Allow linker to eliminate unused functions in lib/*

PATCH In review Andi Kleen 4 participants 9 messages Jan 5, 2010 – Jan 16, 2010

Subsystems (4)

Networking Library code Bitmap API Generic string library

lore

Share & tools

lore

Andi Kleen

author

2010-01-05 14:59 UTC #0 lore raw

PATCH 1/1 Allow linker to eliminate unused functions in lib/*

Allow linker to eliminate unused functions in lib/*

Right now a lot of code in lib/* is obj-y and always linked in. The reason is that there is no other way to ensure the EXPORT_SYMBOLs get included.

This patch moves the EXPORT_SYMBOLs into separate files instead. This way the files actually implementing the code can be made lib-y again, and the separate export symbols pull them in for modular kernels.

For non modular kernels the linker can decide whether to use them or not.

This shrinks a allnoconfig+CONFIG_EMBEDDED=y+all options disabled kernel by about 1k on x86. Not much, but also not too shabby.

In some ways that's similar to the old ksyms.c files, but not as centralized.

I didn't do this for the functions in lib/* which already have Kconfig symbol. Presumably that is usually only set on demand when they are actually needed (although I'm not sure it's true for all cases).

Signed-off-by Andi Kleen <[email protected]>

---
 lib/Makefile         |    8 +++++++-
 lib/bcd.c            |    3 ---
 lib/bitmap.c         |   34 ++++------------------------------
 lib/debug_locks.c    |    1 -
 lib/div64.c          |    7 +------
 lib/gcd.c            |    3 +--
 lib/halfmd4.c        |    3 +--
 lib/hexdump.c        |    5 -----
 lib/kasprintf.c      |    6 +++---
 lib/lib-syms.c       |   37 ++++++++++++++++++++++++++++++++++++-
 lib/parser.c         |    9 +--------
 lib/random32.c       |    3 ---
 lib/scatterlist.c    |   19 +++++--------------
 lib/sort.c           |    2 --
 lib/string_helpers.c |    3 +--
 15 files changed, 60 insertions(+), 83 deletions(-)

lib/Makefile +7 -1

Index: linux-2.6.33-rc2-ak/lib/Makefile
===================================================================
@@ -7,6 +7,10 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
 endif
 
+# Please put EXPORT_SYMBOLs into lib-syms.c or an own file (and make
+# only that obj-y), not into the files directly.
+# This way the linker can eliminate unneeded code on non modular kernels.
+
 lib-y := ctype.o string.o vsprintf.o cmdline.o \
 	 rbtree.o radix-tree.o dump_stack.o \
 	 idr.o int_sqrt.o extable.o prio_tree.o \

@@ -19,10 +23,12 @@ lib-$(CONFIG_SMP) += cpumask.o
 
 lib-y	+= kobject.o kref.o klist.o
 
-obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
+lib-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
 	 string_helpers.o gcd.o
 
+obj-y += bitmap-syms.o lib-syms.o scatterlist-syms.o
+
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
 CFLAGS_kobject_uevent.o += -DDEBUG

lib/bcd.c +0 -3

Index: linux-2.6.33-rc2-ak/lib/bcd.c
===================================================================
@@ -1,14 +1,11 @@
 #include <linux/bcd.h>
-#include <linux/module.h>
 
 unsigned bcd2bin(unsigned char val)
 {
 	return (val & 0x0f) + (val >> 4) * 10;
 }
-EXPORT_SYMBOL(bcd2bin);
 
 unsigned char bin2bcd(unsigned val)
 {
 	return ((val / 10) << 4) + val % 10;
 }
-EXPORT_SYMBOL(bin2bcd);

lib/bitmap.c +4 ~~-30~~

Index: linux-2.6.33-rc2-ak/lib/bitmap.c
===================================================================
@@ -5,7 +5,6 @@
  * This source code is licensed under the GNU General Public License,
  * Version 2.  See the file COPYING for more details.
  */
-#include <linux/module.h>
 #include <linux/ctype.h>
 #include <linux/errno.h>
 #include <linux/bitmap.h>

@@ -13,6 +12,10 @@
 #include <asm/uaccess.h>
 
 /*
+ * Please put EXPORT_SYMBOLs into bitmap-syms.c
+ */
+
+/*
  * bitmaps provide an array of bits, implemented using an an
  * array of unsigned longs.  The number of valid bits in a
  * given bitmap does _not_ need to be an exact multiple of

@@ -51,7 +54,6 @@ int __bitmap_empty(const unsigned long *
 
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_empty);
 
 int __bitmap_full(const unsigned long *bitmap, int bits)
 {

@@ -66,7 +68,6 @@ int __bitmap_full(const unsigned long *b
 
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_full);
 
 int __bitmap_equal(const unsigned long *bitmap1,
 		const unsigned long *bitmap2, int bits)

@@ -82,7 +83,6 @@ int __bitmap_equal(const unsigned long *
 
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_equal);
 
 void __bitmap_complement(unsigned long *dst, const unsigned long *src, int bits)
 {

@@ -93,7 +93,6 @@ void __bitmap_complement(unsigned long *
 	if (bits % BITS_PER_LONG)
 		dst[k] = ~src[k] & BITMAP_LAST_WORD_MASK(bits);
 }
-EXPORT_SYMBOL(__bitmap_complement);
 
 /**
  * __bitmap_shift_right - logical right shift of the bits in a bitmap

@@ -136,7 +135,6 @@ void __bitmap_shift_right(unsigned long
 	if (off)
 		memset(&dst[lim - off], 0, off*sizeof(unsigned long));
 }
-EXPORT_SYMBOL(__bitmap_shift_right);
 
 
 /**

@@ -177,7 +175,6 @@ void __bitmap_shift_left(unsigned long *
 	if (off)
 		memset(dst, 0, off*sizeof(unsigned long));
 }
-EXPORT_SYMBOL(__bitmap_shift_left);
 
 int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -190,7 +187,6 @@ int __bitmap_and(unsigned long *dst, con
 		result |= (dst[k] = bitmap1[k] & bitmap2[k]);
 	return result != 0;
 }
-EXPORT_SYMBOL(__bitmap_and);
 
 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -201,7 +197,6 @@ void __bitmap_or(unsigned long *dst, con
 	for (k = 0; k < nr; k++)
 		dst[k] = bitmap1[k] | bitmap2[k];
 }
-EXPORT_SYMBOL(__bitmap_or);
 
 void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -212,7 +207,6 @@ void __bitmap_xor(unsigned long *dst, co
 	for (k = 0; k < nr; k++)
 		dst[k] = bitmap1[k] ^ bitmap2[k];
 }
-EXPORT_SYMBOL(__bitmap_xor);
 
 int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -225,7 +219,6 @@ int __bitmap_andnot(unsigned long *dst,
 		result |= (dst[k] = bitmap1[k] & ~bitmap2[k]);
 	return result != 0;
 }
-EXPORT_SYMBOL(__bitmap_andnot);
 
 int __bitmap_intersects(const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -240,7 +233,6 @@ int __bitmap_intersects(const unsigned l
 			return 1;
 	return 0;
 }
-EXPORT_SYMBOL(__bitmap_intersects);
 
 int __bitmap_subset(const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -255,7 +247,6 @@ int __bitmap_subset(const unsigned long
 			return 0;
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_subset);
 
 int __bitmap_weight(const unsigned long *bitmap, int bits)
 {

@@ -269,7 +260,6 @@ int __bitmap_weight(const unsigned long
 
 	return w;
 }
-EXPORT_SYMBOL(__bitmap_weight);
 
 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))

@@ -292,7 +282,6 @@ void bitmap_set(unsigned long *map, int
 		*p |= mask_to_set;
 	}
 }
-EXPORT_SYMBOL(bitmap_set);
 
 void bitmap_clear(unsigned long *map, int start, int nr)
 {

@@ -313,7 +302,6 @@ void bitmap_clear(unsigned long *map, in
 		*p &= ~mask_to_clear;
 	}
 }
-EXPORT_SYMBOL(bitmap_clear);
 
 /*
  * bitmap_find_next_zero_area - find a contiguous aligned zero area

@@ -350,7 +338,6 @@ again:
 	}
 	return index;
 }
-EXPORT_SYMBOL(bitmap_find_next_zero_area);
 
 /*
  * Bitmap printing & parsing functions: first version by Bill Irwin,

@@ -398,7 +385,6 @@ int bitmap_scnprintf(char *buf, unsigned
 	}
 	return len;
 }
-EXPORT_SYMBOL(bitmap_scnprintf);
 
 /**
  * __bitmap_parse - convert an ASCII hex string into a bitmap.

@@ -484,7 +470,6 @@ int __bitmap_parse(const char *buf, unsi
 
 	return 0;
 }
-EXPORT_SYMBOL(__bitmap_parse);
 
 /**
  * bitmap_parse_user()

@@ -509,7 +494,6 @@ int bitmap_parse_user(const char __user
 		return -EFAULT;
 	return __bitmap_parse((const char *)ubuf, ulen, 1, maskp, nmaskbits);
 }
-EXPORT_SYMBOL(bitmap_parse_user);
 
 /*
  * bscnl_emit(buf, buflen, rbot, rtop, bp)

@@ -569,7 +553,6 @@ int bitmap_scnlistprintf(char *buf, unsi
 	}
 	return len;
 }
-EXPORT_SYMBOL(bitmap_scnlistprintf);
 
 /**
  * bitmap_parselist - convert list format ASCII string to bitmap

@@ -616,7 +599,6 @@ int bitmap_parselist(const char *bp, uns
 	} while (*bp != '\0' && *bp != '\n');
 	return 0;
 }
-EXPORT_SYMBOL(bitmap_parselist);
 
 /**
  * bitmap_pos_to_ord(buf, pos, bits)

@@ -743,7 +725,6 @@ void bitmap_remap(unsigned long *dst, co
 			set_bit(bitmap_ord_to_pos(new, n % w, bits), dst);
 	}
 }
-EXPORT_SYMBOL(bitmap_remap);
 
 /**
  * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit

@@ -781,7 +762,6 @@ int bitmap_bitremap(int oldbit, const un
 	else
 		return bitmap_ord_to_pos(new, n % w, bits);
 }
-EXPORT_SYMBOL(bitmap_bitremap);
 
 /**
  * bitmap_onto - translate one bitmap relative to another

@@ -912,7 +892,6 @@ void bitmap_onto(unsigned long *dst, con
 		m++;
 	}
 }
-EXPORT_SYMBOL(bitmap_onto);
 
 /**
  * bitmap_fold - fold larger bitmap into smaller, modulo specified size

@@ -939,7 +918,6 @@ void bitmap_fold(unsigned long *dst, con
 	     oldbit = find_next_bit(orig, bits, oldbit + 1))
 		set_bit(oldbit % sz, dst);
 }
-EXPORT_SYMBOL(bitmap_fold);
 
 /*
  * Common code for bitmap_*_region() routines.

@@ -1043,7 +1021,6 @@ int bitmap_find_free_region(unsigned lon
 	}
 	return -ENOMEM;
 }
-EXPORT_SYMBOL(bitmap_find_free_region);
 
 /**
  * bitmap_release_region - release allocated bitmap region

@@ -1060,7 +1037,6 @@ void bitmap_release_region(unsigned long
 {
 	__reg_op(bitmap, pos, order, REG_OP_RELEASE);
 }
-EXPORT_SYMBOL(bitmap_release_region);
 
 /**
  * bitmap_allocate_region - allocate bitmap region

@@ -1080,7 +1056,6 @@ int bitmap_allocate_region(unsigned long
 	__reg_op(bitmap, pos, order, REG_OP_ALLOC);
 	return 0;
 }
-EXPORT_SYMBOL(bitmap_allocate_region);
 
 /**
  * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order.

@@ -1102,4 +1077,3 @@ void bitmap_copy_le(void *dst, const uns
 			d[i] = cpu_to_le32(src[i]);
 	}
 }
-EXPORT_SYMBOL(bitmap_copy_le);

lib/debug_locks.c +0 -1

Index: linux-2.6.33-rc2-ak/lib/debug_locks.c
===================================================================
@@ -11,7 +11,6 @@
 #include <linux/kernel.h>
 #include <linux/rwsem.h>
 #include <linux/mutex.h>
-#include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/debug_locks.h>

lib/div64.c +1 -6

Index: linux-2.6.33-rc2-ak/lib/div64.c
===================================================================
@@ -16,7 +16,6 @@
  * assembly versions such as arch/ppc/lib/div64.S and arch/sh/lib/div64.S.
  */
 
-#include <linux/module.h>
 #include <linux/math64.h>
 
 /* Not needed on 64bit architectures */

@@ -55,8 +54,6 @@ uint32_t __attribute__((weak)) __div64_3
 	return rem;
 }
 
-EXPORT_SYMBOL(__div64_32);
-
 #ifndef div_s64_rem
 s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
 {

@@ -74,7 +71,6 @@ s64 div_s64_rem(s64 dividend, s32 diviso
 	}
 	return quotient;
 }
-EXPORT_SYMBOL(div_s64_rem);
 #endif
 
 /* 64bit divisor, dividend and result. dynamic precision */

@@ -94,7 +90,6 @@ u64 div64_u64(u64 dividend, u64 divisor)
 
 	return div_u64(dividend, d);
 }
-EXPORT_SYMBOL(div64_u64);
 #endif
 
 #endif /* BITS_PER_LONG == 32 */

@@ -107,4 +102,4 @@ u32 iter_div_u64_rem(u64 dividend, u32 d
 {
 	return __iter_div_u64_rem(dividend, divisor, remainder);
 }
-EXPORT_SYMBOL(iter_div_u64_rem);
+

lib/gcd.c +1 -2

Index: linux-2.6.33-rc2-ak/lib/gcd.c
===================================================================
@@ -1,6 +1,5 @@
 #include <linux/kernel.h>
 #include <linux/gcd.h>
-#include <linux/module.h>
 
 /* Greatest common divisor */
 unsigned long gcd(unsigned long a, unsigned long b)

@@ -15,4 +14,4 @@ unsigned long gcd(unsigned long a, unsig
 	}
 	return b;
 }
-EXPORT_SYMBOL_GPL(gcd);
+

lib/halfmd4.c +1 -2

Index: linux-2.6.33-rc2-ak/lib/halfmd4.c
===================================================================
@@ -1,5 +1,4 @@
 #include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/cryptohash.h>
 
 /* F, G and H are basic MD4 functions: selection, majority, parity */

@@ -63,4 +62,4 @@ __u32 half_md4_transform(__u32 buf[4], _
 
 	return buf[1]; /* "most hashed" word */
 }
-EXPORT_SYMBOL(half_md4_transform);
+

lib/hexdump.c +0 -5

Index: linux-2.6.33-rc2-ak/lib/hexdump.c
===================================================================
@@ -10,10 +10,8 @@
 #include <linux/types.h>
 #include <linux/ctype.h>
 #include <linux/kernel.h>
-#include <linux/module.h>
 
 const char hex_asc[] = "0123456789abcdef";
-EXPORT_SYMBOL(hex_asc);
 
 /**
  * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory

@@ -117,7 +115,6 @@ void hex_dump_to_buffer(const void *buf,
 nil:
 	linebuf[lx++] = '\0';
 }
-EXPORT_SYMBOL(hex_dump_to_buffer);
 
 /**
  * print_hex_dump - print a text hex dump to syslog for a binary blob of data

@@ -181,7 +178,6 @@ void print_hex_dump(const char *level, c
 		}
 	}
 }
-EXPORT_SYMBOL(print_hex_dump);
 
 /**
  * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params

@@ -201,4 +197,3 @@ void print_hex_dump_bytes(const char *pr
 	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1,
 			buf, len, 1);
 }
-EXPORT_SYMBOL(print_hex_dump_bytes);

lib/kasprintf.c +3 -3

Index: linux-2.6.33-rc2-ak/lib/kasprintf.c
===================================================================
@@ -5,9 +5,10 @@
  */
 
 #include <stdarg.h>
-#include <linux/module.h>
 #include <linux/types.h>
 #include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
 
 /* Simplified asprintf. */
 char *kvasprintf(gfp_t gfp, const char *fmt, va_list ap)

@@ -28,7 +29,6 @@ char *kvasprintf(gfp_t gfp, const char *
 
 	return p;
 }
-EXPORT_SYMBOL(kvasprintf);
 
 char *kasprintf(gfp_t gfp, const char *fmt, ...)
 {

@@ -41,4 +41,4 @@ char *kasprintf(gfp_t gfp, const char *f
 
 	return p;
 }
-EXPORT_SYMBOL(kasprintf);
+

lib/parser.c +1 -8

Index: linux-2.6.33-rc2-ak/lib/parser.c
===================================================================
@@ -5,8 +5,8 @@
  * Version 2.  See the file COPYING for more details.
  */
 
+#include <linux/types.h>
 #include <linux/ctype.h>
-#include <linux/module.h>
 #include <linux/parser.h>
 #include <linux/slab.h>
 #include <linux/string.h>

@@ -222,10 +222,3 @@ char *match_strdup(const substring_t *s)
 		match_strlcpy(p, s, sz);
 	return p;
 }
-
-EXPORT_SYMBOL(match_token);
-EXPORT_SYMBOL(match_int);
-EXPORT_SYMBOL(match_octal);
-EXPORT_SYMBOL(match_hex);
-EXPORT_SYMBOL(match_strlcpy);
-EXPORT_SYMBOL(match_strdup);

lib/random32.c +0 -3

Index: linux-2.6.33-rc2-ak/lib/random32.c
===================================================================
@@ -35,7 +35,6 @@
 
 #include <linux/types.h>
 #include <linux/percpu.h>
-#include <linux/module.h>
 #include <linux/jiffies.h>
 #include <linux/random.h>

@@ -79,7 +78,6 @@ u32 random32(void)
 	put_cpu_var(state);
 	return r;
 }
-EXPORT_SYMBOL(random32);
 
 /**
  *	srandom32 - add entropy to pseudo random number generator

@@ -99,7 +97,6 @@ void srandom32(u32 entropy)
 		state->s1 = __seed(state->s1 ^ entropy, 1);
 	}
 }
-EXPORT_SYMBOL(srandom32);
 
 /*
  *	Generate some initially weak seeding values to allow

lib/scatterlist.c +5 ~~-14~~

Index: linux-2.6.33-rc2-ak/lib/scatterlist.c
===================================================================
@@ -6,10 +6,13 @@
  * This source code is licensed under the GNU General Public License,
  * Version 2. See the file COPYING for more details.
  */
-#include <linux/module.h>
 #include <linux/scatterlist.h>
 #include <linux/highmem.h>
 
+/*
+ * Please put EXPORT_SYMBOLs into scatterlist-syms.c
+ */
+
 /**
  * sg_next - return the next scatterlist entry in a list
  * @sg:		The current sg entry

@@ -34,7 +37,6 @@ struct scatterlist *sg_next(struct scatt
 
 	return sg;
 }
-EXPORT_SYMBOL(sg_next);
 
 /**
  * sg_last - return the last scatterlist entry in a list

@@ -68,7 +70,6 @@ struct scatterlist *sg_last(struct scatt
 #endif
 	return ret;
 }
-EXPORT_SYMBOL(sg_last);
 
 /**
  * sg_init_table - Initialize SG table

@@ -92,7 +93,6 @@ void sg_init_table(struct scatterlist *s
 #endif
 	sg_mark_end(&sgl[nents - 1]);
 }
-EXPORT_SYMBOL(sg_init_table);
 
 /**
  * sg_init_one - Initialize a single entry sg list

@@ -106,7 +106,6 @@ void sg_init_one(struct scatterlist *sg,
 	sg_init_table(sg, 1);
 	sg_set_buf(sg, buf, buflen);
 }
-EXPORT_SYMBOL(sg_init_one);
 
 /*
  * The default behaviour of sg_alloc_table() is to use these kmalloc/kfree

@@ -175,7 +174,6 @@ void __sg_free_table(struct sg_table *ta
 
 	table->sgl = NULL;
 }
-EXPORT_SYMBOL(__sg_free_table);
 
 /**
  * sg_free_table - Free a previously allocated sg table

@@ -186,7 +184,6 @@ void sg_free_table(struct sg_table *tabl
 {
 	__sg_free_table(table, SG_MAX_SINGLE_ALLOC, sg_kfree);
 }
-EXPORT_SYMBOL(sg_free_table);
 
 /**
  * __sg_alloc_table - Allocate and initialize an sg table with given allocator

@@ -268,7 +265,6 @@ int __sg_alloc_table(struct sg_table *ta
 
 	return 0;
 }
-EXPORT_SYMBOL(__sg_alloc_table);
 
 /**
  * sg_alloc_table - Allocate and initialize an sg table

@@ -292,7 +288,6 @@ int sg_alloc_table(struct sg_table *tabl
 
 	return ret;
 }
-EXPORT_SYMBOL(sg_alloc_table);
 
 /**
  * sg_miter_start - start mapping iteration over a sg list

@@ -317,7 +312,6 @@ void sg_miter_start(struct sg_mapping_it
 	WARN_ON(!(flags & (SG_MITER_TO_SG | SG_MITER_FROM_SG)));
 	miter->__flags = flags;
 }
-EXPORT_SYMBOL(sg_miter_start);
 
 /**
  * sg_miter_next - proceed mapping iterator to the next mapping

@@ -372,7 +366,6 @@ bool sg_miter_next(struct sg_mapping_ite
 
 	return true;
 }
-EXPORT_SYMBOL(sg_miter_next);
 
 /**
  * sg_miter_stop - stop mapping iteration

@@ -410,7 +403,6 @@ void sg_miter_stop(struct sg_mapping_ite
 		miter->consumed = 0;
 	}
 }
-EXPORT_SYMBOL(sg_miter_stop);
 
 /**
  * sg_copy_buffer - Copy data between a linear buffer and an SG list

@@ -475,7 +467,6 @@ size_t sg_copy_from_buffer(struct scatte
 {
 	return sg_copy_buffer(sgl, nents, buf, buflen, 0);
 }
-EXPORT_SYMBOL(sg_copy_from_buffer);
 
 /**
  * sg_copy_to_buffer - Copy from an SG list to a linear buffer

@@ -492,4 +483,4 @@ size_t sg_copy_to_buffer(struct scatterl
 {
 	return sg_copy_buffer(sgl, nents, buf, buflen, 1);
 }
-EXPORT_SYMBOL(sg_copy_to_buffer);
+

lib/sort.c +0 -2

Index: linux-2.6.33-rc2-ak/lib/sort.c
===================================================================
@@ -87,8 +87,6 @@ void sort(void *base, size_t num, size_t
 	}
 }
 
-EXPORT_SYMBOL(sort);
-
 #if 0
 /* a simple boot-time regression test */

lib/string_helpers.c +1 -2

Index: linux-2.6.33-rc2-ak/lib/string_helpers.c
===================================================================
@@ -5,7 +5,6 @@
  */
 #include <linux/kernel.h>
 #include <linux/math64.h>
-#include <linux/module.h>
 #include <linux/string_helpers.h>
 
 /**

@@ -65,4 +64,4 @@ int string_get_size(u64 size, const enum
 
 	return 0;
 }
-EXPORT_SYMBOL(string_get_size);
+

lib/lib-syms.c +36 -1

Index: linux-2.6.33-rc2-ak/lib/lib-syms.c
===================================================================
@@ -5,9 +5,13 @@
  * On modular kernels it keeps a reference to all the lib files with
  * exports so that they can be used by modules.  On non modular
  * kernels it does nothing and the linker can decide whether a lib
- * object file is needed or not.
+ * object file is needed or not. This way unneeded library functions
+ * can be eliminated.
  */
 
+#include <linux/types.h>
+#include <linux/module.h>
+
 #include <linux/bcd.h>
 EXPORT_SYMBOL(bcd2bin);
 EXPORT_SYMBOL(bin2bcd);

@@ -24,4 +28,35 @@ EXPORT_SYMBOL(div64_u64);
 #endif
 EXPORT_SYMBOL(iter_div_u64_rem);
 
+#include <linux/sort.h>
+EXPORT_SYMBOL(sort);
+
+#include <linux/parser.h>
+EXPORT_SYMBOL(match_token);
+EXPORT_SYMBOL(match_int);
+EXPORT_SYMBOL(match_octal);
+EXPORT_SYMBOL(match_hex);
+EXPORT_SYMBOL(match_strlcpy);
+EXPORT_SYMBOL(match_strdup);
+
+#include <linux/cryptohash.h>
+EXPORT_SYMBOL(half_md4_transform);
+
+#include <linux/random.h>
+EXPORT_SYMBOL(random32);
+EXPORT_SYMBOL(srandom32);
+
+#include <linux/kernel.h>
+EXPORT_SYMBOL(hex_asc);
+EXPORT_SYMBOL(hex_dump_to_buffer);
+EXPORT_SYMBOL(print_hex_dump);
+EXPORT_SYMBOL(print_hex_dump_bytes);
+
+EXPORT_SYMBOL(kvasprintf);
+EXPORT_SYMBOL(kasprintf);
+
+#include <linux/string_helpers.h>
+EXPORT_SYMBOL(string_get_size);
 
+#include <linux/gcd.h>
+EXPORT_SYMBOL_GPL(gcd);

Andrew Morton

maintainer

2010-01-09 00:30 UTC #1 lore raw

Quoted 16 lines · On Tue, 5 Jan 2010 15:59:18 +0100 Andi Kleen <[email protected]> wrote:

Allow linker to eliminate unused functions in lib/*
Right now a lot of code in lib/* is obj-y and always linked in. The reason is that there is no other way to ensure the EXPORT_SYMBOLs get included.
This patch moves the EXPORT_SYMBOLs into separate files instead. This way the files actually implementing the code can be made lib-y again, and the separate export symbols pull them in for modular kernels.
For non modular kernels the linker can decide whether to use them or not.
This shrinks a allnoconfig+CONFIG_EMBEDDED=y+all options disabled kernel by about 1k on x86. Not much, but also not too shabby.

Quoted 8 lines

In some ways that's similar to the old ksyms.c files, but not as centralized.
I didn't do this for the functions in lib/* which already have Kconfig symbol. Presumably that is usually only set on demand when they are actually needed (although I'm not sure it's true for all cases).

Sneaky.

It's a bit sad to reduce the code cleanliness and maintainability in this way, but 1k is 1k.

Removing the module.h include from the .c files will hopefully help people realise that new exports shouldn't be added to the .c files.

lib/lib-syms.c line 10

Quoted 10 lines

lib/lib-syms.c +2 -1

@@ -5,9 +5,13 @@
  * On modular kernels it keeps a reference to all the lib files with
  * exports so that they can be used by modules.  On non modular
  * kernels it does nothing and the linker can decide whether a lib
- * object file is needed or not.
+ * object file is needed or not. This way unneeded library functions
+ * can be eliminated.
  */

The patch assumes a pre-existing lib-syms.c. Confused.

Andi Kleen

author

2010-01-09 16:52 UTC #2 lore raw

Quoted 4 lines

Sneaky.
It's a bit sad to reduce the code cleanliness and maintainability in this way, but 1k is 1k.

Yes. I had actually hoped for more too. I think it might bring more with -ffunction-sections/--gc-sections, but I haven't tried that.

An alternative might be also to give some more of those explicit Kconfig symbols -- then kernels with module loading enabled would benefit more too -- but I haven't investigated how many changes that would need.

But even with that it's a reasonable improvement and putting the exports separately is not too bad.

Quoted 1 line

The patch assumes a pre-existing lib-syms.c. Confused.

Sorry, some day I'll learn how to operate quilt properly.

Updated patch with all files included appended.

-Andi

---

Allow linker to eliminate unused functions in lib/*

Right now a lot of code in lib/* is obj-y and always linked in. The reason is that there is no other way to ensure the EXPORT_SYMBOLs get included.

In some ways that's similar to the old ksyms.c files, but not as centralized.

For non modular kernels the linker can decide whether to use them or not.

This shrinks a allnoconfig+CONFIG_EMBEDDED=y+all options disabled kernel by about 1k on x86. Not much, but also not too shabby.

Signed-off-by Andi Kleen <[email protected]>

---
 lib/Makefile           |    8 +++++-
 lib/bcd.c              |    3 --
 lib/bitmap-syms.c      |   32 +++++++++++++++++++++++++
 lib/bitmap.c           |   34 +++-----------------------
 lib/debug_locks.c      |    1 
 lib/div64.c            |    7 -----
 lib/gcd.c              |    3 --
 lib/halfmd4.c          |    3 --
 lib/hexdump.c          |    5 ---
 lib/kasprintf.c        |    6 ++--
 lib/lib-syms.c         |   62 +++++++++++++++++++++++++++++++++++++++++++++++++
 lib/parser.c           |    9 -------
 lib/random32.c         |    3 --
 lib/scatterlist-syms.c |   16 ++++++++++++
 lib/scatterlist.c      |   19 +++------------
 lib/sort.c             |    2 -
 lib/string_helpers.c   |    3 --
 17 files changed, 134 insertions(+), 82 deletions(-)

lib/Makefile +7 -1

Index: linux-2.6.33-rc2-ak/lib/Makefile
===================================================================
@@ -7,6 +7,10 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
 endif
 
+# Please put EXPORT_SYMBOLs into lib-syms.c or an own file (and make
+# only that obj-y), not into the files directly.
+# This way the linker can eliminate unneeded code on non modular kernels.
+
 lib-y := ctype.o string.o vsprintf.o cmdline.o \
 	 rbtree.o radix-tree.o dump_stack.o \
 	 idr.o int_sqrt.o extable.o prio_tree.o \

@@ -19,10 +23,12 @@ lib-$(CONFIG_SMP) += cpumask.o
 
 lib-y	+= kobject.o kref.o klist.o
 
-obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
+lib-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
 	 string_helpers.o gcd.o
 
+obj-y += bitmap-syms.o lib-syms.o scatterlist-syms.o
+
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
 CFLAGS_kobject_uevent.o += -DDEBUG

lib/bcd.c +0 -3

Index: linux-2.6.33-rc2-ak/lib/bcd.c
===================================================================
@@ -1,14 +1,11 @@
 #include <linux/bcd.h>
-#include <linux/module.h>
 
 unsigned bcd2bin(unsigned char val)
 {
 	return (val & 0x0f) + (val >> 4) * 10;
 }
-EXPORT_SYMBOL(bcd2bin);
 
 unsigned char bin2bcd(unsigned val)
 {
 	return ((val / 10) << 4) + val % 10;
 }
-EXPORT_SYMBOL(bin2bcd);

lib/bitmap.c +4 ~~-30~~

Index: linux-2.6.33-rc2-ak/lib/bitmap.c
===================================================================
@@ -5,7 +5,6 @@
  * This source code is licensed under the GNU General Public License,
  * Version 2.  See the file COPYING for more details.
  */
-#include <linux/module.h>
 #include <linux/ctype.h>
 #include <linux/errno.h>
 #include <linux/bitmap.h>

@@ -13,6 +12,10 @@
 #include <asm/uaccess.h>
 
 /*
+ * Please put EXPORT_SYMBOLs into bitmap-syms.c
+ */
+
+/*
  * bitmaps provide an array of bits, implemented using an an
  * array of unsigned longs.  The number of valid bits in a
  * given bitmap does _not_ need to be an exact multiple of

@@ -51,7 +54,6 @@ int __bitmap_empty(const unsigned long *
 
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_empty);
 
 int __bitmap_full(const unsigned long *bitmap, int bits)
 {

@@ -66,7 +68,6 @@ int __bitmap_full(const unsigned long *b
 
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_full);
 
 int __bitmap_equal(const unsigned long *bitmap1,
 		const unsigned long *bitmap2, int bits)

@@ -82,7 +83,6 @@ int __bitmap_equal(const unsigned long *
 
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_equal);
 
 void __bitmap_complement(unsigned long *dst, const unsigned long *src, int bits)
 {

@@ -93,7 +93,6 @@ void __bitmap_complement(unsigned long *
 	if (bits % BITS_PER_LONG)
 		dst[k] = ~src[k] & BITMAP_LAST_WORD_MASK(bits);
 }
-EXPORT_SYMBOL(__bitmap_complement);
 
 /**
  * __bitmap_shift_right - logical right shift of the bits in a bitmap

@@ -136,7 +135,6 @@ void __bitmap_shift_right(unsigned long
 	if (off)
 		memset(&dst[lim - off], 0, off*sizeof(unsigned long));
 }
-EXPORT_SYMBOL(__bitmap_shift_right);
 
 
 /**

@@ -177,7 +175,6 @@ void __bitmap_shift_left(unsigned long *
 	if (off)
 		memset(dst, 0, off*sizeof(unsigned long));
 }
-EXPORT_SYMBOL(__bitmap_shift_left);
 
 int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -190,7 +187,6 @@ int __bitmap_and(unsigned long *dst, con
 		result |= (dst[k] = bitmap1[k] & bitmap2[k]);
 	return result != 0;
 }
-EXPORT_SYMBOL(__bitmap_and);
 
 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -201,7 +197,6 @@ void __bitmap_or(unsigned long *dst, con
 	for (k = 0; k < nr; k++)
 		dst[k] = bitmap1[k] | bitmap2[k];
 }
-EXPORT_SYMBOL(__bitmap_or);
 
 void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -212,7 +207,6 @@ void __bitmap_xor(unsigned long *dst, co
 	for (k = 0; k < nr; k++)
 		dst[k] = bitmap1[k] ^ bitmap2[k];
 }
-EXPORT_SYMBOL(__bitmap_xor);
 
 int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -225,7 +219,6 @@ int __bitmap_andnot(unsigned long *dst,
 		result |= (dst[k] = bitmap1[k] & ~bitmap2[k]);
 	return result != 0;
 }
-EXPORT_SYMBOL(__bitmap_andnot);
 
 int __bitmap_intersects(const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -240,7 +233,6 @@ int __bitmap_intersects(const unsigned l
 			return 1;
 	return 0;
 }
-EXPORT_SYMBOL(__bitmap_intersects);
 
 int __bitmap_subset(const unsigned long *bitmap1,
 				const unsigned long *bitmap2, int bits)

@@ -255,7 +247,6 @@ int __bitmap_subset(const unsigned long
 			return 0;
 	return 1;
 }
-EXPORT_SYMBOL(__bitmap_subset);
 
 int __bitmap_weight(const unsigned long *bitmap, int bits)
 {

@@ -269,7 +260,6 @@ int __bitmap_weight(const unsigned long
 
 	return w;
 }
-EXPORT_SYMBOL(__bitmap_weight);
 
 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))

@@ -292,7 +282,6 @@ void bitmap_set(unsigned long *map, int
 		*p |= mask_to_set;
 	}
 }
-EXPORT_SYMBOL(bitmap_set);
 
 void bitmap_clear(unsigned long *map, int start, int nr)
 {

@@ -313,7 +302,6 @@ void bitmap_clear(unsigned long *map, in
 		*p &= ~mask_to_clear;
 	}
 }
-EXPORT_SYMBOL(bitmap_clear);
 
 /*
  * bitmap_find_next_zero_area - find a contiguous aligned zero area

@@ -350,7 +338,6 @@ again:
 	}
 	return index;
 }
-EXPORT_SYMBOL(bitmap_find_next_zero_area);
 
 /*
  * Bitmap printing & parsing functions: first version by Bill Irwin,

@@ -398,7 +385,6 @@ int bitmap_scnprintf(char *buf, unsigned
 	}
 	return len;
 }
-EXPORT_SYMBOL(bitmap_scnprintf);
 
 /**
  * __bitmap_parse - convert an ASCII hex string into a bitmap.

@@ -484,7 +470,6 @@ int __bitmap_parse(const char *buf, unsi
 
 	return 0;
 }
-EXPORT_SYMBOL(__bitmap_parse);
 
 /**
  * bitmap_parse_user()

@@ -509,7 +494,6 @@ int bitmap_parse_user(const char __user
 		return -EFAULT;
 	return __bitmap_parse((const char *)ubuf, ulen, 1, maskp, nmaskbits);
 }
-EXPORT_SYMBOL(bitmap_parse_user);
 
 /*
  * bscnl_emit(buf, buflen, rbot, rtop, bp)

@@ -569,7 +553,6 @@ int bitmap_scnlistprintf(char *buf, unsi
 	}
 	return len;
 }
-EXPORT_SYMBOL(bitmap_scnlistprintf);
 
 /**
  * bitmap_parselist - convert list format ASCII string to bitmap

@@ -616,7 +599,6 @@ int bitmap_parselist(const char *bp, uns
 	} while (*bp != '\0' && *bp != '\n');
 	return 0;
 }
-EXPORT_SYMBOL(bitmap_parselist);
 
 /**
  * bitmap_pos_to_ord(buf, pos, bits)

@@ -743,7 +725,6 @@ void bitmap_remap(unsigned long *dst, co
 			set_bit(bitmap_ord_to_pos(new, n % w, bits), dst);
 	}
 }
-EXPORT_SYMBOL(bitmap_remap);
 
 /**
  * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit

@@ -781,7 +762,6 @@ int bitmap_bitremap(int oldbit, const un
 	else
 		return bitmap_ord_to_pos(new, n % w, bits);
 }
-EXPORT_SYMBOL(bitmap_bitremap);
 
 /**
  * bitmap_onto - translate one bitmap relative to another

@@ -912,7 +892,6 @@ void bitmap_onto(unsigned long *dst, con
 		m++;
 	}
 }
-EXPORT_SYMBOL(bitmap_onto);
 
 /**
  * bitmap_fold - fold larger bitmap into smaller, modulo specified size

@@ -939,7 +918,6 @@ void bitmap_fold(unsigned long *dst, con
 	     oldbit = find_next_bit(orig, bits, oldbit + 1))
 		set_bit(oldbit % sz, dst);
 }
-EXPORT_SYMBOL(bitmap_fold);
 
 /*
  * Common code for bitmap_*_region() routines.

@@ -1043,7 +1021,6 @@ int bitmap_find_free_region(unsigned lon
 	}
 	return -ENOMEM;
 }
-EXPORT_SYMBOL(bitmap_find_free_region);
 
 /**
  * bitmap_release_region - release allocated bitmap region

@@ -1060,7 +1037,6 @@ void bitmap_release_region(unsigned long
 {
 	__reg_op(bitmap, pos, order, REG_OP_RELEASE);
 }
-EXPORT_SYMBOL(bitmap_release_region);
 
 /**
  * bitmap_allocate_region - allocate bitmap region

@@ -1080,7 +1056,6 @@ int bitmap_allocate_region(unsigned long
 	__reg_op(bitmap, pos, order, REG_OP_ALLOC);
 	return 0;
 }
-EXPORT_SYMBOL(bitmap_allocate_region);
 
 /**
  * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order.

@@ -1102,4 +1077,3 @@ void bitmap_copy_le(void *dst, const uns
 			d[i] = cpu_to_le32(src[i]);
 	}
 }
-EXPORT_SYMBOL(bitmap_copy_le);

lib/debug_locks.c +0 -1

Index: linux-2.6.33-rc2-ak/lib/debug_locks.c
===================================================================
@@ -11,7 +11,6 @@
 #include <linux/kernel.h>
 #include <linux/rwsem.h>
 #include <linux/mutex.h>
-#include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/debug_locks.h>

lib/div64.c +1 -6

Index: linux-2.6.33-rc2-ak/lib/div64.c
===================================================================
@@ -16,7 +16,6 @@
  * assembly versions such as arch/ppc/lib/div64.S and arch/sh/lib/div64.S.
  */
 
-#include <linux/module.h>
 #include <linux/math64.h>
 
 /* Not needed on 64bit architectures */

@@ -55,8 +54,6 @@ uint32_t __attribute__((weak)) __div64_3
 	return rem;
 }
 
-EXPORT_SYMBOL(__div64_32);
-
 #ifndef div_s64_rem
 s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
 {

@@ -74,7 +71,6 @@ s64 div_s64_rem(s64 dividend, s32 diviso
 	}
 	return quotient;
 }
-EXPORT_SYMBOL(div_s64_rem);
 #endif
 
 /* 64bit divisor, dividend and result. dynamic precision */

@@ -94,7 +90,6 @@ u64 div64_u64(u64 dividend, u64 divisor)
 
 	return div_u64(dividend, d);
 }
-EXPORT_SYMBOL(div64_u64);
 #endif
 
 #endif /* BITS_PER_LONG == 32 */

@@ -107,4 +102,4 @@ u32 iter_div_u64_rem(u64 dividend, u32 d
 {
 	return __iter_div_u64_rem(dividend, divisor, remainder);
 }
-EXPORT_SYMBOL(iter_div_u64_rem);
+

lib/gcd.c +1 -2

Index: linux-2.6.33-rc2-ak/lib/gcd.c
===================================================================
@@ -1,6 +1,5 @@
 #include <linux/kernel.h>
 #include <linux/gcd.h>
-#include <linux/module.h>
 
 /* Greatest common divisor */
 unsigned long gcd(unsigned long a, unsigned long b)

@@ -15,4 +14,4 @@ unsigned long gcd(unsigned long a, unsig
 	}
 	return b;
 }
-EXPORT_SYMBOL_GPL(gcd);
+

lib/halfmd4.c +1 -2

Index: linux-2.6.33-rc2-ak/lib/halfmd4.c
===================================================================
@@ -1,5 +1,4 @@
 #include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/cryptohash.h>
 
 /* F, G and H are basic MD4 functions: selection, majority, parity */

@@ -63,4 +62,4 @@ __u32 half_md4_transform(__u32 buf[4], _
 
 	return buf[1]; /* "most hashed" word */
 }
-EXPORT_SYMBOL(half_md4_transform);
+

lib/hexdump.c +0 -5

Index: linux-2.6.33-rc2-ak/lib/hexdump.c
===================================================================
@@ -10,10 +10,8 @@
 #include <linux/types.h>
 #include <linux/ctype.h>
 #include <linux/kernel.h>
-#include <linux/module.h>
 
 const char hex_asc[] = "0123456789abcdef";
-EXPORT_SYMBOL(hex_asc);
 
 /**
  * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory

@@ -117,7 +115,6 @@ void hex_dump_to_buffer(const void *buf,
 nil:
 	linebuf[lx++] = '\0';
 }
-EXPORT_SYMBOL(hex_dump_to_buffer);
 
 /**
  * print_hex_dump - print a text hex dump to syslog for a binary blob of data

@@ -181,7 +178,6 @@ void print_hex_dump(const char *level, c
 		}
 	}
 }
-EXPORT_SYMBOL(print_hex_dump);
 
 /**
  * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params

@@ -201,4 +197,3 @@ void print_hex_dump_bytes(const char *pr
 	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1,
 			buf, len, 1);
 }
-EXPORT_SYMBOL(print_hex_dump_bytes);

lib/kasprintf.c +3 -3

Index: linux-2.6.33-rc2-ak/lib/kasprintf.c
===================================================================
@@ -5,9 +5,10 @@
  */
 
 #include <stdarg.h>
-#include <linux/module.h>
 #include <linux/types.h>
 #include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
 
 /* Simplified asprintf. */
 char *kvasprintf(gfp_t gfp, const char *fmt, va_list ap)

@@ -28,7 +29,6 @@ char *kvasprintf(gfp_t gfp, const char *
 
 	return p;
 }
-EXPORT_SYMBOL(kvasprintf);
 
 char *kasprintf(gfp_t gfp, const char *fmt, ...)
 {

@@ -41,4 +41,4 @@ char *kasprintf(gfp_t gfp, const char *f
 
 	return p;
 }
-EXPORT_SYMBOL(kasprintf);
+

lib/parser.c +1 -8

Index: linux-2.6.33-rc2-ak/lib/parser.c
===================================================================
@@ -5,8 +5,8 @@
  * Version 2.  See the file COPYING for more details.
  */
 
+#include <linux/types.h>
 #include <linux/ctype.h>
-#include <linux/module.h>
 #include <linux/parser.h>
 #include <linux/slab.h>
 #include <linux/string.h>

@@ -222,10 +222,3 @@ char *match_strdup(const substring_t *s)
 		match_strlcpy(p, s, sz);
 	return p;
 }
-
-EXPORT_SYMBOL(match_token);
-EXPORT_SYMBOL(match_int);
-EXPORT_SYMBOL(match_octal);
-EXPORT_SYMBOL(match_hex);
-EXPORT_SYMBOL(match_strlcpy);
-EXPORT_SYMBOL(match_strdup);

lib/random32.c +0 -3

Index: linux-2.6.33-rc2-ak/lib/random32.c
===================================================================
@@ -35,7 +35,6 @@
 
 #include <linux/types.h>
 #include <linux/percpu.h>
-#include <linux/module.h>
 #include <linux/jiffies.h>
 #include <linux/random.h>

@@ -79,7 +78,6 @@ u32 random32(void)
 	put_cpu_var(state);
 	return r;
 }
-EXPORT_SYMBOL(random32);
 
 /**
  *	srandom32 - add entropy to pseudo random number generator

@@ -99,7 +97,6 @@ void srandom32(u32 entropy)
 		state->s1 = __seed(state->s1 ^ entropy, 1);
 	}
 }
-EXPORT_SYMBOL(srandom32);
 
 /*
  *	Generate some initially weak seeding values to allow

lib/scatterlist.c +5 ~~-14~~

Index: linux-2.6.33-rc2-ak/lib/scatterlist.c
===================================================================
@@ -6,10 +6,13 @@
  * This source code is licensed under the GNU General Public License,
  * Version 2. See the file COPYING for more details.
  */
-#include <linux/module.h>
 #include <linux/scatterlist.h>
 #include <linux/highmem.h>
 
+/*
+ * Please put EXPORT_SYMBOLs into scatterlist-syms.c
+ */
+
 /**
  * sg_next - return the next scatterlist entry in a list
  * @sg:		The current sg entry

@@ -34,7 +37,6 @@ struct scatterlist *sg_next(struct scatt
 
 	return sg;
 }
-EXPORT_SYMBOL(sg_next);
 
 /**
  * sg_last - return the last scatterlist entry in a list

@@ -68,7 +70,6 @@ struct scatterlist *sg_last(struct scatt
 #endif
 	return ret;
 }
-EXPORT_SYMBOL(sg_last);
 
 /**
  * sg_init_table - Initialize SG table

@@ -92,7 +93,6 @@ void sg_init_table(struct scatterlist *s
 #endif
 	sg_mark_end(&sgl[nents - 1]);
 }
-EXPORT_SYMBOL(sg_init_table);
 
 /**
  * sg_init_one - Initialize a single entry sg list

@@ -106,7 +106,6 @@ void sg_init_one(struct scatterlist *sg,
 	sg_init_table(sg, 1);
 	sg_set_buf(sg, buf, buflen);
 }
-EXPORT_SYMBOL(sg_init_one);
 
 /*
  * The default behaviour of sg_alloc_table() is to use these kmalloc/kfree

@@ -175,7 +174,6 @@ void __sg_free_table(struct sg_table *ta
 
 	table->sgl = NULL;
 }
-EXPORT_SYMBOL(__sg_free_table);
 
 /**
  * sg_free_table - Free a previously allocated sg table

@@ -186,7 +184,6 @@ void sg_free_table(struct sg_table *tabl
 {
 	__sg_free_table(table, SG_MAX_SINGLE_ALLOC, sg_kfree);
 }
-EXPORT_SYMBOL(sg_free_table);
 
 /**
  * __sg_alloc_table - Allocate and initialize an sg table with given allocator

@@ -268,7 +265,6 @@ int __sg_alloc_table(struct sg_table *ta
 
 	return 0;
 }
-EXPORT_SYMBOL(__sg_alloc_table);
 
 /**
  * sg_alloc_table - Allocate and initialize an sg table

@@ -292,7 +288,6 @@ int sg_alloc_table(struct sg_table *tabl
 
 	return ret;
 }
-EXPORT_SYMBOL(sg_alloc_table);
 
 /**
  * sg_miter_start - start mapping iteration over a sg list

@@ -317,7 +312,6 @@ void sg_miter_start(struct sg_mapping_it
 	WARN_ON(!(flags & (SG_MITER_TO_SG | SG_MITER_FROM_SG)));
 	miter->__flags = flags;
 }
-EXPORT_SYMBOL(sg_miter_start);
 
 /**
  * sg_miter_next - proceed mapping iterator to the next mapping

@@ -372,7 +366,6 @@ bool sg_miter_next(struct sg_mapping_ite
 
 	return true;
 }
-EXPORT_SYMBOL(sg_miter_next);
 
 /**
  * sg_miter_stop - stop mapping iteration

@@ -410,7 +403,6 @@ void sg_miter_stop(struct sg_mapping_ite
 		miter->consumed = 0;
 	}
 }
-EXPORT_SYMBOL(sg_miter_stop);
 
 /**
  * sg_copy_buffer - Copy data between a linear buffer and an SG list

@@ -475,7 +467,6 @@ size_t sg_copy_from_buffer(struct scatte
 {
 	return sg_copy_buffer(sgl, nents, buf, buflen, 0);
 }
-EXPORT_SYMBOL(sg_copy_from_buffer);
 
 /**
  * sg_copy_to_buffer - Copy from an SG list to a linear buffer

@@ -492,4 +483,4 @@ size_t sg_copy_to_buffer(struct scatterl
 {
 	return sg_copy_buffer(sgl, nents, buf, buflen, 1);
 }
-EXPORT_SYMBOL(sg_copy_to_buffer);
+

lib/sort.c +0 -2

Index: linux-2.6.33-rc2-ak/lib/sort.c
===================================================================
@@ -87,8 +87,6 @@ void sort(void *base, size_t num, size_t
 	}
 }
 
-EXPORT_SYMBOL(sort);
-
 #if 0
 /* a simple boot-time regression test */

lib/string_helpers.c +1 -2

Index: linux-2.6.33-rc2-ak/lib/string_helpers.c
===================================================================
@@ -5,7 +5,6 @@
  */
 #include <linux/kernel.h>
 #include <linux/math64.h>
-#include <linux/module.h>
 #include <linux/string_helpers.h>
 
 /**

@@ -65,4 +64,4 @@ int string_get_size(u64 size, const enum
 
 	return 0;
 }
-EXPORT_SYMBOL(string_get_size);
+

lib/lib-syms.c new file +62 -0

62 lines not on this page · raw message

lib/bitmap-syms.c new file +32 -0

Index: linux-2.6.33-rc2-ak/lib/bitmap-syms.c
===================================================================
@@ -0,0 +1,32 @@
+#include <linux/module.h>
+#include <linux/bitmap.h>
+
+EXPORT_SYMBOL(__bitmap_empty);
+EXPORT_SYMBOL(__bitmap_full);
+EXPORT_SYMBOL(__bitmap_equal);
+EXPORT_SYMBOL(__bitmap_complement);
+EXPORT_SYMBOL(__bitmap_shift_right);
+EXPORT_SYMBOL(__bitmap_shift_left);
+EXPORT_SYMBOL(__bitmap_and);
+EXPORT_SYMBOL(__bitmap_or);
+EXPORT_SYMBOL(__bitmap_xor);
+EXPORT_SYMBOL(__bitmap_andnot);
+EXPORT_SYMBOL(__bitmap_intersects);
+EXPORT_SYMBOL(__bitmap_subset);
+EXPORT_SYMBOL(__bitmap_weight);
+EXPORT_SYMBOL(bitmap_set);
+EXPORT_SYMBOL(bitmap_clear);
+EXPORT_SYMBOL(bitmap_find_next_zero_area);
+EXPORT_SYMBOL(bitmap_scnprintf);
+EXPORT_SYMBOL(__bitmap_parse);
+EXPORT_SYMBOL(bitmap_parse_user);
+EXPORT_SYMBOL(bitmap_scnlistprintf);
+EXPORT_SYMBOL(bitmap_parselist);
+EXPORT_SYMBOL(bitmap_remap);
+EXPORT_SYMBOL(bitmap_bitremap);
+EXPORT_SYMBOL(bitmap_onto);
+EXPORT_SYMBOL(bitmap_fold);
+EXPORT_SYMBOL(bitmap_find_free_region);
+EXPORT_SYMBOL(bitmap_release_region);
+EXPORT_SYMBOL(bitmap_allocate_region);
+EXPORT_SYMBOL(bitmap_copy_le);

lib/scatterlist-syms.c new file +16 -0

Index: linux-2.6.33-rc2-ak/lib/scatterlist-syms.c
===================================================================
@@ -0,0 +1,16 @@
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+
+EXPORT_SYMBOL(sg_next);
+EXPORT_SYMBOL(sg_last);
+EXPORT_SYMBOL(sg_init_table);
+EXPORT_SYMBOL(sg_init_one);
+EXPORT_SYMBOL(__sg_free_table);
+EXPORT_SYMBOL(sg_free_table);
+EXPORT_SYMBOL(__sg_alloc_table);
+EXPORT_SYMBOL(sg_alloc_table);
+EXPORT_SYMBOL(sg_miter_start);
+EXPORT_SYMBOL(sg_miter_next);
+EXPORT_SYMBOL(sg_miter_stop);
+EXPORT_SYMBOL(sg_copy_from_buffer);
+EXPORT_SYMBOL(sg_copy_to_buffer);

Signature · 1 line

[email protected] -- Speaking for myself only.

Dave Chinner

2010-01-10 23:17 UTC #3 lore raw

Quoted 12 lines · Andi Kleen

Quoted 4 lines
Sneaky.
It's a bit sad to reduce the code cleanliness and maintainability in this way, but 1k is 1k.
Yes. I had actually hoped for more too. I think it might bring more with -ffunction-sections/--gc-sections, but I haven't tried that.
An alternative might be also to give some more of those explicit Kconfig symbols -- then kernels with module loading enabled would benefit more too -- but I haven't investigated how many changes that would need.

Quoted 8 lines

But even with that it's a reasonable improvement and putting the exports separately is not too bad.
Quoted 1 line
The patch assumes a pre-existing lib-syms.c. Confused.
Sorry, some day I'll learn how to operate quilt properly.
Updated patch with all files included appended.

Andi, how do you want to handle the overlap between this and the list_sort() patch I sent? I'm going to need a list_sort() available in the XFS tree well before the 2.6.34 merge window....

Cheers,

Dave.

Signature · 2 lines

Dave Chinner
[email protected]

Christoph Hellwig

2010-01-11 10:52 UTC #4 lore raw

Quoted 3 lines · Dave Chinner

Andi, how do you want to handle the overlap between this and the list_sort() patch I sent? I'm going to need a list_sort() available in the XFS tree well before the 2.6.34 merge window....

Honestly, if Andrew and Linus play with the game I'd just throw in your patch to move the two indentical list_sort implementations into lib/ right now. It's just moving stuff around so the normal merge window shouldn't apply. This would make life a lot easier for introducing new users in .34.

Andi Kleen

author

2010-01-11 14:24 UTC #5 lore raw

In reply to Dave Chinner

Quoted 18 lines · Dave Chinner

Quoted 17 lines · Andi Kleen
Quoted 4 lines
Sneaky.
It's a bit sad to reduce the code cleanliness and maintainability in this way, but 1k is 1k.
Yes. I had actually hoped for more too. I think it might bring more with -ffunction-sections/--gc-sections, but I haven't tried that.
An alternative might be also to give some more of those explicit Kconfig symbols -- then kernels with module loading enabled would benefit more too -- but I haven't investigated how many changes that would need.
But even with that it's a reasonable improvement and putting the exports separately is not too bad.
Quoted 1 line
The patch assumes a pre-existing lib-syms.c. Confused.

Quoted 7 lines

Quoted 3 lines
Sorry, some day I'll learn how to operate quilt properly.
Updated patch with all files included appended.
Andi, how do you want to handle the overlap between this and the list_sort() patch I sent? I'm going to need a list_sort() available in the XFS tree well before the 2.6.34 merge window....

Shouldn't be difficult to merge, it's just a few lines. Someone will do that.

It wou;ld be better if you put it into a separate file like I suggested earlier though, then the list_sort() could be actually eliminated when not needed.

-Andi

Dave Chinner

2010-01-11 22:49 UTC #6 lore raw

Quoted 27 lines · Andi Kleen

Quoted 18 lines · Dave Chinner
Quoted 17 lines · Andi Kleen
Quoted 4 lines
Sneaky.
It's a bit sad to reduce the code cleanliness and maintainability in this way, but 1k is 1k.
Yes. I had actually hoped for more too. I think it might bring more with -ffunction-sections/--gc-sections, but I haven't tried that.
An alternative might be also to give some more of those explicit Kconfig symbols -- then kernels with module loading enabled would benefit more too -- but I haven't investigated how many changes that would need.
But even with that it's a reasonable improvement and putting the exports separately is not too bad.
Quoted 1 line
The patch assumes a pre-existing lib-syms.c. Confused.
Quoted 7 lines
Quoted 3 lines
Sorry, some day I'll learn how to operate quilt properly.
Updated patch with all files included appended.
Andi, how do you want to handle the overlap between this and the list_sort() patch I sent? I'm going to need a list_sort() available in the XFS tree well before the 2.6.34 merge window....

Quoted 6 lines

Shouldn't be difficult to merge, it's just a few lines. Someone will do that.
It wou;ld be better if you put it into a separate file like I suggested earlier though, then the list_sort() could be actually eliminated when not needed.

OK, I'll respin it to do that, then push it onwards.

Cheers,

Dave.

Signature · 2 lines

Dave Chinner
[email protected]

Andrew Morton

maintainer

2010-01-15 23:44 UTC #7 lore raw

In reply to Andi Kleen

Quoted 1 line · On Sat, 9 Jan 2010 17:51:56 +0100 Andi Kleen <[email protected]> wrote:

Allow linker to eliminate unused functions in lib/*

i386 allmodconfig:

lib/lib-syms.c:21: error: '__div64_32' undeclared here (not in a function) lib/lib-syms.c:21: warning: type defaults to 'int' in declaration of '__div64_32'

I'll drop

lib-allow-linker-to-eliminate-unused-functions.patch lib-allow-linker-to-eliminate-unused-functions-fix.patch lib-allow-linker-to-eliminate-unused-functions-fix-2.patch

for now and will return the patch for warranty repairs, please.

lib-allow-linker-to-eliminate-unused-functions-fix.patch is a linux-next thing, so if you base the next version on mainline, please remind me to resurrect lib-allow-linker-to-eliminate-unused-functions-fix.patch.

I have travel coming up and won't be very functional until late next week.

Andi Kleen

author

2010-01-16 11:07 UTC #8 lore raw

Quoted 7 lines

I'll drop
lib-allow-linker-to-eliminate-unused-functions.patch lib-allow-linker-to-eliminate-unused-functions-fix.patch lib-allow-linker-to-eliminate-unused-functions-fix-2.patch
for now and will return the patch for warranty repairs, please.

Ok. I'll double check allno and allmod and send a new patch.

Sorry for the trouble

-Andi

Signature · 1 line

[email protected] -- Speaking for myself only.