From 076f9776f5d8d131b36955db8641aba3893c2c1b Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 30 Jan 2008 13:33:06 +0100 Subject: [PATCH] x86: make early printk selectable on 64-bit as well Enable CONFIG_EMBEDDED to select CONFIG_EARLY_PRINTK on 64-bit as well. saves ~2K: text data bss dec hex filename 7290283 3672091 1907848 12870222 c4624e vmlinux.before 7288373 3671795 1907848 12868016 c459b0 vmlinux.after Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/Kconfig.debug | 2 +- arch/x86/kernel/head64.c | 7 ++++++- arch/x86/kernel/head_64.S | 7 +++++++ include/asm-x86/kdebug.h | 1 - include/linux/kernel.h | 3 +++ kernel/printk.c | 7 +++++++ 6 files changed, 24 insertions(+), 3 deletions(-) diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 15854b53bad..88420af9814 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -6,7 +6,7 @@ config TRACE_IRQFLAGS_SUPPORT source "lib/Kconfig.debug" config EARLY_PRINTK - bool "Early printk" if EMBEDDED && DEBUG_KERNEL && X86_32 + bool "Early printk" if EMBEDDED default y help Write kernel log output directly into the VGA buffer or to a serial diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 85c1e6bf802..87e031d4abf 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -58,8 +58,13 @@ void __init x86_64_start_kernel(char * real_mode_data) /* Make NULL pointers segfault */ zap_identity_mappings(); - for (i = 0; i < IDT_ENTRIES; i++) + for (i = 0; i < IDT_ENTRIES; i++) { +#ifdef CONFIG_EARLY_PRINTK set_intr_gate(i, &early_idt_handlers[i]); +#else + set_intr_gate(i, early_idt_handler); +#endif + } load_idt((const struct desc_ptr *)&idt_descr); early_printk("Kernel alive\n"); diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 8b4c35cb519..1d5a7a36120 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -267,6 +267,7 @@ init_rsp: bad_address: jmp bad_address +#ifdef CONFIG_EARLY_PRINTK .macro early_idt_tramp first, last .ifgt \last-\first early_idt_tramp \first, \last-1 @@ -281,8 +282,10 @@ early_idt_handlers: early_idt_tramp 64, 127 early_idt_tramp 128, 191 early_idt_tramp 192, 255 +#endif ENTRY(early_idt_handler) +#ifdef CONFIG_EARLY_PRINTK cmpl $2,early_recursion_flag(%rip) jz 1f incl early_recursion_flag(%rip) @@ -311,8 +314,11 @@ ENTRY(early_idt_handler) movq 8(%rsp),%rsi # get rip again call __print_symbol #endif +#endif /* EARLY_PRINTK */ 1: hlt jmp 1b + +#ifdef CONFIG_EARLY_PRINTK early_recursion_flag: .long 0 @@ -320,6 +326,7 @@ early_idt_msg: .asciz "PANIC: early exception %02lx rip %lx:%lx error %lx cr2 %lx\n" early_idt_ripmsg: .asciz "RIP %s\n" +#endif /* CONFIG_EARLY_PRINTK */ .balign PAGE_SIZE diff --git a/include/asm-x86/kdebug.h b/include/asm-x86/kdebug.h index a5e5e3b7eb2..e9f42d1ac38 100644 --- a/include/asm-x86/kdebug.h +++ b/include/asm-x86/kdebug.h @@ -22,7 +22,6 @@ enum die_val { DIE_PAGE_FAULT, }; -extern void early_printk(const char *fmt, ...) __attribute__((format(printf,1,2))); extern void printk_address(unsigned long address); extern void die(const char *,struct pt_regs *,long); extern int __must_check __die(const char *, struct pt_regs *, long); diff --git a/include/linux/kernel.h b/include/linux/kernel.h index a7283c9bead..ff356b2ee47 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -194,6 +194,9 @@ static inline int log_buf_read(int idx) { return 0; } static inline int log_buf_copy(char *dest, int idx, int len) { return 0; } #endif +extern void __attribute__((format(printf, 1, 2))) + early_printk(const char *fmt, ...); + unsigned long int_sqrt(unsigned long); extern int printk_ratelimit(void); diff --git a/kernel/printk.c b/kernel/printk.c index 3b7c968d0ef..58bbec68411 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -36,6 +36,13 @@ #include +/* + * Architectures can override it: + */ +void __attribute__((weak)) early_printk(const char *fmt, ...) +{ +} + #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT) /* printk's without a loglevel use this.. */ -- 2.41.1