On 08.09.25 19:05, Alex Hung wrote:
>
>
> On 8/24/25 12:23, Kuan-Wei Chiu wrote:
>> Replace the custom bubble sort used for sorting reserved time
>> candidates in with the kernel's standard sort() helper. The previous
>> code had O(N^2) time complexity, while the generic kernel sort runs in
>> O(N log N). This improves efficiency and removes the need for a local
>> sorting implementation, while keeping functionality unchanged.
>>
>> Signed-off-by: Kuan-Wei Chiu <[email protected]>
>> ---
>> Compile test only.
>>
>> .../dml2/dml21/src/dml2_pmo/dml2_pmo_dcn3.c | 23 +++++++++++--------
>> 1 file changed, 13 insertions(+), 10 deletions(-)
>>
>> diff --git
>> a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_pmo/dml2_pmo_dcn3.c
>> b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_pmo/dml2_pmo_dcn3.c
>> index e763c8e45da8..2b13a5e88917 100644
>> --- a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_pmo/dml2_pmo_dcn3.c
>> +++ b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_pmo/dml2_pmo_dcn3.c
>> @@ -2,19 +2,21 @@
>> //
>> // Copyright 2024 Advanced Micro Devices, Inc.
>> +#include <linux/sort.h>
>> +
>
> Thanks for working on this, but this file is shared with another OS and it is
> not possible to replace sort function with Linux-only sort.
That's not a valid argument. Linux code must be solely written for Linux, you
can't reject a valid patch because it breaks sharing code with other operating
systems.
Regards,
Christian.
>
>> #include "dml2_pmo_factory.h"
>> #include "dml2_pmo_dcn3.h"
>> -static void sort(double *list_a, int list_a_size)
>> +static int cmp_double(const void *a, const void *b)
>> {
>> - // For all elements b[i] in list_b[]
>> - for (int i = 0; i < list_a_size - 1; i++) {
>> - // Find the first element of list_a that's larger than b[i]
>> - for (int j = i; j < list_a_size - 1; j++) {
>> - if (list_a[j] > list_a[j + 1])
>> - swap(list_a[j], list_a[j + 1]);
>> - }
>> - }
>> + double da = *(const double *)a;
>> + double db = *(const double *)b;
>> +
>> + if (da < db)
>> + return -1;
>> + if (da > db)
>> + return 1;
>> + return 0;
>> }
>> static double
>> get_max_reserved_time_on_all_planes_with_stream_index(struct
>> display_configuation_with_meta *config, unsigned int stream_index)
>> @@ -634,7 +636,8 @@ bool pmo_dcn3_init_for_pstate_support(struct
>> dml2_pmo_init_for_pstate_support_in
>> // Finally sort the array of candidates
>> sort(pmo->scratch.pmo_dcn3.reserved_time_candidates[stream_index],
>> -
>> pmo->scratch.pmo_dcn3.reserved_time_candidates_count[stream_index]);
>> +
>> pmo->scratch.pmo_dcn3.reserved_time_candidates_count[stream_index],
>> + sizeof(double), cmp_double, NULL);
>>
>> remove_duplicates(pmo->scratch.pmo_dcn3.reserved_time_candidates[stream_index],
>>
>> &pmo->scratch.pmo_dcn3.reserved_time_candidates_count[stream_index]);
>
