From 26f80bd6a9ab17bc8a60b6092e7c0d05c5927ce5 Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Mon, 19 Jan 2009 00:38:58 +0900 Subject: [PATCH] x86-64: Convert irqstacks to per-cpu Move the irqstackptr variable from the PDA to per-cpu. Make the stacks themselves per-cpu, removing some specific allocation code. Add a seperate flag (is_boot_cpu) to simplify the per-cpu boot adjustments. tj: * sprinkle some underbars around. * irq_stack_ptr is not used till traps_init(), no reason to initialize it early. On SMP, just leaving it NULL till proper initialization in setup_per_cpu_areas() works. Dropped is_boot_cpu and early irq_stack_ptr initialization. * do DECLARE/DEFINE_PER_CPU(char[IRQ_STACK_SIZE], irq_stack) instead of (char, irq_stack[IRQ_STACK_SIZE]). Signed-off-by: Brian Gerst Signed-off-by: Tejun Heo --- arch/x86/include/asm/page_64.h | 4 ++-- arch/x86/include/asm/pda.h | 1 - arch/x86/include/asm/processor.h | 3 +++ arch/x86/kernel/asm-offsets_64.c | 1 - arch/x86/kernel/cpu/common.c | 19 +++++++----------- arch/x86/kernel/dumpstack_64.c | 33 ++++++++++++++++---------------- arch/x86/kernel/entry_64.S | 6 +++--- arch/x86/kernel/setup_percpu.c | 4 +++- 8 files changed, 35 insertions(+), 36 deletions(-) diff --git a/arch/x86/include/asm/page_64.h b/arch/x86/include/asm/page_64.h index 5ebca29f44f..e27fdbe5f9e 100644 --- a/arch/x86/include/asm/page_64.h +++ b/arch/x86/include/asm/page_64.h @@ -13,8 +13,8 @@ #define DEBUG_STACK_ORDER (EXCEPTION_STACK_ORDER + 1) #define DEBUG_STKSZ (PAGE_SIZE << DEBUG_STACK_ORDER) -#define IRQSTACK_ORDER 2 -#define IRQSTACKSIZE (PAGE_SIZE << IRQSTACK_ORDER) +#define IRQ_STACK_ORDER 2 +#define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER) #define STACKFAULT_STACK 1 #define DOUBLEFAULT_STACK 2 diff --git a/arch/x86/include/asm/pda.h b/arch/x86/include/asm/pda.h index 8ee835ed10e..09965f7a216 100644 --- a/arch/x86/include/asm/pda.h +++ b/arch/x86/include/asm/pda.h @@ -22,7 +22,6 @@ struct x8664_pda { /* gcc-ABI: this canary MUST be at offset 40!!! */ #endif - char *irqstackptr; short nodenumber; /* number of current node (32k max) */ short in_bootmem; /* pda lives in bootmem */ short isidle; diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 091cd8855f2..f511246fa6c 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -378,6 +378,9 @@ union thread_xstate { #ifdef CONFIG_X86_64 DECLARE_PER_CPU(struct orig_ist, orig_ist); + +DECLARE_PER_CPU(char[IRQ_STACK_SIZE], irq_stack); +DECLARE_PER_CPU(char *, irq_stack_ptr); #endif extern void print_cpu_info(struct cpuinfo_x86 *); diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index f4cc81bfbf8..5b821fbdaf7 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -54,7 +54,6 @@ int main(void) ENTRY(pcurrent); ENTRY(irqcount); ENTRY(cpunumber); - ENTRY(irqstackptr); DEFINE(pda_size, sizeof(struct x8664_pda)); BLANK(); #undef ENTRY diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 3d0cc6f1711..496f0a01919 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -881,7 +881,13 @@ __setup("clearcpuid=", setup_disablecpuid); #ifdef CONFIG_X86_64 struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table }; -static char boot_cpu_stack[IRQSTACKSIZE] __page_aligned_bss; +DEFINE_PER_CPU_PAGE_ALIGNED(char[IRQ_STACK_SIZE], irq_stack); +#ifdef CONFIG_SMP +DEFINE_PER_CPU(char *, irq_stack_ptr); /* will be set during per cpu init */ +#else +DEFINE_PER_CPU(char *, irq_stack_ptr) = + per_cpu_var(irq_stack) + IRQ_STACK_SIZE - 64; +#endif void __cpuinit pda_init(int cpu) { @@ -901,18 +907,7 @@ void __cpuinit pda_init(int cpu) if (cpu == 0) { /* others are initialized in smpboot.c */ pda->pcurrent = &init_task; - pda->irqstackptr = boot_cpu_stack; - pda->irqstackptr += IRQSTACKSIZE - 64; } else { - if (!pda->irqstackptr) { - pda->irqstackptr = (char *) - __get_free_pages(GFP_ATOMIC, IRQSTACK_ORDER); - if (!pda->irqstackptr) - panic("cannot allocate irqstack for cpu %d", - cpu); - pda->irqstackptr += IRQSTACKSIZE - 64; - } - if (pda->nodenumber == 0 && cpu_to_node(cpu) != NUMA_NO_NODE) pda->nodenumber = cpu_to_node(cpu); } diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index c302d070704..28e26a4315d 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -106,7 +106,8 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, const struct stacktrace_ops *ops, void *data) { const unsigned cpu = get_cpu(); - unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr; + unsigned long *irq_stack_end = + (unsigned long *)per_cpu(irq_stack_ptr, cpu); unsigned used = 0; struct thread_info *tinfo; int graph = 0; @@ -160,23 +161,23 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, stack = (unsigned long *) estack_end[-2]; continue; } - if (irqstack_end) { - unsigned long *irqstack; - irqstack = irqstack_end - - (IRQSTACKSIZE - 64) / sizeof(*irqstack); + if (irq_stack_end) { + unsigned long *irq_stack; + irq_stack = irq_stack_end - + (IRQ_STACK_SIZE - 64) / sizeof(*irq_stack); - if (stack >= irqstack && stack < irqstack_end) { + if (stack >= irq_stack && stack < irq_stack_end) { if (ops->stack(data, "IRQ") < 0) break; bp = print_context_stack(tinfo, stack, bp, - ops, data, irqstack_end, &graph); + ops, data, irq_stack_end, &graph); /* * We link to the next stack (which would be * the process stack normally) the last * pointer (index -1 to end) in the IRQ stack: */ - stack = (unsigned long *) (irqstack_end[-1]); - irqstack_end = NULL; + stack = (unsigned long *) (irq_stack_end[-1]); + irq_stack_end = NULL; ops->stack(data, "EOI"); continue; } @@ -199,10 +200,10 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, unsigned long *stack; int i; const int cpu = smp_processor_id(); - unsigned long *irqstack_end = - (unsigned long *) (cpu_pda(cpu)->irqstackptr); - unsigned long *irqstack = - (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE); + unsigned long *irq_stack_end = + (unsigned long *)(per_cpu(irq_stack_ptr, cpu)); + unsigned long *irq_stack = + (unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE); /* * debugging aid: "show_stack(NULL, NULL);" prints the @@ -218,9 +219,9 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, stack = sp; for (i = 0; i < kstack_depth_to_print; i++) { - if (stack >= irqstack && stack <= irqstack_end) { - if (stack == irqstack_end) { - stack = (unsigned long *) (irqstack_end[-1]); + if (stack >= irq_stack && stack <= irq_stack_end) { + if (stack == irq_stack_end) { + stack = (unsigned long *) (irq_stack_end[-1]); printk(" "); } } else { diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 4833f3a1965..d22677a6643 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -345,7 +345,7 @@ ENTRY(save_args) 1: incl %gs:pda_irqcount jne 2f popq_cfi %rax /* move return address... */ - mov %gs:pda_irqstackptr,%rsp + mov PER_CPU_VAR(irq_stack_ptr),%rsp EMPTY_FRAME 0 pushq_cfi %rax /* ... to the new stack */ /* @@ -1261,7 +1261,7 @@ ENTRY(call_softirq) mov %rsp,%rbp CFI_DEF_CFA_REGISTER rbp incl %gs:pda_irqcount - cmove %gs:pda_irqstackptr,%rsp + cmove PER_CPU_VAR(irq_stack_ptr),%rsp push %rbp # backlink for old unwinder call __do_softirq leaveq @@ -1300,7 +1300,7 @@ ENTRY(xen_do_hypervisor_callback) # do_hypervisor_callback(struct *pt_regs) 11: incl %gs:pda_irqcount movq %rsp,%rbp CFI_DEF_CFA_REGISTER rbp - cmovzq %gs:pda_irqstackptr,%rsp + cmovzq PER_CPU_VAR(irq_stack_ptr),%rsp pushq %rbp # backlink for old unwinder call xen_evtchn_do_upcall popq %rsp diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index b5c35af2011..8b53ef83c61 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -192,7 +192,10 @@ void __init setup_per_cpu_areas(void) memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start); per_cpu_offset(cpu) = ptr - __per_cpu_start; + per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu); #ifdef CONFIG_X86_64 + per_cpu(irq_stack_ptr, cpu) = + (char *)per_cpu(irq_stack, cpu) + IRQ_STACK_SIZE - 64; /* * CPU0 modified pda in the init data area, reload pda * offset for CPU0 and clear the area for others. @@ -202,7 +205,6 @@ void __init setup_per_cpu_areas(void) else memset(cpu_pda(cpu), 0, sizeof(*cpu_pda(cpu))); #endif - per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu); DBG("PERCPU: cpu %4d %p\n", cpu, ptr); } -- 2.39.2