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Unverified Commit c653bd04 authored by Paul Burton's avatar Paul Burton
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MIPS: mm: Define activate_mm() using switch_mm() 



MIPS has separate definitions of activate_mm() & switch_mm() which are
identical apart from switch_mm() checking that the ASID is valid before
acquiring a new one.

We know that when activate_mm() is called cpu_context(X, mm) will be
zero, and this will never be considered a valid ASID because we never
allow the ASID version number to be zero, instead beginning with version
1 using asid_first_version(). Therefore switch_mm() will always allocate
a new ASID when called for a new task, meaning that it will behave
identically to activate_mm().

Take advantage of this to remove the duplication & define activate_mm()
using switch_mm() just like many other architectures do.

Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
parent ce680c8c

arch/mips/include/asm/mmu_context.h

+1 −27
Original line number Diff line number Diff line
@@ -166,35 +166,9 @@ static inline void destroy_context(struct mm_struct *mm) 
	dsemul_mm_cleanup(mm);

}



#define activate_mm(prev, next)	switch_mm(prev, next, current)

#define deactivate_mm(tsk, mm)	do { } while (0)



/*

 * After we have set current->mm to a new value, this activates

 * the context for the new mm so we see the new mappings.

 */

static inline void

activate_mm(struct mm_struct *prev, struct mm_struct *next)

{

	unsigned long flags;

	unsigned int cpu = smp_processor_id();



	local_irq_save(flags);



	htw_stop();

	/* Unconditionally get a new ASID.  */

	get_new_mmu_context(next, cpu);



	write_c0_entryhi(cpu_asid(cpu, next));

	TLBMISS_HANDLER_SETUP_PGD(next->pgd);



	/* mark mmu ownership change */

	cpumask_clear_cpu(cpu, mm_cpumask(prev));

	cpumask_set_cpu(cpu, mm_cpumask(next));

	htw_start();



	local_irq_restore(flags);

}



/*

 * If mm is currently active_mm, we can't really drop it.  Instead,

 * we will get a new one for it.