Linaro-mm-sig

linaro-mm-sig@lists.linaro.org

15 participants
3025 discussions

Re: [Linaro-mm-sig] [PATCH v3 2/2] drm: protect drm_master pointers in drm_lease.c

by Daniel Vetter

On Sun, Jun 20, 2021 at 07:03:27PM +0800, Desmond Cheong Zhi Xi wrote: > Currently, direct copies of drm_file->master pointers should be > protected by drm_device.master_mutex when being dereferenced. This is > because drm_file->master is not invariant for the lifetime of > drm_file. If drm_file is not the creator of master, then > drm_file->is_master is false, and a call to drm_setmaster_ioctl will > invoke drm_new_set_master, which then allocates a new master for > drm_file and puts the old master. > > Thus, without holding drm_device.master_mutex, the old value of > drm_file->master could be freed while it is being used by another > concurrent process. > > In drm_lease.c, there are multiple instances where drm_file->master is > accessed and dereferenced while drm_device.master_mutex is not > held. This makes drm_lease.c vulnerable to use-after-free bugs. > > We address this issue as follows: > > 1. Clarify in the kerneldoc that drm_file->master is protected by > drm_device.master_mutex. > > 2. Add a new drm_file_get_master() function that calls drm_master_get > on drm_file->master while holding on to drm_device.master_mutex. Since > drm_master_get increments the reference count of master, this > prevents master from being freed until we unreference it with > drm_master_put. > > 3. In each case where drm_file->master is directly accessed and > eventually dereferenced in drm_lease.c, we wrap the access in a call > to the new drm_file_get_master function, then unreference the master > pointer once we are done using it. > > Reported-by: Daniel Vetter <daniel.vetter(a)ffwll.ch> > Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx(a)gmail.com> I think this approach looks much clearer than the previous. I've found a few smaller things below still. I think at least ... Cheers, Daniel > --- > drivers/gpu/drm/drm_auth.c | 22 ++++++++++++++ > drivers/gpu/drm/drm_lease.c | 57 ++++++++++++++++++++++++++----------- > include/drm/drm_auth.h | 1 + > include/drm/drm_file.h | 15 ++++++++-- > 4 files changed, 75 insertions(+), 20 deletions(-) > > diff --git a/drivers/gpu/drm/drm_auth.c b/drivers/gpu/drm/drm_auth.c > index 86d4b72e95cb..0c64a77c67a6 100644 > --- a/drivers/gpu/drm/drm_auth.c > +++ b/drivers/gpu/drm/drm_auth.c > @@ -384,6 +384,28 @@ struct drm_master *drm_master_get(struct drm_master *master) > } > EXPORT_SYMBOL(drm_master_get); > > +/** > + * drm_file_get_master - reference @file_priv->master > + * @file_priv: DRM file private > + * > + * Increments the reference count of @file_priv->master and returns Does this format correctly? I'd go with "&drm_file.master of @file_priv". > + * @file_priv->master. > + * > + * Master pointers returned from this function should be unreferenced using > + * drm_master_put(). > + */ > +struct drm_master *drm_file_get_master(struct drm_file *file_priv) > +{ > + struct drm_master *master; > + > + mutex_lock(&file_priv->master->dev->master_mutex); > + master = drm_master_get(file_priv->master); > + mutex_unlock(&file_priv->master->dev->master_mutex); > + > + return master; > +} > +EXPORT_SYMBOL(drm_file_get_master); > + > static void drm_master_destroy(struct kref *kref) > { > struct drm_master *master = container_of(kref, struct drm_master, refcount); > diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c > index da4f085fc09e..65eab82f8acc 100644 > --- a/drivers/gpu/drm/drm_lease.c > +++ b/drivers/gpu/drm/drm_lease.c > @@ -107,10 +107,17 @@ static bool _drm_has_leased(struct drm_master *master, int id) > */ > bool _drm_lease_held(struct drm_file *file_priv, int id) > { > + bool ret; > + struct drm_master *master; > + > if (!file_priv || !file_priv->master) So here we still have a ->master access outside of the locked code section. I think the best fix for that would be to move the NULL check into drm_file_get_master (where we grab the lock already anyway), and update the kerneldoc to state that it might return NULL. Same with all the checks for ->master below. > return true; > > - return _drm_lease_held_master(file_priv->master, id); > + master = drm_file_get_master(file_priv); > + ret = _drm_lease_held_master(master, id); > + drm_master_put(&master); > + > + return ret; > } > > /** > @@ -132,10 +139,11 @@ bool drm_lease_held(struct drm_file *file_priv, int id) > if (!file_priv || !file_priv->master || !file_priv->master->lessor) > return true; master->lessor dereferenced outside the lock or without holding a reference. > > - master = file_priv->master; > + master = drm_file_get_master(file_priv); > mutex_lock(&master->dev->mode_config.idr_mutex); > ret = _drm_lease_held_master(master, id); > mutex_unlock(&master->dev->mode_config.idr_mutex); > + drm_master_put(&master); > return ret; > } > > @@ -158,7 +166,7 @@ uint32_t drm_lease_filter_crtcs(struct drm_file *file_priv, uint32_t crtcs_in) > if (!file_priv || !file_priv->master || !file_priv->master->lessor) > return crtcs_in; Same here. > > - master = file_priv->master; > + master = drm_file_get_master(file_priv); > dev = master->dev; > > count_in = count_out = 0; > @@ -177,6 +185,7 @@ uint32_t drm_lease_filter_crtcs(struct drm_file *file_priv, uint32_t crtcs_in) > count_in++; > } > mutex_unlock(&master->dev->mode_config.idr_mutex); > + drm_master_put(&master); > return crtcs_out; > } > > @@ -490,7 +499,7 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, > size_t object_count; > int ret = 0; > struct idr leases; > - struct drm_master *lessor = lessor_priv->master; > + struct drm_master *lessor; > struct drm_master *lessee = NULL; > struct file *lessee_file = NULL; > struct file *lessor_file = lessor_priv->filp; > @@ -502,12 +511,6 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > return -EOPNOTSUPP; > > - /* Do not allow sub-leases */ > - if (lessor->lessor) { > - DRM_DEBUG_LEASE("recursive leasing not allowed\n"); > - return -EINVAL; > - } > - > /* need some objects */ > if (cl->object_count == 0) { > DRM_DEBUG_LEASE("no objects in lease\n"); > @@ -519,12 +522,22 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, > return -EINVAL; > } > > + lessor = drm_file_get_master(lessor_priv); > + /* Do not allow sub-leases */ > + if (lessor->lessor) { Here we check after grabbing the reference, so looks correct. > + DRM_DEBUG_LEASE("recursive leasing not allowed\n"); > + ret = -EINVAL; > + goto out_lessor; > + } > + > object_count = cl->object_count; > > object_ids = memdup_user(u64_to_user_ptr(cl->object_ids), > array_size(object_count, sizeof(__u32))); > - if (IS_ERR(object_ids)) > - return PTR_ERR(object_ids); > + if (IS_ERR(object_ids)) { > + ret = PTR_ERR(object_ids); > + goto out_lessor; > + } > > idr_init(&leases); > > @@ -535,14 +548,15 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, > if (ret) { > DRM_DEBUG_LEASE("lease object lookup failed: %i\n", ret); > idr_destroy(&leases); > - return ret; > + goto out_lessor; > } > > /* Allocate a file descriptor for the lease */ > fd = get_unused_fd_flags(cl->flags & (O_CLOEXEC | O_NONBLOCK)); > if (fd < 0) { > idr_destroy(&leases); > - return fd; > + ret = fd; > + goto out_lessor; > } > > DRM_DEBUG_LEASE("Creating lease\n"); > @@ -578,6 +592,7 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, > /* Hook up the fd */ > fd_install(fd, lessee_file); > > + drm_master_put(&lessor); > DRM_DEBUG_LEASE("drm_mode_create_lease_ioctl succeeded\n"); > return 0; > > @@ -587,6 +602,8 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, > out_leases: > put_unused_fd(fd); > > +out_lessor: > + drm_master_put(&lessor); > DRM_DEBUG_LEASE("drm_mode_create_lease_ioctl failed: %d\n", ret); > return ret; > } > @@ -609,7 +626,7 @@ int drm_mode_list_lessees_ioctl(struct drm_device *dev, > struct drm_mode_list_lessees *arg = data; > __u32 __user *lessee_ids = (__u32 __user *) (uintptr_t) (arg->lessees_ptr); > __u32 count_lessees = arg->count_lessees; > - struct drm_master *lessor = lessor_priv->master, *lessee; > + struct drm_master *lessor, *lessee; > int count; > int ret = 0; > > @@ -620,6 +637,7 @@ int drm_mode_list_lessees_ioctl(struct drm_device *dev, > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > return -EOPNOTSUPP; > > + lessor = drm_file_get_master(lessor_priv); > DRM_DEBUG_LEASE("List lessees for %d\n", lessor->lessee_id); > > mutex_lock(&dev->mode_config.idr_mutex); > @@ -643,6 +661,7 @@ int drm_mode_list_lessees_ioctl(struct drm_device *dev, > arg->count_lessees = count; > > mutex_unlock(&dev->mode_config.idr_mutex); > + drm_master_put(&lessor); > > return ret; > } > @@ -662,7 +681,7 @@ int drm_mode_get_lease_ioctl(struct drm_device *dev, > struct drm_mode_get_lease *arg = data; > __u32 __user *object_ids = (__u32 __user *) (uintptr_t) (arg->objects_ptr); > __u32 count_objects = arg->count_objects; > - struct drm_master *lessee = lessee_priv->master; > + struct drm_master *lessee; > struct idr *object_idr; > int count; > void *entry; > @@ -676,6 +695,7 @@ int drm_mode_get_lease_ioctl(struct drm_device *dev, > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > return -EOPNOTSUPP; > > + lessee = drm_file_get_master(lessee_priv); > DRM_DEBUG_LEASE("get lease for %d\n", lessee->lessee_id); > > mutex_lock(&dev->mode_config.idr_mutex); > @@ -703,6 +723,7 @@ int drm_mode_get_lease_ioctl(struct drm_device *dev, > arg->count_objects = count; > > mutex_unlock(&dev->mode_config.idr_mutex); > + drm_master_put(&lessee); > > return ret; > } > @@ -721,7 +742,7 @@ int drm_mode_revoke_lease_ioctl(struct drm_device *dev, > void *data, struct drm_file *lessor_priv) > { > struct drm_mode_revoke_lease *arg = data; > - struct drm_master *lessor = lessor_priv->master; > + struct drm_master *lessor; > struct drm_master *lessee; > int ret = 0; > > @@ -731,6 +752,7 @@ int drm_mode_revoke_lease_ioctl(struct drm_device *dev, > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > return -EOPNOTSUPP; > > + lessor = drm_file_get_master(lessor_priv); > mutex_lock(&dev->mode_config.idr_mutex); > > lessee = _drm_find_lessee(lessor, arg->lessee_id); > @@ -751,6 +773,7 @@ int drm_mode_revoke_lease_ioctl(struct drm_device *dev, > > fail: > mutex_unlock(&dev->mode_config.idr_mutex); > + drm_master_put(&lessor); > > return ret; > } > diff --git a/include/drm/drm_auth.h b/include/drm/drm_auth.h > index 6bf8b2b78991..f99d3417f304 100644 > --- a/include/drm/drm_auth.h > +++ b/include/drm/drm_auth.h > @@ -107,6 +107,7 @@ struct drm_master { > }; > > struct drm_master *drm_master_get(struct drm_master *master); > +struct drm_master *drm_file_get_master(struct drm_file *file_priv); > void drm_master_put(struct drm_master **master); > bool drm_is_current_master(struct drm_file *fpriv); > > diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h > index b81b3bfb08c8..e9931fca4ab7 100644 > --- a/include/drm/drm_file.h > +++ b/include/drm/drm_file.h > @@ -226,9 +226,18 @@ struct drm_file { > /** > * @master: > * > - * Master this node is currently associated with. Only relevant if > - * drm_is_primary_client() returns true. Note that this only > - * matches &drm_device.master if the master is the currently active one. > + * Master this node is currently associated with. Protected by struct > + * &drm_device.master_mutex. > + * > + * Only relevant if drm_is_primary_client() returns true. Note that > + * this only matches &drm_device.master if the master is the currently > + * active one. > + * > + * When obtaining a copy of this pointer, it is recommended to either > + * hold struct &drm_device.master_mutex for the duration of the > + * pointer's use, or to use drm_file_get_master() if struct > + * &drm_device.master_mutex is not currently held and there is no other > + * need to hold it. This prevents @master from being freed during use. > * > * See also @authentication and @is_master and the :ref:`section on > * primary nodes and authentication <drm_primary_node>`. > -- > 2.25.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch

4 years, 2 months

Fixing problems around shared fences and RCU in DMA-buf

by Christian König

Hi everyone and especially Daniel, this is the revised patch set to fix and rework dma_buf_poll(). The new code should avoid problems with RCU and also now correctly waits for all fences in the resv object. The rest of the series is then the well known change to dma_resv_test_signaled(), nouveau and now new also msm. Then last are two patches which drop the workarounds from amdgpu, but those can wait till the next cycle. I think it would be rather good if the have at least to change to dma_buf_poll() pushed in this merge window and maybe even CC stable since this looks really broken to me. Please review, test and/or comment. Thanks, Christian.

4 years, 2 months

Introduce fence iterators to abstract dma_resv RCU handling

by Christian König

Hi guys, during the recent discussion about SLAB_TYPESAFE_BY_RCU, dma_fence_get_rcu and dma_fence_get_rcu_safe we found that the RCU handling for dma_resv objects was implemented multiple times. Unfortunately a lot of those implementations get the rather complicated dance with RCU and the sequence number handling wrong. So this patch set aims to audit and unify this by providing an iterator which automatically restarts when a modification to the dma_resv object is detected. The result is pretty impressive I think since this not only mean that we got rid of all those incorrect dma_fence_get_rcu() cases, but also reduce the overall loc count quite a bit. Please review and/or comment. Cheers, Christian.

4 years, 2 months

[PATCH v6] dmabuf: Add the capability to expose DMA-BUF stats in sysfs

by Hridya Valsaraju

Overview ======== The patch adds DMA-BUF statistics to /sys/kernel/dmabuf/buffers. It allows statistics to be enabled for each DMA-BUF in sysfs by enabling the config CONFIG_DMABUF_SYSFS_STATS. The following stats will be exposed by the interface: /sys/kernel/dmabuf/buffers/<inode_number>/exporter_name /sys/kernel/dmabuf/buffers/<inode_number>/size /sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attach_uid>/device /sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attach_uid>/map_counter The inode_number is unique for each DMA-BUF and was added earlier [1] in order to allow userspace to track DMA-BUF usage across different processes. Use Cases ========= The interface provides a way to gather DMA-BUF per-buffer statistics from production devices. These statistics will be used to derive DMA-BUF per-exporter stats and per-device usage stats for Android Bug reports. The corresponding userspace changes can be found at [2]. Telemetry tools will also capture this information(along with other memory metrics) periodically as well as on important events like a foreground app kill (which might have been triggered by Low Memory Killer). It will also contribute to provide a snapshot of the system memory usage on other events such as OOM kills and Application Not Responding events. Background ========== Currently, there are two existing interfaces that provide information about DMA-BUFs. 1) /sys/kernel/debug/dma_buf/bufinfo debugfs is however unsuitable to be mounted in production systems and cannot be considered as an alternative to the sysfs interface being proposed. 2) proc/<pid>/fdinfo/<fd> The proc/<pid>/fdinfo/<fd> files expose information about DMA-BUF fds. However, the existing procfs interfaces can only provide information about the buffers for which processes hold fds or have the buffers mmapped into their address space. Since the procfs interfaces alone cannot provide a full picture of all DMA-BUFs in the system, there is the need for an alternate interface to provide this information on production systems. The patch contains the following major improvements over v1: 1) Each attachment is represented by its own directory to allow creating a symlink to the importing device and to also provide room for future expansion. 2) The number of distinct mappings of each attachment is exposed in a separate file. 3) The per-buffer statistics are now in /sys/kernel/dmabuf/buffers inorder to make the interface expandable in future. All of the improvements above are based on suggestions/feedback from Daniel Vetter and Christian König. A shell script that can be run on a classic Linux environment to read out the DMA-BUF statistics can be found at [3](suggested by John Stultz). [1]: https://lore.kernel.org/patchwork/patch/1088791/ [2]: https://android-review.googlesource.com/q/topic:%22dmabuf-sysfs%22+(status:… [3]: https://android-review.googlesource.com/c/platform/system/memory/libmeminfo… Reviewed-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Hridya Valsaraju <hridya(a)google.com> Reported-by: kernel test robot <lkp(a)intel.com> --- Hello Daniel, I have added the documentation as a DOC: overview section in the dma-buf-sysfs-stats.c file as per your suggestion. Please do take a look when you get a chance. Thanks in advance! Regards, Hridya Change in v6: -Moved documentation content from Documentation/driver-api/dma-buf.rst to drivers/dma-buf/dma-buf-sysfs-stats.c as a DOC section and linked to it from Documentation/driver-api/dma-buf.rst. Based on feedback from Daniel Vetter. Change in v5: -Added a section on DMA-BUF statistics to Documentation/driver-api/dma-buf.rst. Organized the commit message to clearly state the need for the new interface and provide the background on why the existing means of DMA-BUF accounting will not suffice. Based on feedback from Daniel Vetter. Changes in v4: -Suppress uevents from kset creation to avoid waking up uevent listeners on DMA-BUF export/release. Changes in v3: -Fix a warning reported by the kernel test robot. Changes in v2: -Move statistics to /sys/kernel/dmabuf/buffers in oder to allow addition of other DMA-BUF-related sysfs stats in future. Based on feedback from Daniel Vetter. -Each attachment has its own directory to represent attached devices as symlinks and to introduce map_count as a separate file. Based on feedback from Daniel Vetter and Christian König. Thank you both! -Commit messages updated to point to userspace code in AOSP that will read the DMA-BUF sysfs stats. .../ABI/testing/sysfs-kernel-dmabuf-buffers | 52 +++ Documentation/driver-api/dma-buf.rst | 5 + drivers/dma-buf/Kconfig | 11 + drivers/dma-buf/Makefile | 1 + drivers/dma-buf/dma-buf-sysfs-stats.c | 337 ++++++++++++++++++ drivers/dma-buf/dma-buf-sysfs-stats.h | 62 ++++ drivers/dma-buf/dma-buf.c | 37 ++ include/linux/dma-buf.h | 20 ++ 8 files changed, 525 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-kernel-dmabuf-buffers create mode 100644 drivers/dma-buf/dma-buf-sysfs-stats.c create mode 100644 drivers/dma-buf/dma-buf-sysfs-stats.h diff --git a/Documentation/ABI/testing/sysfs-kernel-dmabuf-buffers b/Documentation/ABI/testing/sysfs-kernel-dmabuf-buffers new file mode 100644 index 000000000000..a243984ed420 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-dmabuf-buffers @@ -0,0 +1,52 @@ +What: /sys/kernel/dmabuf/buffers +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: The /sys/kernel/dmabuf/buffers directory contains a + snapshot of the internal state of every DMA-BUF. + /sys/kernel/dmabuf/buffers/<inode_number> will contain the + statistics for the DMA-BUF with the unique inode number + <inode_number> +Users: kernel memory tuning/debugging tools + +What: /sys/kernel/dmabuf/buffers/<inode_number>/exporter_name +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: This file is read-only and contains the name of the exporter of + the DMA-BUF. + +What: /sys/kernel/dmabuf/buffers/<inode_number>/size +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: This file is read-only and specifies the size of the DMA-BUF in + bytes. + +What: /sys/kernel/dmabuf/buffers/<inode_number>/attachments +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: This directory will contain subdirectories representing every + attachment of the DMA-BUF. + +What: /sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attachment_uid> +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: This directory will contain information on the attached device + and the number of current distinct device mappings. + +What: /sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attachment_uid>/device +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: This file is read-only and is a symlink to the attached device's + sysfs entry. + +What: /sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attachment_uid>/map_counter +Date: May 2021 +KernelVersion: v5.13 +Contact: Hridya Valsaraju <hridya(a)google.com> +Description: This file is read-only and contains a map_counter indicating the + number of distinct device mappings of the attachment. diff --git a/Documentation/driver-api/dma-buf.rst b/Documentation/driver-api/dma-buf.rst index 7f37ec30d9fd..d47a429dc549 100644 --- a/Documentation/driver-api/dma-buf.rst +++ b/Documentation/driver-api/dma-buf.rst @@ -106,6 +106,11 @@ Implicit Fence Poll Support .. kernel-doc:: drivers/dma-buf/dma-buf.c :doc: implicit fence polling +DMA-BUF statistics +~~~~~~~~~~~~~~~~~~ +.. kernel-doc:: drivers/dma-buf/dma-buf-sysfs-stats.c + :doc: overview + Kernel Functions and Structures Reference ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig index 4e16c71c24b7..9561e3d2d428 100644 --- a/drivers/dma-buf/Kconfig +++ b/drivers/dma-buf/Kconfig @@ -72,6 +72,17 @@ menuconfig DMABUF_HEAPS allows userspace to allocate dma-bufs that can be shared between drivers. +menuconfig DMABUF_SYSFS_STATS + bool "DMA-BUF sysfs statistics" + select DMA_SHARED_BUFFER + help + Choose this option to enable DMA-BUF sysfs statistics + in location /sys/kernel/dmabuf/buffers. + + /sys/kernel/dmabuf/buffers/<inode_number> will contain + statistics for the DMA-BUF with the unique inode number + <inode_number>. + source "drivers/dma-buf/heaps/Kconfig" endmenu diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile index 995e05f609ff..40d81f23cacf 100644 --- a/drivers/dma-buf/Makefile +++ b/drivers/dma-buf/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_DMABUF_HEAPS) += heaps/ obj-$(CONFIG_SYNC_FILE) += sync_file.o obj-$(CONFIG_SW_SYNC) += sw_sync.o sync_debug.o obj-$(CONFIG_UDMABUF) += udmabuf.o +obj-$(CONFIG_DMABUF_SYSFS_STATS) += dma-buf-sysfs-stats.o dmabuf_selftests-y := \ selftest.o \ diff --git a/drivers/dma-buf/dma-buf-sysfs-stats.c b/drivers/dma-buf/dma-buf-sysfs-stats.c new file mode 100644 index 000000000000..a2638e84199c --- /dev/null +++ b/drivers/dma-buf/dma-buf-sysfs-stats.c @@ -0,0 +1,337 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * DMA-BUF sysfs statistics. + * + * Copyright (C) 2021 Google LLC. + */ + +#include <linux/dma-buf.h> +#include <linux/dma-resv.h> +#include <linux/kobject.h> +#include <linux/printk.h> +#include <linux/slab.h> +#include <linux/sysfs.h> + +#include "dma-buf-sysfs-stats.h" + +#define to_dma_buf_entry_from_kobj(x) container_of(x, struct dma_buf_sysfs_entry, kobj) + +/** + * DOC: overview + * + * ``/sys/kernel/debug/dma_buf/bufinfo`` provides an overview of every DMA-BUF + * in the system. However, since debugfs is not safe to be mounted in + * production, procfs and sysfs can be used to gather DMA-BUF statistics on + * production systems. + * + * The ``/proc/<pid>/fdinfo/<fd>`` files in procfs can be used to gather + * information about DMA-BUF fds. Detailed documentation about the interface + * is present in Documentation/filesystems/proc.rst. + * + * Unfortunately, the existing procfs interfaces can only provide information + * about the DMA-BUFs for which processes hold fds or have the buffers mmapped + * into their address space. This necessitated the creation of the DMA-BUF sysfs + * statistics interface to provide per-buffer information on production systems. + * + * The interface at ``/sys/kernel/dma-buf/buffers`` exposes information about + * every DMA-BUF when ``CONFIG_DMABUF_SYSFS_STATS`` is enabled. + * + * The following stats are exposed by the interface: + * + * * ``/sys/kernel/dmabuf/buffers/<inode_number>/exporter_name`` + * * ``/sys/kernel/dmabuf/buffers/<inode_number>/size`` + * * ``/sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attach_uid>/device`` + * * ``/sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attach_uid>/map_counter`` + * + * The information in the interface can also be used to derive per-exporter and + * per-device usage statistics. The data from the interface can be gathered + * on error conditions or other important events to provide a snapshot of + * DMA-BUF usage. It can also be collected periodically by telemetry to monitor + * various metrics. + * + * Detailed documentation about the interface is present in + * Documentation/ABI/testing/sysfs-kernel-dmabuf-buffers. + */ + +struct dma_buf_stats_attribute { + struct attribute attr; + ssize_t (*show)(struct dma_buf *dmabuf, + struct dma_buf_stats_attribute *attr, char *buf); +}; +#define to_dma_buf_stats_attr(x) container_of(x, struct dma_buf_stats_attribute, attr) + +static ssize_t dma_buf_stats_attribute_show(struct kobject *kobj, + struct attribute *attr, + char *buf) +{ + struct dma_buf_stats_attribute *attribute; + struct dma_buf_sysfs_entry *sysfs_entry; + struct dma_buf *dmabuf; + + attribute = to_dma_buf_stats_attr(attr); + sysfs_entry = to_dma_buf_entry_from_kobj(kobj); + dmabuf = sysfs_entry->dmabuf; + + if (!dmabuf || !attribute->show) + return -EIO; + + return attribute->show(dmabuf, attribute, buf); +} + +static const struct sysfs_ops dma_buf_stats_sysfs_ops = { + .show = dma_buf_stats_attribute_show, +}; + +static ssize_t exporter_name_show(struct dma_buf *dmabuf, + struct dma_buf_stats_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", dmabuf->exp_name); +} + +static ssize_t size_show(struct dma_buf *dmabuf, + struct dma_buf_stats_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%zu\n", dmabuf->size); +} + +static struct dma_buf_stats_attribute exporter_name_attribute = + __ATTR_RO(exporter_name); +static struct dma_buf_stats_attribute size_attribute = __ATTR_RO(size); + +static struct attribute *dma_buf_stats_default_attrs[] = { + &exporter_name_attribute.attr, + &size_attribute.attr, + NULL, +}; +ATTRIBUTE_GROUPS(dma_buf_stats_default); + +static void dma_buf_sysfs_release(struct kobject *kobj) +{ + struct dma_buf_sysfs_entry *sysfs_entry; + + sysfs_entry = to_dma_buf_entry_from_kobj(kobj); + kfree(sysfs_entry); +} + +static struct kobj_type dma_buf_ktype = { + .sysfs_ops = &dma_buf_stats_sysfs_ops, + .release = dma_buf_sysfs_release, + .default_groups = dma_buf_stats_default_groups, +}; + +#define to_dma_buf_attach_entry_from_kobj(x) container_of(x, struct dma_buf_attach_sysfs_entry, kobj) + +struct dma_buf_attach_stats_attribute { + struct attribute attr; + ssize_t (*show)(struct dma_buf_attach_sysfs_entry *sysfs_entry, + struct dma_buf_attach_stats_attribute *attr, char *buf); +}; +#define to_dma_buf_attach_stats_attr(x) container_of(x, struct dma_buf_attach_stats_attribute, attr) + +static ssize_t dma_buf_attach_stats_attribute_show(struct kobject *kobj, + struct attribute *attr, + char *buf) +{ + struct dma_buf_attach_stats_attribute *attribute; + struct dma_buf_attach_sysfs_entry *sysfs_entry; + + attribute = to_dma_buf_attach_stats_attr(attr); + sysfs_entry = to_dma_buf_attach_entry_from_kobj(kobj); + + if (!attribute->show) + return -EIO; + + return attribute->show(sysfs_entry, attribute, buf); +} + +static const struct sysfs_ops dma_buf_attach_stats_sysfs_ops = { + .show = dma_buf_attach_stats_attribute_show, +}; + +static ssize_t map_counter_show(struct dma_buf_attach_sysfs_entry *sysfs_entry, + struct dma_buf_attach_stats_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%u\n", sysfs_entry->map_counter); +} + +static struct dma_buf_attach_stats_attribute map_counter_attribute = + __ATTR_RO(map_counter); + +static struct attribute *dma_buf_attach_stats_default_attrs[] = { + &map_counter_attribute.attr, + NULL, +}; +ATTRIBUTE_GROUPS(dma_buf_attach_stats_default); + +static void dma_buf_attach_sysfs_release(struct kobject *kobj) +{ + struct dma_buf_attach_sysfs_entry *sysfs_entry; + + sysfs_entry = to_dma_buf_attach_entry_from_kobj(kobj); + kfree(sysfs_entry); +} + +static struct kobj_type dma_buf_attach_ktype = { + .sysfs_ops = &dma_buf_attach_stats_sysfs_ops, + .release = dma_buf_attach_sysfs_release, + .default_groups = dma_buf_attach_stats_default_groups, +}; + +void dma_buf_attach_stats_teardown(struct dma_buf_attachment *attach) +{ + struct dma_buf_attach_sysfs_entry *sysfs_entry; + + sysfs_entry = attach->sysfs_entry; + if (!sysfs_entry) + return; + + sysfs_delete_link(&sysfs_entry->kobj, &attach->dev->kobj, "device"); + + kobject_del(&sysfs_entry->kobj); + kobject_put(&sysfs_entry->kobj); +} + +int dma_buf_attach_stats_setup(struct dma_buf_attachment *attach, + unsigned int uid) +{ + struct dma_buf_attach_sysfs_entry *sysfs_entry; + int ret; + struct dma_buf *dmabuf; + + if (!attach) + return -EINVAL; + + dmabuf = attach->dmabuf; + + sysfs_entry = kzalloc(sizeof(struct dma_buf_attach_sysfs_entry), + GFP_KERNEL); + if (!sysfs_entry) + return -ENOMEM; + + sysfs_entry->kobj.kset = dmabuf->sysfs_entry->attach_stats_kset; + + attach->sysfs_entry = sysfs_entry; + + ret = kobject_init_and_add(&sysfs_entry->kobj, &dma_buf_attach_ktype, + NULL, "%u", uid); + if (ret) + goto kobj_err; + + ret = sysfs_create_link(&sysfs_entry->kobj, &attach->dev->kobj, + "device"); + if (ret) + goto link_err; + + return 0; + +link_err: + kobject_del(&sysfs_entry->kobj); +kobj_err: + kobject_put(&sysfs_entry->kobj); + attach->sysfs_entry = NULL; + + return ret; +} +void dma_buf_stats_teardown(struct dma_buf *dmabuf) +{ + struct dma_buf_sysfs_entry *sysfs_entry; + + sysfs_entry = dmabuf->sysfs_entry; + if (!sysfs_entry) + return; + + kset_unregister(sysfs_entry->attach_stats_kset); + kobject_del(&sysfs_entry->kobj); + kobject_put(&sysfs_entry->kobj); +} + + +/* Statistics files do not need to send uevents. */ +static int dmabuf_sysfs_uevent_filter(struct kset *kset, struct kobject *kobj) +{ + return 0; +} + +static const struct kset_uevent_ops dmabuf_sysfs_no_uevent_ops = { + .filter = dmabuf_sysfs_uevent_filter, +}; + +static struct kset *dma_buf_stats_kset; +static struct kset *dma_buf_per_buffer_stats_kset; +int dma_buf_init_sysfs_statistics(void) +{ + dma_buf_stats_kset = kset_create_and_add("dmabuf", + &dmabuf_sysfs_no_uevent_ops, + kernel_kobj); + if (!dma_buf_stats_kset) + return -ENOMEM; + + dma_buf_per_buffer_stats_kset = kset_create_and_add("buffers", + &dmabuf_sysfs_no_uevent_ops, + &dma_buf_stats_kset->kobj); + if (!dma_buf_per_buffer_stats_kset) { + kset_unregister(dma_buf_stats_kset); + return -ENOMEM; + } + + return 0; +} + +void dma_buf_uninit_sysfs_statistics(void) +{ + kset_unregister(dma_buf_per_buffer_stats_kset); + kset_unregister(dma_buf_stats_kset); +} + +int dma_buf_stats_setup(struct dma_buf *dmabuf) +{ + struct dma_buf_sysfs_entry *sysfs_entry; + int ret; + struct kset *attach_stats_kset; + + if (!dmabuf || !dmabuf->file) + return -EINVAL; + + if (!dmabuf->exp_name) { + pr_err("exporter name must not be empty if stats needed\n"); + return -EINVAL; + } + + sysfs_entry = kzalloc(sizeof(struct dma_buf_sysfs_entry), GFP_KERNEL); + if (!sysfs_entry) + return -ENOMEM; + + sysfs_entry->kobj.kset = dma_buf_per_buffer_stats_kset; + sysfs_entry->dmabuf = dmabuf; + + dmabuf->sysfs_entry = sysfs_entry; + + /* create the directory for buffer stats */ + ret = kobject_init_and_add(&sysfs_entry->kobj, &dma_buf_ktype, NULL, + "%lu", file_inode(dmabuf->file)->i_ino); + if (ret) + goto err_sysfs_dmabuf; + + /* create the directory for attachment stats */ + attach_stats_kset = kset_create_and_add("attachments", + &dmabuf_sysfs_no_uevent_ops, + &sysfs_entry->kobj); + if (!attach_stats_kset) { + ret = -ENOMEM; + goto err_sysfs_attach; + } + + sysfs_entry->attach_stats_kset = attach_stats_kset; + + return 0; + +err_sysfs_attach: + kobject_del(&sysfs_entry->kobj); +err_sysfs_dmabuf: + kobject_put(&sysfs_entry->kobj); + dmabuf->sysfs_entry = NULL; + return ret; +} diff --git a/drivers/dma-buf/dma-buf-sysfs-stats.h b/drivers/dma-buf/dma-buf-sysfs-stats.h new file mode 100644 index 000000000000..5f4703249117 --- /dev/null +++ b/drivers/dma-buf/dma-buf-sysfs-stats.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * DMA-BUF sysfs statistics. + * + * Copyright (C) 2021 Google LLC. + */ + +#ifndef _DMA_BUF_SYSFS_STATS_H +#define _DMA_BUF_SYSFS_STATS_H + +#ifdef CONFIG_DMABUF_SYSFS_STATS + +int dma_buf_init_sysfs_statistics(void); +void dma_buf_uninit_sysfs_statistics(void); + +int dma_buf_stats_setup(struct dma_buf *dmabuf); +int dma_buf_attach_stats_setup(struct dma_buf_attachment *attach, + unsigned int uid); +static inline void dma_buf_update_attachment_map_count(struct dma_buf_attachment *attach, + int delta) +{ + struct dma_buf_attach_sysfs_entry *entry = attach->sysfs_entry; + + entry->map_counter += delta; +} +void dma_buf_stats_teardown(struct dma_buf *dmabuf); +void dma_buf_attach_stats_teardown(struct dma_buf_attachment *attach); +static inline unsigned int dma_buf_update_attach_uid(struct dma_buf *dmabuf) +{ + struct dma_buf_sysfs_entry *entry = dmabuf->sysfs_entry; + + return entry->attachment_uid++; +} +#else + +static inline int dma_buf_init_sysfs_statistics(void) +{ + return 0; +} + +static inline void dma_buf_uninit_sysfs_statistics(void) {} + +static inline int dma_buf_stats_setup(struct dma_buf *dmabuf) +{ + return 0; +} +static inline int dma_buf_attach_stats_setup(struct dma_buf_attachment *attach, + unsigned int uid) +{ + return 0; +} + +static inline void dma_buf_stats_teardown(struct dma_buf *dmabuf) {} +static inline void dma_buf_attach_stats_teardown(struct dma_buf_attachment *attach) {} +static inline void dma_buf_update_attachment_map_count(struct dma_buf_attachment *attach, + int delta) {} +static inline unsigned int dma_buf_update_attach_uid(struct dma_buf *dmabuf) +{ + return 0; +} +#endif +#endif // _DMA_BUF_SYSFS_STATS_H diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index f264b70c383e..184dd7acb1ed 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -29,6 +29,8 @@ #include <uapi/linux/dma-buf.h> #include <uapi/linux/magic.h> +#include "dma-buf-sysfs-stats.h" + static inline int is_dma_buf_file(struct file *); struct dma_buf_list { @@ -79,6 +81,7 @@ static void dma_buf_release(struct dentry *dentry) if (dmabuf->resv == (struct dma_resv *)&dmabuf[1]) dma_resv_fini(dmabuf->resv); + dma_buf_stats_teardown(dmabuf); module_put(dmabuf->owner); kfree(dmabuf->name); kfree(dmabuf); @@ -580,6 +583,10 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) file->f_mode |= FMODE_LSEEK; dmabuf->file = file; + ret = dma_buf_stats_setup(dmabuf); + if (ret) + goto err_sysfs; + mutex_init(&dmabuf->lock); INIT_LIST_HEAD(&dmabuf->attachments); @@ -589,6 +596,14 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) return dmabuf; +err_sysfs: + /* + * Set file->f_path.dentry->d_fsdata to NULL so that when + * dma_buf_release() gets invoked by dentry_ops, it exits + * early before calling the release() dma_buf op. + */ + file->f_path.dentry->d_fsdata = NULL; + fput(file); err_dmabuf: kfree(dmabuf); err_module: @@ -723,6 +738,7 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, { struct dma_buf_attachment *attach; int ret; + unsigned int attach_uid; if (WARN_ON(!dmabuf || !dev)) return ERR_PTR(-EINVAL); @@ -748,8 +764,13 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, } dma_resv_lock(dmabuf->resv, NULL); list_add(&attach->node, &dmabuf->attachments); + attach_uid = dma_buf_update_attach_uid(dmabuf); dma_resv_unlock(dmabuf->resv); + ret = dma_buf_attach_stats_setup(attach, attach_uid); + if (ret) + goto err_sysfs; + /* When either the importer or the exporter can't handle dynamic * mappings we cache the mapping here to avoid issues with the * reservation object lock. @@ -776,6 +797,7 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, dma_resv_unlock(attach->dmabuf->resv); attach->sgt = sgt; attach->dir = DMA_BIDIRECTIONAL; + dma_buf_update_attachment_map_count(attach, 1 /* delta */); } return attach; @@ -792,6 +814,7 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, if (dma_buf_is_dynamic(attach->dmabuf)) dma_resv_unlock(attach->dmabuf->resv); +err_sysfs: dma_buf_detach(dmabuf, attach); return ERR_PTR(ret); } @@ -841,6 +864,7 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) dma_resv_lock(attach->dmabuf->resv, NULL); __unmap_dma_buf(attach, attach->sgt, attach->dir); + dma_buf_update_attachment_map_count(attach, -1 /* delta */); if (dma_buf_is_dynamic(attach->dmabuf)) { dma_buf_unpin(attach); @@ -854,6 +878,7 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) if (dmabuf->ops->detach) dmabuf->ops->detach(dmabuf, attach); + dma_buf_attach_stats_teardown(attach); kfree(attach); } EXPORT_SYMBOL_GPL(dma_buf_detach); @@ -993,6 +1018,9 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, } #endif /* CONFIG_DMA_API_DEBUG */ + if (!IS_ERR(sg_table)) + dma_buf_update_attachment_map_count(attach, 1 /* delta */); + return sg_table; } EXPORT_SYMBOL_GPL(dma_buf_map_attachment); @@ -1030,6 +1058,8 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, if (dma_buf_is_dynamic(attach->dmabuf) && !IS_ENABLED(CONFIG_DMABUF_MOVE_NOTIFY)) dma_buf_unpin(attach); + + dma_buf_update_attachment_map_count(attach, -1 /* delta */); } EXPORT_SYMBOL_GPL(dma_buf_unmap_attachment); @@ -1480,6 +1510,12 @@ static inline void dma_buf_uninit_debugfs(void) static int __init dma_buf_init(void) { + int ret; + + ret = dma_buf_init_sysfs_statistics(); + if (ret) + return ret; + dma_buf_mnt = kern_mount(&dma_buf_fs_type); if (IS_ERR(dma_buf_mnt)) return PTR_ERR(dma_buf_mnt); @@ -1495,5 +1531,6 @@ static void __exit dma_buf_deinit(void) { dma_buf_uninit_debugfs(); kern_unmount(dma_buf_mnt); + dma_buf_uninit_sysfs_statistics(); } __exitcall(dma_buf_deinit); diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index efdc56b9d95f..342585bd6dff 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -295,6 +295,9 @@ struct dma_buf_ops { * @poll: for userspace poll support * @cb_excl: for userspace poll support * @cb_shared: for userspace poll support + * @sysfs_entry: for exposing information about this buffer in sysfs. + * The attachment_uid member of @sysfs_entry is protected by dma_resv lock + * and is incremented on each attach. * * This represents a shared buffer, created by calling dma_buf_export(). The * userspace representation is a normal file descriptor, which can be created by @@ -330,6 +333,15 @@ struct dma_buf { __poll_t active; } cb_excl, cb_shared; +#ifdef CONFIG_DMABUF_SYSFS_STATS + /* for sysfs stats */ + struct dma_buf_sysfs_entry { + struct kobject kobj; + struct dma_buf *dmabuf; + unsigned int attachment_uid; + struct kset *attach_stats_kset; + } *sysfs_entry; +#endif }; /** @@ -379,6 +391,7 @@ struct dma_buf_attach_ops { * @importer_ops: importer operations for this attachment, if provided * dma_buf_map/unmap_attachment() must be called with the dma_resv lock held. * @importer_priv: importer specific attachment data. + * @sysfs_entry: For exposing information about this attachment in sysfs. * * This structure holds the attachment information between the dma_buf buffer * and its user device(s). The list contains one attachment struct per device @@ -399,6 +412,13 @@ struct dma_buf_attachment { const struct dma_buf_attach_ops *importer_ops; void *importer_priv; void *priv; +#ifdef CONFIG_DMABUF_SYSFS_STATS + /* for sysfs stats */ + struct dma_buf_attach_sysfs_entry { + struct kobject kobj; + unsigned int map_counter; + } *sysfs_entry; +#endif }; /** -- 2.32.0.rc1.229.g3e70b5a671-goog

4 years, 3 months

[PATCH -next] drm/nouveau: Remove set but not used variable 'dev'

by Baokun Li

Fixes gcc '-Wunused-but-set-variable' warning: drivers/gpu/drm/nouveau/nouveau_bo.c: In function 'nouveau_ttm_tt_populate': drivers/gpu/drm/nouveau/nouveau_bo.c:1258:17: warning: variable ‘dev’ set but not used [-Wunused-but-set-variable] drivers/gpu/drm/nouveau/nouveau_bo.c: In function 'nouveau_ttm_tt_unpopulate': drivers/gpu/drm/nouveau/nouveau_bo.c:1281:17: warning: variable ‘dev’ set but not used [-Wunused-but-set-variable] It never used since introduction. Signed-off-by: Baokun Li <libaokun1(a)huawei.com> --- drivers/gpu/drm/nouveau/nouveau_bo.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c index 7a2624c0ba4c..51f9a2e6532e 100644 --- a/drivers/gpu/drm/nouveau/nouveau_bo.c +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c @@ -1254,7 +1254,6 @@ nouveau_ttm_tt_populate(struct ttm_device *bdev, { struct ttm_tt *ttm_dma = (void *)ttm; struct nouveau_drm *drm; - struct device *dev; bool slave = !!(ttm->page_flags & TTM_PAGE_FLAG_SG); if (ttm_tt_is_populated(ttm)) @@ -1267,7 +1266,6 @@ nouveau_ttm_tt_populate(struct ttm_device *bdev, } drm = nouveau_bdev(bdev); - dev = drm->dev->dev; return ttm_pool_alloc(&drm->ttm.bdev.pool, ttm, ctx); } @@ -1277,14 +1275,12 @@ nouveau_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) { struct nouveau_drm *drm; - struct device *dev; bool slave = !!(ttm->page_flags & TTM_PAGE_FLAG_SG); if (slave) return; drm = nouveau_bdev(bdev); - dev = drm->dev->dev; return ttm_pool_free(&drm->ttm.bdev.pool, ttm); } -- 2.25.4

4 years, 3 months

Re: [Linaro-mm-sig] [PATCH V2] treewide: Add missing semicolons to __assign_str uses

by Steven Rostedt

On Sat, 12 Jun 2021 08:42:27 -0700 Joe Perches <joe(a)perches.com> wrote: > The __assign_str macro has an unusual ending semicolon but the vast > majority of uses of the macro already have semicolon termination. > > $ git grep -P '\b__assign_str\b' | wc -l > 551 > $ git grep -P '\b__assign_str\b.*;' | wc -l > 480 > > Add semicolons to the __assign_str() uses without semicolon termination > and all the other uses without semicolon termination via additional defines > that are equivalent to __assign_str() with the eventual goal of removing > the semicolon from the __assign_str() macro definition. > > Link: https://lore.kernel.org/lkml/1e068d21106bb6db05b735b4916bb420e6c9842a.camel… FYI, please send new patches as new threads. Otherwise it is likely to be missed. -- Steve

4 years, 3 months

[PATCH -next v2] drm/msm: Use list_move_tail instead of list_del/list_add_tail in msm_gem.c

by Baokun Li

Using list_move_tail() instead of list_del() + list_add_tail() in msm_gem.c. Reported-by: Hulk Robot <hulkci(a)huawei.com> Signed-off-by: Baokun Li <libaokun1(a)huawei.com> --- V1->V2: CC mailist drivers/gpu/drm/msm/msm_gem.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index 1865919368f2..5b7d63d3750a 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -854,8 +854,7 @@ void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu) mutex_lock(&priv->mm_lock); if (msm_obj->evictable) mark_unevictable(msm_obj); - list_del(&msm_obj->mm_list); - list_add_tail(&msm_obj->mm_list, &gpu->active_list); + list_move_tail(&msm_obj->mm_list, &gpu->active_list); mutex_unlock(&priv->mm_lock); } }

4 years, 3 months

[PATCH -next v2] drm/amdgpu: use list_move instead of list_del/list_add in amdgpu_vm.c

by Baokun Li

Using list_move() instead of list_del() + list_add() in amdgpu_vm.c. Reported-by: Hulk Robot <hulkci(a)huawei.com> Signed-off-by: Baokun Li <libaokun1(a)huawei.com> --- V1->V2: CC mailist drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c index 9e3ab3b6c105..684c13aae4d0 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -2518,8 +2518,7 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev, list_add(&after->list, &tmp->bo_va->invalids); } - list_del(&tmp->list); - list_add(&tmp->list, &removed); + list_move(&tmp->list, &removed); tmp = amdgpu_vm_it_iter_next(tmp, saddr, eaddr); }

4 years, 3 months

[PATCH -next v2] drm/ttm: use list_move instead of list_del/list_add in ttm_execbuf_util.c

by Baokun Li

Using list_move() instead of list_del() + list_add() in ttm_execbuf_util.c. Reported-by: Hulk Robot <hulkci(a)huawei.com> Signed-off-by: Baokun Li <libaokun1(a)huawei.com> --- V1->V2: CC mailist drivers/gpu/drm/ttm/ttm_execbuf_util.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c b/drivers/gpu/drm/ttm/ttm_execbuf_util.c index 071c48d672c6..c50943888d04 100644 --- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c @@ -95,8 +95,7 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket, if (ret == -EALREADY && dups) { struct ttm_validate_buffer *safe = entry; entry = list_prev_entry(entry, head); - list_del(&safe->head); - list_add(&safe->head, dups); + list_move(&safe->head, dups); continue; } @@ -135,8 +134,7 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket, /* move this item to the front of the list, * forces correct iteration of the loop without keeping track */ - list_del(&entry->head); - list_add(&entry->head, list); + list_move(&entry->head, list); } return 0;

4 years, 3 months

Re: [Linaro-mm-sig] [PATCH] dma-buf: fix build due to missing export

by Christian König

That was an already known issue and I've just pushed a patch to fix it. Christian. Am 05.06.21 um 02:20 schrieb Lucas De Marchi: > Commit 0c6b522abc2a ("dma-buf: cleanup dma-resv shared fence debugging a bit v2") > turned dma_resv_reset_shared_max() into a function when > CONFIG_DEBUG_MUTEXES is set, but forgot to export it. That resulted in a > broken build: > > ERROR: modpost: "dma_resv_reset_shared_max" [drivers/gpu/drm/vgem/vgem.ko] undefined! > ERROR: modpost: "dma_resv_reset_shared_max" [drivers/gpu/drm/i915/i915.ko] undefined! > ERROR: modpost: "dma_resv_reset_shared_max" [drivers/gpu/drm/amd/amdgpu/amdgpu.ko] undefined! > ERROR: modpost: "dma_resv_reset_shared_max" [drivers/gpu/drm/ttm/ttm.ko] undefined! > ERROR: modpost: "dma_resv_reset_shared_max" [drivers/gpu/drm/drm.ko] undefined! > ERROR: modpost: "dma_resv_reset_shared_max" [drivers/gpu/drm/drm_vram_helper.ko] undefined! > make[1]: *** [scripts/Makefile.modpost:150: modules-only.symvers] Error 1 > > Fixes: 0c6b522abc2a ("dma-buf: cleanup dma-resv shared fence debugging a bit v2") > Cc: Christian König <christian.koenig(a)amd.com> > Cc: Daniel Vetter <daniel.vetter(a)ffwll.ch> > Cc: Sumit Semwal <sumit.semwal(a)linaro.org> > Cc: "Christian König" <christian.koenig(a)amd.com> > Cc: linux-media(a)vger.kernel.org > Cc: dri-devel(a)lists.freedesktop.org > Cc: linaro-mm-sig(a)lists.linaro.org > Signed-off-by: Lucas De Marchi <lucas.demarchi(a)intel.com> > --- > drivers/dma-buf/dma-resv.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c > index 3964df438505..6132ba631991 100644 > --- a/drivers/dma-buf/dma-resv.c > +++ b/drivers/dma-buf/dma-resv.c > @@ -226,6 +226,7 @@ void dma_resv_reset_shared_max(struct dma_resv *obj) > fence->shared_max = fence->shared_count; > } > } > +EXPORT_SYMBOL(dma_resv_reset_shared_max); > #endif > > /**

4 years, 3 months

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

Linaro-mm-sig