, cspan, c->cpus_allowed);
- }
- }
-
- lock_cpu_hotplug();
- partition_sched_domains(&pspan, &cspan);
- unlock_cpu_hotplug();
-}
-
-/*
* Call with manage_mutex held. May take callback_mutex during call.
*/
static int update_cpumask(struct cpuset *cs, char *buf)
{
struct cpuset trialcs;
- int retval, cpus_unchanged;
+ int retval;
/* top_cpuset.cpus_allowed tracks cpu_online_map; it's read-only */
if (cs == &top_cpuset)
@@ -843,12 +788,9 @@ static int update_cpumask(struct cpuset *cs, char *buf)
retval = validate_change(cs, &trialcs);
if (retval < 0)
return retval;
- cpus_unchanged = cpus_equal(cs->cpus_allowed, trialcs.cpus_allowed);
mutex_lock(&callback_mutex);
cs->cpus_allowed = trialcs.cpus_allowed;
mutex_unlock(&callback_mutex);
- if (is_cpu_exclusive(cs) && !cpus_unchanged)
- update_cpu_domains(cs);
return 0;
}
@@ -1085,7 +1027,7 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, char *buf)
{
int turning_on;
struct cpuset trialcs;
- int err, cpu_exclusive_changed;
+ int err;
turning_on = (simple_strtoul(buf, NULL, 10) != 0);
@@ -1098,14 +1040,10 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, char *buf)
err = validate_change(cs, &trialcs);
if (err < 0)
return err;
- cpu_exclusive_changed =
- (is_cpu_exclusive(cs) != is_cpu_exclusive(&trialcs));
mutex_lock(&callback_mutex);
cs->flags = trialcs.flags;
mutex_unlock(&callback_mutex);
- if (cpu_exclusive_changed)
- update_cpu_domains(cs);
return 0;
}
@@ -1965,17 +1903,6 @@ static int cpuset_mkdir(struct inode *dir, struct dentry *dentry, int mode)
return cpuset_create(c_parent, dentry->d_name.name, mode | S_IFDIR);
}
-/*
- * Locking note on the strange update_flag() call below:
- *
- * If the cpuset being removed is marked cpu_exclusive, then simulate
- * turning cpu_exclusive off, which will call update_cpu_domains().
- * The lock_cpu_hotplug() call in update_cpu_domains() must not be
- * made while holding callback_mutex. Elsewhere the kernel nests
- * callback_mutex inside lock_cpu_hotplug() calls. So the reverse
- * nesting would risk an ABBA deadlock.
- */
-
static int cpuset_rmdir(struct inode *unused_dir, struct dentry *dentry)
{
struct cpuset *cs = dentry->d_fsdata;
@@ -1995,13 +1922,6 @@ static int cpuset_rmdir(struct inode *unused_dir, struct dentry *dentry)
mutex_unlock(&manage_mutex);
return -EBUSY;
}
- if (is_cpu_exclusive(cs)) {
- int retval = update_flag(CS_CPU_EXCLUSIVE, cs, "0");
- if (retval < 0) {
- mutex_unlock(&manage_mutex);
- return retval;
- }
- }
parent = cs->parent;
mutex_lock(&callback_mutex);
set_bit(CS_REMOVED, &cs->flags);
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