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-rw-r--r--Documentation/DocBook/device-drivers.tmpl5
-rw-r--r--Documentation/DocBook/kernel-api.tmpl6
-rw-r--r--Documentation/feature-removal-schedule.txt10
-rw-r--r--Documentation/filesystems/nfs/00-INDEX4
-rw-r--r--Documentation/filesystems/nfs/idmapper.txt67
-rw-r--r--Documentation/filesystems/nfs/nfsroot.txt22
-rw-r--r--Documentation/filesystems/nfs/pnfs.txt48
-rw-r--r--Documentation/filesystems/proc.txt14
-rw-r--r--Documentation/hwmon/ltc426163
-rw-r--r--Documentation/kernel-parameters.txt5
-rw-r--r--Documentation/misc-devices/apds990x.txt111
-rw-r--r--Documentation/misc-devices/bh1770glc.txt116
-rw-r--r--Documentation/sysrq.txt7
-rw-r--r--Documentation/timers/hpet_example.c27
-rw-r--r--Documentation/trace/postprocess/trace-vmscan-postprocess.pl39
-rw-r--r--Documentation/vm/highmem.txt162
16 files changed, 686 insertions, 20 deletions
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index feca0758391e..22edcbb9ddaf 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -51,8 +51,13 @@
<sect1><title>Delaying, scheduling, and timer routines</title>
!Iinclude/linux/sched.h
!Ekernel/sched.c
+!Iinclude/linux/completion.h
!Ekernel/timer.c
</sect1>
+ <sect1><title>Wait queues and Wake events</title>
+!Iinclude/linux/wait.h
+!Ekernel/wait.c
+ </sect1>
<sect1><title>High-resolution timers</title>
!Iinclude/linux/ktime.h
!Iinclude/linux/hrtimer.h
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl
index 6b4e07f28b69..7160652a8736 100644
--- a/Documentation/DocBook/kernel-api.tmpl
+++ b/Documentation/DocBook/kernel-api.tmpl
@@ -93,6 +93,12 @@ X!Ilib/string.c
!Elib/crc32.c
!Elib/crc-ccitt.c
</sect1>
+
+ <sect1 id="idr"><title>idr/ida Functions</title>
+!Pinclude/linux/idr.h idr sync
+!Plib/idr.c IDA description
+!Elib/idr.c
+ </sect1>
</chapter>
<chapter id="mm">
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index e833c8c81e69..d2af87ba96e1 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -535,3 +535,13 @@ Why: Hareware scan is the prefer method for iwlwifi devices for
Who: Wey-Yi Guy <wey-yi.w.guy@intel.com>
----------------------------
+
+What: access to nfsd auth cache through sys_nfsservctl or '.' files
+ in the 'nfsd' filesystem.
+When: 2.6.40
+Why: This is a legacy interface which have been replaced by a more
+ dynamic cache. Continuing to maintain this interface is an
+ unnecessary burden.
+Who: NeilBrown <neilb@suse.de>
+
+----------------------------
diff --git a/Documentation/filesystems/nfs/00-INDEX b/Documentation/filesystems/nfs/00-INDEX
index 2f68cd688769..a57e12411d2a 100644
--- a/Documentation/filesystems/nfs/00-INDEX
+++ b/Documentation/filesystems/nfs/00-INDEX
@@ -12,5 +12,9 @@ nfs-rdma.txt
- how to install and setup the Linux NFS/RDMA client and server software
nfsroot.txt
- short guide on setting up a diskless box with NFS root filesystem.
+pnfs.txt
+ - short explanation of some of the internals of the pnfs client code
rpc-cache.txt
- introduction to the caching mechanisms in the sunrpc layer.
+idmapper.txt
+ - information for configuring request-keys to be used by idmapper
diff --git a/Documentation/filesystems/nfs/idmapper.txt b/Documentation/filesystems/nfs/idmapper.txt
new file mode 100644
index 000000000000..b9b4192ea8b5
--- /dev/null
+++ b/Documentation/filesystems/nfs/idmapper.txt
@@ -0,0 +1,67 @@
+
+=========
+ID Mapper
+=========
+Id mapper is used by NFS to translate user and group ids into names, and to
+translate user and group names into ids. Part of this translation involves
+performing an upcall to userspace to request the information. Id mapper will
+user request-key to perform this upcall and cache the result. The program
+/usr/sbin/nfs.idmap should be called by request-key, and will perform the
+translation and initialize a key with the resulting information.
+
+ NFS_USE_NEW_IDMAPPER must be selected when configuring the kernel to use this
+ feature.
+
+===========
+Configuring
+===========
+The file /etc/request-key.conf will need to be modified so /sbin/request-key can
+direct the upcall. The following line should be added:
+
+#OP TYPE DESCRIPTION CALLOUT INFO PROGRAM ARG1 ARG2 ARG3 ...
+#====== ======= =============== =============== ===============================
+create id_resolver * * /usr/sbin/nfs.idmap %k %d 600
+
+This will direct all id_resolver requests to the program /usr/sbin/nfs.idmap.
+The last parameter, 600, defines how many seconds into the future the key will
+expire. This parameter is optional for /usr/sbin/nfs.idmap. When the timeout
+is not specified, nfs.idmap will default to 600 seconds.
+
+id mapper uses for key descriptions:
+ uid: Find the UID for the given user
+ gid: Find the GID for the given group
+ user: Find the user name for the given UID
+ group: Find the group name for the given GID
+
+You can handle any of these individually, rather than using the generic upcall
+program. If you would like to use your own program for a uid lookup then you
+would edit your request-key.conf so it look similar to this:
+
+#OP TYPE DESCRIPTION CALLOUT INFO PROGRAM ARG1 ARG2 ARG3 ...
+#====== ======= =============== =============== ===============================
+create id_resolver uid:* * /some/other/program %k %d 600
+create id_resolver * * /usr/sbin/nfs.idmap %k %d 600
+
+Notice that the new line was added above the line for the generic program.
+request-key will find the first matching line and corresponding program. In
+this case, /some/other/program will handle all uid lookups and
+/usr/sbin/nfs.idmap will handle gid, user, and group lookups.
+
+See <file:Documentation/keys-request-keys.txt> for more information about the
+request-key function.
+
+
+=========
+nfs.idmap
+=========
+nfs.idmap is designed to be called by request-key, and should not be run "by
+hand". This program takes two arguments, a serialized key and a key
+description. The serialized key is first converted into a key_serial_t, and
+then passed as an argument to keyctl_instantiate (both are part of keyutils.h).
+
+The actual lookups are performed by functions found in nfsidmap.h. nfs.idmap
+determines the correct function to call by looking at the first part of the
+description string. For example, a uid lookup description will appear as
+"uid:user@domain".
+
+nfs.idmap will return 0 if the key was instantiated, and non-zero otherwise.
diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt
index f2430a7974e1..90c71c6f0d00 100644
--- a/Documentation/filesystems/nfs/nfsroot.txt
+++ b/Documentation/filesystems/nfs/nfsroot.txt
@@ -159,6 +159,28 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
Default: any
+nfsrootdebug
+
+ This parameter enables debugging messages to appear in the kernel
+ log at boot time so that administrators can verify that the correct
+ NFS mount options, server address, and root path are passed to the
+ NFS client.
+
+
+rdinit=<executable file>
+
+ To specify which file contains the program that starts system
+ initialization, administrators can use this command line parameter.
+ The default value of this parameter is "/init". If the specified
+ file exists and the kernel can execute it, root filesystem related
+ kernel command line parameters, including `nfsroot=', are ignored.
+
+ A description of the process of mounting the root file system can be
+ found in:
+
+ Documentation/early-userspace/README
+
+
3.) Boot Loader
diff --git a/Documentation/filesystems/nfs/pnfs.txt b/Documentation/filesystems/nfs/pnfs.txt
new file mode 100644
index 000000000000..bc0b9cfe095b
--- /dev/null
+++ b/Documentation/filesystems/nfs/pnfs.txt
@@ -0,0 +1,48 @@
+Reference counting in pnfs:
+==========================
+
+The are several inter-related caches. We have layouts which can
+reference multiple devices, each of which can reference multiple data servers.
+Each data server can be referenced by multiple devices. Each device
+can be referenced by multiple layouts. To keep all of this straight,
+we need to reference count.
+
+
+struct pnfs_layout_hdr
+----------------------
+The on-the-wire command LAYOUTGET corresponds to struct
+pnfs_layout_segment, usually referred to by the variable name lseg.
+Each nfs_inode may hold a pointer to a cache of of these layout
+segments in nfsi->layout, of type struct pnfs_layout_hdr.
+
+We reference the header for the inode pointing to it, across each
+outstanding RPC call that references it (LAYOUTGET, LAYOUTRETURN,
+LAYOUTCOMMIT), and for each lseg held within.
+
+Each header is also (when non-empty) put on a list associated with
+struct nfs_client (cl_layouts). Being put on this list does not bump
+the reference count, as the layout is kept around by the lseg that
+keeps it in the list.
+
+deviceid_cache
+--------------
+lsegs reference device ids, which are resolved per nfs_client and
+layout driver type. The device ids are held in a RCU cache (struct
+nfs4_deviceid_cache). The cache itself is referenced across each
+mount. The entries (struct nfs4_deviceid) themselves are held across
+the lifetime of each lseg referencing them.
+
+RCU is used because the deviceid is basically a write once, read many
+data structure. The hlist size of 32 buckets needs better
+justification, but seems reasonable given that we can have multiple
+deviceid's per filesystem, and multiple filesystems per nfs_client.
+
+The hash code is copied from the nfsd code base. A discussion of
+hashing and variations of this algorithm can be found at:
+http://groups.google.com/group/comp.lang.c/browse_thread/thread/9522965e2b8d3809
+
+data server cache
+-----------------
+file driver devices refer to data servers, which are kept in a module
+level cache. Its reference is held over the lifetime of the deviceid
+pointing to it.
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index a6aca8740883..a563b74c7aef 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -374,13 +374,13 @@ Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
-The first of these lines shows the same information as is displayed for the
-mapping in /proc/PID/maps. The remaining lines show the size of the mapping,
-the amount of the mapping that is currently resident in RAM, the "proportional
-set size” (divide each shared page by the number of processes sharing it), the
-number of clean and dirty shared pages in the mapping, and the number of clean
-and dirty private pages in the mapping. The "Referenced" indicates the amount
-of memory currently marked as referenced or accessed.
+The first of these lines shows the same information as is displayed for the
+mapping in /proc/PID/maps. The remaining lines show the size of the mapping
+(size), the amount of the mapping that is currently resident in RAM (RSS), the
+process' proportional share of this mapping (PSS), the number of clean and
+dirty shared pages in the mapping, and the number of clean and dirty private
+pages in the mapping. The "Referenced" indicates the amount of memory
+currently marked as referenced or accessed.
This file is only present if the CONFIG_MMU kernel configuration option is
enabled.
diff --git a/Documentation/hwmon/ltc4261 b/Documentation/hwmon/ltc4261
new file mode 100644
index 000000000000..eba2e2c4b94d
--- /dev/null
+++ b/Documentation/hwmon/ltc4261
@@ -0,0 +1,63 @@
+Kernel driver ltc4261
+=====================
+
+Supported chips:
+ * Linear Technology LTC4261
+ Prefix: 'ltc4261'
+ Addresses scanned: -
+ Datasheet:
+ http://cds.linear.com/docs/Datasheet/42612fb.pdf
+
+Author: Guenter Roeck <guenter.roeck@ericsson.com>
+
+
+Description
+-----------
+
+The LTC4261/LTC4261-2 negative voltage Hot Swap controllers allow a board
+to be safely inserted and removed from a live backplane.
+
+
+Usage Notes
+-----------
+
+This driver does not probe for LTC4261 devices, since there is no register
+which can be safely used to identify the chip. You will have to instantiate
+the devices explicitly.
+
+Example: the following will load the driver for an LTC4261 at address 0x10
+on I2C bus #1:
+$ modprobe ltc4261
+$ echo ltc4261 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
+
+
+Sysfs entries
+-------------
+
+Voltage readings provided by this driver are reported as obtained from the ADC
+registers. If a set of voltage divider resistors is installed, calculate the
+real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
+value of the divider resistor against the measured voltage and R2 is the value
+of the divider resistor against Ground.
+
+Current reading provided by this driver is reported as obtained from the ADC
+Current Sense register. The reported value assumes that a 1 mOhm sense resistor
+is installed. If a different sense resistor is installed, calculate the real
+current by dividing the reported value by the sense resistor value in mOhm.
+
+The chip has two voltage sensors, but only one set of voltage alarm status bits.
+In many many designs, those alarms are associated with the ADIN2 sensor, due to
+the proximity of the ADIN2 pin to the OV pin. ADIN2 is, however, not available
+on all chip variants. To ensure that the alarm condition is reported to the user,
+report it with both voltage sensors.
+
+in1_input ADIN2 voltage (mV)
+in1_min_alarm ADIN/ADIN2 Undervoltage alarm
+in1_max_alarm ADIN/ADIN2 Overvoltage alarm
+
+in2_input ADIN voltage (mV)
+in2_min_alarm ADIN/ADIN2 Undervoltage alarm
+in2_max_alarm ADIN/ADIN2 Overvoltage alarm
+
+curr1_input SENSE current (mA)
+curr1_alarm SENSE overcurrent alarm
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index b660085dcc69..4bc2f3c3da5b 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1541,12 +1541,15 @@ and is between 256 and 4096 characters. It is defined in the file
1 to enable accounting
Default value is 0.
- nfsaddrs= [NFS]
+ nfsaddrs= [NFS] Deprecated. Use ip= instead.
See Documentation/filesystems/nfs/nfsroot.txt.
nfsroot= [NFS] nfs root filesystem for disk-less boxes.
See Documentation/filesystems/nfs/nfsroot.txt.
+ nfsrootdebug [NFS] enable nfsroot debugging messages.
+ See Documentation/filesystems/nfs/nfsroot.txt.
+
nfs.callback_tcpport=
[NFS] set the TCP port on which the NFSv4 callback
channel should listen.
diff --git a/Documentation/misc-devices/apds990x.txt b/Documentation/misc-devices/apds990x.txt
new file mode 100644
index 000000000000..d5408cade32f
--- /dev/null
+++ b/Documentation/misc-devices/apds990x.txt
@@ -0,0 +1,111 @@
+Kernel driver apds990x
+======================
+
+Supported chips:
+Avago APDS990X
+
+Data sheet:
+Not freely available
+
+Author:
+Samu Onkalo <samu.p.onkalo@nokia.com>
+
+Description
+-----------
+
+APDS990x is a combined ambient light and proximity sensor. ALS and proximity
+functionality are highly connected. ALS measurement path must be running
+while the proximity functionality is enabled.
+
+ALS produces raw measurement values for two channels: Clear channel
+(infrared + visible light) and IR only. However, threshold comparisons happen
+using clear channel only. Lux value and the threshold level on the HW
+might vary quite much depending the spectrum of the light source.
+
+Driver makes necessary conversions to both directions so that user handles
+only lux values. Lux value is calculated using information from the both
+channels. HW threshold level is calculated from the given lux value to match
+with current type of the lightning. Sometimes inaccuracy of the estimations
+lead to false interrupt, but that doesn't harm.
+
+ALS contains 4 different gain steps. Driver automatically
+selects suitable gain step. After each measurement, reliability of the results
+is estimated and new measurement is trigged if necessary.
+
+Platform data can provide tuned values to the conversion formulas if
+values are known. Otherwise plain sensor default values are used.
+
+Proximity side is little bit simpler. There is no need for complex conversions.
+It produces directly usable values.
+
+Driver controls chip operational state using pm_runtime framework.
+Voltage regulators are controlled based on chip operational state.
+
+SYSFS
+-----
+
+
+chip_id
+ RO - shows detected chip type and version
+
+power_state
+ RW - enable / disable chip. Uses counting logic
+ 1 enables the chip
+ 0 disables the chip
+lux0_input
+ RO - measured lux value
+ sysfs_notify called when threshold interrupt occurs
+
+lux0_sensor_range
+ RO - lux0_input max value. Actually never reaches since sensor tends
+ to saturate much before that. Real max value varies depending
+ on the light spectrum etc.
+
+lux0_rate
+ RW - measurement rate in Hz
+
+lux0_rate_avail
+ RO - supported measurement rates
+
+lux0_calibscale
+ RW - calibration value. Set to neutral value by default.
+ Output results are multiplied with calibscale / calibscale_default
+ value.
+
+lux0_calibscale_default
+ RO - neutral calibration value
+
+lux0_thresh_above_value
+ RW - HI level threshold value. All results above the value
+ trigs an interrupt. 65535 (i.e. sensor_range) disables the above
+ interrupt.
+
+lux0_thresh_below_value
+ RW - LO level threshold value. All results below the value
+ trigs an interrupt. 0 disables the below interrupt.
+
+prox0_raw
+ RO - measured proximity value
+ sysfs_notify called when threshold interrupt occurs
+
+prox0_sensor_range
+ RO - prox0_raw max value (1023)
+
+prox0_raw_en
+ RW - enable / disable proximity - uses counting logic
+ 1 enables the proximity
+ 0 disables the proximity
+
+prox0_reporting_mode
+ RW - trigger / periodic. In "trigger" mode the driver tells two possible
+ values: 0 or prox0_sensor_range value. 0 means no proximity,
+ 1023 means proximity. This causes minimal number of interrupts.
+ In "periodic" mode the driver reports all values above
+ prox0_thresh_above. This causes more interrupts, but it can give
+ _rough_ estimate about the distance.
+
+prox0_reporting_mode_avail
+ RO - accepted values to prox0_reporting_mode (trigger, periodic)
+
+prox0_thresh_above_value
+ RW - threshold level which trigs proximity events.
diff --git a/Documentation/misc-devices/bh1770glc.txt b/Documentation/misc-devices/bh1770glc.txt
new file mode 100644
index 000000000000..7d64c014dc70
--- /dev/null
+++ b/Documentation/misc-devices/bh1770glc.txt
@@ -0,0 +1,116 @@
+Kernel driver bh1770glc
+=======================
+
+Supported chips:
+ROHM BH1770GLC
+OSRAM SFH7770
+
+Data sheet:
+Not freely available
+
+Author:
+Samu Onkalo <samu.p.onkalo@nokia.com>
+
+Description
+-----------
+BH1770GLC and SFH7770 are combined ambient light and proximity sensors.
+ALS and proximity parts operates on their own, but they shares common I2C
+interface and interrupt logic. In principle they can run on their own,
+but ALS side results are used to estimate reliability of the proximity sensor.
+
+ALS produces 16 bit lux values. The chip contains interrupt logic to produce
+low and high threshold interrupts.
+
+Proximity part contains IR-led driver up to 3 IR leds. The chip measures
+amount of reflected IR light and produces proximity result. Resolution is
+8 bit. Driver supports only one channel. Driver uses ALS results to estimate
+reliability of the proximity results. Thus ALS is always running while
+proximity detection is needed.
+
+Driver uses threshold interrupts to avoid need for polling the values.
+Proximity low interrupt doesn't exists in the chip. This is simulated
+by using a delayed work. As long as there is proximity threshold above
+interrupts the delayed work is pushed forward. So, when proximity level goes
+below the threshold value, there is no interrupt and the delayed work will
+finally run. This is handled as no proximity indication.
+
+Chip state is controlled via runtime pm framework when enabled in config.
+
+Calibscale factor is used to hide differences between the chips. By default
+value set to neutral state meaning factor of 1.00. To get proper values,
+calibrated source of light is needed as a reference. Calibscale factor is set
+so that measurement produces about the expected lux value.
+
+SYSFS
+-----
+
+chip_id
+ RO - shows detected chip type and version
+
+power_state
+ RW - enable / disable chip. Uses counting logic
+ 1 enables the chip
+ 0 disables the chip
+
+lux0_input
+ RO - measured lux value
+ sysfs_notify called when threshold interrupt occurs
+
+lux0_sensor_range
+ RO - lux0_input max value
+
+lux0_rate
+ RW - measurement rate in Hz
+
+lux0_rate_avail
+ RO - supported measurement rates
+
+lux0_thresh_above_value
+ RW - HI level threshold value. All results above the value
+ trigs an interrupt. 65535 (i.e. sensor_range) disables the above
+ interrupt.
+
+lux0_thresh_below_value
+ RW - LO level threshold value. All results below the value
+ trigs an interrupt. 0 disables the below interrupt.
+
+lux0_calibscale
+ RW - calibration value. Set to neutral value by default.
+ Output results are multiplied with calibscale / calibscale_default
+ value.
+
+lux0_calibscale_default
+ RO - neutral calibration value
+
+prox0_raw
+ RO - measured proximity value
+ sysfs_notify called when threshold interrupt occurs
+
+prox0_sensor_range
+ RO - prox0_raw max value
+
+prox0_raw_en
+ RW - enable / disable proximity - uses counting logic
+ 1 enables the proximity
+ 0 disables the proximity
+
+prox0_thresh_above_count
+ RW - number of proximity interrupts needed before triggering the event
+
+prox0_rate_above
+ RW - Measurement rate (in Hz) when the level is above threshold
+ i.e. when proximity on has been reported.
+
+prox0_rate_below
+ RW - Measurement rate (in Hz) when the level is below threshold
+ i.e. when proximity off has been reported.
+
+prox0_rate_avail
+ RO - Supported proximity measurement rates in Hz
+
+prox0_thresh_above0_value
+ RW - threshold level which trigs proximity events.
+ Filtered by persistence filter (prox0_thresh_above_count)
+
+prox0_thresh_above1_value
+ RW - threshold level which trigs event immediately
diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt
index 5c17196c8fe9..312e3754e8c5 100644
--- a/Documentation/sysrq.txt
+++ b/Documentation/sysrq.txt
@@ -75,7 +75,7 @@ On all - write a character to /proc/sysrq-trigger. e.g.:
'f' - Will call oom_kill to kill a memory hog process.
-'g' - Used by kgdb on ppc and sh platforms.
+'g' - Used by kgdb (kernel debugger)
'h' - Will display help (actually any other key than those listed
here will display help. but 'h' is easy to remember :-)
@@ -110,12 +110,15 @@ On all - write a character to /proc/sysrq-trigger. e.g.:
'u' - Will attempt to remount all mounted filesystems read-only.
-'v' - Dumps Voyager SMP processor info to your console.
+'v' - Forcefully restores framebuffer console
+'v' - Causes ETM buffer dump [ARM-specific]
'w' - Dumps tasks that are in uninterruptable (blocked) state.
'x' - Used by xmon interface on ppc/powerpc platforms.
+'y' - Show global CPU Registers [SPARC-64 specific]
+
'z' - Dump the ftrace buffer
'0'-'9' - Sets the console log level, controlling which kernel messages
diff --git a/Documentation/timers/hpet_example.c b/Documentation/timers/hpet_example.c
index 4bfafb7bc4c5..9a3e7012c190 100644
--- a/Documentation/timers/hpet_example.c
+++ b/Documentation/timers/hpet_example.c
@@ -97,6 +97,33 @@ hpet_open_close(int argc, const char **argv)
void
hpet_info(int argc, const char **argv)
{
+ struct hpet_info info;
+ int fd;
+
+ if (argc != 1) {
+ fprintf(stderr, "hpet_info: device-name\n");
+ return;
+ }
+
+ fd = open(argv[0], O_RDONLY);
+ if (fd < 0) {
+ fprintf(stderr, "hpet_info: open of %s failed\n", argv[0]);
+ return;
+ }
+
+ if (ioctl(fd, HPET_INFO, &info) < 0) {
+ fprintf(stderr, "hpet_info: failed to get info\n");
+ goto out;
+ }
+
+ fprintf(stderr, "hpet_info: hi_irqfreq 0x%lx hi_flags 0x%lx ",
+ info.hi_ireqfreq, info.hi_flags);
+ fprintf(stderr, "hi_hpet %d hi_timer %d\n",
+ info.hi_hpet, info.hi_timer);
+
+out:
+ close(fd);
+ return;
}
void
diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
index 1b55146d1c8d..b3e73ddb1567 100644
--- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
+++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
@@ -46,7 +46,7 @@ use constant HIGH_KSWAPD_LATENCY => 20;
use constant HIGH_KSWAPD_REWAKEUP => 21;
use constant HIGH_NR_SCANNED => 22;
use constant HIGH_NR_TAKEN => 23;
-use constant HIGH_NR_RECLAIM => 24;
+use constant HIGH_NR_RECLAIMED => 24;
use constant HIGH_NR_CONTIG_DIRTY => 25;
my %perprocesspid;
@@ -58,11 +58,13 @@ my $opt_read_procstat;
my $total_wakeup_kswapd;
my ($total_direct_reclaim, $total_direct_nr_scanned);
my ($total_direct_latency, $total_kswapd_latency);
+my ($total_direct_nr_reclaimed);
my ($total_direct_writepage_file_sync, $total_direct_writepage_file_async);
my ($total_direct_writepage_anon_sync, $total_direct_writepage_anon_async);
my ($total_kswapd_nr_scanned, $total_kswapd_wake);
my ($total_kswapd_writepage_file_sync, $total_kswapd_writepage_file_async);
my ($total_kswapd_writepage_anon_sync, $total_kswapd_writepage_anon_async);
+my ($total_kswapd_nr_reclaimed);
# Catch sigint and exit on request
my $sigint_report = 0;
@@ -104,7 +106,7 @@ my $regex_kswapd_wake_default = 'nid=([0-9]*) order=([0-9]*)';
my $regex_kswapd_sleep_default = 'nid=([0-9]*)';
my $regex_wakeup_kswapd_default = 'nid=([0-9]*) zid=([0-9]*) order=([0-9]*)';
my $regex_lru_isolate_default = 'isolate_mode=([0-9]*) order=([0-9]*) nr_requested=([0-9]*) nr_scanned=([0-9]*) nr_taken=([0-9]*) contig_taken=([0-9]*) contig_dirty=([0-9]*) contig_failed=([0-9]*)';
-my $regex_lru_shrink_inactive_default = 'lru=([A-Z_]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) priority=([0-9]*)';
+my $regex_lru_shrink_inactive_default = 'nid=([0-9]*) zid=([0-9]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) priority=([0-9]*) flags=([A-Z_|]*)';
my $regex_lru_shrink_active_default = 'lru=([A-Z_]*) nr_scanned=([0-9]*) nr_rotated=([0-9]*) priority=([0-9]*)';
my $regex_writepage_default = 'page=([0-9a-f]*) pfn=([0-9]*) flags=([A-Z_|]*)';
@@ -203,8 +205,8 @@ $regex_lru_shrink_inactive = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_shrink_inactive",
$regex_lru_shrink_inactive_default,
"nid", "zid",
- "lru",
- "nr_scanned", "nr_reclaimed", "priority");
+ "nr_scanned", "nr_reclaimed", "priority",
+ "flags");
$regex_lru_shrink_active = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_shrink_active",
$regex_lru_shrink_active_default,
@@ -375,6 +377,16 @@ EVENT_PROCESS:
my $nr_contig_dirty = $7;
$perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned;
$perprocesspid{$process_pid}->{HIGH_NR_CONTIG_DIRTY} += $nr_contig_dirty;
+ } elsif ($tracepoint eq "mm_vmscan_lru_shrink_inactive") {
+ $details = $5;
+ if ($details !~ /$regex_lru_shrink_inactive/o) {
+ print "WARNING: Failed to parse mm_vmscan_lru_shrink_inactive as expected\n";
+ print " $details\n";
+ print " $regex_lru_shrink_inactive/o\n";
+ next;
+ }
+ my $nr_reclaimed = $4;
+ $perprocesspid{$process_pid}->{HIGH_NR_RECLAIMED} += $nr_reclaimed;
} elsif ($tracepoint eq "mm_vmscan_writepage") {
$details = $5;
if ($details !~ /$regex_writepage/o) {
@@ -464,8 +476,8 @@ sub dump_stats {
# Print out process activity
printf("\n");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s\n", "Process", "Direct", "Wokeup", "Pages", "Pages", "Pages", "Time");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s\n", "details", "Rclms", "Kswapd", "Scanned", "Sync-IO", "ASync-IO", "Stalled");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s\n", "Process", "Direct", "Wokeup", "Pages", "Pages", "Pages", "Pages", "Time");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s\n", "details", "Rclms", "Kswapd", "Scanned", "Rclmed", "Sync-IO", "ASync-IO", "Stalled");
foreach $process_pid (keys %stats) {
if (!$stats{$process_pid}->{MM_VMSCAN_DIRECT_RECLAIM_BEGIN}) {
@@ -475,6 +487,7 @@ sub dump_stats {
$total_direct_reclaim += $stats{$process_pid}->{MM_VMSCAN_DIRECT_RECLAIM_BEGIN};
$total_wakeup_kswapd += $stats{$process_pid}->{MM_VMSCAN_WAKEUP_KSWAPD};
$total_direct_nr_scanned += $stats{$process_pid}->{HIGH_NR_SCANNED};
+ $total_direct_nr_reclaimed += $stats{$process_pid}->{HIGH_NR_RECLAIMED};
$total_direct_writepage_file_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC};
$total_direct_writepage_anon_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC};
$total_direct_writepage_file_async += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC};
@@ -489,11 +502,12 @@ sub dump_stats {
$index++;
}
- printf("%-" . $max_strlen . "s %8d %10d %8u %8u %8u %8.3f",
+ printf("%-" . $max_strlen . "s %8d %10d %8u %8u %8u %8u %8.3f",
$process_pid,
$stats{$process_pid}->{MM_VMSCAN_DIRECT_RECLAIM_BEGIN},
$stats{$process_pid}->{MM_VMSCAN_WAKEUP_KSWAPD},
$stats{$process_pid}->{HIGH_NR_SCANNED},
+ $stats{$process_pid}->{HIGH_NR_RECLAIMED},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_ASYNC},
$this_reclaim_delay / 1000);
@@ -529,8 +543,8 @@ sub dump_stats {
# Print out kswapd activity
printf("\n");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Kswapd", "Kswapd", "Order", "Pages", "Pages", "Pages");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Instance", "Wakeups", "Re-wakeup", "Scanned", "Sync-IO", "ASync-IO");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Kswapd", "Kswapd", "Order", "Pages", "Pages", "Pages", "Pages");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Instance", "Wakeups", "Re-wakeup", "Scanned", "Rclmed", "Sync-IO", "ASync-IO");
foreach $process_pid (keys %stats) {
if (!$stats{$process_pid}->{MM_VMSCAN_KSWAPD_WAKE}) {
@@ -539,16 +553,18 @@ sub dump_stats {
$total_kswapd_wake += $stats{$process_pid}->{MM_VMSCAN_KSWAPD_WAKE};
$total_kswapd_nr_scanned += $stats{$process_pid}->{HIGH_NR_SCANNED};
+ $total_kswapd_nr_reclaimed += $stats{$process_pid}->{HIGH_NR_RECLAIMED};
$total_kswapd_writepage_file_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC};
$total_kswapd_writepage_anon_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC};
$total_kswapd_writepage_file_async += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC};
$total_kswapd_writepage_anon_async += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_ASYNC};
- printf("%-" . $max_strlen . "s %8d %10d %8u %8i %8u",
+ printf("%-" . $max_strlen . "s %8d %10d %8u %8u %8i %8u",
$process_pid,
$stats{$process_pid}->{MM_VMSCAN_KSWAPD_WAKE},
$stats{$process_pid}->{HIGH_KSWAPD_REWAKEUP},
$stats{$process_pid}->{HIGH_NR_SCANNED},
+ $stats{$process_pid}->{HIGH_NR_RECLAIMED},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_ASYNC});
@@ -579,6 +595,7 @@ sub dump_stats {
print "\nSummary\n";
print "Direct reclaims: $total_direct_reclaim\n";
print "Direct reclaim pages scanned: $total_direct_nr_scanned\n";
+ print "Direct reclaim pages reclaimed: $total_direct_nr_reclaimed\n";
print "Direct reclaim write file sync I/O: $total_direct_writepage_file_sync\n";
print "Direct reclaim write anon sync I/O: $total_direct_writepage_anon_sync\n";
print "Direct reclaim write file async I/O: $total_direct_writepage_file_async\n";
@@ -588,6 +605,7 @@ sub dump_stats {
print "\n";
print "Kswapd wakeups: $total_kswapd_wake\n";
print "Kswapd pages scanned: $total_kswapd_nr_scanned\n";
+ print "Kswapd pages reclaimed: $total_kswapd_nr_reclaimed\n";
print "Kswapd reclaim write file sync I/O: $total_kswapd_writepage_file_sync\n";
print "Kswapd reclaim write anon sync I/O: $total_kswapd_writepage_anon_sync\n";
print "Kswapd reclaim write file async I/O: $total_kswapd_writepage_file_async\n";
@@ -612,6 +630,7 @@ sub aggregate_perprocesspid() {
$perprocess{$process}->{MM_VMSCAN_WAKEUP_KSWAPD} += $perprocesspid{$process_pid}->{MM_VMSCAN_WAKEUP_KSWAPD};
$perprocess{$process}->{HIGH_KSWAPD_REWAKEUP} += $perprocesspid{$process_pid}->{HIGH_KSWAPD_REWAKEUP};
$perprocess{$process}->{HIGH_NR_SCANNED} += $perprocesspid{$process_pid}->{HIGH_NR_SCANNED};
+ $perprocess{$process}->{HIGH_NR_RECLAIMED} += $perprocesspid{$process_pid}->{HIGH_NR_RECLAIMED};
$perprocess{$process}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC} += $perprocesspid{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC};
$perprocess{$process}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC} += $perprocesspid{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC};
$perprocess{$process}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC} += $perprocesspid{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC};
diff --git a/Documentation/vm/highmem.txt b/Documentation/vm/highmem.txt
new file mode 100644
index 000000000000..4324d24ffacd
--- /dev/null
+++ b/Documentation/vm/highmem.txt
@@ -0,0 +1,162 @@
+
+ ====================
+ HIGH MEMORY HANDLING
+ ====================
+
+By: Peter Zijlstra <a.p.zijlstra@chello.nl>
+
+Contents:
+
+ (*) What is high memory?
+
+ (*) Temporary virtual mappings.
+
+ (*) Using kmap_atomic.
+
+ (*) Cost of temporary mappings.
+
+ (*) i386 PAE.
+
+
+====================
+WHAT IS HIGH MEMORY?
+====================
+
+High memory (highmem) is used when the size of physical memory approaches or
+exceeds the maximum size of virtual memory. At that point it becomes
+impossible for the kernel to keep all of the available physical memory mapped
+at all times. This means the kernel needs to start using temporary mappings of
+the pieces of physical memory that it wants to access.
+
+The part of (physical) memory not covered by a permanent mapping is what we
+refer to as 'highmem'. There are various architecture dependent constraints on
+where exactly that border lies.
+
+In the i386 arch, for example, we choose to map the kernel into every process's
+VM space so that we don't have to pay the full TLB invalidation costs for
+kernel entry/exit. This means the available virtual memory space (4GiB on
+i386) has to be divided between user and kernel space.
+
+The traditional split for architectures using this approach is 3:1, 3GiB for
+userspace and the top 1GiB for kernel space:
+
+ +--------+ 0xffffffff
+ | Kernel |
+ +--------+ 0xc0000000
+ | |
+ | User |
+ | |
+ +--------+ 0x00000000
+
+This means that the kernel can at most map 1GiB of physical memory at any one
+time, but because we need virtual address space for other things - including
+temporary maps to access the rest of the physical memory - the actual direct
+map will typically be less (usually around ~896MiB).
+
+Other architectures that have mm context tagged TLBs can have separate kernel
+and user maps. Some hardware (like some ARMs), however, have limited virtual
+space when they use mm context tags.
+
+
+==========================
+TEMPORARY VIRTUAL MAPPINGS
+==========================
+
+The kernel contains several ways of creating temporary mappings:
+
+ (*) vmap(). This can be used to make a long duration mapping of multiple
+ physical pages into a contiguous virtual space. It needs global
+ synchronization to unmap.
+
+ (*) kmap(). This permits a short duration mapping of a single page. It needs
+ global synchronization, but is amortized somewhat. It is also prone to
+ deadlocks when using in a nested fashion, and so it is not recommended for
+ new code.
+
+ (*) kmap_atomic(). This permits a very short duration mapping of a single
+ page. Since the mapping is restricted to the CPU that issued it, it
+ performs well, but the issuing task is therefore required to stay on that
+ CPU until it has finished, lest some other task displace its mappings.
+
+ kmap_atomic() may also be used by interrupt contexts, since it is does not
+ sleep and the caller may not sleep until after kunmap_atomic() is called.
+
+ It may be assumed that k[un]map_atomic() won't fail.
+
+
+=================
+USING KMAP_ATOMIC
+=================
+
+When and where to use kmap_atomic() is straightforward. It is used when code
+wants to access the contents of a page that might be allocated from high memory
+(see __GFP_HIGHMEM), for example a page in the pagecache. The API has two
+functions, and they can be used in a manner similar to the following:
+
+ /* Find the page of interest. */
+ struct page *page = find_get_page(mapping, offset);
+
+ /* Gain access to the contents of that page. */
+ void *vaddr = kmap_atomic(page);
+
+ /* Do something to the contents of that page. */
+ memset(vaddr, 0, PAGE_SIZE);
+
+ /* Unmap that page. */
+ kunmap_atomic(vaddr);
+
+Note that the kunmap_atomic() call takes the result of the kmap_atomic() call
+not the argument.
+
+If you need to map two pages because you want to copy from one page to
+another you need to keep the kmap_atomic calls strictly nested, like:
+
+ vaddr1 = kmap_atomic(page1);
+ vaddr2 = kmap_atomic(page2);
+
+ memcpy(vaddr1, vaddr2, PAGE_SIZE);
+
+ kunmap_atomic(vaddr2);
+ kunmap_atomic(vaddr1);
+
+
+==========================
+COST OF TEMPORARY MAPPINGS
+==========================
+
+The cost of creating temporary mappings can be quite high. The arch has to
+manipulate the kernel's page tables, the data TLB and/or the MMU's registers.
+
+If CONFIG_HIGHMEM is not set, then the kernel will try and create a mapping
+simply with a bit of arithmetic that will convert the page struct address into
+a pointer to the page contents rather than juggling mappings about. In such a
+case, the unmap operation may be a null operation.
+
+If CONFIG_MMU is not set, then there can be no temporary mappings and no
+highmem. In such a case, the arithmetic approach will also be used.
+
+
+========
+i386 PAE
+========
+
+The i386 arch, under some circumstances, will permit you to stick up to 64GiB
+of RAM into your 32-bit machine. This has a number of consequences:
+
+ (*) Linux needs a page-frame structure for each page in the system and the
+ pageframes need to live in the permanent mapping, which means:
+
+ (*) you can have 896M/sizeof(struct page) page-frames at most; with struct
+ page being 32-bytes that would end up being something in the order of 112G
+ worth of pages; the kernel, however, needs to store more than just
+ page-frames in that memory...
+
+ (*) PAE makes your page tables larger - which slows the system down as more
+ data has to be accessed to traverse in TLB fills and the like. One
+ advantage is that PAE has more PTE bits and can provide advanced features
+ like NX and PAT.
+
+The general recommendation is that you don't use more than 8GiB on a 32-bit
+machine - although more might work for you and your workload, you're pretty
+much on your own - don't expect kernel developers to really care much if things
+come apart.
generated by cgit v1.2.3 (git 2.39.0) at 2025-01-21 03:57:53 +0300