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-rw-r--r--Documentation/ABI/testing/sysfs-firmware-memmap2
-rw-r--r--Documentation/PCI/PCIEBUS-HOWTO.txt2
-rw-r--r--Documentation/cgroups/cgroups.txt6
-rw-r--r--Documentation/cgroups/cpusets.txt65
-rw-r--r--Documentation/driver-model/device.txt8
-rw-r--r--Documentation/filesystems/sysfs.txt50
-rw-r--r--Documentation/hwmon/hpfall.c101
-rw-r--r--Documentation/hwmon/lis3lv02d8
-rw-r--r--Documentation/tracers/mmiotrace.txt6
9 files changed, 185 insertions, 63 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-memmap b/Documentation/ABI/testing/sysfs-firmware-memmap
index 0d99ee6ae02e..eca0d65087dc 100644
--- a/Documentation/ABI/testing/sysfs-firmware-memmap
+++ b/Documentation/ABI/testing/sysfs-firmware-memmap
@@ -1,6 +1,6 @@
What: /sys/firmware/memmap/
Date: June 2008
-Contact: Bernhard Walle <bwalle@suse.de>
+Contact: Bernhard Walle <bernhard.walle@gmx.de>
Description:
On all platforms, the firmware provides a memory map which the
kernel reads. The resources from that memory map are registered
diff --git a/Documentation/PCI/PCIEBUS-HOWTO.txt b/Documentation/PCI/PCIEBUS-HOWTO.txt
index 9a07e38631b0..6bd5f372adec 100644
--- a/Documentation/PCI/PCIEBUS-HOWTO.txt
+++ b/Documentation/PCI/PCIEBUS-HOWTO.txt
@@ -93,7 +93,7 @@ the PCI Express Port Bus driver from loading a service driver.
int pcie_port_service_register(struct pcie_port_service_driver *new)
-This API replaces the Linux Driver Model's pci_module_init API. A
+This API replaces the Linux Driver Model's pci_register_driver API. A
service driver should always calls pcie_port_service_register at
module init. Note that after service driver being loaded, calls
such as pci_enable_device(dev) and pci_set_master(dev) are no longer
diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt
index d9e5d6f41b92..93feb8444489 100644
--- a/Documentation/cgroups/cgroups.txt
+++ b/Documentation/cgroups/cgroups.txt
@@ -252,10 +252,8 @@ cgroup file system directories.
When a task is moved from one cgroup to another, it gets a new
css_set pointer - if there's an already existing css_set with the
desired collection of cgroups then that group is reused, else a new
-css_set is allocated. Note that the current implementation uses a
-linear search to locate an appropriate existing css_set, so isn't
-very efficient. A future version will use a hash table for better
-performance.
+css_set is allocated. The appropriate existing css_set is located by
+looking into a hash table.
To allow access from a cgroup to the css_sets (and hence tasks)
that comprise it, a set of cg_cgroup_link objects form a lattice;
diff --git a/Documentation/cgroups/cpusets.txt b/Documentation/cgroups/cpusets.txt
index 5c86c258c791..0611e9528c7c 100644
--- a/Documentation/cgroups/cpusets.txt
+++ b/Documentation/cgroups/cpusets.txt
@@ -142,7 +142,7 @@ into the rest of the kernel, none in performance critical paths:
- in fork and exit, to attach and detach a task from its cpuset.
- in sched_setaffinity, to mask the requested CPUs by what's
allowed in that tasks cpuset.
- - in sched.c migrate_all_tasks(), to keep migrating tasks within
+ - in sched.c migrate_live_tasks(), to keep migrating tasks within
the CPUs allowed by their cpuset, if possible.
- in the mbind and set_mempolicy system calls, to mask the requested
Memory Nodes by what's allowed in that tasks cpuset.
@@ -175,6 +175,10 @@ files describing that cpuset:
- mem_exclusive flag: is memory placement exclusive?
- mem_hardwall flag: is memory allocation hardwalled
- memory_pressure: measure of how much paging pressure in cpuset
+ - memory_spread_page flag: if set, spread page cache evenly on allowed nodes
+ - memory_spread_slab flag: if set, spread slab cache evenly on allowed nodes
+ - sched_load_balance flag: if set, load balance within CPUs on that cpuset
+ - sched_relax_domain_level: the searching range when migrating tasks
In addition, the root cpuset only has the following file:
- memory_pressure_enabled flag: compute memory_pressure?
@@ -252,7 +256,7 @@ is causing.
This is useful both on tightly managed systems running a wide mix of
submitted jobs, which may choose to terminate or re-prioritize jobs that
-are trying to use more memory than allowed on the nodes assigned them,
+are trying to use more memory than allowed on the nodes assigned to them,
and with tightly coupled, long running, massively parallel scientific
computing jobs that will dramatically fail to meet required performance
goals if they start to use more memory than allowed to them.
@@ -378,7 +382,7 @@ as cpusets and sched_setaffinity.
The algorithmic cost of load balancing and its impact on key shared
kernel data structures such as the task list increases more than
linearly with the number of CPUs being balanced. So the scheduler
-has support to partition the systems CPUs into a number of sched
+has support to partition the systems CPUs into a number of sched
domains such that it only load balances within each sched domain.
Each sched domain covers some subset of the CPUs in the system;
no two sched domains overlap; some CPUs might not be in any sched
@@ -485,17 +489,22 @@ of CPUs allowed to a cpuset having 'sched_load_balance' enabled.
The internal kernel cpuset to scheduler interface passes from the
cpuset code to the scheduler code a partition of the load balanced
CPUs in the system. This partition is a set of subsets (represented
-as an array of cpumask_t) of CPUs, pairwise disjoint, that cover all
-the CPUs that must be load balanced.
-
-Whenever the 'sched_load_balance' flag changes, or CPUs come or go
-from a cpuset with this flag enabled, or a cpuset with this flag
-enabled is removed, the cpuset code builds a new such partition and
-passes it to the scheduler sched domain setup code, to have the sched
-domains rebuilt as necessary.
+as an array of struct cpumask) of CPUs, pairwise disjoint, that cover
+all the CPUs that must be load balanced.
+
+The cpuset code builds a new such partition and passes it to the
+scheduler sched domain setup code, to have the sched domains rebuilt
+as necessary, whenever:
+ - the 'sched_load_balance' flag of a cpuset with non-empty CPUs changes,
+ - or CPUs come or go from a cpuset with this flag enabled,
+ - or 'sched_relax_domain_level' value of a cpuset with non-empty CPUs
+ and with this flag enabled changes,
+ - or a cpuset with non-empty CPUs and with this flag enabled is removed,
+ - or a cpu is offlined/onlined.
This partition exactly defines what sched domains the scheduler should
-setup - one sched domain for each element (cpumask_t) in the partition.
+setup - one sched domain for each element (struct cpumask) in the
+partition.
The scheduler remembers the currently active sched domain partitions.
When the scheduler routine partition_sched_domains() is invoked from
@@ -559,7 +568,7 @@ domain, the largest value among those is used. Be careful, if one
requests 0 and others are -1 then 0 is used.
Note that modifying this file will have both good and bad effects,
-and whether it is acceptable or not will be depend on your situation.
+and whether it is acceptable or not depends on your situation.
Don't modify this file if you are not sure.
If your situation is:
@@ -600,19 +609,15 @@ to allocate a page of memory for that task.
If a cpuset has its 'cpus' modified, then each task in that cpuset
will have its allowed CPU placement changed immediately. Similarly,
-if a tasks pid is written to a cpusets 'tasks' file, in either its
-current cpuset or another cpuset, then its allowed CPU placement is
-changed immediately. If such a task had been bound to some subset
-of its cpuset using the sched_setaffinity() call, the task will be
-allowed to run on any CPU allowed in its new cpuset, negating the
-affect of the prior sched_setaffinity() call.
+if a tasks pid is written to another cpusets 'tasks' file, then its
+allowed CPU placement is changed immediately. If such a task had been
+bound to some subset of its cpuset using the sched_setaffinity() call,
+the task will be allowed to run on any CPU allowed in its new cpuset,
+negating the effect of the prior sched_setaffinity() call.
In summary, the memory placement of a task whose cpuset is changed is
updated by the kernel, on the next allocation of a page for that task,
-but the processor placement is not updated, until that tasks pid is
-rewritten to the 'tasks' file of its cpuset. This is done to avoid
-impacting the scheduler code in the kernel with a check for changes
-in a tasks processor placement.
+and the processor placement is updated immediately.
Normally, once a page is allocated (given a physical page
of main memory) then that page stays on whatever node it
@@ -681,10 +686,14 @@ and then start a subshell 'sh' in that cpuset:
# The next line should display '/Charlie'
cat /proc/self/cpuset
-In the future, a C library interface to cpusets will likely be
-available. For now, the only way to query or modify cpusets is
-via the cpuset file system, using the various cd, mkdir, echo, cat,
-rmdir commands from the shell, or their equivalent from C.
+There are ways to query or modify cpusets:
+ - via the cpuset file system directly, using the various cd, mkdir, echo,
+ cat, rmdir commands from the shell, or their equivalent from C.
+ - via the C library libcpuset.
+ - via the C library libcgroup.
+ (http://sourceforge.net/proects/libcg/)
+ - via the python application cset.
+ (http://developer.novell.com/wiki/index.php/Cpuset)
The sched_setaffinity calls can also be done at the shell prompt using
SGI's runon or Robert Love's taskset. The mbind and set_mempolicy
@@ -756,7 +765,7 @@ mount -t cpuset X /dev/cpuset
is equivalent to
-mount -t cgroup -ocpuset X /dev/cpuset
+mount -t cgroup -ocpuset,noprefix X /dev/cpuset
echo "/sbin/cpuset_release_agent" > /dev/cpuset/release_agent
2.2 Adding/removing cpus
diff --git a/Documentation/driver-model/device.txt b/Documentation/driver-model/device.txt
index a05ec50f8004..a7cbfff40d07 100644
--- a/Documentation/driver-model/device.txt
+++ b/Documentation/driver-model/device.txt
@@ -127,9 +127,11 @@ void unlock_device(struct device * dev);
Attributes
~~~~~~~~~~
struct device_attribute {
- struct attribute attr;
- ssize_t (*show)(struct device * dev, char * buf, size_t count, loff_t off);
- ssize_t (*store)(struct device * dev, const char * buf, size_t count, loff_t off);
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
};
Attributes of devices can be exported via drivers using a simple
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt
index 9e9c348275a9..7e81e37c0b1e 100644
--- a/Documentation/filesystems/sysfs.txt
+++ b/Documentation/filesystems/sysfs.txt
@@ -2,8 +2,10 @@
sysfs - _The_ filesystem for exporting kernel objects.
Patrick Mochel <mochel@osdl.org>
+Mike Murphy <mamurph@cs.clemson.edu>
-10 January 2003
+Revised: 22 February 2009
+Original: 10 January 2003
What it is:
@@ -64,12 +66,13 @@ An attribute definition is simply:
struct attribute {
char * name;
+ struct module *owner;
mode_t mode;
};
-int sysfs_create_file(struct kobject * kobj, struct attribute * attr);
-void sysfs_remove_file(struct kobject * kobj, struct attribute * attr);
+int sysfs_create_file(struct kobject * kobj, const struct attribute * attr);
+void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr);
A bare attribute contains no means to read or write the value of the
@@ -80,9 +83,11 @@ a specific object type.
For example, the driver model defines struct device_attribute like:
struct device_attribute {
- struct attribute attr;
- ssize_t (*show)(struct device * dev, char * buf);
- ssize_t (*store)(struct device * dev, const char * buf);
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
};
int device_create_file(struct device *, struct device_attribute *);
@@ -90,12 +95,8 @@ void device_remove_file(struct device *, struct device_attribute *);
It also defines this helper for defining device attributes:
-#define DEVICE_ATTR(_name, _mode, _show, _store) \
-struct device_attribute dev_attr_##_name = { \
- .attr = {.name = __stringify(_name) , .mode = _mode }, \
- .show = _show, \
- .store = _store, \
-};
+#define DEVICE_ATTR(_name, _mode, _show, _store) \
+struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
For example, declaring
@@ -107,9 +108,9 @@ static struct device_attribute dev_attr_foo = {
.attr = {
.name = "foo",
.mode = S_IWUSR | S_IRUGO,
+ .show = show_foo,
+ .store = store_foo,
},
- .show = show_foo,
- .store = store_foo,
};
@@ -161,10 +162,12 @@ To read or write attributes, show() or store() methods must be
specified when declaring the attribute. The method types should be as
simple as those defined for device attributes:
- ssize_t (*show)(struct device * dev, char * buf);
- ssize_t (*store)(struct device * dev, const char * buf);
+ssize_t (*show)(struct device * dev, struct device_attribute * attr,
+ char * buf);
+ssize_t (*store)(struct device * dev, struct device_attribute * attr,
+ const char * buf);
-IOW, they should take only an object and a buffer as parameters.
+IOW, they should take only an object, an attribute, and a buffer as parameters.
sysfs allocates a buffer of size (PAGE_SIZE) and passes it to the
@@ -299,14 +302,16 @@ The following interface layers currently exist in sysfs:
Structure:
struct device_attribute {
- struct attribute attr;
- ssize_t (*show)(struct device * dev, char * buf);
- ssize_t (*store)(struct device * dev, const char * buf);
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
};
Declaring:
-DEVICE_ATTR(_name, _str, _mode, _show, _store);
+DEVICE_ATTR(_name, _mode, _show, _store);
Creation/Removal:
@@ -342,7 +347,8 @@ Structure:
struct driver_attribute {
struct attribute attr;
ssize_t (*show)(struct device_driver *, char * buf);
- ssize_t (*store)(struct device_driver *, const char * buf);
+ ssize_t (*store)(struct device_driver *, const char * buf,
+ size_t count);
};
Declaring:
diff --git a/Documentation/hwmon/hpfall.c b/Documentation/hwmon/hpfall.c
new file mode 100644
index 000000000000..bbea1ccfd46a
--- /dev/null
+++ b/Documentation/hwmon/hpfall.c
@@ -0,0 +1,101 @@
+/* Disk protection for HP machines.
+ *
+ * Copyright 2008 Eric Piel
+ * Copyright 2009 Pavel Machek <pavel@suse.cz>
+ *
+ * GPLv2.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <string.h>
+#include <stdint.h>
+#include <errno.h>
+#include <signal.h>
+
+void write_int(char *path, int i)
+{
+ char buf[1024];
+ int fd = open(path, O_RDWR);
+ if (fd < 0) {
+ perror("open");
+ exit(1);
+ }
+ sprintf(buf, "%d", i);
+ if (write(fd, buf, strlen(buf)) != strlen(buf)) {
+ perror("write");
+ exit(1);
+ }
+ close(fd);
+}
+
+void set_led(int on)
+{
+ write_int("/sys/class/leds/hp::hddprotect/brightness", on);
+}
+
+void protect(int seconds)
+{
+ write_int("/sys/block/sda/device/unload_heads", seconds*1000);
+}
+
+int on_ac(void)
+{
+// /sys/class/power_supply/AC0/online
+}
+
+int lid_open(void)
+{
+// /proc/acpi/button/lid/LID/state
+}
+
+void ignore_me(void)
+{
+ protect(0);
+ set_led(0);
+
+}
+
+int main(int argc, char* argv[])
+{
+ int fd, ret;
+
+ fd = open("/dev/freefall", O_RDONLY);
+ if (fd < 0) {
+ perror("open");
+ return EXIT_FAILURE;
+ }
+
+ signal(SIGALRM, ignore_me);
+
+ for (;;) {
+ unsigned char count;
+
+ ret = read(fd, &count, sizeof(count));
+ alarm(0);
+ if ((ret == -1) && (errno == EINTR)) {
+ /* Alarm expired, time to unpark the heads */
+ continue;
+ }
+
+ if (ret != sizeof(count)) {
+ perror("read");
+ break;
+ }
+
+ protect(21);
+ set_led(1);
+ if (1 || on_ac() || lid_open()) {
+ alarm(2);
+ } else {
+ alarm(20);
+ }
+ }
+
+ close(fd);
+ return EXIT_SUCCESS;
+}
diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d
index 0fcfc4a7ccdc..287f8c902656 100644
--- a/Documentation/hwmon/lis3lv02d
+++ b/Documentation/hwmon/lis3lv02d
@@ -33,6 +33,14 @@ rate - reports the sampling rate of the accelerometer device in HZ
This driver also provides an absolute input class device, allowing
the laptop to act as a pinball machine-esque joystick.
+Another feature of the driver is misc device called "freefall" that
+acts similar to /dev/rtc and reacts on free-fall interrupts received
+from the device. It supports blocking operations, poll/select and
+fasync operation modes. You must read 1 bytes from the device. The
+result is number of free-fall interrupts since the last successful
+read (or 255 if number of interrupts would not fit).
+
+
Axes orientation
----------------
diff --git a/Documentation/tracers/mmiotrace.txt b/Documentation/tracers/mmiotrace.txt
index cde23b4a12a1..5731c67abc55 100644
--- a/Documentation/tracers/mmiotrace.txt
+++ b/Documentation/tracers/mmiotrace.txt
@@ -78,12 +78,10 @@ to view your kernel log and look for "mmiotrace has lost events" warning. If
events were lost, the trace is incomplete. You should enlarge the buffers and
try again. Buffers are enlarged by first seeing how large the current buffers
are:
-$ cat /debug/tracing/trace_entries
+$ cat /debug/tracing/buffer_size_kb
gives you a number. Approximately double this number and write it back, for
instance:
-$ echo 0 > /debug/tracing/tracing_enabled
-$ echo 128000 > /debug/tracing/trace_entries
-$ echo 1 > /debug/tracing/tracing_enabled
+$ echo 128000 > /debug/tracing/buffer_size_kb
Then start again from the top.
If you are doing a trace for a driver project, e.g. Nouveau, you should also