summaryrefslogtreecommitdiffstats
path: root/debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch
diff options
context:
space:
mode:
Diffstat (limited to 'debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch')
-rw-r--r--debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch173
1 files changed, 83 insertions, 90 deletions
diff --git a/debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch b/debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch
index ef03b75ac..a6f2aa326 100644
--- a/debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch
+++ b/debian/patches-rt/dma-buf-Use-seqlock_t-instread-disabling-preemption.patch
@@ -1,10 +1,10 @@
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Wed, 14 Aug 2019 16:38:43 +0200
Subject: [PATCH] dma-buf: Use seqlock_t instread disabling preemption
-Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patches-5.2.17-rt9.tar.xz
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.4/older/patches-5.4.3-rt1.tar.xz
"dma reservation" disables preemption while acquiring the write access
-for "seqcount" and then may acquire a spinlock_t.
+for "seqcount".
Replace the seqcount with a seqlock_t which provides seqcount like
semantic and lock for writer.
@@ -13,15 +13,15 @@ Link: https://lkml.kernel.org/r/f410b429-db86-f81c-7c67-f563fa808b62@free.fr
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
drivers/dma-buf/dma-buf.c | 8 ++--
- drivers/dma-buf/reservation.c | 40 ++++++++---------------
+ drivers/dma-buf/dma-resv.c | 45 ++++++++---------------
drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 6 +--
- drivers/gpu/drm/i915/i915_gem.c | 10 ++---
- include/linux/reservation.h | 4 +-
- 5 files changed, 28 insertions(+), 40 deletions(-)
+ drivers/gpu/drm/i915/gem/i915_gem_busy.c | 6 +--
+ include/linux/dma-resv.h | 4 +-
+ 5 files changed, 27 insertions(+), 42 deletions(-)
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
-@@ -168,7 +168,7 @@ static __poll_t dma_buf_poll(struct file
+@@ -214,7 +214,7 @@ static __poll_t dma_buf_poll(struct file
return 0;
retry:
@@ -30,7 +30,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
rcu_read_lock();
fobj = rcu_dereference(resv->fence);
-@@ -177,7 +177,7 @@ static __poll_t dma_buf_poll(struct file
+@@ -223,7 +223,7 @@ static __poll_t dma_buf_poll(struct file
else
shared_count = 0;
fence_excl = rcu_dereference(resv->fence_excl);
@@ -39,7 +39,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
rcu_read_unlock();
goto retry;
}
-@@ -1034,12 +1034,12 @@ static int dma_buf_debug_show(struct seq
+@@ -1189,12 +1189,12 @@ static int dma_buf_debug_show(struct seq
robj = buf_obj->resv;
while (true) {
@@ -54,28 +54,33 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
break;
rcu_read_unlock();
}
---- a/drivers/dma-buf/reservation.c
-+++ b/drivers/dma-buf/reservation.c
-@@ -110,15 +110,13 @@ int reservation_object_reserve_shared(st
- new->shared_count = j;
- new->shared_max = max;
+--- a/drivers/dma-buf/dma-resv.c
++++ b/drivers/dma-buf/dma-resv.c
+@@ -49,12 +49,6 @@
+ DEFINE_WD_CLASS(reservation_ww_class);
+ EXPORT_SYMBOL(reservation_ww_class);
-- preempt_disable();
-- write_seqcount_begin(&obj->seq);
-+ write_seqlock(&obj->seq);
- /*
- * RCU_INIT_POINTER can be used here,
- * seqcount provides the necessary barriers
- */
- RCU_INIT_POINTER(obj->fence, new);
-- write_seqcount_end(&obj->seq);
-- preempt_enable();
-+ write_sequnlock(&obj->seq);
+-struct lock_class_key reservation_seqcount_class;
+-EXPORT_SYMBOL(reservation_seqcount_class);
+-
+-const char reservation_seqcount_string[] = "reservation_seqcount";
+-EXPORT_SYMBOL(reservation_seqcount_string);
+-
+ /**
+ * dma_resv_list_alloc - allocate fence list
+ * @shared_max: number of fences we need space for
+@@ -103,8 +97,7 @@ void dma_resv_init(struct dma_resv *obj)
+ {
+ ww_mutex_init(&obj->lock, &reservation_ww_class);
- if (!old)
- return 0;
-@@ -158,8 +156,7 @@ void reservation_object_add_shared_fence
- fobj = reservation_object_get_list(obj);
+- __seqcount_init(&obj->seq, reservation_seqcount_string,
+- &reservation_seqcount_class);
++ seqlock_init(&obj->seq);
+ RCU_INIT_POINTER(obj->fence, NULL);
+ RCU_INIT_POINTER(obj->fence_excl, NULL);
+ }
+@@ -234,8 +227,7 @@ void dma_resv_add_shared_fence(struct dm
+ fobj = dma_resv_get_list(obj);
count = fobj->shared_count;
- preempt_disable();
@@ -83,18 +88,18 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+ write_seqlock(&obj->seq);
for (i = 0; i < count; ++i) {
- struct dma_fence *old_fence;
-@@ -181,8 +178,7 @@ void reservation_object_add_shared_fence
+
+@@ -255,8 +247,7 @@ void dma_resv_add_shared_fence(struct dm
/* pointer update must be visible before we extend the shared_count */
smp_store_mb(fobj->shared_count, count);
- write_seqcount_end(&obj->seq);
- preempt_enable();
+ write_sequnlock(&obj->seq);
+ dma_fence_put(old);
}
- EXPORT_SYMBOL(reservation_object_add_shared_fence);
-
-@@ -209,14 +205,11 @@ void reservation_object_add_excl_fence(s
+ EXPORT_SYMBOL(dma_resv_add_shared_fence);
+@@ -283,14 +274,12 @@ void dma_resv_add_excl_fence(struct dma_
if (fence)
dma_fence_get(fence);
@@ -102,6 +107,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
- write_seqcount_begin(&obj->seq);
- /* write_seqcount_begin provides the necessary memory barrier */
+ write_seqlock(&obj->seq);
++ /* write_seqlock provides the necessary memory barrier */
RCU_INIT_POINTER(obj->fence_excl, fence);
if (old)
old->shared_count = 0;
@@ -111,23 +117,24 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
/* inplace update, no shared fences */
while (i--)
-@@ -298,13 +291,10 @@ int reservation_object_copy_fences(struc
- src_list = reservation_object_get_list(dst);
- old = reservation_object_get_excl(dst);
+@@ -368,13 +357,11 @@ int dma_resv_copy_fences(struct dma_resv
+ src_list = dma_resv_get_list(dst);
+ old = dma_resv_get_excl(dst);
- preempt_disable();
- write_seqcount_begin(&dst->seq);
- /* write_seqcount_begin provides the necessary memory barrier */
+ write_seqlock(&dst->seq);
++ /* write_seqlock provides the necessary memory barrier */
RCU_INIT_POINTER(dst->fence_excl, new);
RCU_INIT_POINTER(dst->fence, dst_list);
- write_seqcount_end(&dst->seq);
- preempt_enable();
+ write_sequnlock(&dst->seq);
- if (src_list)
- kfree_rcu(src_list, rcu);
-@@ -345,7 +335,7 @@ int reservation_object_get_fences_rcu(st
+ dma_resv_list_free(src_list);
+ dma_fence_put(old);
+@@ -414,7 +401,7 @@ int dma_resv_get_fences_rcu(struct dma_r
shared_count = i = 0;
rcu_read_lock();
@@ -136,7 +143,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
fence_excl = rcu_dereference(obj->fence_excl);
if (fence_excl && !dma_fence_get_rcu(fence_excl))
-@@ -394,7 +384,7 @@ int reservation_object_get_fences_rcu(st
+@@ -456,7 +443,7 @@ int dma_resv_get_fences_rcu(struct dma_r
}
}
@@ -145,7 +152,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
while (i--)
dma_fence_put(shared[i]);
dma_fence_put(fence_excl);
-@@ -443,7 +433,7 @@ long reservation_object_wait_timeout_rcu
+@@ -507,7 +494,7 @@ long dma_resv_wait_timeout_rcu(struct dm
retry:
shared_count = 0;
@@ -154,7 +161,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
rcu_read_lock();
i = -1;
-@@ -490,7 +480,7 @@ long reservation_object_wait_timeout_rcu
+@@ -553,7 +540,7 @@ long dma_resv_wait_timeout_rcu(struct dm
rcu_read_unlock();
if (fence) {
@@ -163,7 +170,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
dma_fence_put(fence);
goto retry;
}
-@@ -546,7 +536,7 @@ bool reservation_object_test_signaled_rc
+@@ -607,7 +594,7 @@ bool dma_resv_test_signaled_rcu(struct d
retry:
ret = true;
shared_count = 0;
@@ -172,7 +179,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
if (test_all) {
unsigned i;
-@@ -567,7 +557,7 @@ bool reservation_object_test_signaled_rc
+@@ -627,7 +614,7 @@ bool dma_resv_test_signaled_rcu(struct d
break;
}
@@ -181,7 +188,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
goto retry;
}
-@@ -580,7 +570,7 @@ bool reservation_object_test_signaled_rc
+@@ -639,7 +626,7 @@ bool dma_resv_test_signaled_rcu(struct d
if (ret < 0)
goto retry;
@@ -192,7 +199,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
}
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
-@@ -250,11 +250,9 @@ static int amdgpu_amdkfd_remove_eviction
+@@ -252,11 +252,9 @@ static int amdgpu_amdkfd_remove_eviction
new->shared_count = k;
/* Install the new fence list, seqcount provides the barriers */
@@ -206,64 +213,50 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
/* Drop the references to the removed fences or move them to ef_list */
for (i = j, k = 0; i < old->shared_count; ++i) {
---- a/drivers/gpu/drm/i915/i915_gem.c
-+++ b/drivers/gpu/drm/i915/i915_gem.c
-@@ -449,7 +449,7 @@ i915_gem_object_wait_reservation(struct
- unsigned int flags,
- long timeout)
- {
-- unsigned int seq = __read_seqcount_begin(&resv->seq);
-+ unsigned int seq = read_seqbegin(&resv->seq);
- struct dma_fence *excl;
- bool prune_fences = false;
+--- a/drivers/gpu/drm/i915/gem/i915_gem_busy.c
++++ b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
+@@ -75,7 +75,6 @@ busy_check_writer(const struct dma_fence
-@@ -500,9 +500,9 @@ i915_gem_object_wait_reservation(struct
- * signaled and that the reservation object has not been changed (i.e.
- * no new fences have been added).
- */
-- if (prune_fences && !__read_seqcount_retry(&resv->seq, seq)) {
-+ if (prune_fences && !read_seqretry(&resv->seq, seq)) {
- if (reservation_object_trylock(resv)) {
-- if (!__read_seqcount_retry(&resv->seq, seq))
-+ if (!read_seqretry(&resv->seq, seq))
- reservation_object_add_excl_fence(resv, NULL);
- reservation_object_unlock(resv);
- }
-@@ -3943,7 +3943,7 @@ i915_gem_busy_ioctl(struct drm_device *d
+ return __busy_set_if_active(fence, __busy_write_id);
+ }
+-
+ int
+ i915_gem_busy_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file)
+@@ -110,7 +109,8 @@ i915_gem_busy_ioctl(struct drm_device *d
*
*/
retry:
-- seq = raw_read_seqcount(&obj->resv->seq);
-+ seq = read_seqbegin(&obj->resv->seq);
+- seq = raw_read_seqcount(&obj->base.resv->seq);
++ /* XXX raw_read_seqcount() does not wait for the WRTIE to finish */
++ seq = read_seqbegin(&obj->base.resv->seq);
/* Translate the exclusive fence to the READ *and* WRITE engine */
- args->busy = busy_check_writer(rcu_dereference(obj->resv->fence_excl));
-@@ -3961,7 +3961,7 @@ i915_gem_busy_ioctl(struct drm_device *d
+ args->busy =
+@@ -129,7 +129,7 @@ i915_gem_busy_ioctl(struct drm_device *d
}
}
-- if (args->busy && read_seqcount_retry(&obj->resv->seq, seq))
-+ if (args->busy && read_seqretry(&obj->resv->seq, seq))
+- if (args->busy && read_seqcount_retry(&obj->base.resv->seq, seq))
++ if (args->busy && read_seqretry(&obj->base.resv->seq, seq))
goto retry;
err = 0;
---- a/include/linux/reservation.h
-+++ b/include/linux/reservation.h
-@@ -71,7 +71,7 @@ struct reservation_object_list {
+--- a/include/linux/dma-resv.h
++++ b/include/linux/dma-resv.h
+@@ -65,13 +65,13 @@ struct dma_resv_list {
+ /**
+ * struct dma_resv - a reservation object manages fences for a buffer
+ * @lock: update side lock
+- * @seq: sequence count for managing RCU read-side synchronization
++ * @seq: sequence lock for managing RCU read-side synchronization
+ * @fence_excl: the exclusive fence, if there is one currently
+ * @fence: list of current shared fences
*/
- struct reservation_object {
+ struct dma_resv {
struct ww_mutex lock;
- seqcount_t seq;
+ seqlock_t seq;
struct dma_fence __rcu *fence_excl;
- struct reservation_object_list __rcu *fence;
-@@ -90,7 +90,7 @@ reservation_object_init(struct reservati
- {
- ww_mutex_init(&obj->lock, &reservation_ww_class);
-
-- __seqcount_init(&obj->seq, reservation_seqcount_string, &reservation_seqcount_class);
-+ seqlock_init(&obj->seq);
- RCU_INIT_POINTER(obj->fence, NULL);
- RCU_INIT_POINTER(obj->fence_excl, NULL);
- }
+ struct dma_resv_list __rcu *fence;
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-15 05:20:01 +0000