powerpc/64s: Allocate LPPACAs individually (499dcd41) · Commits · e / devices / android_kernel_fairphone_FP4

arch/powerpc/include/asm/lppaca.h

+12 −12

Original line number	Diff line number	Diff line
		@@ -36,14 +36,16 @@
		#include <asm/mmu.h>

		/*
		* We only have to have statically allocated lppaca structs on
		* legacy iSeries, which supports at most 64 cpus.
		*/
		#define NR_LPPACAS 1

		/*
		* The Hypervisor barfs if the lppaca crosses a page boundary. A 1k
		* alignment is sufficient to prevent this
		* The lppaca is the "virtual processor area" registered with the hypervisor,
		* H_REGISTER_VPA etc.
		*
		* According to PAPR, the structure is 640 bytes long, must be L1 cache line
		* aligned, and must not cross a 4kB boundary. Its size field must be at
		* least 640 bytes (but may be more).
		*
		* Pre-v4.14 KVM hypervisors reject the VPA if its size field is smaller than
		* 1kB, so we dynamically allocate 1kB and advertise size as 1kB, but keep
		* this structure as the canonical 640 byte size.
		*/
		struct lppaca {
		/* cacheline 1 contains read-only data */
		@@ -99,9 +101,7 @@ struct lppaca {
		u8 reserved11[148];
		volatile __be64 dtl_idx; /* Dispatch Trace Log head index */
		u8 reserved12[96];
		} __attribute__((__aligned__(0x400)));

		extern struct lppaca lppaca[];
		} ____cacheline_aligned;

		#define lppaca_of(cpu) (*paca_ptrs[cpu]->lppaca_ptr)

arch/powerpc/kernel/machine_kexec_64.c

+11 −4

Original line number	Diff line number	Diff line
		@@ -323,17 +323,24 @@ void default_machine_kexec(struct kimage *image)
		kexec_stack.thread_info.cpu = current_thread_info()->cpu;

		/* We need a static PACA, too; copy this CPU's PACA over and switch to
		* it. Also poison per_cpu_offset to catch anyone using non-static
		* data.
		* it. Also poison per_cpu_offset and NULL lppaca to catch anyone using
		* non-static data.
		*/
		memcpy(&kexec_paca, get_paca(), sizeof(struct paca_struct));
		kexec_paca.data_offset = 0xedeaddeadeeeeeeeUL;
		#ifdef CONFIG_PPC_PSERIES
		kexec_paca.lppaca_ptr = NULL;
		#endif
		paca_ptrs[kexec_paca.paca_index] = &kexec_paca;

		setup_paca(&kexec_paca);

		/* XXX: If anyone does 'dynamic lppacas' this will also need to be
		* switched to a static version!
		/*
		* The lppaca should be unregistered at this point so the HV won't
		* touch it. In the case of a crash, none of the lppacas are
		* unregistered so there is not much we can do about it here.
		*/

		/*
		* On Book3S, the copy must happen with the MMU off if we are either
		* using Radix page tables or we are not in an LPAR since we can

arch/powerpc/kernel/paca.c

+30 −59

Original line number	Diff line number	Diff line
		@@ -23,82 +23,50 @@
		#ifdef CONFIG_PPC_PSERIES

		/*
		* The structure which the hypervisor knows about - this structure
		* should not cross a page boundary. The vpa_init/register_vpa call
		* is now known to fail if the lppaca structure crosses a page
		* boundary. The lppaca is also used on POWER5 pSeries boxes.
		* The lppaca is 640 bytes long, and cannot readily
		* change since the hypervisor knows its layout, so a 1kB alignment
		* will suffice to ensure that it doesn't cross a page boundary.
		* See asm/lppaca.h for more detail.
		*
		* lppaca structures must must be 1kB in size, L1 cache line aligned,
		* and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy
		* these requirements.
		*/
		struct lppaca lppaca[] = {
		[0 ... (NR_LPPACAS-1)] = {
		static inline void init_lppaca(struct lppaca *lppaca)
		{
		BUILD_BUG_ON(sizeof(struct lppaca) != 640);

		*lppaca = (struct lppaca) {
		.desc = cpu_to_be32(0xd397d781), /* "LpPa" */
		.size = cpu_to_be16(sizeof(struct lppaca)),
		.size = cpu_to_be16(0x400),
		.fpregs_in_use = 1,
		.slb_count = cpu_to_be16(64),
		.vmxregs_in_use = 0,
		.page_ins = 0,
		},
		.page_ins = 0, };
		};

		static struct lppaca *extra_lppacas;
		static long __initdata lppaca_size;

		static void __init allocate_lppacas(int nr_cpus, unsigned long limit)
		{
		if (early_cpu_has_feature(CPU_FTR_HVMODE))
		return;

		if (nr_cpus <= NR_LPPACAS)
		return;

		lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) *
		(nr_cpus - NR_LPPACAS));
		extra_lppacas = __va(memblock_alloc_base(lppaca_size,
		PAGE_SIZE, limit));
		}

		static struct lppaca * __init new_lppaca(int cpu)
		static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
		{
		struct lppaca *lp;
		size_t size = 0x400;

		BUILD_BUG_ON(size < sizeof(struct lppaca));

		if (early_cpu_has_feature(CPU_FTR_HVMODE))
		return NULL;

		if (cpu < NR_LPPACAS)
		return &lppaca[cpu];

		lp = extra_lppacas + (cpu - NR_LPPACAS);
		*lp = lppaca[0];
		lp = __va(memblock_alloc_base(size, 0x400, limit));
		init_lppaca(lp);

		return lp;
		}

		static void __init free_lppacas(void)
		static void __init free_lppaca(struct lppaca *lp)
		{
		long new_size = 0, nr;
		size_t size = 0x400;

		if (early_cpu_has_feature(CPU_FTR_HVMODE))
		return;

		if (!lppaca_size)
		return;
		nr = num_possible_cpus() - NR_LPPACAS;
		if (nr > 0)
		new_size = PAGE_ALIGN(nr * sizeof(struct lppaca));
		if (new_size >= lppaca_size)
		return;

		memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size);
		lppaca_size = new_size;
		memblock_free(__pa(lp), size);
		}

		#else

		static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { }
		static inline void free_lppacas(void) { }

		#endif /* CONFIG_PPC_BOOK3S */

		#ifdef CONFIG_PPC_BOOK3S_64
		@@ -167,7 +135,7 @@ EXPORT_SYMBOL(paca_ptrs);
		void __init initialise_paca(struct paca_struct *new_paca, int cpu)
		{
		#ifdef CONFIG_PPC_PSERIES
		new_paca->lppaca_ptr = new_lppaca(cpu);
		new_paca->lppaca_ptr = NULL;
		#endif
		#ifdef CONFIG_PPC_BOOK3E
		new_paca->kernel_pgd = swapper_pg_dir;
		@@ -254,13 +222,15 @@ void __init allocate_pacas(void)
		printk(KERN_DEBUG "Allocated %lu bytes for %u pacas\n",
		size, nr_cpu_ids);

		allocate_lppacas(nr_cpu_ids, limit);

		allocate_slb_shadows(nr_cpu_ids, limit);

		/* Can't use for_each__cpu, as they aren't functional yet /
		for (cpu = 0; cpu < nr_cpu_ids; cpu++)
		for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
		initialise_paca(paca_ptrs[cpu], cpu);
		#ifdef CONFIG_PPC_PSERIES
		paca_ptrs[cpu]->lppaca_ptr = new_lppaca(cpu, limit);
		#endif
		}
		}

		void __init free_unused_pacas(void)
		@@ -272,6 +242,9 @@ void __init free_unused_pacas(void)
		for (cpu = 0; cpu < paca_nr_cpu_ids; cpu++) {
		if (!cpu_possible(cpu)) {
		unsigned long pa = __pa(paca_ptrs[cpu]);
		#ifdef CONFIG_PPC_PSERIES
		free_lppaca(paca_ptrs[cpu]->lppaca_ptr);
		#endif
		memblock_free(pa, sizeof(struct paca_struct));
		paca_ptrs[cpu] = NULL;
		size += sizeof(struct paca_struct);
		@@ -288,8 +261,6 @@ void __init free_unused_pacas(void)
		if (size)
		printk(KERN_DEBUG "Freed %lu bytes for unused pacas\n", size);

		free_lppacas();

		paca_nr_cpu_ids = nr_cpu_ids;
		paca_ptrs_size = new_ptrs_size;
		}

arch/powerpc/kvm/book3s_hv.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -498,7 +498,8 @@ static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu,
		* use 640 bytes of the structure though, so we should accept
		* clients that set a size of 640.
		*/
		if (len < 640)
		BUILD_BUG_ON(sizeof(struct lppaca) != 640);
		if (len < sizeof(struct lppaca))
		break;
		vpap = &tvcpu->arch.vpa;
		err = 0;

arch/powerpc/mm/numa.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1110,7 +1110,7 @@ static void setup_cpu_associativity_change_counters(void)
		for_each_possible_cpu(cpu) {
		int i;
		u8 *counts = vphn_cpu_change_counts[cpu];
		volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts;
		volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts;

		for (i = 0; i < distance_ref_points_depth; i++)
		counts[i] = hypervisor_counts[i];
		@@ -1136,7 +1136,7 @@ static int update_cpu_associativity_changes_mask(void)
		for_each_possible_cpu(cpu) {
		int i, changed = 0;
		u8 *counts = vphn_cpu_change_counts[cpu];
		volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts;
		volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts;

		for (i = 0; i < distance_ref_points_depth; i++) {
		if (hypervisor_counts[i] != counts[i]) {