[PATCH] Uninline sys_mmap common code (reduce binary size)

This patch removes the inlinining of the new vs old mmap system
call common code.
This reduces the size of the resulting vmlinux for defconfig as follows:

mb@pc1:~/develop/git/linux-2.6$ size vmlinux.mmap*
   text    data     bss     dec     hex filename
3303749  521524  186564 4011837  3d373d vmlinux.mmapinline
3303557  521524  186564 4011645  3d367d vmlinux.mmapnoinline

The new sys_mmap2() has also one function call overhead removed, now.
(probably it was already optimized to a jmp before, but anyway...)


diff --git a/arch/i386/kernel/sys_i386.c b/arch/i386/kernel/sys_i386.c
index a4a6197..8fdb1fb 100644
--- a/arch/i386/kernel/sys_i386.c
+++ b/arch/i386/kernel/sys_i386.c
@@ -40,14 +40,13 @@ asmlinkage int sys_pipe(unsigned long __
 	return error;
 }
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
+asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
+			  unsigned long prot, unsigned long flags,
+			  unsigned long fd, unsigned long pgoff)
 {
 	int error = -EBADF;
-	struct file * file = NULL;
+	struct file *file = NULL;
+	struct mm_struct *mm = current->mm;
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 	if (!(flags & MAP_ANONYMOUS)) {
@@ -56,9 +55,9 @@ static inline long do_mmap2(
 			goto out;
 	}
 
-	down_write(&current->mm->mmap_sem);
+	down_write(&mm->mmap_sem);
 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
+	up_write(&mm->mmap_sem);
 
 	if (file)
 		fput(file);
@@ -66,13 +65,6 @@ out:
 	return error;
 }
 
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls. Linux/i386 didn't use to be able to handle more than
@@ -101,7 +93,8 @@ asmlinkage int old_mmap(struct mmap_arg_
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	err = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
+	err = sys_mmap2(a.addr, a.len, a.prot, a.flags,
+			a.fd, a.offset >> PAGE_SHIFT);
 out:
 	return err;
 }


-- 
Greetings Michael.

diff --git a/arch/i386/kernel/sys_i386.c b/arch/i386/kernel/sys_i386.c
index a4a6197..8fdb1fb 100644
--- a/arch/i386/kernel/sys_i386.c
+++ b/arch/i386/kernel/sys_i386.c
@@ -40,14 +40,13 @@ asmlinkage int sys_pipe(unsigned long __
 	return error;
 }
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
+asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
+			  unsigned long prot, unsigned long flags,
+			  unsigned long fd, unsigned long pgoff)
 {
 	int error = -EBADF;
-	struct file * file = NULL;
+	struct file *file = NULL;
+	struct mm_struct *mm = current->mm;
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 	if (!(flags & MAP_ANONYMOUS)) {
@@ -56,9 +55,9 @@ static inline long do_mmap2(
 			goto out;
 	}
 
-	down_write(&current->mm->mmap_sem);
+	down_write(&mm->mmap_sem);
 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
+	up_write(&mm->mmap_sem);
 
 	if (file)
 		fput(file);
@@ -66,13 +65,6 @@ out:
 	return error;
 }
 
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls. Linux/i386 didn't use to be able to handle more than
@@ -101,7 +93,8 @@ asmlinkage int old_mmap(struct mmap_arg_
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	err = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
+	err = sys_mmap2(a.addr, a.len, a.prot, a.flags,
+			a.fd, a.offset >> PAGE_SHIFT);
 out:
 	return err;
 }

Attachment: pgpSLy55cdn4O.pgp
Description: PGP signature

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