From 24b7099af71232b7568acd74770e6eb8f174f5d6 Mon Sep 17 00:00:00 2001 From: Carlos Chinea Date: Fri, 13 Apr 2012 15:55:13 +0300 Subject: HSI: Add HSI ABI documentation Adds sysfs HSI framework documentation Signed-off-by: Carlos Chinea Acked-by: Greg Kroah-Hartman Acked-by: Linus Walleij --- Documentation/ABI/testing/sysfs-bus-hsi | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-hsi (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-bus-hsi b/Documentation/ABI/testing/sysfs-bus-hsi new file mode 100644 index 000000000000..1b1b282a99e1 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-hsi @@ -0,0 +1,19 @@ +What: /sys/bus/hsi +Date: April 2012 +KernelVersion: 3.4 +Contact: Carlos Chinea +Description: + High Speed Synchronous Serial Interface (HSI) is a + serial interface mainly used for connecting application + engines (APE) with cellular modem engines (CMT) in cellular + handsets. + The bus will be populated with devices (hsi_clients) representing + the protocols available in the system. Bus drivers implement + those protocols. + +What: /sys/bus/hsi/devices/.../modalias +Date: April 2012 +KernelVersion: 3.4 +Contact: Carlos Chinea +Description: Stores the same MODALIAS value emitted by uevent + Format: hsi: -- cgit v1.2.3 From ddb6706af3cd372194cecd2cc61950519df620d7 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Tue, 24 Apr 2012 01:11:09 -0300 Subject: ASoC: dt: sgtl5000.txt: Add description for 'reg' field Add description for 'reg' field. Signed-off-by: Fabio Estevam Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/sound/sgtl5000.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/sound/sgtl5000.txt b/Documentation/devicetree/bindings/sound/sgtl5000.txt index 2c3cd413f042..9cc44449508d 100644 --- a/Documentation/devicetree/bindings/sound/sgtl5000.txt +++ b/Documentation/devicetree/bindings/sound/sgtl5000.txt @@ -3,6 +3,8 @@ Required properties: - compatible : "fsl,sgtl5000". +- reg : the I2C address of the device + Example: codec: sgtl5000@0a { -- cgit v1.2.3 From a05a4830a32ef9f89e7bd372a7bae9b96b1ac266 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 25 Apr 2012 12:46:50 -0400 Subject: keys: update the documentation with info about "logon" keys Acked-by: David Howells Signed-off-by: Jeff Layton --- Documentation/security/keys.txt | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt index 787717091421..d389acd31e19 100644 --- a/Documentation/security/keys.txt +++ b/Documentation/security/keys.txt @@ -123,7 +123,7 @@ KEY SERVICE OVERVIEW The key service provides a number of features besides keys: - (*) The key service defines two special key types: + (*) The key service defines three special key types: (+) "keyring" @@ -137,6 +137,18 @@ The key service provides a number of features besides keys: blobs of data. These can be created, updated and read by userspace, and aren't intended for use by kernel services. + (+) "logon" + + Like a "user" key, a "logon" key has a payload that is an arbitrary + blob of data. It is intended as a place to store secrets which are + accessible to the kernel but not to userspace programs. + + The description can be arbitrary, but must be prefixed with a non-zero + length string that describes the key "subclass". The subclass is + separated from the rest of the description by a ':'. "logon" keys can + be created and updated from userspace, but the payload is only + readable from kernel space. + (*) Each process subscribes to three keyrings: a thread-specific keyring, a process-specific keyring, and a session-specific keyring. -- cgit v1.2.3 From 26e0f90fded422f309deb6169dfbccb204435698 Mon Sep 17 00:00:00 2001 From: Marcos Paulo de Souza Date: Sun, 29 Apr 2012 22:29:30 +0200 Subject: PM / Freezer / Docs: Update documentation about freezing of tasks The file Documentation/power/freezing-of-tasks.txt was still referencing the TIF_FREEZE flag, that was removed by the commit d88e4cb67197d007fb778d62fe17360e970d5bfa(freezer: remove now unused TIF_FREEZE). This patch removes all the references of TIF_FREEZE that were left behind. Signed-off-by: Marcos Paulo de Souza Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- Documentation/power/freezing-of-tasks.txt | 37 ++++++++++++++++--------------- 1 file changed, 19 insertions(+), 18 deletions(-) (limited to 'Documentation') diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt index ec715cd78fbb..6ec291ea1c78 100644 --- a/Documentation/power/freezing-of-tasks.txt +++ b/Documentation/power/freezing-of-tasks.txt @@ -9,7 +9,7 @@ architectures). II. How does it work? -There are four per-task flags used for that, PF_NOFREEZE, PF_FROZEN, TIF_FREEZE +There are three per-task flags used for that, PF_NOFREEZE, PF_FROZEN and PF_FREEZER_SKIP (the last one is auxiliary). The tasks that have PF_NOFREEZE unset (all user space processes and some kernel threads) are regarded as 'freezable' and treated in a special way before the system enters a @@ -17,30 +17,31 @@ suspend state as well as before a hibernation image is created (in what follows we only consider hibernation, but the description also applies to suspend). Namely, as the first step of the hibernation procedure the function -freeze_processes() (defined in kernel/power/process.c) is called. It executes -try_to_freeze_tasks() that sets TIF_FREEZE for all of the freezable tasks and -either wakes them up, if they are kernel threads, or sends fake signals to them, -if they are user space processes. A task that has TIF_FREEZE set, should react -to it by calling the function called __refrigerator() (defined in -kernel/freezer.c), which sets the task's PF_FROZEN flag, changes its state -to TASK_UNINTERRUPTIBLE and makes it loop until PF_FROZEN is cleared for it. -Then, we say that the task is 'frozen' and therefore the set of functions -handling this mechanism is referred to as 'the freezer' (these functions are -defined in kernel/power/process.c, kernel/freezer.c & include/linux/freezer.h). -User space processes are generally frozen before kernel threads. +freeze_processes() (defined in kernel/power/process.c) is called. A system-wide +variable system_freezing_cnt (as opposed to a per-task flag) is used to indicate +whether the system is to undergo a freezing operation. And freeze_processes() +sets this variable. After this, it executes try_to_freeze_tasks() that sends a +fake signal to all user space processes, and wakes up all the kernel threads. +All freezable tasks must react to that by calling try_to_freeze(), which +results in a call to __refrigerator() (defined in kernel/freezer.c), which sets +the task's PF_FROZEN flag, changes its state to TASK_UNINTERRUPTIBLE and makes +it loop until PF_FROZEN is cleared for it. Then, we say that the task is +'frozen' and therefore the set of functions handling this mechanism is referred +to as 'the freezer' (these functions are defined in kernel/power/process.c, +kernel/freezer.c & include/linux/freezer.h). User space processes are generally +frozen before kernel threads. __refrigerator() must not be called directly. Instead, use the try_to_freeze() function (defined in include/linux/freezer.h), that checks -the task's TIF_FREEZE flag and makes the task enter __refrigerator() if the -flag is set. +if the task is to be frozen and makes the task enter __refrigerator(). For user space processes try_to_freeze() is called automatically from the signal-handling code, but the freezable kernel threads need to call it explicitly in suitable places or use the wait_event_freezable() or wait_event_freezable_timeout() macros (defined in include/linux/freezer.h) -that combine interruptible sleep with checking if TIF_FREEZE is set and calling -try_to_freeze(). The main loop of a freezable kernel thread may look like the -following one: +that combine interruptible sleep with checking if the task is to be frozen and +calling try_to_freeze(). The main loop of a freezable kernel thread may look +like the following one: set_freezable(); do { @@ -53,7 +54,7 @@ following one: (from drivers/usb/core/hub.c::hub_thread()). If a freezable kernel thread fails to call try_to_freeze() after the freezer has -set TIF_FREEZE for it, the freezing of tasks will fail and the entire +initiated a freezing operation, the freezing of tasks will fail and the entire hibernation operation will be cancelled. For this reason, freezable kernel threads must call try_to_freeze() somewhere or use one of the wait_event_freezable() and wait_event_freezable_timeout() macros. -- cgit v1.2.3 From b49960a05e32121d29316cfdf653894b88ac9190 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 2 May 2012 02:28:41 +0000 Subject: tcp: change tcp_adv_win_scale and tcp_rmem[2] tcp_adv_win_scale default value is 2, meaning we expect a good citizen skb to have skb->len / skb->truesize ratio of 75% (3/4) In 2.6 kernels we (mis)accounted for typical MSS=1460 frame : 1536 + 64 + 256 = 1856 'estimated truesize', and 1856 * 3/4 = 1392. So these skbs were considered as not bloated. With recent truesize fixes, a typical MSS=1460 frame truesize is now the more precise : 2048 + 256 = 2304. But 2304 * 3/4 = 1728. So these skb are not good citizen anymore, because 1460 < 1728 (GRO can escape this problem because it build skbs with a too low truesize.) This also means tcp advertises a too optimistic window for a given allocated rcvspace : When receiving frames, sk_rmem_alloc can hit sk_rcvbuf limit and we call tcp_prune_queue()/tcp_collapse() too often, especially when application is slow to drain its receive queue or in case of losses (netperf is fast, scp is slow). This is a major latency source. We should adjust the len/truesize ratio to 50% instead of 75% This patch : 1) changes tcp_adv_win_scale default to 1 instead of 2 2) increase tcp_rmem[2] limit from 4MB to 6MB to take into account better truesize tracking and to allow autotuning tcp receive window to reach same value than before. Note that same amount of kernel memory is consumed compared to 2.6 kernels. Signed-off-by: Eric Dumazet Cc: Neal Cardwell Cc: Tom Herbert Cc: Yuchung Cheng Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index bd80ba5847d2..1619a8c80873 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -147,7 +147,7 @@ tcp_adv_win_scale - INTEGER (if tcp_adv_win_scale > 0) or bytes-bytes/2^(-tcp_adv_win_scale), if it is <= 0. Possible values are [-31, 31], inclusive. - Default: 2 + Default: 1 tcp_allowed_congestion_control - STRING Show/set the congestion control choices available to non-privileged @@ -410,7 +410,7 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max net.core.rmem_max. Calling setsockopt() with SO_RCVBUF disables automatic tuning of that socket's receive buffer size, in which case this value is ignored. - Default: between 87380B and 4MB, depending on RAM size. + Default: between 87380B and 6MB, depending on RAM size. tcp_sack - BOOLEAN Enable select acknowledgments (SACKS). -- cgit v1.2.3 From 5f098a3ea72e73ad3733c3280fd5ee04816dc999 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Sat, 21 Apr 2012 17:40:12 +0530 Subject: ata: ahci_platform: Add synopsys ahci controller in DT's compatible list SPEAr13xx series of SoCs contain Synopsys AHCI SATA Controller which shares ahci_platform driver with other controller versions. This patch updates DT compatible list for ahci_platform. It also updates and renames binding documentation to more generic name. Signed-off-by: Viresh Kumar Cc: Rob Herring Signed-off-by: Jeff Garzik --- Documentation/devicetree/bindings/ata/ahci-platform.txt | 16 ++++++++++++++++ Documentation/devicetree/bindings/ata/calxeda-sata.txt | 17 ----------------- 2 files changed, 16 insertions(+), 17 deletions(-) create mode 100644 Documentation/devicetree/bindings/ata/ahci-platform.txt delete mode 100644 Documentation/devicetree/bindings/ata/calxeda-sata.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt new file mode 100644 index 000000000000..8bb8a76d42e8 --- /dev/null +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt @@ -0,0 +1,16 @@ +* AHCI SATA Controller + +SATA nodes are defined to describe on-chip Serial ATA controllers. +Each SATA controller should have its own node. + +Required properties: +- compatible : compatible list, contains "calxeda,hb-ahci" or "snps,spear-ahci" +- interrupts : +- reg : + +Example: + sata@ffe08000 { + compatible = "calxeda,hb-ahci"; + reg = <0xffe08000 0x1000>; + interrupts = <115>; + }; diff --git a/Documentation/devicetree/bindings/ata/calxeda-sata.txt b/Documentation/devicetree/bindings/ata/calxeda-sata.txt deleted file mode 100644 index 79caa5651f53..000000000000 --- a/Documentation/devicetree/bindings/ata/calxeda-sata.txt +++ /dev/null @@ -1,17 +0,0 @@ -* Calxeda SATA Controller - -SATA nodes are defined to describe on-chip Serial ATA controllers. -Each SATA controller should have its own node. - -Required properties: -- compatible : compatible list, contains "calxeda,hb-ahci" -- interrupts : -- reg : - -Example: - sata@ffe08000 { - compatible = "calxeda,hb-ahci"; - reg = <0xffe08000 0x1000>; - interrupts = <115>; - }; - -- cgit v1.2.3