linux-stable.git/drivers/gpu/drm/i915/i915_syncmap.c, branch linux-rolling-stable

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.

As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.

Signed-off-by: Linus Torvalds

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook

drm/i915: Add flex arrays to struct i915_syncmap

2024-02-12T11:59:37+00:00

The "struct i915_syncmap" uses a dynamically sized set of trailing
elements. It can use an "u32" array or a "struct i915_syncmap *"
array.

So, use the preferred way in the kernel declaring flexible arrays [1].
Because there are two possibilities for the trailing arrays, it is
necessary to declare a union and use the DECLARE_FLEX_ARRAY macro.

The comment can be removed as the union is now clear enough.

Also, avoid the open-coded arithmetic in the memory allocator functions
[2] using the "struct_size" macro.

Moreover, refactor the "__sync_seqno" and "__sync_child" functions due
to now it is possible to use the union members added to the structure.
This way, it is also possible to avoid the open-coded arithmetic in
pointers.

Link: https://www.kernel.org/doc/html/next/process/deprecated.html#zero-length-and-one-element-arrays [1]
Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2]
Signed-off-by: Erick Archer 
Reviewed-by: Kees Cook 
Signed-off-by: Tvrtko Ursulin 
Link: https://patchwork.freedesktop.org/patch/msgid/20240208181318.4259-1-erick.archer@gmx.com

drm/i915: Convert to BITS_PER_TYPE

2018-09-26T12:32:03+00:00

In commit 9144d75e22ca ("include/linux/bitops.h: introduce BITS_PER_TYPE"),
we made BITS_PER_TYPE available to all and now we can use the macro to
replace some open-coded computation of sizeof(T) * BITS_PER_BYTE.

Suggested-by: Ville Syrjälä 
Signed-off-by: Chris Wilson 
Cc: Ville Syrjälä 
Cc: Jani Nikula 
Cc: Joonas Lahtinen 
Cc: Tvrtko Ursulin 
Reviewed-by: Jani Nikula 
Reviewed-by: Ville Syrjälä 
Link: https://patchwork.freedesktop.org/patch/msgid/20180926104707.17410-1-chris@chris-wilson.co.uk

drm/i915: Fix kerneldoc parameter markup

2018-02-08T15:08:51+00:00

drivers/gpu/drm/i915/i915_syncmap.c:92: warning: No description found for parameter 'root'
drivers/gpu/drm/i915/i915_syncmap.c:155: warning: No description found for parameter 'root'
drivers/gpu/drm/i915/i915_syncmap.c:155: warning: No description found for parameter 'id'
drivers/gpu/drm/i915/i915_syncmap.c:155: warning: No description found for parameter 'seqno'
drivers/gpu/drm/i915/i915_syncmap.c:354: warning: No description found for parameter 'root'
drivers/gpu/drm/i915/i915_syncmap.c:354: warning: No description found for parameter 'id'
drivers/gpu/drm/i915/i915_syncmap.c:354: warning: No description found for parameter 'seqno'
drivers/gpu/drm/i915/i915_syncmap.c:396: warning: No description found for parameter 'root'

Signed-off-by: Chris Wilson 
Link: https://patchwork.freedesktop.org/patch/msgid/20180208105449.29880-2-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen

drm/i915: Squash repeated awaits on the same fence

2017-05-03T10:08:48+00:00

Track the latest fence waited upon on each context, and only add a new
asynchronous wait if the new fence is more recent than the recorded
fence for that context. This requires us to filter out unordered
timelines, which are noted by DMA_FENCE_NO_CONTEXT. However, in the
absence of a universal identifier, we have to use our own
i915->mm.unordered_timeline token.

v2: Throw around the debug crutches
v3: Inline the likely case of the pre-allocation cache being full.
v4: Drop the pre-allocation support, we can lose the most recent fence
in case of allocation failure -- it just means we may emit more awaits
than strictly necessary but will not break.
v5: Trim allocation size for leaf nodes, they only need an array of u32
not pointers.
v6: Create mock_timeline to tidy selftest writing
v7: s/intel_timeline_sync_get/intel_timeline_sync_is_later/ (Tvrtko)
v8: Prune the stale sync points when we idle.
v9: Include a small benchmark in the kselftests
v10: Separate the idr implementation into its own compartment. (Tvrkto)
v11: Refactor igt_sync kselftests to avoid deep nesting (Tvrkto)
v12: __sync_leaf_idx() to assert that p->height is 0 when checking leaves
v13: kselftests to investigate struct i915_syncmap itself (Tvrtko)
v14: Foray into ascii art graphs
v15: Take into account that the random lookup/insert does 2 prng calls,
not 1, when benchmarking, and use for_each_set_bit() (Tvrtko)
v16: Improved ascii art

Signed-off-by: Chris Wilson 
Cc: Tvrtko Ursulin 
Cc: Joonas Lahtinen 
Reviewed-by: Tvrtko Ursulin 
Link: http://patchwork.freedesktop.org/patch/msgid/20170503093924.5320-4-chris@chris-wilson.co.uk