diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_perf.c')
-rw-r--r-- | drivers/gpu/drm/i915/i915_perf.c | 93 |
1 files changed, 37 insertions, 56 deletions
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c index 3035cba2c6a2..0a111b281578 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -531,8 +531,7 @@ static void oa_context_id_squash(struct i915_perf_stream *stream, u32 *report) * (See description of OA_TAIL_MARGIN_NSEC above for further details.) * * Besides returning true when there is data available to read() this function - * also updates the tail, aging_tail and aging_timestamp in the oa_buffer - * object. + * also updates the tail in the oa_buffer object. * * Note: It's safe to read OA config state here unlocked, assuming that this is * only called while the stream is enabled, while the global OA configuration @@ -544,10 +543,10 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream) { u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma); int report_size = stream->oa_buffer.format->size; + u32 head, tail, read_tail; unsigned long flags; bool pollin; u32 hw_tail; - u64 now; u32 partial_report_size; /* We have to consider the (unlikely) possibility that read() errors @@ -566,64 +565,48 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream) partial_report_size %= report_size; /* Subtract partial amount off the tail */ - hw_tail = gtt_offset + OA_TAKEN(hw_tail, partial_report_size); + hw_tail = OA_TAKEN(hw_tail, partial_report_size); - now = ktime_get_mono_fast_ns(); + /* NB: The head we observe here might effectively be a little + * out of date. If a read() is in progress, the head could be + * anywhere between this head and stream->oa_buffer.tail. + */ + head = stream->oa_buffer.head - gtt_offset; + read_tail = stream->oa_buffer.tail - gtt_offset; - if (hw_tail == stream->oa_buffer.aging_tail && - (now - stream->oa_buffer.aging_timestamp) > OA_TAIL_MARGIN_NSEC) { - /* If the HW tail hasn't move since the last check and the HW - * tail has been aging for long enough, declare it the new - * tail. - */ - stream->oa_buffer.tail = stream->oa_buffer.aging_tail; - } else { - u32 head, tail, aged_tail; + tail = hw_tail; - /* NB: The head we observe here might effectively be a little - * out of date. If a read() is in progress, the head could be - * anywhere between this head and stream->oa_buffer.tail. - */ - head = stream->oa_buffer.head - gtt_offset; - aged_tail = stream->oa_buffer.tail - gtt_offset; - - hw_tail -= gtt_offset; - tail = hw_tail; - - /* Walk the stream backward until we find a report with report - * id and timestmap not at 0. Since the circular buffer pointers - * progress by increments of 64 bytes and that reports can be up - * to 256 bytes long, we can't tell whether a report has fully - * landed in memory before the report id and timestamp of the - * following report have effectively landed. - * - * This is assuming that the writes of the OA unit land in - * memory in the order they were written to. - * If not : (╯°□°)╯︵ ┻━┻ - */ - while (OA_TAKEN(tail, aged_tail) >= report_size) { - void *report = stream->oa_buffer.vaddr + tail; + /* Walk the stream backward until we find a report with report + * id and timestmap not at 0. Since the circular buffer pointers + * progress by increments of 64 bytes and that reports can be up + * to 256 bytes long, we can't tell whether a report has fully + * landed in memory before the report id and timestamp of the + * following report have effectively landed. + * + * This is assuming that the writes of the OA unit land in + * memory in the order they were written to. + * If not : (╯°□°)╯︵ ┻━┻ + */ + while (OA_TAKEN(tail, read_tail) >= report_size) { + void *report = stream->oa_buffer.vaddr + tail; - if (oa_report_id(stream, report) || - oa_timestamp(stream, report)) - break; + if (oa_report_id(stream, report) || + oa_timestamp(stream, report)) + break; - tail = (tail - report_size) & (OA_BUFFER_SIZE - 1); - } + tail = (tail - report_size) & (OA_BUFFER_SIZE - 1); + } - if (OA_TAKEN(hw_tail, tail) > report_size && - __ratelimit(&stream->perf->tail_pointer_race)) - drm_notice(&stream->uncore->i915->drm, - "unlanded report(s) head=0x%x tail=0x%x hw_tail=0x%x\n", - head, tail, hw_tail); + if (OA_TAKEN(hw_tail, tail) > report_size && + __ratelimit(&stream->perf->tail_pointer_race)) + drm_notice(&stream->uncore->i915->drm, + "unlanded report(s) head=0x%x tail=0x%x hw_tail=0x%x\n", + head, tail, hw_tail); - stream->oa_buffer.tail = gtt_offset + tail; - stream->oa_buffer.aging_tail = gtt_offset + hw_tail; - stream->oa_buffer.aging_timestamp = now; - } + stream->oa_buffer.tail = gtt_offset + tail; - pollin = OA_TAKEN(stream->oa_buffer.tail - gtt_offset, - stream->oa_buffer.head - gtt_offset) >= report_size; + pollin = OA_TAKEN(stream->oa_buffer.tail, + stream->oa_buffer.head) >= report_size; spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags); @@ -1727,7 +1710,6 @@ static void gen7_init_oa_buffer(struct i915_perf_stream *stream) gtt_offset | OABUFFER_SIZE_16M); /* Mark that we need updated tail pointers to read from... */ - stream->oa_buffer.aging_tail = INVALID_TAIL_PTR; stream->oa_buffer.tail = gtt_offset; spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags); @@ -1779,7 +1761,6 @@ static void gen8_init_oa_buffer(struct i915_perf_stream *stream) intel_uncore_write(uncore, GEN8_OATAILPTR, gtt_offset & GEN8_OATAILPTR_MASK); /* Mark that we need updated tail pointers to read from... */ - stream->oa_buffer.aging_tail = INVALID_TAIL_PTR; stream->oa_buffer.tail = gtt_offset; /* @@ -1833,7 +1814,6 @@ static void gen12_init_oa_buffer(struct i915_perf_stream *stream) gtt_offset & GEN12_OAG_OATAILPTR_MASK); /* Mark that we need updated tail pointers to read from... */ - stream->oa_buffer.aging_tail = INVALID_TAIL_PTR; stream->oa_buffer.tail = gtt_offset; /* @@ -5305,6 +5285,7 @@ void i915_perf_fini(struct drm_i915_private *i915) /** * i915_perf_ioctl_version - Version of the i915-perf subsystem + * @i915: The i915 device * * This version number is used by userspace to detect available features. */ |