| Age | Commit message (Collapse) | Author |
|
The Kconfig description of the vxcan kernel module erroneously states the
the vxcan interface does not provide a local echo of sent can frames.
However this behavior changed in commit 259bdba27e32 ("vxcan: enable local
echo for sent CAN frames") and vxcan interfaces now provide a local echo.
Change the description of the vxcan module in the Kconfig to reflect this
change.
Signed-off-by: Alexander Hölzl <alexander.hoelzl@gmx.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260619090035.17769-1-alexander.hoelzl@gmx.net
[mkl: rephrase patch description]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
|
|
An imported dma-buf BO is created as a ttm_bo_type_sg BO whose
reservation object is the exporter's dma_buf->resv. The importer,
however, only takes a dma-buf reference after a successful
dma_buf_dynamic_attach(). Until then nothing keeps the exporter alive,
so if the exporter is freed while the BO still references its resv, a
later access to that resv is a use-after-free:
Oops: general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b9c
Workqueue: ttm ttm_bo_delayed_delete [ttm]
RIP: 0010:mutex_can_spin_on_owner+0x3f/0xc0
This can be reached on two paths:
- dma_buf_dynamic_attach() fails, or
- ttm_bo_init_reserved() fails during BO creation.
In both cases the BO already has bo->base.resv pointing at the exporter
resv, and sg BOs are always torn down via ttm_bo_delayed_delete(), which
locks bo->base.resv asynchronously - potentially after the exporter has
been freed.
Take the dma-buf reference in xe_bo_init_locked(), before
ttm_bo_init_reserved(), so it also covers a creation failure there, and
release it in xe_ttm_bo_destroy(). The reference is held for the whole
BO lifetime, keeping the shared resv alive on every path.
v2:
- Reworked the fix to avoid creating the imported sg BO before
dma_buf_dynamic_attach() succeeds.
- Attach with importer_priv == NULL and make invalidate_mappings ignore
incomplete imports.
v3:
- Dropped the xe-side reordering approach since importer_priv must be
valid when dma_buf_dynamic_attach() publishes the attachment.
- Per Christian's suggestion on the v1 thread, keyed the check on
import_attach rather than removing the sg guard entirely.
- Fixes both xe and amdgpu in a single TTM patch.
v4:
- Moved import_attach check to after dma_resv_copy_fences() so fences
are copied before returning for successful imports (Thomas).
- Removed exporter-alive claim from commit message (Thomas).
v5:
- Add drm/xe patch to keep imported sg BOs off the LRU before attach
succeeds; the TTM fix alone is not sufficient for xe if the BO is
already LRU-visible. (Thomas)
v4 patch:
https://patchwork.freedesktop.org/patch/736663/?series=169129&rev=2
- Patch 1 (drm/ttm) carries Christian's Reviewed-by from v4.
v6:
- Reworked the fix based on Thomas' suggestion. Instead of the TTM resv
individualization (v1-v5) plus the xe off-LRU/placement handling (v5),
just hold a dma-buf reference for the imported BO lifetime so the
shared resv can never be freed while the BO still references it.
Single xe patch, no TTM change. (Thomas)
- Take the reference in xe_bo_init_locked() before ttm_bo_init_reserved()
so a TTM creation failure is covered too (Thomas).
- Dropped the v5 series (drm/ttm + drm/xe off-LRU); the off-LRU approach
also regressed in CI BAT via ttm_bo_pipeline_gutting() creating a ghost
BO that outlived the exporter.
Link to v5: https://patchwork.freedesktop.org/series/169984/
v7:
- Move changelog above --- so it stays in the commit message.
- Reorder changelog entries oldest-to-newest. (Thomas)
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/8023
Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Cc: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>
Cc: Christian Konig <christian.koenig@amd.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Suggested-by: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>
Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patch.msgid.link/20260710191027.260160-2-nitin.r.gote@intel.com
|
|
The RZ/G3E SoC supports up to 8 GiB of memory. Update the PCIe dma-ranges
property to use the 64-bit prefetchable memory space code.
Fixes: 1ac57c9830cb ("arm64: dts: renesas: r9a09g047: Add PCIe node")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260708172849.227915-3-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
The RZ/V2N SoC supports up to 8 GiB of memory. Update the PCIe dma-ranges
property to use the 64-bit prefetchable memory space code.
Fixes: 4c443296ff17 ("arm64: dts: renesas: r9a09g056: Add PCIe node")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260708172849.227915-2-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Enable the PCIE1 slot which is connected to PCIe0 channel.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260708163311.222176-3-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add PCIe nodes to Renesas RZ/V2H(P) ("R9A09G057") SoC DTSI.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260708163311.222176-2-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Activate the FRAM and the SPI bus which it is attached to.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260626180326.9593-5-wsa+renesas@sang-engineering.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add nodes for the 6 SPI controllers of the Renesas RZ/N1D SoC.
The first 4 can only be controllers, the latter 2 can only be targets.
DMA nodes are not added yet because DMA needs some extra code in the
drivers and cannot be tested yet. Basic FIFO mode works reliably,
though.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260626180326.9593-4-wsa+renesas@sang-engineering.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add memory nodes for the RZ/T2H and RZ/N2H EVK boards.
These boards populate 8GiB of DDR memory, which is exposed through two
address ranges.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260622170733.1703585-1-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add soc: labels to the /soc {} nodes to align DTS with r8a77951.dtsi
which already has that soc: label. The soc: label is useful in U-Boot
where it is used in U-Boot extras DT fragments.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260621025052.406507-1-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-2-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-3-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-4-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-5-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-6-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-7-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-8-marek.vasut+renesas@mailbox.org
Link: https://patch.msgid.link/20260621025052.406507-9-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
RZ/G3E SMARC board has a DA7212 audio codec connected via I2C1 for
sound input/output using SSI3/SSI4 where:
- The codec receives its master clock from the Versa3 clock
generator present on the SoM,
- SSI4 shares clock pins with SSI3 to provide a separate data
line for full-duplex audio capture.
Enable audio support on RZ/G3E SMARC2 EVK boards with a DA7212 audio
codec.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Link: https://patch.msgid.link/20260619083951.3777556-5-john.madieu.xa@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add pinmux definitions for SSI3/SSI4 audio interface on RZ/G3E SMARC SoM:
- sound_clk_pins: AUDIO_CLKB and AUDIO_CLKC clock outputs,
- sound_pins: SSI3_SCK, SSI3_WS, SSI3_SDATA (playback) and
SSI4_SDATA (capture).
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260619083951.3777556-4-john.madieu.xa@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add the Renesas 5P35023 (Versa3) programmable clock generator on the
I2C2 bus along with its 24MHz input clock (x2 oscillator) to feed the
audio subsystem.
The Versa3 provides the following clock outputs:
- Output 0: 24MHz (reference),
- Output 1: 12.288MHz (audio, 48kHz family),
- Output 2: 11.2896MHz (audio, 44.1kHz family),
- Output 3: 12.288MHz (audio),
- Output 4: 25MHz (DIFF1, Ethernet).
These clocks are required for the audio codec and the Ethernet
controller found on the RZ/G3E SMARC EVK.
Output 5 (DIFF2) is left out, as it is not connected on this board.
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260619083951.3777556-3-john.madieu.xa@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add the snd_rzg3e node for the RZ/G3E SoC with all sub-components:
- SSI (Serial Sound Interface) units 0-9,
- SSIU (Serial Sound Interface Unit) units 0-27,
- SRC (Sample Rate Converter) units 0-9,
- CTU (Channel Transfer Unit) units 0-7,
- DVC (Digital Volume Control) units 0-1,
- MIX (Mixer) units 0-1.
Sub-node names follow the new RZ/G3E sound binding: unprefixed 'ssi',
'ssiu', 'src', 'dvc', 'mix', 'ctu' wrapper nodes instead of the legacy
'rcar_sound,xxx' R-Car prefix.
Wire up all 5 DMA controllers (dmac0-dmac4) for each audio sub-node with
repeated channel names, so that the DMA core can pick the first
available controller.
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260619083951.3777556-2-john.madieu.xa@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Enable GPU on M3NULCB with R-Car M3-N.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://patch.msgid.link/20260611005952.146825-3-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Enable GPU on Salvator-X 2nd version with R-Car M3-N.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://patch.msgid.link/20260611005952.146825-2-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Enable GPU on Salvator-X with R-Car M3-N.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://patch.msgid.link/20260611005952.146825-1-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add the SPU bus clock, icka/b functional clocks, and xcka/b external
clock inputs to the FSI device node.
This prepares for subsequent driver changes that explicitly manage the
SPU clock required for FSI register access on R-Mobile A1.
Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260609113836.45079-3-phucduc.bui@gmail.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add max-frequency properties of 200MHz to the sdhi0, sdhi1, and sdhi2
MMC controllers in the R9A09G047 SoC DTSI to define the maximum
supported bus frequency.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260603143340.162457-3-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Rsci4 is routed to either the PMOD connector or the M.2 connector,
depending on the SW_SER0_PMOD switch state. In both cases, rsci4 is
available for use, so there is no need to guard it with SW_SER0_PMOD.
Drop the SW_SER0_PMOD condition and retain only the SW_LCD_EN check,
as rsci4 is unavailable only when the LCD is enabled.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260603143340.162457-2-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Describe the MFIS core which is used for various tasks including
inter-processor communication. Interrupt numbers look irregular but
they all work as expected on a Renesas R-Car V4H SparrowHawk board.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260602182157.304964-2-wsa+renesas@sang-engineering.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add PSCI "enable-method" DT properties to all application CPU cores.
This allows the OS to bring application CPU cores up and down.
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260601113919.8327-1-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Enable RSPI2 on the RZ/G3L SMARC EVK board by adding pin control
configuration and activating the rspi2 node.
The RSPI2 pins are shared with the DPI display interface and the
two cannot be used simultaneously. This is controlled by switch
SW_DPI_EN.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260529130704.327505-3-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add device tree nodes for the three RSPI channels on the RZ/G3L
(R9A08G046) SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260529130704.327505-2-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Enable rsci{1,2,3} device nodes for the RZ/G3L SMARC EVK.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260529125442.327290-1-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Configure the drive strength, slew rate, and Schmitt trigger settings for
the sci0 pin group shared by the RZ/T2H and RZ/N2H EVK boards.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260528134752.79813-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Update the gmac1 (ETH3) and gmac2 (ETH2) pin configurations on the
RZ/T2H and RZ/N2H EVK boards to comply with the electrical specifications
defined in Table 58.11 of the hardware user manual.
While restructuring the nodes into pin groups, fix a copy-paste comment
typo in the RZ/N2H device tree where the ETH3_TXD1 pin mux configuration
was mistakenly labeled as ETH3_TXD0.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260528134752.79813-3-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Remove the unused TXER, RXER, CRS, and COL pinmux configurations from the
gmac1 (ETH3) and gmac2 (ETH2) pin groups.
The Ethernet interfaces on both the RZ/T2H and RZ/N2H EVK boards operate
in RGMII mode, which does not utilize these extra MII/GMII sideband signal
pins. Update the board switch configuration comments to accurately reflect
the pin ranges that are actually in use.
Fixes: b272b94fd2239 ("arm64: dts: renesas: rzt2h-n2h-evk: Enable Ethernet support")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260528134752.79813-2-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Add and enable I2C1 controller support with pin configuration.
The I2C1 bus is routed to the carrier board and used for peripherals
such as the audio codec.
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260525110603.4018170-7-john.madieu.xa@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
Model the optional external audio clock inputs as CPG input clocks for
RZ/V2H family SoCs (RZ/V2H, RZ/V2N, RZ/G3E), allowing the Audio Clock
Generator (ADG) to derive internal audio clocks from these external
sources.
The clock frequencies are board-specific and must be overridden in the
board DTS files.
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260525110603.4018170-4-john.madieu.xa@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
The DBSC5 DRAM controller protects DRAM content using inline ECC.
The inline ECC utilizes areas of DRAM for its operation, which are
in the DRAM address range, but must not be accessed or modified.
Describe the inline ECC carveout areas used by the DBSC5 controller
on this hardware as reserved-memory, which must not be accessed.
Include DRAM areas which are unprotected by ECC as well, those are
parts of the DRAM which directly precede the ECC carveout.
In case of high DRAM utilization, unless the inline ECC carveouts
are properly reserved, Linux may use and corrupt the memory used
by the DBSC5 DRAM controller for inline ECC, which would lead to
the system becoming unstable.
Fixes: ad142a4ef710 ("arm64: dts: renesas: r8a78000: Add initial Ironhide board support")
Cc: stable@vger.kernel.org
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260710160450.64967-1-marek.vasut+renesas@mailbox.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
|
|
|
|
Add a fault-injection mode to the scx_qmap sub-scheduler that deliberately
dispatches one of its own tasks to a cid it does not hold. The kernel cap
check must reject it and re-enqueue with SCX_TASK_REENQ_CAP, so the
nr_inject_attempts counter tracks nr_reenq_cap one to one, exercising the
delivery-time cap enforcement.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
sched_ext sub-scheduling began as dispatch delegation only: a parent could
call into a child cgroup sub-scheduler's ops.dispatch() from its own
dispatch path, but could not delegate cpus to the child for enqueue and the
other paths. sched_ext has since gained cap-based cid delegation, where a
parent grants and revokes a child's per-cid caps. Expand scx_qmap to
demonstrate it.
scx_qmap can now delegate the cids it holds exclusively, split among itself
and its children by cpu.weight. Each gets the floor of its share as
dedicated cids. The leftover from rounding forms a shared pool,
round-robined among them as an ENQ_IMMED time-share.
This shape is deliberate. Exclusive cids exercise the basic grant and revoke
of ownership, and the shared pool exercises time-sharing one cid across
several schedulers. The implemented policy is impractical, but it covers
most of what a practical sub-scheduler would need without overcomplicating
qmap.
Delegation nests. A cid a node receives from its parent only as a
round-robin share stays self-local and is never re-delegated. A node left
with no exclusive cid, e.g. after its cpus went offline, evicts its
children.
v5: Highpri dispatch masked with self_cids, single-read dispatch cgroup_id, feed_weights race comment. (sashiko AI)
v4: Track all idle cids and mask with self_cids at the dispatch pick, dropping the reseed. (sashiko AI)
v3: Dispatch IMMED flags, repartition accounting order, partition-input snapshot. (sashiko AI)
v2: Use __sync_fetch_and_add() for the shared nr_dsps counter. (sashiko AI)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
Add cmask_next_and2_set() and its round-robin wrap, extending
cmask_next_and_set() to a three-mask intersection: the next cid set in all
three masks at or after @start. A caller iterating the intersection of
three cmasks can then scan it in one pass, folding the third mask into the
word-level AND rather than skipping non-members one candidate at a time.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
A cid-form scheduler can grant caps to and revoke them from its child
sub-schedulers but has no way to tear one down. Add scx_bpf_sub_kill() to
evict a direct child with a printf-style reason that reaches the child's
scx_exit_info. No exit code is taken because the child is a separate
scheduler whose exit-code semantics the parent cannot know. The child and
its subtree are disabled through the usual async path under a new exit kind,
SCX_EXIT_PARENT_KILL.
The bstr formatting infrastructure in ext.c is exposed through internal.h
with scx_ prefixes so the kfunc, which lives in sub.c, can format the
reason.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
scx_process_sync_ecaps() consumes ecaps syncs while the sched is bypassing
without delivering ops.sub_ecaps_updated(), leaving reported_ecaps stale.
Nothing re-queued a sync when bypass lifted, so a cid whose caps never
change again would never be notified. Attach-time initial grants hit this
every time: they are consumed during the enable bypass window, so a sched
never learned its initial effective caps through the callback.
Re-queue a sync for every (sched, cpu) with an undelivered delta at the
per-cpu bypass exit in scx_bypass(), next to the idle renotify catch-up. The
next balance on the cpu then delivers the pending delta with proper dispatch
context.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
__scx_update_idle() notified only the root scheduler. A sub-scheduler that
holds a cid needs that cid's idle state to place and kick on it.
Deliver ops.update_idle() to every scheduler that holds SCX_CAP_BASE on the
transitioning cid. The root holds every cap, so a real transition always
reaches it.
Real transitions are not enough on their own. A cid that is already idle
when a sub-sched gains baseline access produces no transition, so the new
holder would never learn it is idle. The ecaps sync arms a re-notify on the
gain, and the next idle pick delivers ops.update_idle() to just that sched,
leaving holders that already track the cpu untouched. A matching loss of
baseline access drops any pending re-notify.
Bypass suppresses ops.update_idle() too, so a cpu that goes idle during a
bypass window and stays idle yields no transition to re-deliver on
un-bypass. Arm the same re-notify for every sched leaving bypass. The acute
case is a child granted cids during its own ops.sub_attach(). The grant
lands while the child is bypassed and the notify walk skips it, so on
un-bypass it holds cids it never saw go idle. The root is owed the same and
is armed through a separate per-rq flag, which keeps this working when
sub-schedulers are compiled out.
v2: Gate the idle catch-up in pick_task_idle() to avoid a double ops.update_idle(). (sashiko AI)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
scx_local_or_reject_dsq() authorizes a local-DSQ insert against the caps
of the scheduler doing the insert. On the consume/dispatch paths that is
the scheduler running balance_one(), passed down through
scx_consume_dispatch_q() and move_local_task_to_local_dsq(), so the check
is correct.
The remote-move path loses it. move_remote_task_to_local_dsq()
re-activates @p on the destination rq through enqueue_task_scx(), which
reconstructs the scheduler from the task, i.e. @p's owner. When an
ancestor places a descendant's task - e.g. draining a bypassed
sub-scheduler - the owner is a sub-scheduler of the placer, so
authorizing against the owner checks a narrower cap set and can
spuriously reject a task the placer is entitled to run.
Carry the placing scheduler across the activate_task() boundary the same
way enq_flags already are, via a per-rq field set only for the duration
of the re-activation, and have scx_local_or_reject_dsq() authorize
against it. The placer's caps are a superset of the owner's, so this
admits what the placer may run and keeps rejecting what it may not.
v2: Document @sch in move_remote_task_to_local_dsq()'s kerneldoc. (Andrea)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
A kick forces a scheduling event on the target cpu, and a preemption also
evicts the running task. Gate both on caps. Any kick requires baseline
access on the cid, and preempting a task the sub-sched does not own -
whether by a SCX_ENQ_PREEMPT insert or a SCX_KICK_PREEMPT kick - requires
the new SCX_CAP_PREEMPT. Gating either alone would leave a hole - the
weakest cap authorizing preempting kicks, or plain kicks disturbing cpus the
kicker has no access to.
Preempting the sched's own subtree is always allowed, and the cap extends
the right to any task on the cid. PREEMPT implies ENQ, and so ENQ_IMMED.
A preempting insert tests the running task under the target rq lock and is
rejected and reenqueued unless the victim is in the inserter's subtree or it
holds PREEMPT. A migration-disabled task is admitted regardless, but with
SCX_ENQ_PREEMPT stripped.
Kicks are enforced on the delivery path, where the effective caps can be
read coherently under the target rq's lock. A kick from a sub-sched lacking
SCX_CAP_BASE on the cid is dropped, and a SCX_KICK_PREEMPT kick without
PREEMPT for a task outside the kicker's subtree degrades to a plain
reschedule.
Unlike the enqueue caps, PREEMPT is checked only at the instant of the
insert or kick, never as a standing property of a queued task.
v2: Clear SCX_ENQ_PREEMPT on the offline and migration_pending force-admits.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
Add SCX_CAP_ENQ, which gates inserting tasks onto a cid's local DSQ. Unlike
IMMED enqueue, plain enqueues can pile up, so ENQ is the stronger cap and
implies ENQ_IMMED. Losing ENQ also triggers the reenq scan. The scan tests
each queued task and the running task against the cap each needs via
scx_caps_for_task(), so an ENQ-only loss reenqueues plain tasks, evicting a
running one, while IMMED tasks, which need only ENQ_IMMED, stay put.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
A task's slice grants it cpu occupancy - how long it holds its cpu. In a
sub-scheduler hierarchy cpu access is delegated through revocable
capabilities, so a task's occupancy must follow them. Only its own scheduler
sets its slice, and extending the slice is allowed only while that scheduler
holds baseline cpu access (SCX_CAP_BASE) on the cpu. Otherwise a scheduler
could keep occupying a cpu it has been denied simply by handing out long
slices.
The cap check reads effective caps, which are coherent only under the task's
rq lock, and the kernel decrements the slice under that lock as the task
runs, so a running task's slice can be changed only there while a queued
task's can be set directly. Make scx_bpf_task_set_slice() apply the slice
under the rq lock. Synchronously when the caller already holds it, otherwise
by stashing it in the new p->scx.slice_oob, tagged with the scheduler's id
so a request that outlived a reassignment is dropped. Whether the caller
holds @p's current rq lock is tested with p->scx.runnable_cpu.
Revocation is enforced through the same grant. When a cpu's effective caps
lose SCX_CAP_BASE, the cap-revoke reenq scan also checks the running task
and zeroes its slice to evict it. The scan runs as a balance callback after
the pick, so this catches both the task that was running when the revoke
landed and a capless task the pick just promoted off the local DSQ. The
paths that keep a task on its cpu - holding on to the last runnable task in
balance, the ENQ_LAST reinsertion and the slice refill on pick - skip tasks
lacking baseline access. A migration-disabled task is exempt, mirroring its
capless admission on insert.
v4: Test rq ownership with p->scx.runnable_cpu, closing a remote-wakeup TOCTOU. (sashiko AI)
v3: Keep a pending out-of-band slice request across refill and preserve. (sashiko AI)
v2: Only write slice directly when @p is queued on the held rq. (sashiko AI)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
Add p->scx.runnable_cpu, the cpu @p is runnable on, or -1 when it is not.
It is stamped as @p joins the runnable_list (set_task_runnable()) and
cleared as it leaves (clr_task_runnable()), both under the rq lock.
task_cpu() can't answer "is @p on this rq" reliably: a remote wakeup changes
it under @p's pi_lock alone, without the source rq lock, so it can read as
the locked rq while @p is really elsewhere. runnable_cpu changes only under
the rq lock, so a caller holding an rq lock can compare against it to know
whether that is @p's current rq.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
A later change makes set_task_slice() also drop a pending out-of-band slice
request, so the BPF-triggered writes to p->scx.slice need to funnel through
one place. Introduce set_task_slice() and route those writes through it.
update_curr_scx() decrements curr->scx.slice directly for accounting and is
left alone. No functional change - the helper only assigns p->scx.slice.
v2: Reword the set_task_slice comment to "BPF-triggered writes". (Andrea)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
Neither a scx_sched pointer nor its cgroup id uniquely identifies a
scheduler instance. A freed sched's memory can be reallocated, and a cgroup
can detach one sched and attach another. Add a monotonic, never-reused u64
id. A later patch compares it to drop a slice request that outlived a change
of a task's owning scheduler.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
Replace the __SCX_CAP_DUMMY placeholder with SCX_CAP_ENQ_IMMED, which gates
inserting IMMED tasks onto a cid's local DSQ. An IMMED enqueue is guaranteed
to either get its task running on the cpu at once or hand it back to the
scheduler, so IMMED work can never pile up on the cpu's queue and a cpu can
be shared across sub-scheds through IMMED access without any of them
swamping it.
That makes ENQ_IMMED the natural baseline, the minimal cap to make any use
of a cpu. SCX_CAP_BASE aliases it so gates on basic cpu access can state the
intention instead of naming ENQ_IMMED.
Enforcement covers inserts and queued tasks. An insert without the cap is
diverted to the reject DSQ, and queued tasks are reenqueued when the cap is
lost. scx_bpf_sub_dispatch() skips a child that lacks the cap on the cpu, as
its inserts would only be rejected. Vacating the running task on cap loss
lands in a later patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
A SAVE/RESTORE requeue re-inserts a running task in place and is immediately
followed by set_next_task_scx(). It is not a real scheduling event: the task
is already admitted to its cid and must return to the local DSQ
unconditionally.
scx_caps_for_enq() maps an enqueue to the cap its local-DSQ insert requires.
Add SCX_ENQ_IGNORE_CAPS, set it on the RESTORE-in-place branch of
enqueue_task_scx(), and have scx_caps_for_enq() require no caps for it, so
the cid admission gate never diverts an in-place restore to the reject DSQ.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
When a sub-scheduler dispatches a task to a CPU it lacks the required
capability on, the task must be rejected rather than allowed to run.
Add the machinery for that. Each rq gets a reject DSQ, a kernel-internal
holding queue that is never run and that the BPF scheduler cannot reach. An
insert that must be refused is diverted there instead of the local DSQ, and
a deferred requeue then hands the parked tasks back to the BPF scheduler to
re-decide. A cap revoke extends this to already-queued tasks. When the
revoke reaches the cpu's effective caps, the cpu scans its local DSQ and
reenqueues the tasks that no longer qualify.
A migration-disabled task must run on its cpu, so a capless one is admitted
anyway and counted in the new SCX_EV_SUB_FORCED_ADMIT event.
This is preparation for the actual sub-sched cap enforcement. The divert is
wired but inert here.
v2: Admit offline-rq and migration_pending inserts to local, not reject. (sashiko AI)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
The local DSQ is synchronized by the containing rq lock rather than its own
dsq->lock. A later patch adds a second such DSQ. In preparation, factor the
"rq owns the lock" test into dsq_is_rq_owned() and rename
local_dsq_post_enq() to rq_owned_post_enq(), taking @rq explicitly.
No behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|
|
A sub-scheduler that gains or loses effective caps on a cpu may want to act
on it right away - e.g. place or preempt on a newly usable cpu. The existing
ops.sub_caps_updated() doesn't fit as it is delivered asynchronously to
scheduling operations and can arrive before the per-cpu effective caps go
live.
Add ops.sub_ecaps_updated(cid, before, after), a cid-form callback fired
from scx_process_sync_ecaps() when a sub-sched's effective caps on a cid
change. It runs in dispatch context so the sched can insert, kick or preempt
on the cid directly. @before is the caps as of the last delivery.
Cpu hotplug rides the same machinery. Going down zeroes each sched's ecaps
on the cpu's cid, with queued syncs discarded at consumption while the cpu
is inactive. Coming back up queues a sync for every sched. reported_ecaps is
kept across the down/up cycle, so the resync fires the callback only if
ownership actually changed while the cpu was down.
v2: Compute cid below the active-cpu guard; discard queued syncs on !cpu_active(). (sashiko AI)
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
|