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Commit 1a527286 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Benjamin Herrenschmidt
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powerpc: Optimize hugepage invalidate 



Hugepage invalidate involves invalidating multiple hpte entries.
Optimize the operation using H_BULK_REMOVE on lpar platforms.
On native, reduce the number of tlb flush.

Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 437d4964

arch/powerpc/include/asm/machdep.h

+3 −0
Original line number Diff line number Diff line
@@ -57,6 +57,9 @@ struct machdep_calls { 
	void            (*hpte_removebolted)(unsigned long ea,

					     int psize, int ssize);

	void		(*flush_hash_range)(unsigned long number, int local);

	void		(*hugepage_invalidate)(struct mm_struct *mm,

					       unsigned char *hpte_slot_array,

					       unsigned long addr, int psize);



	/* special for kexec, to be called in real mode, linear mapping is

	 * destroyed as well */

arch/powerpc/mm/hash_native_64.c

+73 −0
Original line number Diff line number Diff line
@@ -407,6 +407,78 @@ static void native_hpte_invalidate(unsigned long slot, unsigned long vpn, 
	local_irq_restore(flags);

}



static void native_hugepage_invalidate(struct mm_struct *mm,

				       unsigned char *hpte_slot_array,

				       unsigned long addr, int psize)

{

	int ssize = 0, i;

	int lock_tlbie;

	struct hash_pte *hptep;

	int actual_psize = MMU_PAGE_16M;

	unsigned int max_hpte_count, valid;

	unsigned long flags, s_addr = addr;

	unsigned long hpte_v, want_v, shift;

	unsigned long hidx, vpn = 0, vsid, hash, slot;



	shift = mmu_psize_defs[psize].shift;

	max_hpte_count = 1U << (PMD_SHIFT - shift);



	local_irq_save(flags);

	for (i = 0; i < max_hpte_count; i++) {

		valid = hpte_valid(hpte_slot_array, i);

		if (!valid)

			continue;

		hidx =  hpte_hash_index(hpte_slot_array, i);



		/* get the vpn */

		addr = s_addr + (i * (1ul << shift));

		if (!is_kernel_addr(addr)) {

			ssize = user_segment_size(addr);

			vsid = get_vsid(mm->context.id, addr, ssize);

			WARN_ON(vsid == 0);

		} else {

			vsid = get_kernel_vsid(addr, mmu_kernel_ssize);

			ssize = mmu_kernel_ssize;

		}



		vpn = hpt_vpn(addr, vsid, ssize);

		hash = hpt_hash(vpn, shift, ssize);

		if (hidx & _PTEIDX_SECONDARY)

			hash = ~hash;



		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;

		slot += hidx & _PTEIDX_GROUP_IX;



		hptep = htab_address + slot;

		want_v = hpte_encode_avpn(vpn, psize, ssize);

		native_lock_hpte(hptep);

		hpte_v = hptep->v;



		/* Even if we miss, we need to invalidate the TLB */

		if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))

			native_unlock_hpte(hptep);

		else

			/* Invalidate the hpte. NOTE: this also unlocks it */

			hptep->v = 0;

	}

	/*

	 * Since this is a hugepage, we just need a single tlbie.

	 * use the last vpn.

	 */

	lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);

	if (lock_tlbie)

		raw_spin_lock(&native_tlbie_lock);



	asm volatile("ptesync":::"memory");

	__tlbie(vpn, psize, actual_psize, ssize);

	asm volatile("eieio; tlbsync; ptesync":::"memory");



	if (lock_tlbie)

		raw_spin_unlock(&native_tlbie_lock);



	local_irq_restore(flags);

}



static inline int __hpte_actual_psize(unsigned int lp, int psize)

{

	int i, shift;
@@ -640,4 +712,5 @@ void __init hpte_init_native(void) 
	ppc_md.hpte_remove	= native_hpte_remove;

	ppc_md.hpte_clear_all	= native_hpte_clear;

	ppc_md.flush_hash_range = native_flush_hash_range;

	ppc_md.hugepage_invalidate   = native_hugepage_invalidate;

}

arch/powerpc/mm/pgtable_64.c

+10 −2
Original line number Diff line number Diff line
@@ -708,6 +708,7 @@ void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr, 
{

	int ssize, i;

	unsigned long s_addr;

	int max_hpte_count;

	unsigned int psize, valid;

	unsigned char *hpte_slot_array;

	unsigned long hidx, vpn, vsid, hash, shift, slot;
@@ -727,9 +728,16 @@ void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr, 


	/* get the base page size */

	psize = get_slice_psize(mm, s_addr);

	shift = mmu_psize_defs[psize].shift;



	for (i = 0; i < (HPAGE_PMD_SIZE >> shift); i++) {

	if (ppc_md.hugepage_invalidate)

		return ppc_md.hugepage_invalidate(mm, hpte_slot_array,

						  s_addr, psize);

	/*

	 * No bluk hpte removal support, invalidate each entry

	 */

	shift = mmu_psize_defs[psize].shift;

	max_hpte_count = HPAGE_PMD_SIZE >> shift;

	for (i = 0; i < max_hpte_count; i++) {

		/*

		 * 8 bits per each hpte entries

		 * 000| [ secondary group (one bit) | hidx (3 bits) | valid bit]

arch/powerpc/platforms/pseries/lpar.c

+115 −7
Original line number Diff line number Diff line
@@ -45,6 +45,13 @@ 
#include "plpar_wrappers.h"

#include "pseries.h"



/* Flag bits for H_BULK_REMOVE */

#define HBR_REQUEST	0x4000000000000000UL

#define HBR_RESPONSE	0x8000000000000000UL

#define HBR_END		0xc000000000000000UL

#define HBR_AVPN	0x0200000000000000UL

#define HBR_ANDCOND	0x0100000000000000UL





/* in hvCall.S */

EXPORT_SYMBOL(plpar_hcall);
@@ -347,6 +354,113 @@ static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long vpn, 
	BUG_ON(lpar_rc != H_SUCCESS);

}



/*

 * Limit iterations holding pSeries_lpar_tlbie_lock to 3. We also need

 * to make sure that we avoid bouncing the hypervisor tlbie lock.

 */

#define PPC64_HUGE_HPTE_BATCH 12



static void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,

					     unsigned long *vpn, int count,

					     int psize, int ssize)

{

	unsigned long param[8];

	int i = 0, pix = 0, rc;

	unsigned long flags = 0;

	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);



	if (lock_tlbie)

		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);



	for (i = 0; i < count; i++) {



		if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {

			pSeries_lpar_hpte_invalidate(slot[i], vpn[i], psize, 0,

						     ssize, 0);

		} else {

			param[pix] = HBR_REQUEST | HBR_AVPN | slot[i];

			param[pix+1] = hpte_encode_avpn(vpn[i], psize, ssize);

			pix += 2;

			if (pix == 8) {

				rc = plpar_hcall9(H_BULK_REMOVE, param,

						  param[0], param[1], param[2],

						  param[3], param[4], param[5],

						  param[6], param[7]);

				BUG_ON(rc != H_SUCCESS);

				pix = 0;

			}

		}

	}

	if (pix) {

		param[pix] = HBR_END;

		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],

				  param[2], param[3], param[4], param[5],

				  param[6], param[7]);

		BUG_ON(rc != H_SUCCESS);

	}



	if (lock_tlbie)

		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);

}



static void pSeries_lpar_hugepage_invalidate(struct mm_struct *mm,

				       unsigned char *hpte_slot_array,

				       unsigned long addr, int psize)

{

	int ssize = 0, i, index = 0;

	unsigned long s_addr = addr;

	unsigned int max_hpte_count, valid;

	unsigned long vpn_array[PPC64_HUGE_HPTE_BATCH];

	unsigned long slot_array[PPC64_HUGE_HPTE_BATCH];

	unsigned long shift, hidx, vpn = 0, vsid, hash, slot;



	shift = mmu_psize_defs[psize].shift;

	max_hpte_count = 1U << (PMD_SHIFT - shift);



	for (i = 0; i < max_hpte_count; i++) {

		valid = hpte_valid(hpte_slot_array, i);

		if (!valid)

			continue;

		hidx =  hpte_hash_index(hpte_slot_array, i);



		/* get the vpn */

		addr = s_addr + (i * (1ul << shift));

		if (!is_kernel_addr(addr)) {

			ssize = user_segment_size(addr);

			vsid = get_vsid(mm->context.id, addr, ssize);

			WARN_ON(vsid == 0);

		} else {

			vsid = get_kernel_vsid(addr, mmu_kernel_ssize);

			ssize = mmu_kernel_ssize;

		}



		vpn = hpt_vpn(addr, vsid, ssize);

		hash = hpt_hash(vpn, shift, ssize);

		if (hidx & _PTEIDX_SECONDARY)

			hash = ~hash;



		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;

		slot += hidx & _PTEIDX_GROUP_IX;



		slot_array[index] = slot;

		vpn_array[index] = vpn;

		if (index == PPC64_HUGE_HPTE_BATCH - 1) {

			/*

			 * Now do a bluk invalidate

			 */

			__pSeries_lpar_hugepage_invalidate(slot_array,

							   vpn_array,

							   PPC64_HUGE_HPTE_BATCH,

							   psize, ssize);

			index = 0;

		} else

			index++;

	}

	if (index)

		__pSeries_lpar_hugepage_invalidate(slot_array, vpn_array,

						   index, psize, ssize);

}



static void pSeries_lpar_hpte_removebolted(unsigned long ea,

					   int psize, int ssize)

{
@@ -364,13 +478,6 @@ static void pSeries_lpar_hpte_removebolted(unsigned long ea, 
	pSeries_lpar_hpte_invalidate(slot, vpn, psize, 0, ssize, 0);

}



/* Flag bits for H_BULK_REMOVE */

#define HBR_REQUEST	0x4000000000000000UL

#define HBR_RESPONSE	0x8000000000000000UL

#define HBR_END		0xc000000000000000UL

#define HBR_AVPN	0x0200000000000000UL

#define HBR_ANDCOND	0x0100000000000000UL



/*

 * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie

 * lock.
@@ -459,6 +566,7 @@ void __init hpte_init_lpar(void) 
	ppc_md.hpte_removebolted = pSeries_lpar_hpte_removebolted;

	ppc_md.flush_hash_range	= pSeries_lpar_flush_hash_range;

	ppc_md.hpte_clear_all   = pSeries_lpar_hptab_clear;

	ppc_md.hugepage_invalidate = pSeries_lpar_hugepage_invalidate;

}



#ifdef CONFIG_PPC_SMLPAR