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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.3 (3.54.3-1.fc41) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2025-09-15 at 19:51 +0000, Frank van der Linden wrote: > In order to walk through CMA areas efficiently, it is useful > to keep a global sorted list of ranges. >=20 > Create this list when activating the areas. >=20 > Since users of this list may want to reference the CMA area > the range came from, there needs to be a link from the range > to that area. So, store a pointer to the CMA structure in > the cma_memrange structure. This also reduces the number > of arguments to a few internal functions. >=20 > Signed-off-by: Frank van der Linden >=20 > =C2=A0static int __init cma_init_reserved_areas(void) > =C2=A0{ > - int i; > + int i, r, nranges; > + struct cma *cma; > + struct cma_memrange *cmr; > + > + nranges =3D 0; > + for (i =3D 0; i < cma_area_count; i++) { > + cma =3D &cma_areas[i]; > + nranges +=3D cma->nranges; > + cma_activate_area(cma); > + } > + > + cma_ranges =3D kcalloc(nranges, sizeof(*cma_ranges), > GFP_KERNEL); > + cma_nranges =3D 0; > + for (i =3D 0; i < cma_area_count; i++) { > + cma =3D &cma_areas[i]; > + for (r =3D 0; r < cma->nranges; r++) { > + cmr =3D &cma->ranges[r]; > + cma_ranges[cma_nranges++] =3D cmr; > + } > + } > =C2=A0 > - for (i =3D 0; i < cma_area_count; i++) > - cma_activate_area(&cma_areas[i]); > + sort(cma_ranges, cma_nranges, sizeof(*cma_ranges), cmprange, > NULL); >=20 I am guessing that this is safe because cma_init_reserved_areas is an initcall, which is only called once? Is that correct? Is it worth documenting why this function creates a sorted array of CMA ranges? > =C2=A0 > =C2=A0 return 0; > =C2=A0} >=20 --=20 All Rights Reversed.