[Intel-gfx] [PATCH v5] drm/i915/dsb: Pre allocate and late cleanup of cmd buffer
Maarten Lankhorst
maarten.lankhorst at linux.intel.com
Fri May 8 11:14:06 UTC 2020
Op 06-05-2020 om 15:11 schreef Animesh Manna:
> Pre-allocate command buffer in atomic_commit using intel_dsb_prepare
> function which also includes pinning and map in cpu domain.
>
> No change is dsb write/commit functions.
>
> Now dsb get/put function is refactored and currently used only for
> reference counting. Below dsb api added to do respective job
> mentioned below.
>
> intel_dsb_prepare - Allocate, pin and map the buffer.
> intel_dsb_cleanup - Unpin and release the gem object.
>
> RFC: Initial patch for design review.
> v2: included _init() part in _prepare(). [Daniel, Ville]
> v3: dsb_cleanup called after cleanup_planes. [Daniel]
> v4: dsb structure is moved to intel_crtc_state from intel_crtc. [Maarten]
> v5: dsb get/put/ref-count mechanism removed. [Maarten]
>
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Jani Nikula <jani.nikula at intel.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> Signed-off-by: Animesh Manna <animesh.manna at intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_color.c | 27 ++-
> drivers/gpu/drm/i915/display/intel_display.c | 60 ++++-
> .../drm/i915/display/intel_display_types.h | 6 +-
> drivers/gpu/drm/i915/display/intel_dsb.c | 207 +++++++++---------
> drivers/gpu/drm/i915/display/intel_dsb.h | 8 +-
> 5 files changed, 178 insertions(+), 130 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
> index 98ece9cd7cdd..dba820136106 100644
> --- a/drivers/gpu/drm/i915/display/intel_color.c
> +++ b/drivers/gpu/drm/i915/display/intel_color.c
> @@ -717,7 +717,8 @@ static void bdw_load_lut_10(struct intel_crtc *crtc,
> static void ivb_load_lut_ext_max(struct intel_crtc *crtc)
> {
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> - struct intel_dsb *dsb = intel_dsb_get(crtc);
> + struct intel_crtc_state *crtc_state = to_intel_crtc_state(crtc->base.state);
> + struct intel_dsb *dsb = (struct intel_dsb *)&crtc_state->dsb;
> enum pipe pipe = crtc->pipe;
>
> /* Program the max register to clamp values > 1.0. */
Please pass the crtc_state, as crtc->state should not be used directly.
> @@ -738,8 +739,6 @@ static void ivb_load_lut_ext_max(struct intel_crtc *crtc)
> intel_dsb_reg_write(dsb, PREC_PAL_EXT2_GC_MAX(pipe, 2),
> 1 << 16);
> }
> -
> - intel_dsb_put(dsb);
> }
>
> static void ivb_load_luts(const struct intel_crtc_state *crtc_state)
> @@ -900,14 +899,13 @@ icl_load_gcmax(const struct intel_crtc_state *crtc_state,
> const struct drm_color_lut *color)
> {
> struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> - struct intel_dsb *dsb = intel_dsb_get(crtc);
> + struct intel_dsb *dsb = (struct intel_dsb *)&crtc_state->dsb;
Why the cast? Unconstify crtc_state as it's obviously not const any more.
> enum pipe pipe = crtc->pipe;
>
> /* FIXME LUT entries are 16 bit only, so we can prog 0xFFFF max */
> intel_dsb_reg_write(dsb, PREC_PAL_GC_MAX(pipe, 0), color->red);
> intel_dsb_reg_write(dsb, PREC_PAL_GC_MAX(pipe, 1), color->green);
> intel_dsb_reg_write(dsb, PREC_PAL_GC_MAX(pipe, 2), color->blue);
> - intel_dsb_put(dsb);
> }
>
> static void
> @@ -916,7 +914,7 @@ icl_program_gamma_superfine_segment(const struct intel_crtc_state *crtc_state)
> struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> const struct drm_property_blob *blob = crtc_state->hw.gamma_lut;
> const struct drm_color_lut *lut = blob->data;
> - struct intel_dsb *dsb = intel_dsb_get(crtc);
> + struct intel_dsb *dsb = (struct intel_dsb *)&crtc_state->dsb;
Same.
> enum pipe pipe = crtc->pipe;
> int i;
>
> @@ -938,8 +936,6 @@ icl_program_gamma_superfine_segment(const struct intel_crtc_state *crtc_state)
> intel_dsb_indexed_reg_write(dsb, PREC_PAL_MULTI_SEG_DATA(pipe),
> ilk_lut_12p4_udw(entry));
> }
> -
> - intel_dsb_put(dsb);
> }
>
> static void
> @@ -949,7 +945,7 @@ icl_program_gamma_multi_segment(const struct intel_crtc_state *crtc_state)
> const struct drm_property_blob *blob = crtc_state->hw.gamma_lut;
> const struct drm_color_lut *lut = blob->data;
> const struct drm_color_lut *entry;
> - struct intel_dsb *dsb = intel_dsb_get(crtc);
> + struct intel_dsb *dsb = (struct intel_dsb *)&crtc_state->dsb;
> enum pipe pipe = crtc->pipe;
> int i;
>
> @@ -996,14 +992,22 @@ icl_program_gamma_multi_segment(const struct intel_crtc_state *crtc_state)
> entry = &lut[256 * 8 * 128];
> icl_load_gcmax(crtc_state, entry);
> ivb_load_lut_ext_max(crtc);
> - intel_dsb_put(dsb);
> }
>
> static void icl_load_luts(const struct intel_crtc_state *crtc_state)
> {
> const struct drm_property_blob *gamma_lut = crtc_state->hw.gamma_lut;
> struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> - struct intel_dsb *dsb = intel_dsb_get(crtc);
> + struct intel_dsb *dsb = (struct intel_dsb *)&crtc_state->dsb;
> +
> + /*
> + * TODO: Currently dsb buffer filling is done in load_lut() which
> + * can be done much earlier, like initial stage of atomic_commit().
> + * As currently replacing the mmio-write with dsb-write so the same
> + * load_lut() api is used for dsb buffer creation which may not
> + * fit in initial stage. Need to create a separate interface and
> + * a different path in color framework while dealing with dsb.
> + */
>
> if (crtc_state->hw.degamma_lut)
> glk_load_degamma_lut(crtc_state);
> @@ -1022,7 +1026,6 @@ static void icl_load_luts(const struct intel_crtc_state *crtc_state)
> }
>
> intel_dsb_commit(dsb);
> - intel_dsb_put(dsb);
> }
>
> static u32 chv_cgm_degamma_ldw(const struct drm_color_lut *color)
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index fd6d63b03489..07670893c1ae 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -14873,8 +14873,28 @@ static int intel_atomic_check(struct drm_device *dev,
>
> static int intel_atomic_prepare_commit(struct intel_atomic_state *state)
> {
> - return drm_atomic_helper_prepare_planes(state->base.dev,
> - &state->base);
> + struct intel_crtc_state *crtc_state;
> + struct intel_crtc *crtc;
> + int i, ret;
> +
> + ret = drm_atomic_helper_prepare_planes(state->base.dev, &state->base);
> + if (ret < 0)
> + return ret;
> +
> + /*
> + * In case of DSB buffer creation failure register programming will be
> + * done by mmio and erroneous path will be handled by dsp-write api.
> + */
> + for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) {
> + bool mode_changed = needs_modeset(crtc_state);
> +
> + if (mode_changed || crtc_state->update_pipe ||
> + crtc_state->uapi.color_mgmt_changed) {
> + intel_dsb_prepare(crtc_state);
> + }
> + }
> +
> + return 0;
> }
>
> u32 intel_crtc_get_vblank_counter(struct intel_crtc *crtc)
> @@ -15327,15 +15347,39 @@ static void intel_atomic_commit_fence_wait(struct intel_atomic_state *intel_stat
> &wait_reset);
> }
>
> +static void intel_cleanup_dsbs(struct intel_atomic_state *state)
> +{
> + struct intel_crtc_state *crtc_state, *old_crtc_state, *new_crtc_state;
> + struct intel_crtc *crtc;
> + int i;
> +
> + for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
> + bool mode_changed;
> +
> + if (old_crtc_state == crtc->config)
> + crtc_state = new_crtc_state;
> + else
> + crtc_state = old_crtc_state;
> +
> + mode_changed = needs_modeset(crtc_state);
> + if (mode_changed || crtc_state->update_pipe ||
> + crtc_state->uapi.color_mgmt_changed) {
> + intel_dsb_cleanup(crtc_state);
Just call the cleanup function unconditionally here, the dsb->vma = NULL check is enough.
> + }
> + }
> +}
> +
> static void intel_atomic_cleanup_work(struct work_struct *work)
> {
> - struct drm_atomic_state *state =
> - container_of(work, struct drm_atomic_state, commit_work);
> - struct drm_i915_private *i915 = to_i915(state->dev);
> + struct intel_atomic_state *state =
> + container_of(work, struct intel_atomic_state, base.commit_work);
> + struct drm_i915_private *i915 = to_i915(state->base.dev);
>
> - drm_atomic_helper_cleanup_planes(&i915->drm, state);
> - drm_atomic_helper_commit_cleanup_done(state);
> - drm_atomic_state_put(state);
> + if (HAS_DSB(i915))
> + intel_cleanup_dsbs(state);
> + drm_atomic_helper_cleanup_planes(&i915->drm, &state->base);
> + drm_atomic_helper_commit_cleanup_done(&state->base);
> + drm_atomic_state_put(&state->base);
>
> intel_atomic_helper_free_state(i915);
> }
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 9488449e4b94..805ca774e146 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1078,6 +1078,9 @@ struct intel_crtc_state {
>
> /* Only valid on TGL+ */
> enum transcoder mst_master_transcoder;
> +
> + /* For DSB related info */
> + struct intel_dsb dsb;
> };
>
> enum intel_pipe_crc_source {
> @@ -1147,9 +1150,6 @@ struct intel_crtc {
> /* scalers available on this crtc */
> int num_scalers;
>
> - /* per pipe DSB related info */
> - struct intel_dsb dsb;
> -
> #ifdef CONFIG_DEBUG_FS
> struct intel_pipe_crc pipe_crc;
> #endif
> diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c
> index 29fec6a92d17..247fd564d394 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsb.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsb.c
> @@ -34,18 +34,22 @@
> #define DSB_BYTE_EN_SHIFT 20
> #define DSB_REG_VALUE_MASK 0xfffff
>
> -static bool is_dsb_busy(struct intel_dsb *dsb)
> +static inline bool is_dsb_busy(struct intel_dsb *dsb)
> {
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> + struct intel_crtc_state *crtc_state =
> + container_of(dsb, typeof(*crtc_state), dsb);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> enum pipe pipe = crtc->pipe;
>
> return DSB_STATUS & intel_de_read(dev_priv, DSB_CTRL(pipe, dsb->id));
> }
>
> -static bool intel_dsb_enable_engine(struct intel_dsb *dsb)
> +static inline bool intel_dsb_enable_engine(struct intel_dsb *dsb)
> {
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> + struct intel_crtc_state *crtc_state =
> + container_of(dsb, typeof(*crtc_state), dsb);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> enum pipe pipe = crtc->pipe;
> u32 dsb_ctrl;
> @@ -63,9 +67,11 @@ static bool intel_dsb_enable_engine(struct intel_dsb *dsb)
> return true;
> }
>
> -static bool intel_dsb_disable_engine(struct intel_dsb *dsb)
> +static inline bool intel_dsb_disable_engine(struct intel_dsb *dsb)
> {
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> + struct intel_crtc_state *crtc_state =
> + container_of(dsb, typeof(*crtc_state), dsb);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> enum pipe pipe = crtc->pipe;
> u32 dsb_ctrl;
> @@ -83,99 +89,6 @@ static bool intel_dsb_disable_engine(struct intel_dsb *dsb)
> return true;
> }
>
> -/**
> - * intel_dsb_get() - Allocate DSB context and return a DSB instance.
> - * @crtc: intel_crtc structure to get pipe info.
> - *
> - * This function provides handle of a DSB instance, for the further DSB
> - * operations.
> - *
> - * Returns: address of Intel_dsb instance requested for.
> - * Failure: Returns the same DSB instance, but without a command buffer.
> - */
> -
> -struct intel_dsb *
> -intel_dsb_get(struct intel_crtc *crtc)
> -{
> - struct drm_device *dev = crtc->base.dev;
> - struct drm_i915_private *i915 = to_i915(dev);
> - struct intel_dsb *dsb = &crtc->dsb;
> - struct drm_i915_gem_object *obj;
> - struct i915_vma *vma;
> - u32 *buf;
> - intel_wakeref_t wakeref;
> -
> - if (!HAS_DSB(i915))
> - return dsb;
> -
> - if (dsb->refcount++ != 0)
> - return dsb;
> -
> - wakeref = intel_runtime_pm_get(&i915->runtime_pm);
> -
> - obj = i915_gem_object_create_internal(i915, DSB_BUF_SIZE);
> - if (IS_ERR(obj)) {
> - drm_err(&i915->drm, "Gem object creation failed\n");
> - goto out;
> - }
> -
> - vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
> - if (IS_ERR(vma)) {
> - drm_err(&i915->drm, "Vma creation failed\n");
> - i915_gem_object_put(obj);
> - goto out;
> - }
> -
> - buf = i915_gem_object_pin_map(vma->obj, I915_MAP_WC);
> - if (IS_ERR(buf)) {
> - drm_err(&i915->drm, "Command buffer creation failed\n");
> - goto out;
> - }
> -
> - dsb->id = DSB1;
> - dsb->vma = vma;
> - dsb->cmd_buf = buf;
> -
> -out:
> - /*
> - * On error dsb->cmd_buf will continue to be NULL, making the writes
> - * pass-through. Leave the dangling ref to be removed later by the
> - * corresponding intel_dsb_put(): the important error message will
> - * already be logged above.
> - */
> -
> - intel_runtime_pm_put(&i915->runtime_pm, wakeref);
> -
> - return dsb;
> -}
> -
> -/**
> - * intel_dsb_put() - To destroy DSB context.
> - * @dsb: intel_dsb structure.
> - *
> - * This function destroys the DSB context allocated by a dsb_get(), by
> - * unpinning and releasing the VMA object associated with it.
> - */
> -
> -void intel_dsb_put(struct intel_dsb *dsb)
> -{
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> - struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> -
> - if (!HAS_DSB(i915))
> - return;
> -
> - if (drm_WARN_ON(&i915->drm, dsb->refcount == 0))
> - return;
> -
> - if (--dsb->refcount == 0) {
> - i915_vma_unpin_and_release(&dsb->vma, I915_VMA_RELEASE_MAP);
> - dsb->cmd_buf = NULL;
> - dsb->free_pos = 0;
> - dsb->ins_start_offset = 0;
> - }
> -}
> -
> /**
> * intel_dsb_indexed_reg_write() -Write to the DSB context for auto
> * increment register.
> @@ -192,7 +105,9 @@ void intel_dsb_put(struct intel_dsb *dsb)
> void intel_dsb_indexed_reg_write(struct intel_dsb *dsb, i915_reg_t reg,
> u32 val)
> {
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> + struct intel_crtc_state *crtc_state =
> + container_of(dsb, typeof(*crtc_state), dsb);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> u32 *buf = dsb->cmd_buf;
> u32 reg_val;
> @@ -267,7 +182,9 @@ void intel_dsb_indexed_reg_write(struct intel_dsb *dsb, i915_reg_t reg,
> */
> void intel_dsb_reg_write(struct intel_dsb *dsb, i915_reg_t reg, u32 val)
> {
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> + struct intel_crtc_state *crtc_state =
> + container_of(dsb, typeof(*crtc_state), dsb);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> u32 *buf = dsb->cmd_buf;
>
> @@ -297,7 +214,9 @@ void intel_dsb_reg_write(struct intel_dsb *dsb, i915_reg_t reg, u32 val)
> */
> void intel_dsb_commit(struct intel_dsb *dsb)
> {
> - struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb);
> + struct intel_crtc_state *crtc_state =
> + container_of(dsb, typeof(*crtc_state), dsb);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
Please pass crtc_state instead to all functions above. :)
> struct drm_device *dev = crtc->base.dev;
> struct drm_i915_private *dev_priv = to_i915(dev);
> enum pipe pipe = crtc->pipe;
> @@ -343,3 +262,87 @@ void intel_dsb_commit(struct intel_dsb *dsb)
> dsb->ins_start_offset = 0;
> intel_dsb_disable_engine(dsb);
> }
> +
> +/**
> + * intel_dsb_prepare() - Allocate, pin and map the DSB command buffer.
> + * @crtc_state: intel_crtc_state structure to prepare associated dsb instance.
> + *
> + * This function prepare the command buffer which is used to store dsb
> + * instructions with data.
> + */
> +
> +void intel_dsb_prepare(struct intel_crtc_state *crtc_state)
> +{
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> + struct intel_dsb *dsb = &crtc_state->dsb;
> + struct drm_i915_gem_object *obj;
> + struct i915_vma *vma;
> + u32 *buf;
> + intel_wakeref_t wakeref;
> +
> + if (!HAS_DSB(i915) || dsb->cmd_buf)
> + return;
> +
> + wakeref = intel_runtime_pm_get(&i915->runtime_pm);
> +
> + obj = i915_gem_object_create_internal(i915, DSB_BUF_SIZE);
> + if (IS_ERR(obj)) {
> + drm_err(&i915->drm, "Gem object creation failed\n");
> + goto out;
> + }
> +
> + vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
> + if (IS_ERR(vma)) {
> + drm_err(&i915->drm, "Vma creation failed\n");
> + i915_gem_object_put(obj);
> + goto out;
> + }
> +
> + buf = i915_gem_object_pin_map(vma->obj, I915_MAP_WC);
> + if (IS_ERR(buf)) {
> + drm_err(&i915->drm, "Command buffer creation failed\n");
> + goto out;
> + }
> +
> + dsb->id = DSB1;
> + dsb->vma = vma;
> + dsb->cmd_buf = buf;
> +
> +out:
> + /*
> + * On error dsb->cmd_buf will continue to be NULL, making the writes
> + * pass-through. Leave the dangling ref to be removed later by the
> + * corresponding intel_dsb_put(): the important error message will
> + * already be logged above.
> + */
> +
> + intel_runtime_pm_put(&i915->runtime_pm, wakeref);
> +}
> +
> +/**
> + * intel_dsb_cleanup() - To cleanup DSB context.
> + * @crtc_state: intel_crtc_state structure to cleanup associated dsb instance.
> + *
> + * This function cleanup the DSB context by unpinning and releasing
> + * the VMA object associated with it.
> + */
> +
> +void intel_dsb_cleanup(struct intel_crtc_state *crtc_state)
> +{
> + struct intel_dsb *dsb = &crtc_state->dsb;
> + struct i915_vma *p_vma;
> +
> + if (dsb->vma) {
> + p_vma = fetch_and_zero(&dsb->vma);
> + if (p_vma) {
> + i915_vma_unpin(p_vma);
> + i915_gem_object_unpin_map(p_vma->obj);
> + i915_gem_object_put(p_vma->obj);
> + }
> + dsb->vma = NULL;
> + dsb->cmd_buf = NULL;
> + dsb->free_pos = 0;
> + dsb->ins_start_offset = 0;
> + }
> +}
I would simplify cleanup to vma = fetch_and_zero(&dsb->vma); if (!vma) return; and then only call the vma/gem functions to clean up. No need to fix the other stuff here as the struct is being freed.
Could probably drop the fetch_and_zero as well, but wouldn't hurt for paranoia. :)
Otherwise looks good now, only few tweaks are needed for the patch to be ready!
~Maarten
> diff --git a/drivers/gpu/drm/i915/display/intel_dsb.h b/drivers/gpu/drm/i915/display/intel_dsb.h
> index 395ef9ce558e..3a20a4388b9a 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsb.h
> +++ b/drivers/gpu/drm/i915/display/intel_dsb.h
> @@ -10,7 +10,7 @@
>
> #include "i915_reg.h"
>
> -struct intel_crtc;
> +struct intel_crtc_state;
> struct i915_vma;
>
> enum dsb_id {
> @@ -22,7 +22,6 @@ enum dsb_id {
> };
>
> struct intel_dsb {
> - long refcount;
> enum dsb_id id;
> u32 *cmd_buf;
> struct i915_vma *vma;
> @@ -41,9 +40,8 @@ struct intel_dsb {
> u32 ins_start_offset;
> };
>
> -struct intel_dsb *
> -intel_dsb_get(struct intel_crtc *crtc);
> -void intel_dsb_put(struct intel_dsb *dsb);
> +void intel_dsb_prepare(struct intel_crtc_state *crtc_state);
> +void intel_dsb_cleanup(struct intel_crtc_state *crtc_state);
> void intel_dsb_reg_write(struct intel_dsb *dsb, i915_reg_t reg, u32 val);
> void intel_dsb_indexed_reg_write(struct intel_dsb *dsb, i915_reg_t reg,
> u32 val);
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