| /openbmc/linux/kernel/ |
| H A D | Kconfig.preempt | 1 # SPDX-License-Identifier: GPL-2.0-only
37 This option reduces the latency of the kernel by adding more
40 latency of rescheduling, providing faster application reactions,
44 low priority process to voluntarily preempt itself even if it
52 bool "Preemptible Kernel (Low-Latency Desktop)"
56 This option reduces the latency of the kernel by making
59 permitting a low priority process to be preempted involuntarily
67 embedded system with latency requirements in the milliseconds
71 bool "Fully Preemptible Kernel (Real-Time)"
75 This option turns the kernel into a real-time kernel by replacing
[all …]
|
| /openbmc/linux/Documentation/block/ |
| H A D | bfq-iosched.rst | 5 BFQ is a proportional-share I/O scheduler, with some extra
6 low-latency capabilities. In addition to cgroups support (blkio or io
9 - BFQ guarantees a high system and application responsiveness, and a
10 low latency for time-sensitive applications, such as audio or video
12 - BFQ distributes bandwidth, and not just time, among processes or
16 In its default configuration, BFQ privileges latency over
17 throughput. So, when needed for achieving a lower latency, BFQ builds
19 goal, for a given device, is to achieve the maximum-possible
20 throughput at all times, then do switch off all low-latency heuristics
23 latency and throughput, or on how to maximize throughput.
[all …]
|
| H A D | deadline-iosched.rst | 10 -----------------------
11 Refer to Documentation/block/switching-sched.rst for information on
12 selecting an io scheduler on a per-device basis.
14 ------------------------------------------------------------------------------
17 -----------------------
27 -----------------------
33 ------------------------------------
40 This parameter tunes the balance between per-request latency and aggregate
41 throughput. When low latency is the primary concern, smaller is better (where
42 a value of 1 yields first-come first-served behaviour). Increasing fifo_batch
[all …]
|
| /openbmc/linux/drivers/net/wireless/intel/iwlwifi/mvm/ |
| H A D | quota.c | 1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
3 * Copyright (C) 2012-2014, 2018, 2021-2022 Intel Corporation
4 * Copyright (C) 2013-2014 Intel Mobile Communications GmbH
5 * Copyright (C) 2016-2017 Intel Deutschland GmbH
8 #include "fw-api.h"
33 if (vif == data->disabled_vif) in iwl_mvm_quota_iterator()
36 if (!mvmvif->deflink.phy_ctxt) in iwl_mvm_quota_iterator()
40 id = mvmvif->deflink.phy_ctxt->id; in iwl_mvm_quota_iterator()
48 switch (vif->type) { in iwl_mvm_quota_iterator()
50 if (vif->cfg.assoc) in iwl_mvm_quota_iterator()
[all …]
|
| /openbmc/linux/Documentation/devicetree/bindings/arm/msm/ |
| H A D | qcom,idle-state.txt | 3 ARM provides idle-state node to define the cpuidle states, as defined in [1].
4 cpuidle-qcom is the cpuidle driver for Qualcomm SoCs and uses these idle
5 states. Idle states have different enter/exit latency and residency values.
6 The idle states supported by the QCOM SoC are defined as -
26 Retention: Retention is a low power state where the core is clock gated and
31 state. Retention may have a slightly higher latency than Standby.
44 code in the EL for the SoC. On SoCs with write-back L1 cache, the cache has to
50 be flushed, system bus, clocks - lowered, and SoC main XO clock gated and
51 voltages reduced, provided all cpus enter this state. Since the span of low
52 power modes possible at this state is vast, the exit latency and the residency
[all …]
|
| /openbmc/linux/arch/alpha/lib/ |
| H A D | ev6-stxncpy.S | 1 /* SPDX-License-Identifier: GPL-2.0 */
3 * arch/alpha/lib/ev6-stxncpy.S
4 * 21264 version contributed by Rick Gorton <rick.gorton@api-networks.com>
6 * Copy no more than COUNT bytes of the null-terminated string from
29 * Furthermore, v0, a3-a5, t11, and $at are untouched.
34 * ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html
36 * E - either cluster
37 * U - upper subcluster; U0 - subcluster U0; U1 - subcluster U1
38 * L - lower subcluster; L0 - subcluster L0; L1 - subcluster L1
66 lda t2, -1 # E : build a mask against false zero
[all …]
|
| H A D | ev6-stxcpy.S | 1 /* SPDX-License-Identifier: GPL-2.0 */
3 * arch/alpha/lib/ev6-stxcpy.S
4 * 21264 version contributed by Rick Gorton <rick.gorton@alpha-processor.com>
6 * Copy a null-terminated string from SRC to DST.
21 * Furthermore, v0, a3-a5, t11, and t12 are untouched.
26 * ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html
28 * E - either cluster
29 * U - upper subcluster; U0 - subcluster U0; U1 - subcluster U1
30 * L - lower subcluster; L0 - subcluster L0; L1 - subcluster L1
58 lda t2, -1 # E : build a mask against false zero
[all …]
|
| /openbmc/linux/block/ |
| H A D | Kconfig | 1 # SPDX-License-Identifier: GPL-2.0
18 - block device files will become unusable
19 - some filesystems (such as ext3) will become unavailable.
86 support for ZAC/ZBC/ZNS host-managed and host-aware zoned block
101 See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information.
104 bool "Block throttling .low limit interface support (EXPERIMENTAL)"
107 Add .low limit interface for block throttling. The low limit is a best
128 Enable writeback throttling by default for request-based block devices.
131 bool "Enable support for latency based cgroup IO protection"
134 Enabling this option enables the .latency interface for IO throttling.
[all …]
|
| H A D | blk-throttle.c | 1 // SPDX-License-Identifier: GPL-2.0
14 #include "blk-cgroup-rwstat.h"
15 #include "blk-stat.h"
16 #include "blk-throttle.h"
31 #define DFL_LATENCY_TARGET (-1L)
36 * For HD, very small latency comes from sequential IO. Such IO is helpless to
46 /* We measure latency for request size from <= 4k to >= 1M */
55 unsigned long latency; /* ns / 1024 */ member
94 return pd_to_blkg(&tg->pd); in tg_to_blkg()
98 * sq_to_tg - return the throl_grp the specified service queue belongs to
[all …]
|
| H A D | Kconfig.iosched | 1 # SPDX-License-Identifier: GPL-2.0
14 The Kyber I/O scheduler is a low-overhead scheduler suitable for
16 synchronous writes, it will self-tune queue depths to achieve that
23 BFQ I/O scheduler for BLK-MQ. BFQ distributes the bandwidth of
26 also guarantees a low latency to interactive and soft
27 real-time applications. Details in
28 Documentation/block/bfq-iosched.rst
38 (cgroups-v1) or io (cgroups-v2) controller.
|
| /openbmc/linux/Documentation/networking/device_drivers/ethernet/intel/ |
| H A D | e1000e.rst | 1 .. SPDX-License-Identifier: GPL-2.0+
8 Copyright(c) 2008-2018 Intel Corporation.
13 - Identifying Your Adapter
14 - Command Line Parameters
15 - Additional Configurations
16 - Support
48 ---------------------
49 :Valid Range: 0,1,3,4,100-100000
53 vector can generate per second. Increasing ITR lowers latency at the cost of
60 but will increase latency as packets are not processed as quickly.
[all …]
|
| H A D | e1000.rst | 1 .. SPDX-License-Identifier: GPL-2.0+
8 Copyright(c) 1999 - 2013 Intel Corporation.
13 - Identifying Your Adapter
14 - Command Line Parameters
15 - Speed and Duplex Configuration
16 - Additional Configurations
17 - Support
50 -------
54 :Valid Range: 0x01-0x0F, 0x20-0x2F
57 This parameter is a bit-mask that specifies the speed and duplex settings
[all …]
|
| /openbmc/linux/arch/mips/cavium-octeon/ |
| H A D | Kconfig | 1 # SPDX-License-Identifier: GPL-2.0
11 non-CN63XXP1 hardware, so it is recommended to select "n"
41 Lock the low level TLB fast path into L2.
48 Lock the low level exception handler into L2.
55 Lock the low level interrupt handler into L2.
84 tristate "Module to measure interrupt latency using Octeon CIU Timer"
86 This driver is a module to measure interrupt latency using the
90 will be called octeon-ilm
|
| /openbmc/linux/Documentation/devicetree/bindings/memory-controllers/ |
| H A D | st,stm32-fmc2-ebi-props.yaml | 1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
3 ---
4 $id: http://devicetree.org/schemas/memory-controllers/st,stm32-fmc2-ebi-props.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
10 - Christophe Kerello <christophe.kerello@foss.st.com>
11 - Marek Vasut <marex@denx.de>
14 st,fmc2-ebi-cs-transaction-type:
33 st,fmc2-ebi-cs-cclk-enable:
40 st,fmc2-ebi-cs-mux-enable:
46 st,fmc2-ebi-cs-buswidth:
[all …]
|
| /openbmc/linux/Documentation/sound/cards/ |
| H A D | emu10k1-jack.rst | 2 Low latency, multichannel audio with JACK and the emu10k1/emu10k2
5 This document is a guide to using the emu10k1 based devices with JACK for low
6 latency, multichannel recording functionality. All of my recent work to allow
12 - Lee Revell, 2005.03.30
15 Until recently, emu10k1 users on Linux did not have access to the same low
16 latency, multichannel features offered by the "kX ASIO" feature of their
25 fairly self explanatory - select Duplex, then for capture and playback select
30 /usr/local/bin/jackd -R -dalsa -r48000 -p64 -n2 -D -Chw:0,2 -Phw:0,3 -S
36 sb-live-mixer.rst (or audigy-mixer.rst).
|
| /openbmc/linux/include/net/caif/ |
| H A D | caif_device.h | 1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) ST-Ericsson AB 2010
16 * struct caif_dev_common - data shared between CAIF drivers and stack.
19 * Link Layer to send flow-stop to CAIF Core.
23 * @link_select: Profile of device, either high-bandwidth or
24 * low-latency. This member is set by CAIF Link
26 * is a high bandwidth or low latency device.
|
| /openbmc/linux/Documentation/networking/ |
| H A D | tcp-thin.rst | 1 .. SPDX-License-Identifier: GPL-2.0
4 Thin-streams and TCP
7 A wide range of Internet-based services that use reliable transport
8 protocols display what we call thin-stream properties. This means
9 that the application sends data with such a low rate that the
11 effective. In time-dependent scenarios (like online games, control
13 on the data delivery latency, packet loss can be devastating for
19 After analysing a large number of time-dependent interactive
22 lifespan. The combination of time-dependency and the fact that the
25 In order to reduce application-layer latency when packets are lost,
[all …]
|
| /openbmc/linux/Documentation/admin-guide/pm/ |
| H A D | intel_idle.rst | 1 .. SPDX-License-Identifier: GPL-2.0
24 Documentation/admin-guide/pm/cpuidle.rst if you have not done that yet.]
28 processor's functional blocks into low-power states. That instruction takes two
38 only way to pass early-configuration-time parameters to it is via the kernel
42 .. _intel-idle-enumeration-of-states:
50 as C-states (in the ACPI terminology) or idle states. The list of meaningful
51 ``MWAIT`` hint values and idle states (i.e. low-power configurations of the
56 subsystem (see :ref:`idle-states-representation` in
57 Documentation/admin-guide/pm/cpuidle.rst),
66 `below <intel-idle-parameters_>`_.]
[all …]
|
| /openbmc/linux/Documentation/usb/ |
| H A D | ehci.rst | 5 27-Dec-2002
8 USB 2.0-capable host controller hardware. The USB 2.0 standard is
11 - "High Speed" 480 Mbit/sec (60 MByte/sec)
12 - "Full Speed" 12 Mbit/sec (1.5 MByte/sec)
13 - "Low Speed" 1.5 Mbit/sec
15 USB 1.1 only addressed full speed and low speed. High speed devices
23 (TT) in the hub, which turns low or full speed transactions into
31 While usb-storage devices have been available since mid-2001 (working
34 appear to be on hold until more systems come with USB 2.0 built-in.
39 other changes to the Linux-USB core APIs, including the hub driver,
[all …]
|
| /openbmc/phosphor-dbus-interfaces/yaml/xyz/openbmc_project/Inventory/Item/ |
| H A D | Dimm.interface.yaml | 4 - name: MemoryDataWidth
8 - name: MemorySizeInKB
12 - name: MemoryDeviceLocator
16 - name: MemoryType
20 - name: MemoryTypeDetail
24 - name: MaxMemorySpeedInMhz
28 - name: MemoryAttributes
33 - name: MemoryConfiguredSpeedInMhz
37 - name: ECC
40 Error-Correcting Code.
[all …]
|
| /openbmc/u-boot/drivers/ddr/fsl/ |
| H A D | ddr2_dimm_params.c | 1 // SPDX-License-Identifier: GPL-2.0
18 * --- ----- ------
26 * 0 low 1GB 1GB
46 * Convert a two-nibble BCD value into a cycle time.
47 * While the spec calls for nano-seconds, picos are returned.
143 * CAS latency given the DRAM clock period. The SPD only
145 * frequency the DIMM runs at, the shorter its CAS latency can.
146 * be. If the DIMM is operating at a sufficiently low frequency,
147 * it may be able to run at a CAS latency shorter than the
148 * shortest SPD-defined CAS latency.
[all …]
|
| H A D | ddr1_dimm_params.c | 1 // SPDX-License-Identifier: GPL-2.0
19 * --- ----- ------
27 * 0 low 1GB 1GB
47 * Convert a two-nibble BCD value into a cycle time.
48 * While the spec calls for nano-seconds, picos are returned.
162 * CAS latency given the DRAM clock period. The SPD only
164 * frequency the DIMM runs at, the shorter its CAS latency can be.
165 * If the DIMM is operating at a sufficiently low frequency,
166 * it may be able to run at a CAS latency shorter than the
167 * shortest SPD-defined CAS latency.
[all …]
|
| /openbmc/linux/include/uapi/linux/caif/ |
| H A D | caif_socket.h | 1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
4 * Copyright (C) ST-Ericsson AB 2010
16 * enum caif_link_selector - Physical Link Selection.
17 * @CAIF_LINK_HIGH_BANDW: Physical interface for high-bandwidth
19 * @CAIF_LINK_LOW_LATENCY: Physical interface for low-latency
32 * enum caif_channel_priority - CAIF channel priorities.
35 * @CAIF_PRIO_LOW: Low-priority channel.
55 * enum caif_protocol_type - CAIF Channel type.
78 * enum caif_at_type - AT Service Endpoint
85 * enum caif_debug_type - Content selection for debug connection
[all …]
|
| /openbmc/linux/drivers/net/ethernet/amazon/ena/ |
| H A D | ena_admin_defs.h | 1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
3 * Copyright 2015-2020 Amazon.com, Inc. or its affiliates. All rights reserved.
59 /* descriptors and headers are in device memory (a.k.a Low Latency
119 * 1 : ctrl_data - control buffer address valid
120 * 2 : ctrl_data_indirect - control buffer address
142 * 7:5 : sq_direction - 0x1 - Tx; 0x2 - Rx
193 * 7:5 : sq_direction - 0x1 - Tx, 0x2 - Rx
199 /* 3:0 : placement_policy - Describing where the SQ
201 * 0x1 - descriptors and headers are in OS memory,
202 * 0x3 - descriptors and headers in device memory
[all …]
|
| /openbmc/linux/kernel/trace/ |
| H A D | trace_hwlat.c | 1 // SPDX-License-Identifier: GPL-2.0
3 * trace_hwlat.c - A simple Hardware Latency detector.
20 * Although certain hardware-inducing latencies are necessary (for example,
22 * and remote management) they can wreak havoc upon any OS-level performance
23 * guarantees toward low-latency, especially when the OS is not even made
27 * sampling the built-in CPU timer, looking for discontiguous readings.
31 * environment requiring any kind of low-latency performance
34 * Copyright (C) 2008-2009 Jon Masters, Red Hat, Inc. <jcm@redhat.com>
35 * Copyright (C) 2013-2016 Steven Rostedt, Red Hat, Inc. <srostedt@redhat.com>
67 static char *thread_mode_str[] = { "none", "round-robin", "per-cpu" };
[all …]
|