Re: + inflate-refactor-inflate-malloc-code.patch added to -mm tree

From: Thomas Petazzoni
Date: Mon Feb 18 2008 - 08:07:51 EST


Hi Russell,

Le Fri, 15 Feb 2008 20:31:03 +0000,
Russell King <rmk@xxxxxxxxxxxxxxxx> a Ãcrit :

> Note these additional calls in the above function, which aren't
> replaced in some way in the "cleaned up" code...
>
> They're there so that machines which have a watchdog started well
> before the machine gets anywhere near the kernel can continue to have
> the watchdog patted during the decompress, thereby avoiding the
> watchdog resetting the machine before we even reach the kernel.
>
> That said, none of the current ARM platforms seem to use them
> anymore, so if the only references to these functions are being
> removed, please remove the definitions from
> include/asm-arm/arch-*/uncompress.h as well, rather than leaving them
> dangling.

Thanks for the review. I missed the arch_decomp_wdog() part. The
updated patch below should fix it (the generic inflate code regularly
calls arch_decomp_wdog() if ARCH_HAS_DECOMP_WDOG is defined). The
arch_decomp_wdog() call is still used by the S3C platform (see
include/asm-arm/plat-s3c/uncompress.h).

The updated patch also fixes the build problem reported by Byron
Bradley on ARM. On ARM, I renamed free_mem_ptr_end to free_mem_end_ptr
in order to match the other architectures. I also defined
free_mem_end_ptr on architectures in which it wasn't defined (CRIS v10
and CRIS v32).

I compiled/booted the modified kernel on x86 and ARM.

I hope that the patch is better now.

Thanks for your comments and review,

Thomas

---

inflate: refactor inflate malloc code

Inflate requires some dynamic memory allocation very early in the boot
process and this is provided with a set of four functions:
malloc/free/gzip_mark/gzip_release.

The old inflate code used a mark/release strategy rather than
implement free. This new version instead keeps a count on the number
of outstanding allocations and when it hits zero, it resets the malloc
arena.

This allows removing all the mark and release implementations and
unifying all the malloc/free implementations.

The architecture-dependent code must define two addresses:
- free_mem_ptr, the address of the beginning of the area in which
allocations should be made
- free_mem_end_ptr, the address of the end of the area in which
allocations should be made. If set to 0, then no check is made on
the number of allocations, it just grows as much as needed

The architecture-dependent code can also provide an arch_decomp_wdog()
function call. This function will be called several times during the
decompression process, and allow to notify the watchdog that the
system is still running. If an architecture provides such a call, then
it must define ARCH_HAS_DECOMP_WDOG so that the generic inflate code
calls arch_decomp_wdog().

Work initially done by Matt Mackall <mpm@xxxxxxxxxxx>, updated to a
recent version of the kernel by me.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>

---
arch/alpha/boot/misc.c | 39 +------------------
arch/arm/boot/compressed/misc.c | 59 +++---------------------------
arch/cris/arch-v10/boot/compressed/misc.c | 35 -----------------
arch/cris/arch-v32/boot/compressed/misc.c | 35 -----------------
arch/h8300/boot/compressed/misc.c | 38 -------------------
arch/m32r/boot/compressed/misc.c | 37 ------------------
arch/mn10300/boot/compressed/misc.c | 37 ------------------
arch/sh/boot/compressed/misc_32.c | 38 -------------------
arch/sh/boot/compressed/misc_64.c | 40 --------------------
arch/x86/boot/compressed/misc.c | 37 ------------------
init/do_mounts_rd.c | 25 +-----------
init/initramfs.c | 22 +----------
lib/inflate.c | 52 ++++++++++++++++++++++----
13 files changed, 60 insertions(+), 434 deletions(-)

Index: linux/arch/alpha/boot/misc.c
===================================================================
--- linux.orig/arch/alpha/boot/misc.c
+++ linux/arch/alpha/boot/misc.c
@@ -78,8 +78,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

static char *input_data;
static int input_data_size;
@@ -88,51 +86,18 @@
static ulg output_ptr;
static ulg bytes_out;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
static void gzip_mark(void **);
static void gzip_release(void **);

extern int end;
static ulg free_mem_ptr;
-static ulg free_mem_ptr_end;
+static ulg free_mem_end_ptr;

#define HEAP_SIZE 0x3000

#include "../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
- if (free_mem_ptr <= 0) error("Memory error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_ptr_end)
- error("Out of memory");
- return p;
-}
-
-static void free(void *where)
-{ /* gzip_mark & gzip_release do the free */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
/* ===========================================================================
* Fill the input buffer. This is called only when the buffer is empty
* and at least one byte is really needed.
@@ -193,7 +158,7 @@

/* FIXME FIXME FIXME */
free_mem_ptr = (ulg)output_start + ksize;
- free_mem_ptr_end = (ulg)output_start + ksize + 0x200000;
+ free_mem_end_ptr = (ulg)output_start + ksize + 0x200000;
/* FIXME FIXME FIXME */

/* put in temp area to reduce initial footprint */
Index: linux/arch/arm/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/arm/boot/compressed/misc.c
+++ linux/arch/arm/boot/compressed/misc.c
@@ -217,8 +217,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

extern char input_data[];
extern char input_data_end[];
@@ -227,64 +225,21 @@
static ulg output_ptr;
static ulg bytes_out;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

static void putstr(const char *);

extern int end;
static ulg free_mem_ptr;
-static ulg free_mem_ptr_end;
+static ulg free_mem_end_ptr;

-#define HEAP_SIZE 0x3000
-
-#include "../../../../lib/inflate.c"
-
-#ifndef STANDALONE_DEBUG
-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
- if (free_mem_ptr <= 0) error("Memory error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_ptr_end)
- error("Out of memory");
- return p;
-}
-
-static void free(void *where)
-{ /* gzip_mark & gzip_release do the free */
-}
-
-static void gzip_mark(void **ptr)
-{
- arch_decomp_wdog();
- *ptr = (void *) free_mem_ptr;
-}
+#ifdef STANDALONE_DEBUG
+#define NO_INFLATE_MALLOC
+#endif

-static void gzip_release(void **ptr)
-{
- arch_decomp_wdog();
- free_mem_ptr = (long) *ptr;
-}
-#else
-static void gzip_mark(void **ptr)
-{
-}
+#define ARCH_HAS_DECOMP_WDOG

-static void gzip_release(void **ptr)
-{
-}
-#endif
+#include "../../../../lib/inflate.c"

/* ===========================================================================
* Fill the input buffer. This is called only when the buffer is empty
@@ -348,7 +303,7 @@
{
output_data = (uch *)output_start; /* Points to kernel start */
free_mem_ptr = free_mem_ptr_p;
- free_mem_ptr_end = free_mem_ptr_end_p;
+ free_mem_end_ptr = free_mem_ptr_end_p;
__machine_arch_type = arch_id;

arch_decomp_setup();
Index: linux/arch/cris/arch-v10/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/cris/arch-v10/boot/compressed/misc.c
+++ linux/arch/cris/arch-v10/boot/compressed/misc.c
@@ -84,8 +84,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

extern char *input_data; /* lives in head.S */

@@ -93,11 +91,7 @@
static uch *output_data;
static unsigned long output_ptr = 0;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

static void puts(const char *);

@@ -105,37 +99,10 @@

extern int end;
static long free_mem_ptr = (long)&end;
+static long free_mem_end_ptr = 0;

#include "../../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
/* decompressor info and error messages to serial console */

static void
Index: linux/arch/cris/arch-v32/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/cris/arch-v32/boot/compressed/misc.c
+++ linux/arch/cris/arch-v32/boot/compressed/misc.c
@@ -89,8 +89,6 @@

static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

extern char *input_data; /* lives in head.S */

@@ -98,11 +96,7 @@
static uch *output_data;
static unsigned long output_ptr = 0;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

static void puts(const char *);

@@ -110,37 +104,10 @@

extern int _end;
static long free_mem_ptr = (long)&_end;
+static long free_mem_end_ptr = 0;

#include "../../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
/* decompressor info and error messages to serial console */

static inline void
Index: linux/arch/h8300/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/h8300/boot/compressed/misc.c
+++ linux/arch/h8300/boot/compressed/misc.c
@@ -67,8 +67,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

extern char input_data[];
extern int input_len;
@@ -77,11 +75,7 @@
static uch *output_data;
static unsigned long output_ptr = 0;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

int puts(const char *);

@@ -98,38 +92,6 @@
#define TDR *((volatile unsigned char *)0xffff8b)
#define SSR *((volatile unsigned char *)0xffff8c)

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
- if (free_mem_ptr == 0) error("Memory error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_end_ptr)
- error("Out of memory");
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
int puts(const char *s)
{
return 0;
Index: linux/arch/m32r/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/m32r/boot/compressed/misc.c
+++ linux/arch/m32r/boot/compressed/misc.c
@@ -70,8 +70,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

static unsigned char *input_data;
static int input_len;
@@ -82,9 +80,6 @@

#include "m32r_sio.c"

-static void *malloc(int size);
-static void free(void *where);
-
static unsigned long free_mem_ptr;
static unsigned long free_mem_end_ptr;

@@ -92,38 +87,6 @@

#include "../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
- if (free_mem_ptr == 0) error("Memory error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_end_ptr)
- error("Out of memory");
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
void* memset(void* s, int c, size_t n)
{
int i;
Index: linux/arch/mn10300/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/mn10300/boot/compressed/misc.c
+++ linux/arch/mn10300/boot/compressed/misc.c
@@ -153,26 +153,9 @@
static unsigned long output_ptr;


-static void *malloc(int size);
-
-static inline void free(void *where)
-{ /* Don't care */
-}
-
static unsigned long free_mem_ptr = (unsigned long) &end;
static unsigned long free_mem_end_ptr = (unsigned long) &end + 0x90000;

-static inline void gzip_mark(void **ptr)
-{
- kputs(".");
- *ptr = (void *) free_mem_ptr;
-}
-
-static inline void gzip_release(void **ptr)
-{
- free_mem_ptr = (unsigned long) *ptr;
-}
-
#define INPLACE_MOVE_ROUTINE 0x1000
#define LOW_BUFFER_START 0x2000
#define LOW_BUFFER_END 0x90000
@@ -186,26 +169,6 @@

#include "../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size < 0)
- error("Malloc error\n");
- if (!free_mem_ptr)
- error("Memory error\n");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *) free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_end_ptr)
- error("\nOut of memory\n");
-
- return p;
-}
-
static inline void scroll(void)
{
int i;
Index: linux/arch/sh/boot/compressed/misc_32.c
===================================================================
--- linux.orig/arch/sh/boot/compressed/misc_32.c
+++ linux/arch/sh/boot/compressed/misc_32.c
@@ -74,8 +74,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

extern char input_data[];
extern int input_len;
@@ -84,11 +82,7 @@
static uch *output_data;
static unsigned long output_ptr = 0;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

int puts(const char *);

@@ -101,38 +95,6 @@

#include "../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
- if (free_mem_ptr == 0) error("Memory error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_end_ptr)
- error("Out of memory");
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
#ifdef CONFIG_SH_STANDARD_BIOS
size_t strlen(const char *s)
{
Index: linux/arch/sh/boot/compressed/misc_64.c
===================================================================
--- linux.orig/arch/sh/boot/compressed/misc_64.c
+++ linux/arch/sh/boot/compressed/misc_64.c
@@ -72,8 +72,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

extern char input_data[];
extern int input_len;
@@ -82,11 +80,7 @@
static uch *output_data;
static unsigned long output_ptr = 0;

-static void *malloc(int size);
-static void free(void *where);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

static void puts(const char *);

@@ -99,40 +93,6 @@

#include "../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size < 0)
- error("Malloc error\n");
- if (free_mem_ptr == 0)
- error("Memory error\n");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *) free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_end_ptr)
- error("\nOut of memory\n");
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (long) *ptr;
-}
-
void puts(const char *s)
{
}
Index: linux/arch/x86/boot/compressed/misc.c
===================================================================
--- linux.orig/arch/x86/boot/compressed/misc.c
+++ linux/arch/x86/boot/compressed/misc.c
@@ -168,8 +168,6 @@
static int fill_inbuf(void);
static void flush_window(void);
static void error(char *m);
-static void gzip_mark(void **);
-static void gzip_release(void **);

/*
* This is set up by the setup-routine at boot-time
@@ -187,9 +185,6 @@

static long bytes_out = 0;

-static void *malloc(int size);
-static void free(void *where);
-
static void *memset(void *s, int c, unsigned n);
static void *memcpy(void *dest, const void *src, unsigned n);

@@ -220,38 +215,6 @@

#include "../../../../lib/inflate.c"

-static void *malloc(int size)
-{
- void *p;
-
- if (size <0) error("Malloc error");
- if (free_mem_ptr <= 0) error("Memory error");
-
- free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
-
- p = (void *)free_mem_ptr;
- free_mem_ptr += size;
-
- if (free_mem_ptr >= free_mem_end_ptr)
- error("Out of memory");
-
- return p;
-}
-
-static void free(void *where)
-{ /* Don't care */
-}
-
-static void gzip_mark(void **ptr)
-{
- *ptr = (void *) free_mem_ptr;
-}
-
-static void gzip_release(void **ptr)
-{
- free_mem_ptr = (memptr) *ptr;
-}
-
static void scroll(void)
{
int i;
Index: linux/init/do_mounts_rd.c
===================================================================
--- linux.orig/init/do_mounts_rd.c
+++ linux/init/do_mounts_rd.c
@@ -313,32 +313,11 @@

static int __init fill_inbuf(void);
static void __init flush_window(void);
-static void __init *malloc(size_t size);
-static void __init free(void *where);
static void __init error(char *m);
-static void __init gzip_mark(void **);
-static void __init gzip_release(void **);

-#include "../lib/inflate.c"
-
-static void __init *malloc(size_t size)
-{
- return kmalloc(size, GFP_KERNEL);
-}
-
-static void __init free(void *where)
-{
- kfree(where);
-}
-
-static void __init gzip_mark(void **ptr)
-{
-}
-
-static void __init gzip_release(void **ptr)
-{
-}
+#define NO_INFLATE_MALLOC

+#include "../lib/inflate.c"

/* ===========================================================================
* Fill the input buffer. This is called only when the buffer is empty
Index: linux/init/initramfs.c
===================================================================
--- linux.orig/init/initramfs.c
+++ linux/init/initramfs.c
@@ -14,16 +14,6 @@
message = x;
}

-static void __init *malloc(size_t size)
-{
- return kmalloc(size, GFP_KERNEL);
-}
-
-static void __init free(void *where)
-{
- kfree(where);
-}
-
/* link hash */

#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
@@ -407,18 +397,10 @@

static void __init flush_window(void);
static void __init error(char *m);
-static void __init gzip_mark(void **);
-static void __init gzip_release(void **);

-#include "../lib/inflate.c"
+#define NO_INFLATE_MALLOC

-static void __init gzip_mark(void **ptr)
-{
-}
-
-static void __init gzip_release(void **ptr)
-{
-}
+#include "../lib/inflate.c"

/* ===========================================================================
* Write the output window window[0..outcnt-1] and update crc and bytes_out.
Index: linux/lib/inflate.c
===================================================================
--- linux.orig/lib/inflate.c
+++ linux/lib/inflate.c
@@ -230,6 +230,45 @@
#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
#define DUMPBITS(n) {b>>=(n);k-=(n);}

+#ifndef NO_INFLATE_MALLOC
+/* A trivial malloc implementation, adapted from
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ */
+
+static unsigned long malloc_ptr;
+static int malloc_count;
+
+static void *malloc(int size)
+{
+ void *p;
+
+ if (size <0)
+ error("Malloc error");
+ if (!malloc_ptr)
+ malloc_ptr = free_mem_ptr;
+
+ malloc_ptr = (malloc_ptr + 3) & ~3; /* Align */
+
+ p = (void *)malloc_ptr;
+ malloc_ptr += size;
+
+ if (free_mem_end_ptr && malloc_ptr >= free_mem_end_ptr)
+ error("Out of memory");
+
+ malloc_count++;
+ return p;
+}
+
+static void free(void *where)
+{
+ malloc_count--;
+ if (!malloc_count)
+ malloc_ptr = free_mem_ptr;
+}
+#else
+#define malloc(a) kmalloc(a, GFP_KERNEL)
+#define free(a) kfree(a)
+#endif

/*
Huffman code decoding is performed using a multi-level table lookup.
@@ -1042,7 +1081,6 @@
int e; /* last block flag */
int r; /* result code */
unsigned h; /* maximum struct huft's malloc'ed */
- void *ptr;

/* initialize window, bit buffer */
wp = 0;
@@ -1054,12 +1092,12 @@
h = 0;
do {
hufts = 0;
- gzip_mark(&ptr);
- if ((r = inflate_block(&e)) != 0) {
- gzip_release(&ptr);
- return r;
- }
- gzip_release(&ptr);
+#ifdef ARCH_HAS_DECOMP_WDOG
+ arch_decomp_wdog();
+#endif
+ r = inflate_block(&e);
+ if (r)
+ return r;
if (hufts > h)
h = hufts;
} while (!e);


--
Thomas Petazzoni, Free Electrons
Free Embedded Linux Training Materials
on http://free-electrons.com/training
(More than 1500 pages!)

Attachment: signature.asc
Description: PGP signature