On Mon, Sep 18, 2023 at 2:25 PM KP Singh [off-list ref] wrote:

This helps in easily initializing blocks of code (e.g. static calls and
keys).

UNROLL(N, MACRO, __VA_ARGS__) calls MACRO N times with the first
argument as the index of the iteration. This allows string pasting to
create unique tokens for variable names, function calls etc.

As an example:

        #include <linux/unroll.h>

        #define MACRO(N, a, b)            \
                int add_##N(int a, int b) \
                {                         \
                        return a + b + N; \
                }

        UNROLL(2, MACRO, x, y)

expands to:

        int add_0(int x, int y)
        {
                return x + y + 0;
        }

        int add_1(int x, int y)
        {
                return x + y + 1;
        }

Signed-off-by: KP Singh <kpsingh@kernel.org>

Acked-by: Song Liu <song@kernel.org>