Merge branch 'asid-allocation' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into devel-stable

This commit is contained in:
Russell King
2012-11-19 11:30:49 +00:00
3 changed files with 119 additions and 189 deletions

View File

@@ -5,18 +5,15 @@
typedef struct {
#ifdef CONFIG_CPU_HAS_ASID
unsigned int id;
raw_spinlock_t id_lock;
u64 id;
#endif
unsigned int kvm_seq;
} mm_context_t;
#ifdef CONFIG_CPU_HAS_ASID
#define ASID(mm) ((mm)->context.id & 255)
/* init_mm.context.id_lock should be initialized. */
#define INIT_MM_CONTEXT(name) \
.context.id_lock = __RAW_SPIN_LOCK_UNLOCKED(name.context.id_lock),
#define ASID_BITS 8
#define ASID_MASK ((~0ULL) << ASID_BITS)
#define ASID(mm) ((mm)->context.id & ~ASID_MASK)
#else
#define ASID(mm) (0)
#endif

View File

@@ -24,84 +24,8 @@ void __check_kvm_seq(struct mm_struct *mm);
#ifdef CONFIG_CPU_HAS_ASID
/*
* On ARMv6, we have the following structure in the Context ID:
*
* 31 7 0
* +-------------------------+-----------+
* | process ID | ASID |
* +-------------------------+-----------+
* | context ID |
* +-------------------------------------+
*
* The ASID is used to tag entries in the CPU caches and TLBs.
* The context ID is used by debuggers and trace logic, and
* should be unique within all running processes.
*/
#define ASID_BITS 8
#define ASID_MASK ((~0) << ASID_BITS)
#define ASID_FIRST_VERSION (1 << ASID_BITS)
extern unsigned int cpu_last_asid;
void __init_new_context(struct task_struct *tsk, struct mm_struct *mm);
void __new_context(struct mm_struct *mm);
void cpu_set_reserved_ttbr0(void);
static inline void switch_new_context(struct mm_struct *mm)
{
unsigned long flags;
__new_context(mm);
local_irq_save(flags);
cpu_switch_mm(mm->pgd, mm);
local_irq_restore(flags);
}
static inline void check_and_switch_context(struct mm_struct *mm,
struct task_struct *tsk)
{
if (unlikely(mm->context.kvm_seq != init_mm.context.kvm_seq))
__check_kvm_seq(mm);
/*
* Required during context switch to avoid speculative page table
* walking with the wrong TTBR.
*/
cpu_set_reserved_ttbr0();
if (!((mm->context.id ^ cpu_last_asid) >> ASID_BITS))
/*
* The ASID is from the current generation, just switch to the
* new pgd. This condition is only true for calls from
* context_switch() and interrupts are already disabled.
*/
cpu_switch_mm(mm->pgd, mm);
else if (irqs_disabled())
/*
* Defer the new ASID allocation until after the context
* switch critical region since __new_context() cannot be
* called with interrupts disabled (it sends IPIs).
*/
set_ti_thread_flag(task_thread_info(tsk), TIF_SWITCH_MM);
else
/*
* That is a direct call to switch_mm() or activate_mm() with
* interrupts enabled and a new context.
*/
switch_new_context(mm);
}
#define init_new_context(tsk,mm) (__init_new_context(tsk,mm),0)
#define finish_arch_post_lock_switch \
finish_arch_post_lock_switch
static inline void finish_arch_post_lock_switch(void)
{
if (test_and_clear_thread_flag(TIF_SWITCH_MM))
switch_new_context(current->mm);
}
void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk);
#define init_new_context(tsk,mm) ({ mm->context.id = 0; })
#else /* !CONFIG_CPU_HAS_ASID */
@@ -143,6 +67,7 @@ static inline void finish_arch_post_lock_switch(void)
#endif /* CONFIG_CPU_HAS_ASID */
#define destroy_context(mm) do { } while(0)
#define activate_mm(prev,next) switch_mm(prev, next, NULL)
/*
* This is called when "tsk" is about to enter lazy TLB mode.
@@ -186,6 +111,5 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next,
}
#define deactivate_mm(tsk,mm) do { } while (0)
#define activate_mm(prev,next) switch_mm(prev, next, NULL)
#endif