From patchwork Tue Mar 7 14:25:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Asahi Lina X-Patchwork-Id: 661387 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 011D0C678D4 for ; Tue, 7 Mar 2023 14:33:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230091AbjCGOdy (ORCPT ); Tue, 7 Mar 2023 09:33:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39010 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230505AbjCGOdY (ORCPT ); Tue, 7 Mar 2023 09:33:24 -0500 Received: from mail.marcansoft.com (marcansoft.com [212.63.210.85]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 65FA74BEA8; Tue, 7 Mar 2023 06:28:12 -0800 (PST) Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: linasend@asahilina.net) by mail.marcansoft.com (Postfix) with ESMTPSA id 5EAB44261B; Tue, 7 Mar 2023 14:28:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=asahilina.net; s=default; t=1678199290; bh=doeN3VcfbBkHfCBMFKL0Le01kutm2Kr1LQUm5Ywem7w=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=GYqT9JNT3L6LU++v+IEfjknM+AZUbhwj4/2tCosIWi63HlcrPjIkHAsYVH4O+HRoh /MK1Fz+pXAA8W6r/40fGfpVTaTKKc7Jo6IXfnzkk3SbGW1DPwKrmU7Bd4s/hQINSYD p/V4RdECpng1NGRC7Gsa8n1UBVwiSfagqcvn87ZDyAlrxPxXWA8m2WZD7c4YJPxvJs pBgJzqOZ63Fjk0pzr9F7uPMoz/At2X9VopIDHRyYgPG1W0B2AnWOSUuPyGjroFd94S SiWiTJPQ7imIUx0glBwHPZD1xbXzx17vvXwhGCsW/2YoBRuSvMgjiYMlhW9ISpQB/L S0pQ4/m2/oTEw== From: Asahi Lina Date: Tue, 07 Mar 2023 23:25:37 +0900 Subject: [PATCH RFC 12/18] rust: drm: sched: Add GPU scheduler abstraction MIME-Version: 1.0 Message-Id: <20230307-rust-drm-v1-12-917ff5bc80a8@asahilina.net> References: <20230307-rust-drm-v1-0-917ff5bc80a8@asahilina.net> In-Reply-To: <20230307-rust-drm-v1-0-917ff5bc80a8@asahilina.net> To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Sumit Semwal , =?utf-8?q?Christian_K=C3=B6nig?= , Luben Tuikov , Jarkko Sakkinen , Dave Hansen Cc: Alyssa Rosenzweig , Karol Herbst , Ella Stanforth , Faith Ekstrand , Mary , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, linux-sgx@vger.kernel.org, asahi@lists.linux.dev, Asahi Lina X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1678199191; l=14900; i=lina@asahilina.net; s=20230221; h=from:subject:message-id; bh=doeN3VcfbBkHfCBMFKL0Le01kutm2Kr1LQUm5Ywem7w=; b=v3jijRtVxCOMOLquRKYMJ9SpdkHB/Pr+MGkxG/X/94rpF3w8oSPPtB6SFTvw8sm6mScbBbVDZ G3PGDIj1/m4BKQgENwxSO1WUOpji5kpOOvLfL2+9gKEtTcQLwlr5OE8 X-Developer-Key: i=lina@asahilina.net; a=ed25519; pk=Qn8jZuOtR1m5GaiDfTrAoQ4NE1XoYVZ/wmt5YtXWFC4= Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The GPU scheduler manages scheduling GPU jobs and dependencies between them. This Rust abstraction allows Rust DRM drivers to use this functionality. Signed-off-by: Asahi Lina --- drivers/gpu/drm/Kconfig | 5 + rust/bindings/bindings_helper.h | 1 + rust/helpers.c | 6 + rust/kernel/drm/mod.rs | 2 + rust/kernel/drm/sched.rs | 358 ++++++++++++++++++++++++++++++++++++++++ 5 files changed, 372 insertions(+) diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 70a983a17ac2..8b5ad6aee126 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -39,6 +39,11 @@ config RUST_DRM_GEM_SHMEM_HELPER depends on RUST_DRM select DRM_GEM_SHMEM_HELPER +config RUST_DRM_SCHED + bool + depends on RUST_DRM + select DRM_SCHED + config DRM_MIPI_DBI tristate depends on DRM diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index b6696011f3a4..dc01be08676e 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include diff --git a/rust/helpers.c b/rust/helpers.c index 11965b1e2f4e..1b33ed602090 100644 --- a/rust/helpers.c +++ b/rust/helpers.c @@ -408,6 +408,12 @@ void rust_helper___spin_lock_init(spinlock_t *lock, const char *name, } EXPORT_SYMBOL_GPL(rust_helper___spin_lock_init); +unsigned long rust_helper_msecs_to_jiffies(const unsigned int m) +{ + return msecs_to_jiffies(m); +} +EXPORT_SYMBOL_GPL(rust_helper_msecs_to_jiffies); + #ifdef CONFIG_DMA_SHARED_BUFFER void rust_helper_dma_fence_get(struct dma_fence *fence) diff --git a/rust/kernel/drm/mod.rs b/rust/kernel/drm/mod.rs index dae98826edfd..3ddf7712aab3 100644 --- a/rust/kernel/drm/mod.rs +++ b/rust/kernel/drm/mod.rs @@ -8,4 +8,6 @@ pub mod file; pub mod gem; pub mod ioctl; pub mod mm; +#[cfg(CONFIG_RUST_DRM_SCHED)] +pub mod sched; pub mod syncobj; diff --git a/rust/kernel/drm/sched.rs b/rust/kernel/drm/sched.rs new file mode 100644 index 000000000000..a5275cc16179 --- /dev/null +++ b/rust/kernel/drm/sched.rs @@ -0,0 +1,358 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM Scheduler +//! +//! C header: [`include/linux/drm/gpu_scheduler.h`](../../../../include/linux/drm/gpu_scheduler.h) + +use crate::{ + bindings, device, + dma_fence::*, + error::{to_result, Result}, + prelude::*, + sync::{Arc, UniqueArc}, +}; +use alloc::boxed::Box; +use core::marker::PhantomData; +use core::mem::MaybeUninit; +use core::ops::{Deref, DerefMut}; +use core::ptr::addr_of_mut; + +/// Scheduler status after timeout recovery +#[repr(u32)] +pub enum Status { + /// Device recovered from the timeout and can execute jobs again + Nominal = bindings::drm_gpu_sched_stat_DRM_GPU_SCHED_STAT_NOMINAL, + /// Device is no longer available + NoDevice = bindings::drm_gpu_sched_stat_DRM_GPU_SCHED_STAT_ENODEV, +} + +/// Scheduler priorities +#[repr(i32)] +pub enum Priority { + /// Low userspace priority + Min = bindings::drm_sched_priority_DRM_SCHED_PRIORITY_MIN, + /// Normal userspace priority + Normal = bindings::drm_sched_priority_DRM_SCHED_PRIORITY_NORMAL, + /// High userspace priority + High = bindings::drm_sched_priority_DRM_SCHED_PRIORITY_HIGH, + /// Kernel priority (highest) + Kernel = bindings::drm_sched_priority_DRM_SCHED_PRIORITY_KERNEL, +} + +/// Trait to be implemented by driver job objects. +pub trait JobImpl: Sized { + /// Called when the scheduler is considering scheduling this job next, to get another Fence + /// for this job to block on. Once it returns None, run() may be called. + fn prepare(_job: &mut Job) -> Option { + None // Equivalent to NULL function pointer + } + + /// Called before job execution to check whether the hardware is free enough to run the job. + /// This can be used to implement more complex hardware resource policies than the hw_submission + /// limit. + fn can_run(_job: &mut Job) -> bool { + true + } + + /// Called to execute the job once all of the dependencies have been resolved. This may be + /// called multiple times, if timed_out() has happened and drm_sched_job_recovery() decides + /// to try it again. + fn run(job: &mut Job) -> Result>; + + /// Called when a job has taken too long to execute, to trigger GPU recovery. + /// + /// This method is called in a workqueue context. + fn timed_out(job: &mut Job) -> Status; +} + +unsafe extern "C" fn prepare_job_cb( + sched_job: *mut bindings::drm_sched_job, + _s_entity: *mut bindings::drm_sched_entity, +) -> *mut bindings::dma_fence { + // SAFETY: All of our jobs are Job. + let p = crate::container_of!(sched_job, Job, job) as *mut Job; + + match T::prepare(unsafe { &mut *p }) { + None => core::ptr::null_mut(), + Some(fence) => fence.into_raw(), + } +} + +unsafe extern "C" fn run_job_cb( + sched_job: *mut bindings::drm_sched_job, +) -> *mut bindings::dma_fence { + // SAFETY: All of our jobs are Job. + let p = crate::container_of!(sched_job, Job, job) as *mut Job; + + match T::run(unsafe { &mut *p }) { + Err(e) => e.to_ptr(), + Ok(None) => core::ptr::null_mut(), + Ok(Some(fence)) => fence.into_raw(), + } +} + +unsafe extern "C" fn can_run_job_cb(sched_job: *mut bindings::drm_sched_job) -> bool { + // SAFETY: All of our jobs are Job. + let p = crate::container_of!(sched_job, Job, job) as *mut Job; + + T::can_run(unsafe { &mut *p }) +} + +unsafe extern "C" fn timedout_job_cb( + sched_job: *mut bindings::drm_sched_job, +) -> bindings::drm_gpu_sched_stat { + // SAFETY: All of our jobs are Job. + let p = crate::container_of!(sched_job, Job, job) as *mut Job; + + T::timed_out(unsafe { &mut *p }) as bindings::drm_gpu_sched_stat +} + +unsafe extern "C" fn free_job_cb(sched_job: *mut bindings::drm_sched_job) { + // SAFETY: All of our jobs are Job. + let p = crate::container_of!(sched_job, Job, job) as *mut Job; + + // Convert the job back to a Box and drop it + // SAFETY: All of our Jobs are created inside a box. + unsafe { Box::from_raw(p) }; +} + +/// A DRM scheduler job. +pub struct Job { + job: bindings::drm_sched_job, + inner: T, +} + +impl Deref for Job { + type Target = T; + + fn deref(&self) -> &Self::Target { + &self.inner + } +} + +impl DerefMut for Job { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.inner + } +} + +impl Drop for Job { + fn drop(&mut self) { + // SAFETY: At this point the job has either been submitted and this is being called from + // `free_job_cb` above, or it hasn't and it is safe to call `drm_sched_job_cleanup`. + unsafe { bindings::drm_sched_job_cleanup(&mut self.job) }; + } +} + +/// A pending DRM scheduler job (not yet armed) +pub struct PendingJob<'a, T: JobImpl>(Box>, PhantomData<&'a T>); + +impl<'a, T: JobImpl> PendingJob<'a, T> { + /// Add a fence as a dependency to the job + pub fn add_dependency(&mut self, fence: Fence) -> Result { + to_result(unsafe { + bindings::drm_sched_job_add_dependency(&mut self.0.job, fence.into_raw()) + }) + } + + /// Arm the job to make it ready for execution + pub fn arm(mut self) -> ArmedJob<'a, T> { + unsafe { bindings::drm_sched_job_arm(&mut self.0.job) }; + ArmedJob(self.0, PhantomData) + } +} + +impl<'a, T: JobImpl> Deref for PendingJob<'a, T> { + type Target = Job; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, T: JobImpl> DerefMut for PendingJob<'a, T> { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// An armed DRM scheduler job (not yet submitted) +pub struct ArmedJob<'a, T: JobImpl>(Box>, PhantomData<&'a T>); + +impl<'a, T: JobImpl> ArmedJob<'a, T> { + /// Returns the job fences + pub fn fences(&self) -> JobFences<'_> { + JobFences(unsafe { &mut *self.0.job.s_fence }) + } + + /// Push the job for execution into the scheduler + pub fn push(self) { + // After this point, the job is submitted and owned by the scheduler + let ptr = match self { + ArmedJob(job, _) => Box::>::into_raw(job), + }; + + // SAFETY: We are passing in ownership of a valid Box raw pointer. + unsafe { bindings::drm_sched_entity_push_job(addr_of_mut!((*ptr).job)) }; + } +} +impl<'a, T: JobImpl> Deref for ArmedJob<'a, T> { + type Target = Job; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, T: JobImpl> DerefMut for ArmedJob<'a, T> { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// Reference to the bundle of fences attached to a DRM scheduler job +pub struct JobFences<'a>(&'a mut bindings::drm_sched_fence); + +impl<'a> JobFences<'a> { + /// Returns a new reference to the job scheduled fence. + pub fn scheduled(&mut self) -> Fence { + unsafe { Fence::get_raw(&mut self.0.scheduled) } + } + + /// Returns a new reference to the job finished fence. + pub fn finished(&mut self) -> Fence { + unsafe { Fence::get_raw(&mut self.0.finished) } + } +} + +struct EntityInner { + entity: bindings::drm_sched_entity, + // TODO: Allow users to share guilty flag between entities + sched: Arc>, + guilty: bindings::atomic_t, + _p: PhantomData, +} + +impl Drop for EntityInner { + fn drop(&mut self) { + // SAFETY: The EntityInner is initialized. This will cancel/free all jobs. + unsafe { bindings::drm_sched_entity_destroy(&mut self.entity) }; + } +} + +// SAFETY: TODO +unsafe impl Sync for EntityInner {} +unsafe impl Send for EntityInner {} + +/// A DRM scheduler entity. +pub struct Entity(Pin>>); + +impl Entity { + /// Create a new scheduler entity. + pub fn new(sched: &Scheduler, priority: Priority) -> Result { + let mut entity: Box>> = Box::try_new_zeroed()?; + + let mut sched_ptr = &sched.0.sched as *const _ as *mut _; + + // SAFETY: The Box is allocated above and valid. + unsafe { + bindings::drm_sched_entity_init( + addr_of_mut!((*entity.as_mut_ptr()).entity), + priority as _, + &mut sched_ptr, + 1, + addr_of_mut!((*entity.as_mut_ptr()).guilty), + ) + }; + + // SAFETY: The Box is allocated above and valid. + unsafe { addr_of_mut!((*entity.as_mut_ptr()).sched).write(sched.0.clone()) }; + + // SAFETY: entity is now initialized. + Ok(Self(Pin::from(unsafe { entity.assume_init() }))) + } + + /// Create a new job on this entity. + /// + /// The entity must outlive the pending job until it transitions into the submitted state, + /// after which the scheduler owns it. + pub fn new_job(&self, inner: T) -> Result> { + let mut job: Box>> = Box::try_new_zeroed()?; + + // SAFETY: We hold a reference to the entity (which is a valid pointer), + // and the job object was just allocated above. + to_result(unsafe { + bindings::drm_sched_job_init( + addr_of_mut!((*job.as_mut_ptr()).job), + &self.0.as_ref().get_ref().entity as *const _ as *mut _, + core::ptr::null_mut(), + ) + })?; + + // SAFETY: The Box pointer is valid, and this initializes the inner member. + unsafe { addr_of_mut!((*job.as_mut_ptr()).inner).write(inner) }; + + // SAFETY: All fields of the Job are now initialized. + Ok(PendingJob(unsafe { job.assume_init() }, PhantomData)) + } +} + +/// DRM scheduler inner data +pub struct SchedulerInner { + sched: bindings::drm_gpu_scheduler, + _p: PhantomData, +} + +impl Drop for SchedulerInner { + fn drop(&mut self) { + // SAFETY: The scheduler is valid. This assumes drm_sched_fini() will take care of + // freeing all in-progress jobs. + unsafe { bindings::drm_sched_fini(&mut self.sched) }; + } +} + +// SAFETY: TODO +unsafe impl Sync for SchedulerInner {} +unsafe impl Send for SchedulerInner {} + +/// A DRM Scheduler +pub struct Scheduler(Arc>); + +impl Scheduler { + const OPS: bindings::drm_sched_backend_ops = bindings::drm_sched_backend_ops { + prepare_job: Some(prepare_job_cb::), + can_run_job: Some(can_run_job_cb::), + run_job: Some(run_job_cb::), + timedout_job: Some(timedout_job_cb::), + free_job: Some(free_job_cb::), + }; + /// Creates a new DRM Scheduler object + // TODO: Shared timeout workqueues & scores + pub fn new( + device: &impl device::RawDevice, + hw_submission: u32, + hang_limit: u32, + timeout_ms: usize, + name: &'static CStr, + ) -> Result> { + let mut sched: UniqueArc>> = UniqueArc::try_new_uninit()?; + + // SAFETY: The drm_sched pointer is valid and pinned as it was just allocated above. + to_result(unsafe { + bindings::drm_sched_init( + addr_of_mut!((*sched.as_mut_ptr()).sched), + &Self::OPS, + hw_submission, + hang_limit, + bindings::msecs_to_jiffies(timeout_ms.try_into()?).try_into()?, + core::ptr::null_mut(), + core::ptr::null_mut(), + name.as_char_ptr(), + device.raw_device(), + ) + })?; + + // SAFETY: All fields of SchedulerInner are now initialized. + Ok(Scheduler(unsafe { sched.assume_init() }.into())) + } +}