drm/xe/oa/uapi: Expose an unblock after N reports OA property

Expose an "unblock after N reports" OA property, to allow userspace threads
to be woken up less frequently.

Co-developed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241212224903.1853862-1-ashutosh.dixit@intel.com

diff --git a/drivers/gpu/drm/xe/xe_oa.c b/drivers/gpu/drm/xe/xe_oa.c
index ec88b18e9baa235a06af0898e51b7dd8939ab5b3..56bf375a9d4bc52faaa6fddc3cee34737afb6ef6 100644 (file)
--- a/drivers/gpu/drm/xe/xe_oa.c
+++ b/drivers/gpu/drm/xe/xe_oa.c
@@ -97,6 +97,7 @@ struct xe_oa_open_param {
        int num_syncs;
        struct xe_sync_entry *syncs;
        size_t oa_buffer_size;
+       int wait_num_reports;
 };
 
 struct xe_oa_config_bo {
@@ -241,11 +242,10 @@ static void oa_timestamp_clear(struct xe_oa_stream *stream, u32 *report)
 static bool xe_oa_buffer_check_unlocked(struct xe_oa_stream *stream)
 {
        u32 gtt_offset = xe_bo_ggtt_addr(stream->oa_buffer.bo);
+       u32 tail, hw_tail, partial_report_size, available;
        int report_size = stream->oa_buffer.format->size;
-       u32 tail, hw_tail;
        unsigned long flags;
        bool pollin;
-       u32 partial_report_size;
 
        spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
 
@@ -289,8 +289,8 @@ static bool xe_oa_buffer_check_unlocked(struct xe_oa_stream *stream)
 
        stream->oa_buffer.tail = tail;
 
-       pollin = xe_oa_circ_diff(stream, stream->oa_buffer.tail,
-                                stream->oa_buffer.head) >= report_size;
+       available = xe_oa_circ_diff(stream, stream->oa_buffer.tail, stream->oa_buffer.head);
+       pollin = available >= stream->wait_num_reports * report_size;
 
        spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
 
@@ -1285,6 +1285,17 @@ static int xe_oa_set_prop_oa_buffer_size(struct xe_oa *oa, u64 value,
        return 0;
 }
 
+static int xe_oa_set_prop_wait_num_reports(struct xe_oa *oa, u64 value,
+                                          struct xe_oa_open_param *param)
+{
+       if (!value) {
+               drm_dbg(&oa->xe->drm, "wait_num_reports %llu\n", value);
+               return -EINVAL;
+       }
+       param->wait_num_reports = value;
+       return 0;
+}
+
 static int xe_oa_set_prop_ret_inval(struct xe_oa *oa, u64 value,
                                    struct xe_oa_open_param *param)
 {
@@ -1306,6 +1317,7 @@ static const xe_oa_set_property_fn xe_oa_set_property_funcs_open[] = {
        [DRM_XE_OA_PROPERTY_NUM_SYNCS] = xe_oa_set_prop_num_syncs,
        [DRM_XE_OA_PROPERTY_SYNCS] = xe_oa_set_prop_syncs_user,
        [DRM_XE_OA_PROPERTY_OA_BUFFER_SIZE] = xe_oa_set_prop_oa_buffer_size,
+       [DRM_XE_OA_PROPERTY_WAIT_NUM_REPORTS] = xe_oa_set_prop_wait_num_reports,
 };
 
 static const xe_oa_set_property_fn xe_oa_set_property_funcs_config[] = {
@@ -1321,6 +1333,7 @@ static const xe_oa_set_property_fn xe_oa_set_property_funcs_config[] = {
        [DRM_XE_OA_PROPERTY_NUM_SYNCS] = xe_oa_set_prop_num_syncs,
        [DRM_XE_OA_PROPERTY_SYNCS] = xe_oa_set_prop_syncs_user,
        [DRM_XE_OA_PROPERTY_OA_BUFFER_SIZE] = xe_oa_set_prop_ret_inval,
+       [DRM_XE_OA_PROPERTY_WAIT_NUM_REPORTS] = xe_oa_set_prop_ret_inval,
 };
 
 static int xe_oa_user_ext_set_property(struct xe_oa *oa, enum xe_oa_user_extn_from from,
@@ -1797,6 +1810,7 @@ static int xe_oa_stream_init(struct xe_oa_stream *stream,
        stream->periodic = param->period_exponent > 0;
        stream->period_exponent = param->period_exponent;
        stream->no_preempt = param->no_preempt;
+       stream->wait_num_reports = param->wait_num_reports;
 
        stream->xef = xe_file_get(param->xef);
        stream->num_syncs = param->num_syncs;
@@ -2156,6 +2170,14 @@ int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *f
        if (!param.oa_buffer_size)
                param.oa_buffer_size = DEFAULT_XE_OA_BUFFER_SIZE;
 
+       if (!param.wait_num_reports)
+               param.wait_num_reports = 1;
+       if (param.wait_num_reports > param.oa_buffer_size / f->size) {
+               drm_dbg(&oa->xe->drm, "wait_num_reports %d\n", param.wait_num_reports);
+               ret = -EINVAL;
+               goto err_exec_q;
+       }
+
        ret = xe_oa_parse_syncs(oa, &param);
        if (ret)
                goto err_exec_q;

diff --git a/drivers/gpu/drm/xe/xe_oa_types.h b/drivers/gpu/drm/xe/xe_oa_types.h
index df77939156288483dcc23b217b0e1708a9130370..2dcd3b9562e977a7470e2d06b13203f421b8994b 100644 (file)
--- a/drivers/gpu/drm/xe/xe_oa_types.h
+++ b/drivers/gpu/drm/xe/xe_oa_types.h
@@ -218,6 +218,9 @@ struct xe_oa_stream {
        /** @pollin: Whether there is data available to read */
        bool pollin;
 
+       /** @wait_num_reports: Number of reports to wait for before signalling pollin */
+       int wait_num_reports;
+
        /** @periodic: Whether periodic sampling is currently enabled */
        bool periodic;
 

diff --git a/drivers/gpu/drm/xe/xe_query.c b/drivers/gpu/drm/xe/xe_query.c
index d2a816f71bf26af50f25c3dc0cb7303a7cb2c19b..c059639613f7b548c168f808b7b7b354f1cf3c94 100644 (file)
--- a/drivers/gpu/drm/xe/xe_query.c
+++ b/drivers/gpu/drm/xe/xe_query.c
@@ -672,7 +672,8 @@ static int query_oa_units(struct xe_device *xe,
                        du->oa_unit_type = u->type;
                        du->oa_timestamp_freq = xe_oa_timestamp_frequency(gt);
                        du->capabilities = DRM_XE_OA_CAPS_BASE | DRM_XE_OA_CAPS_SYNCS |
-                                          DRM_XE_OA_CAPS_OA_BUFFER_SIZE;
+                                          DRM_XE_OA_CAPS_OA_BUFFER_SIZE |
+                                          DRM_XE_OA_CAPS_WAIT_NUM_REPORTS;
 
                        j = 0;
                        for_each_hw_engine(hwe, gt, hwe_id) {

diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index 0383b52cbd8699869f76b279019ffce530e1df76..f62689ca861a4673b885629460c11d6f3bc6523d 100644 (file)
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -1487,6 +1487,7 @@ struct drm_xe_oa_unit {
 #define DRM_XE_OA_CAPS_BASE            (1 << 0)
 #define DRM_XE_OA_CAPS_SYNCS           (1 << 1)
 #define DRM_XE_OA_CAPS_OA_BUFFER_SIZE  (1 << 2)
+#define DRM_XE_OA_CAPS_WAIT_NUM_REPORTS        (1 << 3)
 
        /** @oa_timestamp_freq: OA timestamp freq */
        __u64 oa_timestamp_freq;
@@ -1660,6 +1661,12 @@ enum drm_xe_oa_property_id {
         * buffer is allocated by default.
         */
        DRM_XE_OA_PROPERTY_OA_BUFFER_SIZE,
+
+       /**
+        * @DRM_XE_OA_PROPERTY_WAIT_NUM_REPORTS: Number of reports to wait
+        * for before unblocking poll or read
+        */
+       DRM_XE_OA_PROPERTY_WAIT_NUM_REPORTS,
 };
 
 /**