Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1a527286 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Benjamin Herrenschmidt
Browse files

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
Loading
Loading
Loading
Loading
+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 */
+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;
}
+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]
+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