A while back, Laurent raised some comments about the component helper, which this patch set starts to address.
The first point it addresses is the repeated parsing inefficiency when deferred probing occurs. When DT is used, the structure of the component helper today means that masters end up parsing the device tree for each attempt to re-bind the driver. We remove this inefficiency by creating an array of matching data and functions, which the component helper can use internally to match up components to their master.
The second point was the inefficiency of destroying the list of components each time we saw a failure. We did this to ensure that we kept things correctly ordered: component bind order matters. As we have an array instead, the array is already ordered, so we use this array to store the component pointers instead of a list, and remember which are duplicates (and thus should be avoided.) Avoiding the right duplicates matters as we walk the array in the opposite direction at tear down.
drivers/base/component.c | 249 ++++++++++++++++++++++----------- drivers/gpu/drm/msm/msm_drv.c | 83 +++++------ drivers/staging/imx-drm/imx-drm-core.c | 57 +------- include/linux/component.h | 8 +- 4 files changed, 208 insertions(+), 189 deletions(-)