if you look into /proc/cmdline it will return to you all the kernel-parameter that are defined in your grub config. These are the parameters that are passed to the kernel at boot.

$ cat /proc/cmdline
BOOT_IMAGE=(hd0,gpt6)/vmlinuz-5.14.0-542.el9.x86_64 root=/dev/mapper/cs-root ro crashkernel=1G-4G:192M,4G-64G:256M,64G-:512M resume=/dev/mapper/cs-swap rd.lvm.lv=cs/root rd.lvm.lv=cs/swap rhgb quiet

This may be useful if you want to check for example if the system had huge-pages configured at boot time.