From: Thomas Zimmermann <tzimmermann@suse.de>
To: Rob Clark <robin.clark@oss.qualcomm.com>,
dri-devel@lists.freedesktop.org
Cc: Boris Brezillon <boris.brezillon@collabora.com>,
Liviu Dudau <liviu.dudau@arm.com>,
Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Maxime Ripard <mripard@kernel.org>,
David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>,
Dmitry Baryshkov <lumag@kernel.org>,
Abhinav Kumar <abhinav.kumar@linux.dev>,
Jessica Zhang <jesszhan0024@gmail.com>,
Sean Paul <sean@poorly.run>,
Marijn Suijten <marijn.suijten@somainline.org>,
Steven Price <steven.price@arm.com>,
open list <linux-kernel@vger.kernel.org>,
"open list:DRM DRIVER for Qualcomm display hardware"
<linux-arm-msm@vger.kernel.org>,
"open list:DRM DRIVER for Qualcomm display hardware"
<freedreno@lists.freedesktop.org>
Subject: Re: [PATCH v2] drm/gem: Drop ticket arg to lru_scan()
Date: Wed, 2 Sep 2026 08:57:07 +0200 [thread overview]
Message-ID: <69a37b53-82e1-40bb-8266-206c3bff6af2@suse.de> (raw)
In-Reply-To: <20260901164544.642985-1-robin.clark@oss.qualcomm.com>
Am 01.09.26 um 18:45 schrieb Rob Clark:
> Commit 3392291fc509 ("drm/msm: Fix shrinker deadlock") dropped the only
> use of the ticket arg, but at the time left drm_gem_lru_scan() unchanged
> to avoid conflicts with in-flight panthor shrinker support. This commit
> is the followup to remove the unused arg.
>
> Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
> Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
>
> v2: Drop left over kerneldoc param description, fix panthor spelling
>
> drivers/gpu/drm/drm_gem.c | 14 +++-----------
> drivers/gpu/drm/msm/msm_gem_shrinker.c | 22 ++++++++++------------
> drivers/gpu/drm/panthor/panthor_gem.c | 14 ++++++--------
> drivers/gpu/drm/panthor/panthor_mmu.c | 5 ++---
> drivers/gpu/drm/panthor/panthor_mmu.h | 3 +--
> include/drm/drm_gem.h | 3 +--
> 6 files changed, 23 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
> index e3ed684ddcf2..3113b4a53b99 100644
> --- a/drivers/gpu/drm/drm_gem.c
> +++ b/drivers/gpu/drm/drm_gem.c
> @@ -1649,15 +1649,13 @@ EXPORT_SYMBOL(drm_gem_lru_move_tail);
> * @nr_to_scan: The number of pages to try to reclaim
> * @remaining: The number of pages left to reclaim, should be initialized by caller
> * @shrink: Callback to try to shrink/reclaim the object.
> - * @ticket: Optional ww_acquire_ctx context to use for locking
> */
> unsigned long
> drm_gem_lru_scan(struct drm_device *dev,
> struct drm_gem_lru *lru,
> unsigned int nr_to_scan,
> unsigned long *remaining,
> - bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket),
> - struct ww_acquire_ctx *ticket)
> + bool (*shrink)(struct drm_gem_object *obj))
> {
> struct drm_gem_lru still_in_lru;
> struct drm_gem_object *obj;
> @@ -1690,20 +1688,17 @@ drm_gem_lru_scan(struct drm_device *dev,
> */
> mutex_unlock(&dev->gem_lru_mutex);
>
> - if (ticket)
> - ww_acquire_init(ticket, &reservation_ww_class);
> -
> /*
> * Note that this still needs to be trylock, since we can
> * hit shrinker in response to trying to get backing pages
> * for this obj (ie. while it's lock is already held)
> */
> - if (!ww_mutex_trylock(&obj->resv->lock, ticket)) {
> + if (!ww_mutex_trylock(&obj->resv->lock, NULL)) {
> *remaining += obj->size >> PAGE_SHIFT;
> goto tail;
> }
>
> - if (shrink(obj, ticket)) {
> + if (shrink(obj)) {
> freed += obj->size >> PAGE_SHIFT;
>
> /*
> @@ -1727,9 +1722,6 @@ drm_gem_lru_scan(struct drm_device *dev,
>
> dma_resv_unlock(obj->resv);
>
> - if (ticket)
> - ww_acquire_fini(ticket);
> -
> tail:
> drm_gem_object_put(obj);
> mutex_lock(&dev->gem_lru_mutex);
> diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c
> index 9d2788f79ace..3514d5c84989 100644
> --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c
> +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c
> @@ -102,7 +102,7 @@ with_vm_locks(void (*fn)(struct drm_gem_object *obj),
> }
>
> static bool
> -purge(struct drm_gem_object *obj, struct ww_acquire_ctx *unused)
> +purge(struct drm_gem_object *obj)
> {
> if (!is_purgeable(to_msm_bo(obj)))
> return false;
> @@ -114,7 +114,7 @@ purge(struct drm_gem_object *obj, struct ww_acquire_ctx *unused)
> }
>
> static bool
> -evict(struct drm_gem_object *obj, struct ww_acquire_ctx *unused)
> +evict(struct drm_gem_object *obj)
> {
> if (is_unevictable(to_msm_bo(obj)))
> return false;
> @@ -133,21 +133,21 @@ wait_for_idle(struct drm_gem_object *obj)
> }
>
> static bool
> -active_purge(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket)
> +active_purge(struct drm_gem_object *obj)
> {
> if (!wait_for_idle(obj))
> return false;
>
> - return purge(obj, ticket);
> + return purge(obj);
> }
>
> static bool
> -active_evict(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket)
> +active_evict(struct drm_gem_object *obj)
> {
> if (!wait_for_idle(obj))
> return false;
>
> - return evict(obj, ticket);
> + return evict(obj);
> }
>
> static unsigned long
> @@ -156,7 +156,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
> struct msm_drm_private *priv = shrinker->private_data;
> struct {
> struct drm_gem_lru *lru;
> - bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket);
> + bool (*shrink)(struct drm_gem_object *obj);
> bool cond;
> unsigned long freed;
> unsigned long remaining;
> @@ -180,8 +180,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
> stages[i].freed =
> drm_gem_lru_scan(priv->dev, stages[i].lru, nr,
> &stages[i].remaining,
> - stages[i].shrink,
> - NULL);
> + stages[i].shrink);
> nr -= stages[i].freed;
> freed += stages[i].freed;
> remaining += stages[i].remaining;
> @@ -222,7 +221,7 @@ msm_gem_shrinker_shrink(struct drm_device *dev, unsigned long nr_to_scan)
> static const int vmap_shrink_limit = 15;
>
> static bool
> -vmap_shrink(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket)
> +vmap_shrink(struct drm_gem_object *obj)
> {
> if (!is_vunmapable(to_msm_bo(obj)))
> return false;
> @@ -250,8 +249,7 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr)
> unmapped += drm_gem_lru_scan(priv->dev, lrus[idx],
> vmap_shrink_limit - unmapped,
> &remaining,
> - vmap_shrink,
> - NULL);
> + vmap_shrink);
> }
>
> *(unsigned long *)ptr += unmapped;
> diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
> index 54535bae2b0c..17408f832af3 100644
> --- a/drivers/gpu/drm/panthor/panthor_gem.c
> +++ b/drivers/gpu/drm/panthor/panthor_gem.c
> @@ -1392,8 +1392,7 @@ panthor_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
> return count ? count : SHRINK_EMPTY;
> }
>
> -static bool panthor_gem_try_evict_no_resv_wait(struct drm_gem_object *obj,
> - struct ww_acquire_ctx *ticket)
> +static bool panthor_gem_try_evict_no_resv_wait(struct drm_gem_object *obj)
> {
> /*
> * Track last locked entry for unwinding locks in error and
> @@ -1479,8 +1478,7 @@ static bool panthor_gem_try_evict_no_resv_wait(struct drm_gem_object *obj,
> return ret == 0;
> }
>
> -static bool panthor_gem_try_evict(struct drm_gem_object *obj,
> - struct ww_acquire_ctx *ticket)
> +static bool panthor_gem_try_evict(struct drm_gem_object *obj)
> {
> struct panthor_gem_object *bo = to_panthor_bo(obj);
>
> @@ -1488,7 +1486,7 @@ static bool panthor_gem_try_evict(struct drm_gem_object *obj,
> if (dma_resv_wait_timeout(obj->resv, DMA_RESV_USAGE_BOOKKEEP, false, 10) <= 0)
> return false;
>
> - return panthor_gem_try_evict_no_resv_wait(&bo->base, ticket);
> + return panthor_gem_try_evict_no_resv_wait(&bo->base);
> }
>
> static unsigned long
> @@ -1503,13 +1501,13 @@ panthor_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
>
> freed += drm_gem_lru_scan(&ptdev->base, &ptdev->reclaim.unused,
> sc->nr_to_scan - freed, &remaining,
> - panthor_gem_try_evict_no_resv_wait, NULL);
> + panthor_gem_try_evict_no_resv_wait);
> if (freed >= sc->nr_to_scan)
> goto out;
>
> freed += drm_gem_lru_scan(&ptdev->base, &ptdev->reclaim.mmapped,
> sc->nr_to_scan - freed, &remaining,
> - panthor_gem_try_evict_no_resv_wait, NULL);
> + panthor_gem_try_evict_no_resv_wait);
> if (freed >= sc->nr_to_scan)
> goto out;
>
> @@ -1523,7 +1521,7 @@ panthor_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
>
> freed += drm_gem_lru_scan(&ptdev->base, &ptdev->reclaim.gpu_mapped_shared,
> sc->nr_to_scan - freed, &remaining,
> - panthor_gem_try_evict, NULL);
> + panthor_gem_try_evict);
>
> out:
> #ifdef CONFIG_DEBUG_FS
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
> index e10dbd18d8cf..ab070bc74857 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.c
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.c
> @@ -3133,8 +3133,7 @@ int panthor_vm_prepare_mapped_bos_resvs(struct drm_exec *exec, struct panthor_vm
> unsigned long
> panthor_mmu_reclaim_priv_bos(struct panthor_device *ptdev,
> unsigned int nr_to_scan, unsigned long *remaining,
> - bool (*shrink)(struct drm_gem_object *,
> - struct ww_acquire_ctx *))
> + bool (*shrink)(struct drm_gem_object *))
> {
> unsigned long freed = 0;
> LIST_HEAD(remaining_vms);
> @@ -3160,7 +3159,7 @@ panthor_mmu_reclaim_priv_bos(struct panthor_device *ptdev,
>
> freed += drm_gem_lru_scan(&ptdev->base, &vm->reclaim.lru,
> nr_to_scan - freed,
> - remaining, shrink, NULL);
> + remaining, shrink);
>
> mutex_lock(&ptdev->base.gem_lru_mutex);
>
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.h b/drivers/gpu/drm/panthor/panthor_mmu.h
> index 3522fbbce369..abc36e7204be 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.h
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.h
> @@ -52,8 +52,7 @@ int panthor_vm_evict_bo_mappings_locked(struct panthor_gem_object *bo);
> unsigned long
> panthor_mmu_reclaim_priv_bos(struct panthor_device *ptdev,
> unsigned int nr_to_scan, unsigned long *remaining,
> - bool (*shrink)(struct drm_gem_object *,
> - struct ww_acquire_ctx *));
> + bool (*shrink)(struct drm_gem_object *));
> int panthor_vm_prepare_mapped_bos_resvs(struct drm_exec *exec,
> struct panthor_vm *vm,
> u32 slot_count);
> diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
> index 8a704f6a65c1..ffa607c91aa2 100644
> --- a/include/drm/drm_gem.h
> +++ b/include/drm/drm_gem.h
> @@ -616,8 +616,7 @@ drm_gem_lru_scan(struct drm_device *dev,
> struct drm_gem_lru *lru,
> unsigned int nr_to_scan,
> unsigned long *remaining,
> - bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket),
> - struct ww_acquire_ctx *ticket);
> + bool (*shrink)(struct drm_gem_object *obj));
>
> int drm_gem_evict_locked(struct drm_gem_object *obj);
>
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, (HRB 36809, AG Nürnberg)
next prev parent reply other threads:[~2026-09-02 6:57 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-01 16:45 Rob Clark
2026-09-02 6:57 ` Thomas Zimmermann [this message]
2026-09-03 14:09 ` Rob Clark
2026-09-03 15:11 ` Thomas Zimmermann
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=69a37b53-82e1-40bb-8266-206c3bff6af2@suse.de \
--to=tzimmermann@suse.de \
--cc=abhinav.kumar@linux.dev \
--cc=airlied@gmail.com \
--cc=boris.brezillon@collabora.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=freedreno@lists.freedesktop.org \
--cc=jesszhan0024@gmail.com \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=liviu.dudau@arm.com \
--cc=lumag@kernel.org \
--cc=maarten.lankhorst@linux.intel.com \
--cc=marijn.suijten@somainline.org \
--cc=mripard@kernel.org \
--cc=robin.clark@oss.qualcomm.com \
--cc=sean@poorly.run \
--cc=simona@ffwll.ch \
--cc=steven.price@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®