提交 c309b917 编写于 作者: R Rusty Russell

cpumask: convert kernel/profile.c

Impact: Reduce kernel memory usage, use new cpumask API.

Avoid a static cpumask_t for prof_cpu_mask, and an on-stack cpumask_t
in prof_cpu_mask_write_proc.  Both become cpumask_var_t.

prof_cpu_mask is only allocated when profiling is on, but the NULL
checks are optimized out by gcc for the !CPUMASK_OFFSTACK case.

Also removed some strange and unnecessary casts.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
上级 bd232f97
...@@ -45,7 +45,7 @@ static unsigned long prof_len, prof_shift; ...@@ -45,7 +45,7 @@ static unsigned long prof_len, prof_shift;
int prof_on __read_mostly; int prof_on __read_mostly;
EXPORT_SYMBOL_GPL(prof_on); EXPORT_SYMBOL_GPL(prof_on);
static cpumask_t prof_cpu_mask = CPU_MASK_ALL; static cpumask_var_t prof_cpu_mask;
#ifdef CONFIG_SMP #ifdef CONFIG_SMP
static DEFINE_PER_CPU(struct profile_hit *[2], cpu_profile_hits); static DEFINE_PER_CPU(struct profile_hit *[2], cpu_profile_hits);
static DEFINE_PER_CPU(int, cpu_profile_flip); static DEFINE_PER_CPU(int, cpu_profile_flip);
...@@ -113,9 +113,13 @@ int __ref profile_init(void) ...@@ -113,9 +113,13 @@ int __ref profile_init(void)
buffer_bytes = prof_len*sizeof(atomic_t); buffer_bytes = prof_len*sizeof(atomic_t);
if (!slab_is_available()) { if (!slab_is_available()) {
prof_buffer = alloc_bootmem(buffer_bytes); prof_buffer = alloc_bootmem(buffer_bytes);
alloc_bootmem_cpumask_var(&prof_cpu_mask);
return 0; return 0;
} }
if (!alloc_cpumask_var(&prof_cpu_mask, GFP_KERNEL))
return -ENOMEM;
prof_buffer = kzalloc(buffer_bytes, GFP_KERNEL); prof_buffer = kzalloc(buffer_bytes, GFP_KERNEL);
if (prof_buffer) if (prof_buffer)
return 0; return 0;
...@@ -128,6 +132,7 @@ int __ref profile_init(void) ...@@ -128,6 +132,7 @@ int __ref profile_init(void)
if (prof_buffer) if (prof_buffer)
return 0; return 0;
free_cpumask_var(prof_cpu_mask);
return -ENOMEM; return -ENOMEM;
} }
...@@ -386,13 +391,15 @@ static int __cpuinit profile_cpu_callback(struct notifier_block *info, ...@@ -386,13 +391,15 @@ static int __cpuinit profile_cpu_callback(struct notifier_block *info,
return NOTIFY_BAD; return NOTIFY_BAD;
case CPU_ONLINE: case CPU_ONLINE:
case CPU_ONLINE_FROZEN: case CPU_ONLINE_FROZEN:
cpu_set(cpu, prof_cpu_mask); if (prof_cpu_mask != NULL)
cpumask_set_cpu(cpu, prof_cpu_mask);
break; break;
case CPU_UP_CANCELED: case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN: case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD: case CPU_DEAD:
case CPU_DEAD_FROZEN: case CPU_DEAD_FROZEN:
cpu_clear(cpu, prof_cpu_mask); if (prof_cpu_mask != NULL)
cpumask_clear_cpu(cpu, prof_cpu_mask);
if (per_cpu(cpu_profile_hits, cpu)[0]) { if (per_cpu(cpu_profile_hits, cpu)[0]) {
page = virt_to_page(per_cpu(cpu_profile_hits, cpu)[0]); page = virt_to_page(per_cpu(cpu_profile_hits, cpu)[0]);
per_cpu(cpu_profile_hits, cpu)[0] = NULL; per_cpu(cpu_profile_hits, cpu)[0] = NULL;
...@@ -430,7 +437,8 @@ void profile_tick(int type) ...@@ -430,7 +437,8 @@ void profile_tick(int type)
if (type == CPU_PROFILING && timer_hook) if (type == CPU_PROFILING && timer_hook)
timer_hook(regs); timer_hook(regs);
if (!user_mode(regs) && cpu_isset(smp_processor_id(), prof_cpu_mask)) if (!user_mode(regs) && prof_cpu_mask != NULL &&
cpumask_test_cpu(smp_processor_id(), prof_cpu_mask))
profile_hit(type, (void *)profile_pc(regs)); profile_hit(type, (void *)profile_pc(regs));
} }
...@@ -442,7 +450,7 @@ void profile_tick(int type) ...@@ -442,7 +450,7 @@ void profile_tick(int type)
static int prof_cpu_mask_read_proc(char *page, char **start, off_t off, static int prof_cpu_mask_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data) int count, int *eof, void *data)
{ {
int len = cpumask_scnprintf(page, count, (cpumask_t *)data); int len = cpumask_scnprintf(page, count, data);
if (count - len < 2) if (count - len < 2)
return -EINVAL; return -EINVAL;
len += sprintf(page + len, "\n"); len += sprintf(page + len, "\n");
...@@ -452,16 +460,20 @@ static int prof_cpu_mask_read_proc(char *page, char **start, off_t off, ...@@ -452,16 +460,20 @@ static int prof_cpu_mask_read_proc(char *page, char **start, off_t off,
static int prof_cpu_mask_write_proc(struct file *file, static int prof_cpu_mask_write_proc(struct file *file,
const char __user *buffer, unsigned long count, void *data) const char __user *buffer, unsigned long count, void *data)
{ {
cpumask_t *mask = (cpumask_t *)data; struct cpumask *mask = data;
unsigned long full_count = count, err; unsigned long full_count = count, err;
cpumask_t new_value; cpumask_var_t new_value;
err = cpumask_parse_user(buffer, count, &new_value); if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
if (err) return -ENOMEM;
return err;
*mask = new_value; err = cpumask_parse_user(buffer, count, new_value);
return full_count; if (!err) {
cpumask_copy(mask, new_value);
err = full_count;
}
free_cpumask_var(new_value);
return err;
} }
void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir) void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir)
...@@ -472,7 +484,7 @@ void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir) ...@@ -472,7 +484,7 @@ void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir)
entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir); entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir);
if (!entry) if (!entry)
return; return;
entry->data = (void *)&prof_cpu_mask; entry->data = prof_cpu_mask;
entry->read_proc = prof_cpu_mask_read_proc; entry->read_proc = prof_cpu_mask_read_proc;
entry->write_proc = prof_cpu_mask_write_proc; entry->write_proc = prof_cpu_mask_write_proc;
} }
......
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