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path: root/drivers/acpi/processor_throttling.c
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Diffstat (limited to 'drivers/acpi/processor_throttling.c')
-rw-r--r--drivers/acpi/processor_throttling.c190
1 files changed, 73 insertions, 117 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c
index ff3632717c5..fa84e974433 100644
--- a/drivers/acpi/processor_throttling.c
+++ b/drivers/acpi/processor_throttling.c
@@ -32,10 +32,6 @@
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/cpufreq.h>
-#ifdef CONFIG_ACPI_PROCFS
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#endif
#include <asm/io.h>
#include <asm/uaccess.h>
@@ -370,6 +366,58 @@ int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
}
/*
+ * This function is used to reevaluate whether the T-state is valid
+ * after one CPU is onlined/offlined.
+ * It is noted that it won't reevaluate the following properties for
+ * the T-state.
+ * 1. Control method.
+ * 2. the number of supported T-state
+ * 3. TSD domain
+ */
+void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
+ unsigned long action)
+{
+ int result = 0;
+
+ if (action == CPU_DEAD) {
+ /* When one CPU is offline, the T-state throttling
+ * will be invalidated.
+ */
+ pr->flags.throttling = 0;
+ return;
+ }
+ /* the following is to recheck whether the T-state is valid for
+ * the online CPU
+ */
+ if (!pr->throttling.state_count) {
+ /* If the number of T-state is invalid, it is
+ * invalidated.
+ */
+ pr->flags.throttling = 0;
+ return;
+ }
+ pr->flags.throttling = 1;
+
+ /* Disable throttling (if enabled). We'll let subsequent
+ * policy (e.g.thermal) decide to lower performance if it
+ * so chooses, but for now we'll crank up the speed.
+ */
+
+ result = acpi_processor_get_throttling(pr);
+ if (result)
+ goto end;
+
+ if (pr->throttling.state) {
+ result = acpi_processor_set_throttling(pr, 0, false);
+ if (result)
+ goto end;
+ }
+
+end:
+ if (result)
+ pr->flags.throttling = 0;
+}
+/*
* _PTC - Processor Throttling Control (and status) register location
*/
static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
@@ -876,7 +924,11 @@ static int acpi_processor_get_throttling(struct acpi_processor *pr)
*/
cpumask_copy(saved_mask, &current->cpus_allowed);
/* FIXME: use work_on_cpu() */
- set_cpus_allowed_ptr(current, cpumask_of(pr->id));
+ if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
+ /* Can't migrate to the target pr->id CPU. Exit */
+ free_cpumask_var(saved_mask);
+ return -ENODEV;
+ }
ret = pr->throttling.acpi_processor_get_throttling(pr);
/* restore the previous state */
set_cpus_allowed_ptr(current, saved_mask);
@@ -1051,6 +1103,14 @@ int acpi_processor_set_throttling(struct acpi_processor *pr,
return -ENOMEM;
}
+ if (cpu_is_offline(pr->id)) {
+ /*
+ * the cpu pointed by pr->id is offline. Unnecessary to change
+ * the throttling state any more.
+ */
+ return -ENODEV;
+ }
+
cpumask_copy(saved_mask, &current->cpus_allowed);
t_state.target_state = state;
p_throttling = &(pr->throttling);
@@ -1074,7 +1134,11 @@ int acpi_processor_set_throttling(struct acpi_processor *pr,
*/
if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
/* FIXME: use work_on_cpu() */
- set_cpus_allowed_ptr(current, cpumask_of(pr->id));
+ if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
+ /* Can't migrate to the pr->id CPU. Exit */
+ ret = -ENODEV;
+ goto exit;
+ }
ret = p_throttling->acpi_processor_set_throttling(pr,
t_state.target_state, force);
} else {
@@ -1106,7 +1170,8 @@ int acpi_processor_set_throttling(struct acpi_processor *pr,
}
t_state.cpu = i;
/* FIXME: use work_on_cpu() */
- set_cpus_allowed_ptr(current, cpumask_of(i));
+ if (set_cpus_allowed_ptr(current, cpumask_of(i)))
+ continue;
ret = match_pr->throttling.
acpi_processor_set_throttling(
match_pr, t_state.target_state, force);
@@ -1126,6 +1191,7 @@ int acpi_processor_set_throttling(struct acpi_processor *pr,
/* restore the previous state */
/* FIXME: use work_on_cpu() */
set_cpus_allowed_ptr(current, saved_mask);
+exit:
free_cpumask_var(online_throttling_cpus);
free_cpumask_var(saved_mask);
return ret;
@@ -1216,113 +1282,3 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr)
return result;
}
-#ifdef CONFIG_ACPI_PROCFS
-/* proc interface */
-static int acpi_processor_throttling_seq_show(struct seq_file *seq,
- void *offset)
-{
- struct acpi_processor *pr = seq->private;
- int i = 0;
- int result = 0;
-
- if (!pr)
- goto end;
-
- if (!(pr->throttling.state_count > 0)) {
- seq_puts(seq, "<not supported>\n");
- goto end;
- }
-
- result = acpi_processor_get_throttling(pr);
-
- if (result) {
- seq_puts(seq,
- "Could not determine current throttling state.\n");
- goto end;
- }
-
- seq_printf(seq, "state count: %d\n"
- "active state: T%d\n"
- "state available: T%d to T%d\n",
- pr->throttling.state_count, pr->throttling.state,
- pr->throttling_platform_limit,
- pr->throttling.state_count - 1);
-
- seq_puts(seq, "states:\n");
- if (pr->throttling.acpi_processor_get_throttling ==
- acpi_processor_get_throttling_fadt) {
- for (i = 0; i < pr->throttling.state_count; i++)
- seq_printf(seq, " %cT%d: %02d%%\n",
- (i == pr->throttling.state ? '*' : ' '), i,
- (pr->throttling.states[i].performance ? pr->
- throttling.states[i].performance / 10 : 0));
- } else {
- for (i = 0; i < pr->throttling.state_count; i++)
- seq_printf(seq, " %cT%d: %02d%%\n",
- (i == pr->throttling.state ? '*' : ' '), i,
- (int)pr->throttling.states_tss[i].
- freqpercentage);
- }
-
- end:
- return 0;
-}
-
-static int acpi_processor_throttling_open_fs(struct inode *inode,
- struct file *file)
-{
- return single_open(file, acpi_processor_throttling_seq_show,
- PDE(inode)->data);
-}
-
-static ssize_t acpi_processor_write_throttling(struct file *file,
- const char __user * buffer,
- size_t count, loff_t * data)
-{
- int result = 0;
- struct seq_file *m = file->private_data;
- struct acpi_processor *pr = m->private;
- char state_string[5] = "";
- char *charp = NULL;
- size_t state_val = 0;
- char tmpbuf[5] = "";
-
- if (!pr || (count > sizeof(state_string) - 1))
- return -EINVAL;
-
- if (copy_from_user(state_string, buffer, count))
- return -EFAULT;
-
- state_string[count] = '\0';
- if ((count > 0) && (state_string[count-1] == '\n'))
- state_string[count-1] = '\0';
-
- charp = state_string;
- if ((state_string[0] == 't') || (state_string[0] == 'T'))
- charp++;
-
- state_val = simple_strtoul(charp, NULL, 0);
- if (state_val >= pr->throttling.state_count)
- return -EINVAL;
-
- snprintf(tmpbuf, 5, "%zu", state_val);
-
- if (strcmp(tmpbuf, charp) != 0)
- return -EINVAL;
-
- result = acpi_processor_set_throttling(pr, state_val, false);
- if (result)
- return result;
-
- return count;
-}
-
-const struct file_operations acpi_processor_throttling_fops = {
- .owner = THIS_MODULE,
- .open = acpi_processor_throttling_open_fs,
- .read = seq_read,
- .write = acpi_processor_write_throttling,
- .llseek = seq_lseek,
- .release = single_release,
-};
-#endif