x86-64: Move current task from PDA to per-cpu and consolidate with 32-bit.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/arch/x86/include/asm/current.h b/arch/x86/include/asm/current.h
index 0728480..c68c361 100644
--- a/arch/x86/include/asm/current.h
+++ b/arch/x86/include/asm/current.h
@@ -1,39 +1,21 @@
#ifndef _ASM_X86_CURRENT_H
#define _ASM_X86_CURRENT_H
-#ifdef CONFIG_X86_32
#include <linux/compiler.h>
#include <asm/percpu.h>
+#ifndef __ASSEMBLY__
struct task_struct;
DECLARE_PER_CPU(struct task_struct *, current_task);
+
static __always_inline struct task_struct *get_current(void)
{
return percpu_read(current_task);
}
-#else /* X86_32 */
-
-#ifndef __ASSEMBLY__
-#include <asm/pda.h>
-
-struct task_struct;
-
-static __always_inline struct task_struct *get_current(void)
-{
- return read_pda(pcurrent);
-}
-
-#else /* __ASSEMBLY__ */
-
-#include <asm/asm-offsets.h>
-#define GET_CURRENT(reg) movq %gs:(pda_pcurrent),reg
+#define current get_current()
#endif /* __ASSEMBLY__ */
-#endif /* X86_32 */
-
-#define current get_current()
-
#endif /* _ASM_X86_CURRENT_H */
diff --git a/arch/x86/include/asm/pda.h b/arch/x86/include/asm/pda.h
index 668d5a5..7209302 100644
--- a/arch/x86/include/asm/pda.h
+++ b/arch/x86/include/asm/pda.h
@@ -11,8 +11,8 @@
/* Per processor datastructure. %gs points to it while the kernel runs */
struct x8664_pda {
- struct task_struct *pcurrent; /* 0 Current process */
- unsigned long dummy;
+ unsigned long unused1;
+ unsigned long unused2;
unsigned long kernelstack; /* 16 top of kernel stack for current */
unsigned long oldrsp; /* 24 user rsp for system call */
int irqcount; /* 32 Irq nesting counter. Starts -1 */
diff --git a/arch/x86/include/asm/system.h b/arch/x86/include/asm/system.h
index 8e626ea..4399aac 100644
--- a/arch/x86/include/asm/system.h
+++ b/arch/x86/include/asm/system.h
@@ -94,7 +94,7 @@
"call __switch_to\n\t" \
".globl thread_return\n" \
"thread_return:\n\t" \
- "movq %%gs:%P[pda_pcurrent],%%rsi\n\t" \
+ "movq "__percpu_seg_str"%P[current_task],%%rsi\n\t" \
"movq %P[thread_info](%%rsi),%%r8\n\t" \
LOCK_PREFIX "btr %[tif_fork],%P[ti_flags](%%r8)\n\t" \
"movq %%rax,%%rdi\n\t" \
@@ -106,7 +106,7 @@
[ti_flags] "i" (offsetof(struct thread_info, flags)), \
[tif_fork] "i" (TIF_FORK), \
[thread_info] "i" (offsetof(struct task_struct, stack)), \
- [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \
+ [current_task] "m" (per_cpu_var(current_task)) \
: "memory", "cc" __EXTRA_CLOBBER)
#endif