[PATCH 2/4] event code fixes/cleanup

Dmitry Torokhov
2004-08-24T06:36:43Z

===================================================================

ChangeSet@1.1843, 2004-08-24 01:11:02-05:00, dtor_core-yWtbtysYrB+LZ21kGMrzwg@public.gmane.org
ACPI: Move event handling code from bus.c into event.c to cut down
amount of exported implementation details. Also:

- when closing /proc/acpi/event drop all events that have not
been read yet so next time it is opened userspace is not fed
old events;
- do not reimplement wait_event_interruptible, just use it;
- do not return -EIO if an event is 'stolen', 0 is proper return
code;
- tidy up read procedure (ensure that list is not empty before
fetching next event)

Signed-off-by: Dmitry Torokhov <dtor-JGs/UdohzUI@public.gmane.org>

drivers/acpi/Makefile | 4 -
drivers/acpi/ac.c | 4 -
drivers/acpi/acpi_ksyms.c | 9 +-
drivers/acpi/asus_acpi.c | 5 -
drivers/acpi/battery.c | 3
drivers/acpi/bus.c | 94 ----------------------------
drivers/acpi/button.c | 4 -
drivers/acpi/event.c | 152 ++++++++++++++++++++++++++++++++++------------
drivers/acpi/processor.c | 7 +-
drivers/acpi/thermal.c | 9 +-
include/acpi/acpi_bus.h | 16 ----
include/acpi/acpi_event.h | 47 ++++++++++++++
12 files changed, 190 insertions(+), 164 deletions(-)

===================================================================

diff -Nru a/drivers/acpi/Makefile b/drivers/acpi/Makefile
--- a/drivers/acpi/Makefile 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/Makefile 2004-08-24 01:16:54 -05:00
@@ -32,7 +32,7 @@
# ACPI Bus and Device Drivers
#
obj-$(CONFIG_ACPI_BUS) += sleep/
-obj-$(CONFIG_ACPI_BUS) += bus.o
+obj-$(CONFIG_ACPI_BUS) += bus.o event.o
obj-$(CONFIG_ACPI_AC) += ac.o
obj-$(CONFIG_ACPI_BATTERY) += battery.o
obj-$(CONFIG_ACPI_BUTTON) += button.o
@@ -42,7 +42,7 @@
obj-$(CONFIG_ACPI_POWER) += power.o
obj-$(CONFIG_ACPI_PROCESSOR) += processor.o
obj-$(CONFIG_ACPI_THERMAL) += thermal.o
-obj-$(CONFIG_ACPI_SYSTEM) += system.o event.o
+obj-$(CONFIG_ACPI_SYSTEM) += system.o
obj-$(CONFIG_ACPI_DEBUG) += debug.o
obj-$(CONFIG_ACPI_NUMA) += numa.o
obj-$(CONFIG_ACPI_ASUS) += asus_acpi.o
diff -Nru a/drivers/acpi/ac.c b/drivers/acpi/ac.c
--- a/drivers/acpi/ac.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/ac.c 2004-08-24 01:16:54 -05:00
@@ -29,7 +29,9 @@
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+
#include <acpi/acpi_bus.h>
+#include <acpi/acpi_event.h>
#include <acpi/acpi_drivers.h>

@@ -220,7 +222,7 @@
switch (event) {
case ACPI_AC_NOTIFY_STATUS:
acpi_ac_get_state(ac);
- acpi_bus_generate_event(device, event, (u32) ac->state);
+ acpi_generate_event(device, event, (u32) ac->state);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
diff -Nru a/drivers/acpi/acpi_ksyms.c b/drivers/acpi/acpi_ksyms.c
--- a/drivers/acpi/acpi_ksyms.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/acpi_ksyms.c 2004-08-24 01:16:54 -05:00
@@ -27,6 +27,7 @@
#include <linux/acpi.h>
#include <acpi/acpi.h>
#include <acpi/acpi_bus.h>
+#include <acpi/acpi_event.h>

#ifdef CONFIG_ACPI_INTERPRETER
@@ -120,10 +121,11 @@
#endif /*CONFIG_ACPI_INTERPRETER*/

-/* ACPI Bus Driver (acpi_bus.c) */
+/* ACPI Bus Driver */

#ifdef CONFIG_ACPI_BUS

+/* bus.c */
EXPORT_SYMBOL(acpi_fadt);
EXPORT_SYMBOL(acpi_walk_namespace);
EXPORT_SYMBOL(acpi_root_dir);
@@ -131,10 +133,11 @@
EXPORT_SYMBOL(acpi_bus_get_status);
EXPORT_SYMBOL(acpi_bus_get_power);
EXPORT_SYMBOL(acpi_bus_set_power);
-EXPORT_SYMBOL(acpi_bus_generate_event);
-EXPORT_SYMBOL(acpi_bus_receive_event);
EXPORT_SYMBOL(acpi_bus_register_driver);
EXPORT_SYMBOL(acpi_bus_unregister_driver);
+
+/* event.c */
+EXPORT_SYMBOL(acpi_generate_event);

#endif /*CONFIG_ACPI_BUS*/

diff -Nru a/drivers/acpi/asus_acpi.c b/drivers/acpi/asus_acpi.c
--- a/drivers/acpi/asus_acpi.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/asus_acpi.c 2004-08-24 01:16:54 -05:00
@@ -40,6 +40,7 @@
#include <linux/proc_fs.h>
#include <acpi/acpi_drivers.h>
#include <acpi/acpi_bus.h>
+#include <acpi/acpi_event.h>
#include <asm/uaccess.h>

#define ASUS_ACPI_VERSION "0.28"
@@ -949,8 +950,8 @@
hotk->brightness = (event & ~((u32) BR_DOWN));
}

- acpi_bus_generate_event(hotk->device, event,
- hotk->event_count[event % 128]++);
+ acpi_generate_event(hotk->device, event,
+ hotk->event_count[event % 128]++);

return;
}
diff -Nru a/drivers/acpi/battery.c b/drivers/acpi/battery.c
--- a/drivers/acpi/battery.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/battery.c 2004-08-24 01:16:54 -05:00
@@ -31,6 +31,7 @@
#include <asm/uaccess.h>

#include <acpi/acpi_bus.h>
+#include <acpi/acpi_event.h>
#include <acpi/acpi_drivers.h>

@@ -719,7 +720,7 @@
case ACPI_BATTERY_NOTIFY_STATUS:
case ACPI_BATTERY_NOTIFY_INFO:
acpi_battery_check(battery);
- acpi_bus_generate_event(device, event, battery->flags.present);
+ acpi_generate_event(device, event, battery->flags.present);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
diff -Nru a/drivers/acpi/bus.c b/drivers/acpi/bus.c
--- a/drivers/acpi/bus.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/bus.c 2004-08-24 01:16:54 -05:00
@@ -272,100 +272,6 @@
}

-
-/* --------------------------------------------------------------------------
- Event Management
- -------------------------------------------------------------------------- */
-
-static spinlock_t acpi_bus_event_lock = SPIN_LOCK_UNLOCKED;
-
-LIST_HEAD(acpi_bus_event_list);
-DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
-
-extern int event_is_open;
-
-int
-acpi_bus_generate_event (
- struct acpi_device *device,
- u8 type,
- int data)
-{
- struct acpi_bus_event *event = NULL;
- unsigned long flags = 0;
-
- ACPI_FUNCTION_TRACE("acpi_bus_generate_event");
-
- if (!device)
- return_VALUE(-EINVAL);
-
- /* drop event on the floor if no one's listening */
- if (!event_is_open)
- return_VALUE(0);
-
- event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
- if (!event)
- return_VALUE(-ENOMEM);
-
- strcpy(event->device_class, device->pnp.device_class);
- strcpy(event->bus_id, device->pnp.bus_id);
- event->type = type;
- event->data = data;
-
- spin_lock_irqsave(&acpi_bus_event_lock, flags);
- list_add_tail(&event->node, &acpi_bus_event_list);
- spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
-
- wake_up_interruptible(&acpi_bus_event_queue);
-
- return_VALUE(0);
-}
-
-int
-acpi_bus_receive_event (
- struct acpi_bus_event *event)
-{
- unsigned long flags = 0;
- struct acpi_bus_event *entry = NULL;
-
- DECLARE_WAITQUEUE(wait, current);
-
- ACPI_FUNCTION_TRACE("acpi_bus_receive_event");
-
- if (!event)
- return -EINVAL;
-
- if (list_empty(&acpi_bus_event_list)) {
-
- set_current_state(TASK_INTERRUPTIBLE);
- add_wait_queue(&acpi_bus_event_queue, &wait);
-
- if (list_empty(&acpi_bus_event_list))
- schedule();
-
- remove_wait_queue(&acpi_bus_event_queue, &wait);
- set_current_state(TASK_RUNNING);
-
- if (signal_pending(current))
- return_VALUE(-ERESTARTSYS);
- }
-
- spin_lock_irqsave(&acpi_bus_event_lock, flags);
- entry = list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
- if (entry)
- list_del(&entry->node);
- spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
-
- if (!entry)
- return_VALUE(-ENODEV);
-
- memcpy(event, entry, sizeof(struct acpi_bus_event));
-
- kfree(entry);
-
- return_VALUE(0);
-}
-
-
/* --------------------------------------------------------------------------
Notification Handling
-------------------------------------------------------------------------- */
diff -Nru a/drivers/acpi/button.c b/drivers/acpi/button.c
--- a/drivers/acpi/button.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/button.c 2004-08-24 01:16:54 -05:00
@@ -29,7 +29,9 @@
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+
#include <acpi/acpi_bus.h>
+#include <acpi/acpi_event.h>
#include <acpi/acpi_drivers.h>

@@ -290,7 +292,7 @@

switch (event) {
case ACPI_BUTTON_NOTIFY_STATUS:
- acpi_bus_generate_event(button->device, event, ++button->pushed);
+ acpi_generate_event(button->device, event, ++button->pushed);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
diff -Nru a/drivers/acpi/event.c b/drivers/acpi/event.c
--- a/drivers/acpi/event.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/event.c 2004-08-24 01:16:54 -05:00
@@ -10,73 +10,141 @@
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/poll.h>
+#include <acpi/acpi_event.h>
#include <acpi/acpi_drivers.h>

#define _COMPONENT ACPI_SYSTEM_COMPONENT
ACPI_MODULE_NAME ("event")

-/* Global vars for handling event proc entry */
-static spinlock_t acpi_system_event_lock = SPIN_LOCK_UNLOCKED;
-int event_is_open = 0;
-extern struct list_head acpi_bus_event_list;
-extern wait_queue_head_t acpi_bus_event_queue;
+DECLARE_WAIT_QUEUE_HEAD(acpi_event_queue);
+LIST_HEAD(acpi_event_list);
+static spinlock_t acpi_event_lock = SPIN_LOCK_UNLOCKED;
+static int event_is_open;
+
+int
+acpi_generate_event(
+ struct acpi_device *device,
+ u8 type,
+ int data)
+{
+ struct acpi_bus_event *event;
+ unsigned long flags;
+ int result = 0;
+
+ ACPI_FUNCTION_TRACE("acpi_generate_event");
+
+ if (!device)
+ return_VALUE(-EINVAL);
+
+ spin_lock_irqsave(&acpi_event_lock, flags);
+
+ /* drop event on the floor if no one's listening */
+ if (!event_is_open)
+ goto out;
+
+ event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
+ if (!event) {
+ result = -ENOMEM;
+ goto out;
+ }
+
+ strcpy(event->device_class, device->pnp.device_class);
+ strcpy(event->bus_id, device->pnp.bus_id);
+ event->type = type;
+ event->data = data;
+
+ list_add_tail(&event->node, &acpi_event_list);
+ wake_up_interruptible(&acpi_event_queue);
+
+out:
+ spin_unlock_irqrestore(&acpi_event_lock, flags);
+ return_VALUE(result);
+}
+
+static struct acpi_bus_event *acpi_fetch_event(void)
+{
+ struct acpi_bus_event *event = NULL;
+ unsigned long flags;
+
+ ACPI_FUNCTION_TRACE("acpi_fetch_event");
+
+ spin_lock_irqsave(&acpi_event_lock, flags);
+
+ if (!list_empty(&acpi_event_list)) {
+ event = list_entry(acpi_event_list.next,
+ struct acpi_bus_event, node);
+ list_del(&event->node);
+ }
+
+ spin_unlock_irqrestore(&acpi_event_lock, flags);
+
+ return_PTR(event);
+}

static int
acpi_system_open_event(struct inode *inode, struct file *file)
{
- spin_lock_irq (&acpi_system_event_lock);
+ int rc = 0;

- if(event_is_open)
- goto out_busy;
+ spin_lock_irq(&acpi_event_lock);
+
+ if (event_is_open) {
+ rc = -EBUSY;
+ goto out;
+ }

event_is_open = 1;

- spin_unlock_irq (&acpi_system_event_lock);
- return 0;
+out:
+ spin_unlock_irq(&acpi_event_lock);
+ return rc;
+}

-out_busy:
- spin_unlock_irq (&acpi_system_event_lock);
- return -EBUSY;
+static inline int
+event_to_string(struct acpi_bus_event *event, char *buffer)
+{
+ return sprintf(buffer, "%s %s %08x %08x\n",
+ event->device_class ? event->device_class : "<unknown>",
+ event->bus_id ? event->bus_id : "<unknown>",
+ event->type, event->data);
}

static ssize_t
-acpi_system_read_event (
+acpi_system_read_event(
struct file *file,
char __user *buffer,
size_t count,
loff_t *ppos)
{
- int result = 0;
- struct acpi_bus_event event;
+ int result;
+ struct acpi_bus_event *event;
static char str[ACPI_MAX_STRING];
- static int chars_remaining = 0;
+ static int chars_remaining;
static char *ptr;

ACPI_FUNCTION_TRACE("acpi_system_read_event");

if (!chars_remaining) {
- memset(&event, 0, sizeof(struct acpi_bus_event));
-
- if ((file->f_flags & O_NONBLOCK)
- && (list_empty(&acpi_bus_event_list)))
+ if (list_empty(&acpi_event_list) &&
+ (file->f_flags & O_NONBLOCK))
return_VALUE(-EAGAIN);

- result = acpi_bus_receive_event(&event);
- if (result) {
- return_VALUE(-EIO);
- }
-
- chars_remaining = sprintf(str, "%s %s %08x %08x\n",
- event.device_class?event.device_class:"<unknown>",
- event.bus_id?event.bus_id:"<unknown>",
- event.type, event.data);
+ result = wait_event_interruptible(acpi_event_queue,
+ !list_empty(&acpi_event_list));
+ if (result)
+ return_VALUE(result);
+
+ if ((event = acpi_fetch_event()) == NULL)
+ return_VALUE(0);
+
+ chars_remaining = event_to_string(event, str);
ptr = str;
+ kfree(event);
}

- if (chars_remaining < count) {
+ if (chars_remaining < count)
count = chars_remaining;
- }

if (copy_to_user(buffer, ptr, count))
return_VALUE(-EFAULT);
@@ -91,9 +159,19 @@
static int
acpi_system_close_event(struct inode *inode, struct file *file)
{
- spin_lock_irq (&acpi_system_event_lock);
+ struct acpi_bus_event *event, *next;
+
+ spin_lock_irq(&acpi_event_lock);
+
+ /* We won't be interested in old events, will we? */
+ list_for_each_entry_safe(event, next, &acpi_event_list, node) {
+ list_del(&event->node);
+ kfree(event);
+ }
+
event_is_open = 0;
- spin_unlock_irq (&acpi_system_event_lock);
+
+ spin_unlock_irq(&acpi_event_lock);
return 0;
}

@@ -102,8 +180,8 @@
struct file *file,
poll_table *wait)
{
- poll_wait(file, &acpi_bus_event_queue, wait);
- if (!list_empty(&acpi_bus_event_list))
+ poll_wait(file, &acpi_event_queue, wait);
+ if (!list_empty(&acpi_event_list))
return POLLIN | POLLRDNORM;
return 0;
}
@@ -130,7 +208,7 @@
if (entry)
entry->proc_fops = &acpi_system_event_ops;
else {
- ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+ ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Unable to create '%s' proc fs entry\n","event" ));
error = -EFAULT;
}
diff -Nru a/drivers/acpi/processor.c b/drivers/acpi/processor.c
--- a/drivers/acpi/processor.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/processor.c 2004-08-24 01:16:54 -05:00
@@ -50,6 +50,7 @@

#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
+#include <acpi/acpi_event.h>
#include <acpi/processor.h>

@@ -2312,12 +2313,12 @@
switch (event) {
case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
acpi_processor_ppc_has_changed(pr);
- acpi_bus_generate_event(device, event,
- pr->performance_platform_limit);
+ acpi_generate_event(device, event,
+ pr->performance_platform_limit);
break;
case ACPI_PROCESSOR_NOTIFY_POWER:
/* TBD */
- acpi_bus_generate_event(device, event, 0);
+ acpi_generate_event(device, event, 0);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
diff -Nru a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
--- a/drivers/acpi/thermal.c 2004-08-24 01:16:54 -05:00
+++ b/drivers/acpi/thermal.c 2004-08-24 01:16:54 -05:00
@@ -42,6 +42,7 @@
#include <asm/uaccess.h>

#include <acpi/acpi_bus.h>
+#include <acpi/acpi_event.h>
#include <acpi/acpi_drivers.h>

#define ACPI_THERMAL_COMPONENT 0x04000000
@@ -469,7 +470,7 @@
return_VALUE(result);

printk(KERN_EMERG "Critical temperature reached (%ld C), shutting down.\n", KELVIN_TO_CELSIUS(tz->temperature));
- acpi_bus_generate_event(device, ACPI_THERMAL_NOTIFY_CRITICAL, tz->trips.critical.flags.enabled);
+ acpi_generate_event(device, ACPI_THERMAL_NOTIFY_CRITICAL, tz->trips.critical.flags.enabled);

acpi_thermal_call_usermode(ACPI_THERMAL_PATH_POWEROFF);

@@ -500,7 +501,7 @@
if (result)
return_VALUE(result);

- acpi_bus_generate_event(device, ACPI_THERMAL_NOTIFY_HOT, tz->trips.hot.flags.enabled);
+ acpi_generate_event(device, ACPI_THERMAL_NOTIFY_HOT, tz->trips.hot.flags.enabled);

/* TBD: Call user-mode "sleep(S4)" function */

@@ -1199,12 +1200,12 @@
case ACPI_THERMAL_NOTIFY_THRESHOLDS:
acpi_thermal_get_trip_points(tz);
acpi_thermal_check(tz);
- acpi_bus_generate_event(device, event, 0);
+ acpi_generate_event(device, event, 0);
break;
case ACPI_THERMAL_NOTIFY_DEVICES:
if (tz->flags.devices)
acpi_thermal_get_devices(tz);
- acpi_bus_generate_event(device, event, 0);
+ acpi_generate_event(device, event, 0);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
diff -Nru a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
--- a/include/acpi/acpi_bus.h 2004-08-24 01:16:54 -05:00
+++ b/include/acpi/acpi_bus.h 2004-08-24 01:16:54 -05:00
@@ -293,20 +293,6 @@

#define acpi_driver_data(d) ((d)->driver_data)

-
-/*
- * Events
- * ------
- */
-
-struct acpi_bus_event {
- struct list_head node;
- acpi_device_class device_class;
- acpi_bus_id bus_id;
- u32 type;
- u32 data;
-};
-
extern struct subsystem acpi_subsys;

/*
@@ -317,8 +303,6 @@
int acpi_bus_get_status (struct acpi_device *device);
int acpi_bus_get_power (acpi_handle handle, int *state);
int acpi_bus_set_power (acpi_handle handle, int state);
-int acpi_bus_generate_event (struct acpi_device *device, u8 type, int data);
-int acpi_bus_receive_event (struct acpi_bus_event *event);
int acpi_bus_register_driver (struct acpi_driver *driver);
int acpi_bus_unregister_driver (struct acpi_driver *driver);

diff -Nru a/include/acpi/acpi_event.h b/include/acpi/acpi_event.h
--- /dev/null Wed Dec 31 16:00:00 196900
+++ b/include/acpi/acpi_event.h 2004-08-24 01:16:54 -05:00
@@ -0,0 +1,47 @@
+/*
+ * acpi_event.h - ACPI events to user space
+ *
+ * Copyright (C) 2001, 2002 Andy Grover <andrew.grover-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
+ * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#ifndef __ACPI_EVENT_H__
+#define __ACPI_EVENT_H__
+
+#include <linux/kobject.h>
+
+#include <acpi/acpi_bus.h>
+
+struct acpi_bus_event {
+ struct list_head node;
+ acpi_device_class device_class;
+ acpi_bus_id bus_id;
+ u32 type;
+ u32 data;
+};
+
+/*
+ * External Functions
+ */
+
+int acpi_generate_event(struct acpi_device *device, u8 type, int data);
+
+#endif /*__ACPI_EVENT_H__*/