x86-32: Allocate irq stacks seperate from percpu area

The percpu allocator cannot handle alignments larger than one
page. Allocate the irq stacks seperately, and only keep the
pointers as percpu data.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tj@kernel.org
LKML-Reference: <1288158182-1753-1-git-send-email-brgerst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h
index 0bf5b00836502fb6512609bbad05fbc3eaa96320..13b0ebaa512f77764e06956632b32755f8ca2bfa 100644 (file)
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -21,10 +21,8 @@ static inline int irq_canonicalize(int irq)
 
 #ifdef CONFIG_X86_32
 extern void irq_ctx_init(int cpu);
-extern void irq_ctx_exit(int cpu);
 #else
 # define irq_ctx_init(cpu) do { } while (0)
-# define irq_ctx_exit(cpu) do { } while (0)
 #endif
 
 #define __ARCH_HAS_DO_SOFTIRQ

diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 50fbbe60e5074efcc11600616e32e21e3ca31551..64668dbf00a46185f7ef9d96a6a58996509e523d 100644 (file)
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -60,9 +60,6 @@ union irq_ctx {
 static DEFINE_PER_CPU(union irq_ctx *, hardirq_ctx);
 static DEFINE_PER_CPU(union irq_ctx *, softirq_ctx);
 
-static DEFINE_PER_CPU_MULTIPAGE_ALIGNED(union irq_ctx, hardirq_stack, THREAD_SIZE);
-static DEFINE_PER_CPU_MULTIPAGE_ALIGNED(union irq_ctx, softirq_stack, THREAD_SIZE);
-
 static void call_on_stack(void *func, void *stack)
 {
        asm volatile("xchgl     %%ebx,%%esp     \n"
@@ -128,7 +125,7 @@ void __cpuinit irq_ctx_init(int cpu)
        if (per_cpu(hardirq_ctx, cpu))
                return;
 
-       irqctx = &per_cpu(hardirq_stack, cpu);
+       irqctx = (union irq_ctx *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER);
        irqctx->tinfo.task              = NULL;
        irqctx->tinfo.exec_domain       = NULL;
        irqctx->tinfo.cpu               = cpu;
@@ -137,7 +134,7 @@ void __cpuinit irq_ctx_init(int cpu)
 
        per_cpu(hardirq_ctx, cpu) = irqctx;
 
-       irqctx = &per_cpu(softirq_stack, cpu);
+       irqctx = (union irq_ctx *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER);
        irqctx->tinfo.task              = NULL;
        irqctx->tinfo.exec_domain       = NULL;
        irqctx->tinfo.cpu               = cpu;
@@ -150,11 +147,6 @@ void __cpuinit irq_ctx_init(int cpu)
               cpu, per_cpu(hardirq_ctx, cpu),  per_cpu(softirq_ctx, cpu));
 }
 
-void irq_ctx_exit(int cpu)
-{
-       per_cpu(hardirq_ctx, cpu) = NULL;
-}
-
 asmlinkage void do_softirq(void)
 {
        unsigned long flags;

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 6af118511b4a56fde1ee915162d2013c61e3d7b2..90baf567bbf71a3e2d5adedb1e13ceda5a851e42 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1373,7 +1373,6 @@ void play_dead_common(void)
 {
        idle_task_exit();
        reset_lazy_tlbstate();
-       irq_ctx_exit(raw_smp_processor_id());
        c1e_remove_cpu(raw_smp_processor_id());
 
        mb();