Linuxメモ（跡地）

ARMv7 ARCHのARMから...

• ストロングリオーダ（Strongly ordered）
• ノーマル()\メモリ属性は以下がある。
  • (Outer Shareable)
  • (Inner Shareable)
  • (Non shareable)
• デバイス
  • (shareable)
  • (Non shareable)

mm初期化処理を追う... ために, kernel起動先頭から少し追ってみる.

FILE:arch/arm/kernel/vmlinux.lds
 .init.pv_table : {
  __pv_table_begin = .;
  *(.pv_table)
  __pv_table_end = .;
 }

 Kernel startup entry point.
 ---------------------------

 This is normally called from the decompressor code.  The requirements
 are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
 r1 = machine nr, r2 = atags or dtb pointer.

 This code is mostly position independent, so if you link the kernel at
 0xc0008000, you call this at __pa(0xc0008000).

 See linux/arch/arm/tools/mach-types for the complete list of machine
 numbers for r1.

 We're trying to keep crap to a minimum; DO NOT add any machine specific
 crap here - that's what the boot loader (or in extreme, well justified
 circumstances, zImage) is for.

	/*
	 * r1 = machine no, r2 = atags or dtb,
	 * r8 = phys_offset, r9 = cpuid, r10 = procinfo
	 */
	bl	__vet_atags			// ゴミデータなら r2=NULL と修正される。
#ifdef CONFIG_SMP_ON_UP
	bl	__fixup_smp
#endif
#ifdef CONFIG_ARM_PATCH_PHYS_VIRT //enable
	bl	__fixup_pv_table	//
#endif
	bl	__create_page_tables

Linux OSを用いた開発

構成

ベンダ提供

toolchain

しばらくしてわかったこと

sched_switchの出力フォーマットに関するメモ

ステータス表示

/* TRACE_CTX an TRACE_WAKE */
static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
                         char *delim)

    T = task_state_char(field->next_state);
    S = task_state_char(field->prev_state);
    trace_find_cmdline(field->next_pid, comm);
    if (!trace_seq_printf(&iter->seq,
                  " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
                  field->prev_pid,
                  field->prev_prio,
                  S, delim,
                  field->next_cpu,
                  field->next_pid,
                  field->next_prio,
                  T, comm))
        return TRACE_TYPE_PARTIAL_LINE;


static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags)
{
    return trace_ctxwake_print(iter, "==>");
}

static enum print_line_t trace_wake_print(struct trace_iterator *iter,
                      int flags)
{
    return trace_ctxwake_print(iter, "  +");
}

参照したファイル類

platform initialization

linux-2.6/arch/powerpc/kernel/cpu_setup_fsl_booke.S

_GLOBAL(__setup_cpu_e500v1)
_GLOBAL(__setup_cpu_e500v2)
	mflr	r4
	bl	__e500_icache_setup
	bl	__e500_dcache_setup
	bl	__setup_e500_ivors
	mtlr	r4
	blr

FILE: linux-2.6/arch/powerpc/kernel/cpu_setup_fsl_booke.S

/* Adjust or setup IVORs for e500v1/v2 */
_GLOBAL(__setup_e500_ivors)
	li	r3,DebugCrit@l
	mtspr	SPRN_IVOR15,r3
	li	r3,SPEUnavailable@l
	mtspr	SPRN_IVOR32,r3
	li	r3,SPEFloatingPointData@l
	mtspr	SPRN_IVOR33,r3
	li	r3,SPEFloatingPointRound@l
	mtspr	SPRN_IVOR34,r3
	li	r3,PerformanceMonitor@l
	mtspr	SPRN_IVOR35,r3
	sync
	blr

	/* Performance Monitor */
	EXCEPTION(0x2060, PerformanceMonitor, performance_monitor_exception, EXC_XFER_STD)

linux-2.6/arch/powerpc/kernel/traps.c

void performance_monitor_exception(struct pt_regs *regs)
{
	perf_irq(regs);
}

linux-2.6/arch/powerpc/kernel/pmc.c

int reserve_pmc_hardware(perf_irq_t new_perf_irq)

linux-2.6/arch/powerpc/oprofile/common.c

static void op_handle_interrupt(struct pt_regs *regs)
{
	model->handle_interrupt(regs, ctr);
}

static int op_powerpc_setup(void)
{
	/* Grab the hardware */
	err = reserve_pmc_hardware(op_handle_interrupt);

int __init oprofile_arch_init(struct oprofile_operations *ops)

		case PPC_OPROFILE_FSL_EMB:
			model = &op_model_fsl_emb;

linux-2.6/arch/powerpc/oprofile/op_model_fsl_emb.c

static void fsl_emb_handle_interrupt(struct pt_regs *regs,
				    struct op_counter_config *ctr)

linux-2.6/drivers/oprofile/cpu_buffer.c

static inline void
__oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
			  unsigned long event, int is_kernel)
{
	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(op_cpu_buffer);
	unsigned long backtrace = oprofile_backtrace_depth;

	/*
	 * if log_sample() fail we can't backtrace since we lost the
	 * source of this event
	 */
	if (!log_sample(cpu_buf, pc, backtrace, is_kernel, event))
		/* failed */
		return;

	if (!backtrace)
		return;

	oprofile_begin_trace(cpu_buf);
	oprofile_ops.backtrace(regs, backtrace);
	oprofile_end_trace(cpu_buf);
}

void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
			     unsigned long event, int is_kernel)
{
	__oprofile_add_ext_sample(pc, regs, event, is_kernel);
}

集計は？

cross compile環境の構築

$ uname -a
Linux localhost.localdomain 2.6.18-274.el5 #1 SMP Fri Jul 22 04:49:12 EDT 2011 i686 i686 i386 GNU/Linux

$ gcc --version
gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-52)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

targetとか準備

$ mkdir -p /tmp/csl_scratch/local_tools/bin
 ln -sf /usr/bin/gcc i686-pc-linux-gnu-gcc
 ln -sf /usr/bin/g++ i686-pc-linux-gnu-g++
 ln -sf /usr/bin/ar i686-pc-linux-gnu-ar
 ln -sf /usr/bin/ranlib i686-pc-linux-gnu-ranlib
 ln -sf /usr/bin/strip i686-pc-linux-gnu-strip

$ export OSS_DIR=/path/to/OSS
 ※ここは各自sourceを拾ってきたpathを設定。環境変わっても流用できるように.. 少しくらいは.

$ mkdir -p /tmp/csl_scratch/
$ cd /tmp/csl_scratch/
$ tar xf $OSS_DIR/CodeSourcery/freescale-2010.09-55-powerpc-linux-gnu.src.tar.bz2 

$ mkdir -p /tmp/csl_scratch/gnu-lite-release/src
$ cd /tmp/csl_scratch/gnu-lite-release/src
$ for f in $(ls /tmp/csl_scratch/freescale-2010.09-55-powerpc-linux-gnu/*.bz2); do tar xf $f; done

HOST環境を用意.

$ cp -a freescale-2010.09-55-powerpc-linux-gnu/freescale-2010.09-55-powerpc-linux-gnu.sh build.sh

$ sed -e 's,/scratch/froydnj,/tmp/csl_scratch,g' \
   -e 's,pushenvvar PATH /usr/local/tools/gcc-4.3.3/bin,pushenvvar PATH /tmp/csl_scratch/local_tools/bin:\$PATH,' \
   -e 's,pushenvvar LD_LIBRARY_PATH,#pushenvvar LD_LIBRARY_PATH,' \
   -e 's,rmdir ./lib/rh73,# rmdir ./lib/rh73,' \
   -e 's,/rh73/,/,' \
   -e 's/ -j4/ -j8/g' \
   -e 's,-mrh73,,' \
   -e 's,/usr/local/tools/gcc-4.3.3/bin/,/tmp/csl_scratch/local_tools/bin/,' \
   -i build.sh

tar xf $OSS_DIR/CLFS_PKG/m4-1.4.16.tar.bz2 

./configure --prefix=/tmp/csl_scratch/local_tools
make
make install

tar xf $OSS_DIR//CLFS_PKG/texinfo-4.13a.tar.gz 

./configure --prefix=/tmp/csl_scratch/local_tools
make
make install

カットアンドトライ

# task [001/258] 
# task [036/258] /i686-pc-linux-gnu/host_cleanup

task [068/258] /i686-pc-linux-gnu/toolchain/binutils/postinstall
gnu-lte-release/obj/binutil... powerpc-linux-gnu-i686-pc-linux-gnu/libiberty/functions.texi

[148/258] /i686-pc-linux-gnu/toolchain/gdb/0/build
 /tmp/csl_scratch/gnu-lite-release/obj/gdb-src-2010.09-55-powerpc-linux-gnu-i686-pc-linux-gnu/libiberty/functions.texi

task [147/258] /i686-pc-linux-gnu/toolchain/gdb/0/configure
ここからやり直すとよい.

task [158/258] /i686-pc-linux-gnu/getting_started/copy
task [159/258] /i686-pc-linux-gnu/getting_started/configure
task [160/258] /i686-pc-linux-gnu/getting_started/build
task [161/258] /i686-pc-linux-gnu/getting_started/install
task [162/258] /i686-pc-linux-gnu/csl_docbook

task [172/258] /i686-pc-linux-gnu/strip_host_objects
./build.sh: line 57432: /usr/local/tools/gcc-4.3.3/bin/i686-pc-linux-gnu-strip: No such file or directory

 task [173/258] /i686-pc-linux-gnu/strip_target_objects

task [175/258] /i686-pc-linux-gnu/package_installanywhere/unpack
task [176/258] /i686-pc-linux-gnu/package_installanywhere/merge_modules
task [177/258] /i686-pc-linux-gnu/package_installanywhere/installer
task [178/258] /i686-pc-linux-gnu/package_rpm

まとめ