[PATCH v5 06/21] gpu: host1x: Cleanup and refcounting for syncpoints

Mikko Perttunen
2021-01-11T13:02:14Z

Add reference counting for allocated syncpoints to allow keeping
them allocated while jobs are referencing them. Additionally,
clean up various places using syncpoint IDs to use host1x_syncpt
pointers instead.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
v5:
- Remove host1x_syncpt_put in submit code, as job_put already
puts the syncpoint.
- Changes due to rebase in VI driver.
v4:
- Update from _free to _put in VI driver as well
---
drivers/gpu/drm/tegra/dc.c | 4 +-
drivers/gpu/drm/tegra/drm.c | 14 ++---
drivers/gpu/drm/tegra/gr2d.c | 4 +-
drivers/gpu/drm/tegra/gr3d.c | 4 +-
drivers/gpu/drm/tegra/vic.c | 4 +-
drivers/gpu/host1x/cdma.c | 11 ++--
drivers/gpu/host1x/dev.h | 7 ++-
drivers/gpu/host1x/hw/cdma_hw.c | 2 +-
drivers/gpu/host1x/hw/channel_hw.c | 10 ++--
drivers/gpu/host1x/hw/debug_hw.c | 2 +-
drivers/gpu/host1x/job.c | 5 +-
drivers/gpu/host1x/syncpt.c | 75 +++++++++++++++++++-------
drivers/gpu/host1x/syncpt.h | 3 ++
drivers/staging/media/tegra-video/vi.c | 4 +-
include/linux/host1x.h | 8 +--
15 files changed, 98 insertions(+), 59 deletions(-)

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 85dd7131553a..033032dfc4b9 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -2129,7 +2129,7 @@ static int tegra_dc_init(struct host1x_client *client)
drm_plane_cleanup(primary);

host1x_client_iommu_detach(client);
- host1x_syncpt_free(dc->syncpt);
+ host1x_syncpt_put(dc->syncpt);

return err;
}
@@ -2154,7 +2154,7 @@ static int tegra_dc_exit(struct host1x_client *client)
}

host1x_client_iommu_detach(client);
- host1x_syncpt_free(dc->syncpt);
+ host1x_syncpt_put(dc->syncpt);

return 0;
}
diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index e45c8414e2a3..5a6037eff37f 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -171,7 +171,7 @@ int tegra_drm_submit(struct tegra_drm_context *context,
struct drm_tegra_syncpt syncpt;
struct host1x *host1x = dev_get_drvdata(drm->dev->parent);
struct drm_gem_object **refs;
- struct host1x_syncpt *sp;
+ struct host1x_syncpt *sp = NULL;
struct host1x_job *job;
unsigned int num_refs;
int err;
@@ -298,8 +298,8 @@ int tegra_drm_submit(struct tegra_drm_context *context,
goto fail;
}

- /* check whether syncpoint ID is valid */
- sp = host1x_syncpt_get(host1x, syncpt.id);
+ /* Syncpoint ref will be dropped on job release. */
+ sp = host1x_syncpt_get_by_id(host1x, syncpt.id);
if (!sp) {
err = -ENOENT;
goto fail;
@@ -308,7 +308,7 @@ int tegra_drm_submit(struct tegra_drm_context *context,
job->is_addr_reg = context->client->ops->is_addr_reg;
job->is_valid_class = context->client->ops->is_valid_class;
job->syncpt_incrs = syncpt.incrs;
- job->syncpt_id = syncpt.id;
+ job->syncpt = sp;
job->timeout = 10000;

if (args->timeout && args->timeout < 10000)
@@ -380,7 +380,7 @@ static int tegra_syncpt_read(struct drm_device *drm, void *data,
struct drm_tegra_syncpt_read *args = data;
struct host1x_syncpt *sp;

- sp = host1x_syncpt_get(host, args->id);
+ sp = host1x_syncpt_get_by_id_noref(host, args->id);
if (!sp)
return -EINVAL;

@@ -395,7 +395,7 @@ static int tegra_syncpt_incr(struct drm_device *drm, void *data,
struct drm_tegra_syncpt_incr *args = data;
struct host1x_syncpt *sp;

- sp = host1x_syncpt_get(host1x, args->id);
+ sp = host1x_syncpt_get_by_id_noref(host1x, args->id);
if (!sp)
return -EINVAL;

@@ -409,7 +409,7 @@ static int tegra_syncpt_wait(struct drm_device *drm, void *data,
struct drm_tegra_syncpt_wait *args = data;
struct host1x_syncpt *sp;

- sp = host1x_syncpt_get(host1x, args->id);
+ sp = host1x_syncpt_get_by_id_noref(host1x, args->id);
if (!sp)
return -EINVAL;

diff --git a/drivers/gpu/drm/tegra/gr2d.c b/drivers/gpu/drm/tegra/gr2d.c
index 1a0d3ba6e525..d857a99b21a7 100644
--- a/drivers/gpu/drm/tegra/gr2d.c
+++ b/drivers/gpu/drm/tegra/gr2d.c
@@ -67,7 +67,7 @@ static int gr2d_init(struct host1x_client *client)
detach:
host1x_client_iommu_detach(client);
free:
- host1x_syncpt_free(client->syncpts[0]);
+ host1x_syncpt_put(client->syncpts[0]);
put:
host1x_channel_put(gr2d->channel);
return err;
@@ -86,7 +86,7 @@ static int gr2d_exit(struct host1x_client *client)
return err;

host1x_client_iommu_detach(client);
- host1x_syncpt_free(client->syncpts[0]);
+ host1x_syncpt_put(client->syncpts[0]);
host1x_channel_put(gr2d->channel);

return 0;
diff --git a/drivers/gpu/drm/tegra/gr3d.c b/drivers/gpu/drm/tegra/gr3d.c
index b0b8154e8104..24442ade0da3 100644
--- a/drivers/gpu/drm/tegra/gr3d.c
+++ b/drivers/gpu/drm/tegra/gr3d.c
@@ -76,7 +76,7 @@ static int gr3d_init(struct host1x_client *client)
detach:
host1x_client_iommu_detach(client);
free:
- host1x_syncpt_free(client->syncpts[0]);
+ host1x_syncpt_put(client->syncpts[0]);
put:
host1x_channel_put(gr3d->channel);
return err;
@@ -94,7 +94,7 @@ static int gr3d_exit(struct host1x_client *client)
return err;

host1x_client_iommu_detach(client);
- host1x_syncpt_free(client->syncpts[0]);
+ host1x_syncpt_put(client->syncpts[0]);
host1x_channel_put(gr3d->channel);

return 0;
diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c
index ade56b860cf9..cb476da59adc 100644
--- a/drivers/gpu/drm/tegra/vic.c
+++ b/drivers/gpu/drm/tegra/vic.c
@@ -197,7 +197,7 @@ static int vic_init(struct host1x_client *client)
return 0;

free_syncpt:
- host1x_syncpt_free(client->syncpts[0]);
+ host1x_syncpt_put(client->syncpts[0]);
free_channel:
host1x_channel_put(vic->channel);
detach:
@@ -221,7 +221,7 @@ static int vic_exit(struct host1x_client *client)
if (err < 0)
return err;

- host1x_syncpt_free(client->syncpts[0]);
+ host1x_syncpt_put(client->syncpts[0]);
host1x_channel_put(vic->channel);
host1x_client_iommu_detach(client);

diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c
index e8d3fda91d8a..6e6ca774f68d 100644
--- a/drivers/gpu/host1x/cdma.c
+++ b/drivers/gpu/host1x/cdma.c
@@ -273,15 +273,13 @@ static int host1x_cdma_wait_pushbuffer_space(struct host1x *host1x,
static void cdma_start_timer_locked(struct host1x_cdma *cdma,
struct host1x_job *job)
{
- struct host1x *host = cdma_to_host1x(cdma);
-
if (cdma->timeout.client) {
/* timer already started */
return;
}

cdma->timeout.client = job->client;
- cdma->timeout.syncpt = host1x_syncpt_get(host, job->syncpt_id);
+ cdma->timeout.syncpt = job->syncpt;
cdma->timeout.syncpt_val = job->syncpt_end;
cdma->timeout.start_ktime = ktime_get();

@@ -312,7 +310,6 @@ static void stop_cdma_timer_locked(struct host1x_cdma *cdma)
static void update_cdma_locked(struct host1x_cdma *cdma)
{
bool signal = false;
- struct host1x *host1x = cdma_to_host1x(cdma);
struct host1x_job *job, *n;

/* If CDMA is stopped, queue is cleared and we can return */
@@ -324,8 +321,7 @@ static void update_cdma_locked(struct host1x_cdma *cdma)
* to consume as many sync queue entries as possible without blocking
*/
list_for_each_entry_safe(job, n, &cdma->sync_queue, list) {
- struct host1x_syncpt *sp =
- host1x_syncpt_get(host1x, job->syncpt_id);
+ struct host1x_syncpt *sp = job->syncpt;

/* Check whether this syncpt has completed, and bail if not */
if (!host1x_syncpt_is_expired(sp, job->syncpt_end)) {
@@ -499,8 +495,7 @@ int host1x_cdma_begin(struct host1x_cdma *cdma, struct host1x_job *job)
if (!cdma->timeout.initialized) {
int err;

- err = host1x_hw_cdma_timeout_init(host1x, cdma,
- job->syncpt_id);
+ err = host1x_hw_cdma_timeout_init(host1x, cdma);
if (err) {
mutex_unlock(&cdma->lock);
return err;
diff --git a/drivers/gpu/host1x/dev.h b/drivers/gpu/host1x/dev.h
index f781a9b0f39d..63010ae37a97 100644
--- a/drivers/gpu/host1x/dev.h
+++ b/drivers/gpu/host1x/dev.h
@@ -37,7 +37,7 @@ struct host1x_cdma_ops {
void (*start)(struct host1x_cdma *cdma);
void (*stop)(struct host1x_cdma *cdma);
void (*flush)(struct host1x_cdma *cdma);
- int (*timeout_init)(struct host1x_cdma *cdma, unsigned int syncpt);
+ int (*timeout_init)(struct host1x_cdma *cdma);
void (*timeout_destroy)(struct host1x_cdma *cdma);
void (*freeze)(struct host1x_cdma *cdma);
void (*resume)(struct host1x_cdma *cdma, u32 getptr);
@@ -261,10 +261,9 @@ static inline void host1x_hw_cdma_flush(struct host1x *host,
}

static inline int host1x_hw_cdma_timeout_init(struct host1x *host,
- struct host1x_cdma *cdma,
- unsigned int syncpt)
+ struct host1x_cdma *cdma)
{
- return host->cdma_op->timeout_init(cdma, syncpt);
+ return host->cdma_op->timeout_init(cdma);
}

static inline void host1x_hw_cdma_timeout_destroy(struct host1x *host,
diff --git a/drivers/gpu/host1x/hw/cdma_hw.c b/drivers/gpu/host1x/hw/cdma_hw.c
index 2f3bf94cf365..e49cd5b8f735 100644
--- a/drivers/gpu/host1x/hw/cdma_hw.c
+++ b/drivers/gpu/host1x/hw/cdma_hw.c
@@ -295,7 +295,7 @@ static void cdma_timeout_handler(struct work_struct *work)
/*
* Init timeout resources
*/
-static int cdma_timeout_init(struct host1x_cdma *cdma, unsigned int syncpt)
+static int cdma_timeout_init(struct host1x_cdma *cdma)
{
INIT_DELAYED_WORK(&cdma->timeout.wq, cdma_timeout_handler);
cdma->timeout.initialized = true;
diff --git a/drivers/gpu/host1x/hw/channel_hw.c b/drivers/gpu/host1x/hw/channel_hw.c
index 5eaa29d171c9..d4c28faf27d1 100644
--- a/drivers/gpu/host1x/hw/channel_hw.c
+++ b/drivers/gpu/host1x/hw/channel_hw.c
@@ -86,8 +86,7 @@ static void submit_gathers(struct host1x_job *job)

static inline void synchronize_syncpt_base(struct host1x_job *job)
{
- struct host1x *host = dev_get_drvdata(job->channel->dev->parent);
- struct host1x_syncpt *sp = host->syncpt + job->syncpt_id;
+ struct host1x_syncpt *sp = job->syncpt;
unsigned int id;
u32 value;

@@ -118,7 +117,7 @@ static void host1x_channel_set_streamid(struct host1x_channel *channel)
static int channel_submit(struct host1x_job *job)
{
struct host1x_channel *ch = job->channel;
- struct host1x_syncpt *sp;
+ struct host1x_syncpt *sp = job->syncpt;
u32 user_syncpt_incrs = job->syncpt_incrs;
u32 prev_max = 0;
u32 syncval;
@@ -126,10 +125,9 @@ static int channel_submit(struct host1x_job *job)
struct host1x_waitlist *completed_waiter = NULL;
struct host1x *host = dev_get_drvdata(ch->dev->parent);

- sp = host->syncpt + job->syncpt_id;
trace_host1x_channel_submit(dev_name(ch->dev),
job->num_gathers, job->num_relocs,
- job->syncpt_id, job->syncpt_incrs);
+ job->syncpt->id, job->syncpt_incrs);

/* before error checks, return current max */
prev_max = job->syncpt_end = host1x_syncpt_read_max(sp);
@@ -163,7 +161,7 @@ static int channel_submit(struct host1x_job *job)
host1x_cdma_push(&ch->cdma,
host1x_opcode_setclass(HOST1X_CLASS_HOST1X,
host1x_uclass_wait_syncpt_r(), 1),
- host1x_class_host_wait_syncpt(job->syncpt_id,
+ host1x_class_host_wait_syncpt(job->syncpt->id,
host1x_syncpt_read_max(sp)));
}

diff --git a/drivers/gpu/host1x/hw/debug_hw.c b/drivers/gpu/host1x/hw/debug_hw.c
index f31bcfa1b837..ceb48229d14b 100644
--- a/drivers/gpu/host1x/hw/debug_hw.c
+++ b/drivers/gpu/host1x/hw/debug_hw.c
@@ -204,7 +204,7 @@ static void show_channel_gathers(struct output *o, struct host1x_cdma *cdma)
unsigned int i;

host1x_debug_output(o, "\n%p: JOB, syncpt_id=%d, syncpt_val=%d, first_get=%08x, timeout=%d num_slots=%d, num_handles=%d\n",
- job, job->syncpt_id, job->syncpt_end,
+ job, job->syncpt->id, job->syncpt_end,
job->first_get, job->timeout,
job->num_slots, job->num_unpins);

diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c
index 82d0a60ba3f7..adbdc225de8d 100644
--- a/drivers/gpu/host1x/job.c
+++ b/drivers/gpu/host1x/job.c
@@ -79,6 +79,9 @@ static void job_free(struct kref *ref)
{
struct host1x_job *job = container_of(ref, struct host1x_job, ref);

+ if (job->syncpt)
+ host1x_syncpt_put(job->syncpt);
+
kfree(job);
}

@@ -674,7 +677,7 @@ EXPORT_SYMBOL(host1x_job_unpin);
*/
void host1x_job_dump(struct device *dev, struct host1x_job *job)
{
- dev_dbg(dev, " SYNCPT_ID %d\n", job->syncpt_id);
+ dev_dbg(dev, " SYNCPT_ID %d\n", job->syncpt->id);
dev_dbg(dev, " SYNCPT_VAL %d\n", job->syncpt_end);
dev_dbg(dev, " FIRST_GET 0x%x\n", job->first_get);
dev_dbg(dev, " TIMEOUT %d\n", job->timeout);
diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c
index 9ccdf7709946..8a189a7c8d68 100644
--- a/drivers/gpu/host1x/syncpt.c
+++ b/drivers/gpu/host1x/syncpt.c
@@ -75,6 +75,8 @@ struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
else
sp->client_managed = false;

+ kref_init(&sp->ref);
+
mutex_unlock(&host->syncpt_mutex);
return sp;

@@ -368,7 +370,7 @@ int host1x_syncpt_init(struct host1x *host)
* host1x client drivers can use this function to allocate a syncpoint for
* subsequent use. A syncpoint returned by this function will be reserved for
* use by the client exclusively. When no longer using a syncpoint, a host1x
- * client driver needs to release it using host1x_syncpt_free().
+ * client driver needs to release it using host1x_syncpt_put().
*/
struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
unsigned long flags)
@@ -379,20 +381,9 @@ struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
}
EXPORT_SYMBOL(host1x_syncpt_request);

-/**
- * host1x_syncpt_free() - free a requested syncpoint
- * @sp: host1x syncpoint
- *
- * Release a syncpoint previously allocated using host1x_syncpt_request(). A
- * host1x client driver should call this when the syncpoint is no longer in
- * use. Note that client drivers must ensure that the syncpoint doesn't remain
- * under the control of hardware after calling this function, otherwise two
- * clients may end up trying to access the same syncpoint concurrently.
- */
-void host1x_syncpt_free(struct host1x_syncpt *sp)
+static void syncpt_release(struct kref *ref)
{
- if (!sp)
- return;
+ struct host1x_syncpt *sp = container_of(ref, struct host1x_syncpt, ref);

mutex_lock(&sp->host->syncpt_mutex);

@@ -404,7 +395,23 @@ void host1x_syncpt_free(struct host1x_syncpt *sp)

mutex_unlock(&sp->host->syncpt_mutex);
}
-EXPORT_SYMBOL(host1x_syncpt_free);
+
+/**
+ * host1x_syncpt_put() - free a requested syncpoint
+ * @sp: host1x syncpoint
+ *
+ * Release a syncpoint previously allocated using host1x_syncpt_request(). A
+ * host1x client driver should call this when the syncpoint is no longer in
+ * use.
+ */
+void host1x_syncpt_put(struct host1x_syncpt *sp)
+{
+ if (!sp)
+ return;
+
+ kref_put(&sp->ref, syncpt_release);
+}
+EXPORT_SYMBOL(host1x_syncpt_put);

void host1x_syncpt_deinit(struct host1x *host)
{
@@ -471,16 +478,48 @@ unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
}

/**
- * host1x_syncpt_get() - obtain a syncpoint by ID
+ * host1x_syncpt_get_by_id() - obtain a syncpoint by ID
+ * @host: host1x controller
+ * @id: syncpoint ID
+ */
+struct host1x_syncpt *host1x_syncpt_get_by_id(struct host1x *host,
+ unsigned int id)
+{
+ if (id >= host->info->nb_pts)
+ return NULL;
+
+ if (kref_get_unless_zero(&host->syncpt[id].ref))
+ return &host->syncpt[id];
+ else
+ return NULL;
+}
+EXPORT_SYMBOL(host1x_syncpt_get_by_id);
+
+/**
+ * host1x_syncpt_get_by_id_noref() - obtain a syncpoint by ID but don't
+ * increase the refcount.
* @host: host1x controller
* @id: syncpoint ID
*/
-struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, unsigned int id)
+struct host1x_syncpt *host1x_syncpt_get_by_id_noref(struct host1x *host,
+ unsigned int id)
{
if (id >= host->info->nb_pts)
return NULL;

- return host->syncpt + id;
+ return &host->syncpt[id];
+}
+EXPORT_SYMBOL(host1x_syncpt_get_by_id_noref);
+
+/**
+ * host1x_syncpt_get() - increment syncpoint refcount
+ * @sp: syncpoint
+ */
+struct host1x_syncpt *host1x_syncpt_get(struct host1x_syncpt *sp)
+{
+ kref_get(&sp->ref);
+
+ return sp;
}
EXPORT_SYMBOL(host1x_syncpt_get);

diff --git a/drivers/gpu/host1x/syncpt.h b/drivers/gpu/host1x/syncpt.h
index 3aa6b25b1b9c..a6766f8d55ee 100644
--- a/drivers/gpu/host1x/syncpt.h
+++ b/drivers/gpu/host1x/syncpt.h
@@ -11,6 +11,7 @@
#include <linux/atomic.h>
#include <linux/host1x.h>
#include <linux/kernel.h>
+#include <linux/kref.h>
#include <linux/sched.h>

#include "intr.h"
@@ -26,6 +27,8 @@ struct host1x_syncpt_base {
};

struct host1x_syncpt {
+ struct kref ref;
+
unsigned int id;
atomic_t min_val;
atomic_t max_val;
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 70e1e18644b2..e14be37cdb01 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1131,8 +1131,8 @@ static void tegra_channel_host1x_syncpts_free(struct tegra_vi_channel *chan)
int i;

for (i = 0; i < chan->numgangports; i++) {
- host1x_syncpt_free(chan->mw_ack_sp[i]);
- host1x_syncpt_free(chan->frame_start_sp[i]);
+ host1x_syncpt_put(chan->mw_ack_sp[i]);
+ host1x_syncpt_put(chan->frame_start_sp[i]);
}
}

diff --git a/include/linux/host1x.h b/include/linux/host1x.h
index 7137ce0e35d4..107aea29bccb 100644
--- a/include/linux/host1x.h
+++ b/include/linux/host1x.h
@@ -142,7 +142,9 @@ struct host1x_syncpt_base;
struct host1x_syncpt;
struct host1x;

-struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, u32 id);
+struct host1x_syncpt *host1x_syncpt_get_by_id(struct host1x *host, u32 id);
+struct host1x_syncpt *host1x_syncpt_get_by_id_noref(struct host1x *host, u32 id);
+struct host1x_syncpt *host1x_syncpt_get(struct host1x_syncpt *sp);
u32 host1x_syncpt_id(struct host1x_syncpt *sp);
u32 host1x_syncpt_read_min(struct host1x_syncpt *sp);
u32 host1x_syncpt_read_max(struct host1x_syncpt *sp);
@@ -153,7 +155,7 @@ int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout,
u32 *value);
struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
unsigned long flags);
-void host1x_syncpt_free(struct host1x_syncpt *sp);
+void host1x_syncpt_put(struct host1x_syncpt *sp);
struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
unsigned long flags,
const char *name);
@@ -221,7 +223,7 @@ struct host1x_job {
dma_addr_t *reloc_addr_phys;

/* Sync point id, number of increments and end related to the submit */
- u32 syncpt_id;
+ struct host1x_syncpt *syncpt;
u32 syncpt_incrs;
u32 syncpt_end;

--
2.30.0