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Make a new directory (outside of the kernel tree) named proj01-iosched/. Copy the noop I/O scheduler source code (at block/noop-iosched.c) into the new directory, and name this copy proj01-iosched.c.

Create a new branch in your repository . Name it linux-2.6.23.17-my_syscall. As you modify the code in this branch, check your changes regularly.

Within the new branch, write a new system call function in kernel/sys.c that identifies itself and then displays the system time. Name your function sys_teamxx, replacing xx with your team number, and provide a brief description of the function.

Add a header block to proj01-iosched.c containing your team name and the names of your team members.

Change the names of the noop scheduler functions to begin with proj01 (instead of noop). Similarly, change the name of the elevator-type function.

Modify the fields of the elevator-type structure so that your functions can be recognized by the kernel. Change the elevator-name field to your team's name (e.g., team03).

Change the fields of the author and description macros appropriately.

Make a branch in your repository based on the vanilla kernel and named linux-2.6.23.17-slob_syscalls.

Within this new branch, devise a method to keep track of all of the memory claimed by the SLOB allocator for small allocations (i.e., every time the if(!b) beginning on line 331 of slob.c is entered) along with the amount of memory that was not served in an allocation request (i.e. the amount of memory contained in all blocks on the free list). Write separate system calls at the bottom of mm/slob.c to return each of these amounts in bytes and as an unsigned int, respectively called sys_get_slob_amt_claimed() and one called sys_get_slob_amt_free().

Use the program you wrote in task 4 to compare the amount of fragmentation suffered by SLOB using the first-fit algorithm and the amount suffered by SLOB using the allocation algorithm you chose to implement. Record your observations and conclusions in a README file.

Make a patch file representing the changes between your linux-2.6.23.17-xxx_fit_slob branch and the vanilla kernel. Name your patch file either

linux-2.6.23.17-best_fit_slob.patch

or

linux-2.6.23.17-worst_fit_slob.patch

depending on what allocation algorithm you implemented. Make sure this patch contains only the changes you want to submit, no experimental changes.

Make another branch in your repository based on the linux-2.6.23.17-slob_syscalls branch and name it either

linux-2.6.23.17-best_fit_slob

or

linux-2.6.23.17-worst_fit_slob

depending on what algorithm you are going to implement. Within this new branch, modify mm/slob.c so that it uses either the best-first or the worst-fit algorithm. Begin with the function slob_alloc(), and make changes elsewhere as appropriate. The changes necessary to do this should not be too significant, so if you find yourself writing many lines of code you should rethink your implementation.

Make sure you add a section to the file header including your team number, the names of your team members, and a description of the changes you made.

Append your system call to arch/i386/kernel/syscall_table.S.
Edit include/asm/unistd.h to provide your system call's number.