ACPI, cpuidle: Clarify C-state description in sysfs
Add a new sysfs entry under cpuidle states. desc - can be used by driver to
communicate to userspace any specific information about the state.
This helps in identifying the exact hardware C-states behind the ACPI C-state
definition.
Idea is to export this through powertop, which will help to map the C-state
reported by powertop to actual hardware C-state.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 10b6717..8ca3557 100644
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -126,6 +126,8 @@
printk(KERN_DEBUG "Monitor-Mwait will be used to enter C-%d "
"state\n", cx->type);
}
+ snprintf(cx->desc, ACPI_CX_DESC_LEN, "ACPI FFH INTEL MWAIT 0x%x",
+ cx->address);
out:
set_cpus_allowed(current, saved_mask);
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 32003fd..baa389b9 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -945,11 +945,16 @@
* Otherwise, ignore this info and continue.
*/
cx.entry_method = ACPI_CSTATE_HALT;
+ snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
} else {
continue;
}
+ } else {
+ snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
+ cx.address);
}
+
obj = &(element->package.elements[2]);
if (obj->type != ACPI_TYPE_INTEGER)
continue;
@@ -1643,6 +1648,11 @@
return -EINVAL;
}
+ for (i = 0; i < CPUIDLE_STATE_MAX; i++) {
+ dev->states[i].name[0] = '\0';
+ dev->states[i].desc[0] = '\0';
+ }
+
for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
cx = &pr->power.states[i];
state = &dev->states[count];
@@ -1659,6 +1669,7 @@
cpuidle_set_statedata(state, cx);
snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
+ strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
state->exit_latency = cx->latency;
state->target_residency = cx->latency * latency_factor;
state->power_usage = cx->power;
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 60f71e6..d73663a 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -219,7 +219,8 @@
cpuidle_set_statedata(state, NULL);
- snprintf(state->name, CPUIDLE_NAME_LEN, "C0 (poll idle)");
+ snprintf(state->name, CPUIDLE_NAME_LEN, "C0");
+ snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
state->exit_latency = 0;
state->target_residency = 0;
state->power_usage = -1;
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
index 088ea74..69102ca 100644
--- a/drivers/cpuidle/sysfs.c
+++ b/drivers/cpuidle/sysfs.c
@@ -218,16 +218,23 @@
return sprintf(buf, "%u\n", state->_name);\
}
-static ssize_t show_state_name(struct cpuidle_state *state, char *buf)
-{
- return sprintf(buf, "%s\n", state->name);
+#define define_show_state_str_function(_name) \
+static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
+{ \
+ if (state->_name[0] == '\0')\
+ return sprintf(buf, "<null>\n");\
+ return sprintf(buf, "%s\n", state->_name);\
}
define_show_state_function(exit_latency)
define_show_state_function(power_usage)
define_show_state_function(usage)
define_show_state_function(time)
+define_show_state_str_function(name)
+define_show_state_str_function(desc)
+
define_one_state_ro(name, show_state_name);
+define_one_state_ro(desc, show_state_desc);
define_one_state_ro(latency, show_state_exit_latency);
define_one_state_ro(power, show_state_power_usage);
define_one_state_ro(usage, show_state_usage);
@@ -235,6 +242,7 @@
static struct attribute *cpuidle_state_default_attrs[] = {
&attr_name.attr,
+ &attr_desc.attr,
&attr_latency.attr,
&attr_power.attr,
&attr_usage.attr,
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index cdc8004..06480bc 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -32,9 +32,11 @@
#define DOMAIN_COORD_TYPE_SW_ANY 0xfd
#define DOMAIN_COORD_TYPE_HW_ALL 0xfe
-#define ACPI_CSTATE_SYSTEMIO (0)
-#define ACPI_CSTATE_FFH (1)
-#define ACPI_CSTATE_HALT (2)
+#define ACPI_CSTATE_SYSTEMIO 0
+#define ACPI_CSTATE_FFH 1
+#define ACPI_CSTATE_HALT 2
+
+#define ACPI_CX_DESC_LEN 32
/* Power Management */
@@ -74,6 +76,7 @@
u64 time;
struct acpi_processor_cx_policy promotion;
struct acpi_processor_cx_policy demotion;
+ char desc[ACPI_CX_DESC_LEN];
};
struct acpi_processor_power {
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index 385d45b..6b72a45 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -19,6 +19,7 @@
#define CPUIDLE_STATE_MAX 8
#define CPUIDLE_NAME_LEN 16
+#define CPUIDLE_DESC_LEN 32
struct cpuidle_device;
@@ -29,6 +30,7 @@
struct cpuidle_state {
char name[CPUIDLE_NAME_LEN];
+ char desc[CPUIDLE_DESC_LEN];
void *driver_data;
unsigned int flags;