diff options
Diffstat (limited to 'kernel/cpuset.c')
-rw-r--r-- | kernel/cpuset.c | 84 |
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); |