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Add per-CPU caches to the pmemrange allocator.

The caches are used primarily to reduce contention on uvm_lock_fpageq() during
concurrent page faults.  For the moment only uvm_pagealloc() tries to get a
page from the current CPU's cache.  So on some architectures the caches are
also used by the pmap layer.

Each cache is composed of two magazines, design is borrowed from jeff bonwick
vmem's paper and the implementation is similar to the one of pool_cache from
dlg@.  However there is no depot layer and magazines are refilled directly by
the pmemrange allocator.

This version includes splvm()/splx() dances because the buffer cache flips
buffers in interrupt context.  So we have to prevent recursive accesses to
per-CPU magazines.

Tested by naddy@, solene@, krw@, robert@, claudio@ and Laurence Tratt.

ok claudio@, kettenis@

/*	$OpenBSD: uvmexp.h,v 1.15 2024/05/01 12:54:27 mpi Exp $	*/

#ifndef	_UVM_UVMEXP_
#define	_UVM_UVMEXP_

/*
 * CTL_VM identifiers
 */
#define	VM_METER	1		/* struct vmmeter */
#define	VM_LOADAVG	2		/* struct loadavg */
#define	VM_PSSTRINGS	3		/* PSSTRINGS */
#define VM_UVMEXP	4		/* struct uvmexp */
#define VM_SWAPENCRYPT	5		/* int */
#define VM_NKMEMPAGES	6		/* int - # kmem_map pages */
#define	VM_ANONMIN	7
#define	VM_VTEXTMIN	8
#define	VM_VNODEMIN	9
#define	VM_MAXSLP	10
#define	VM_USPACE	11
#define	VM_MALLOC_CONF	12		/* config for userland malloc */
#define	VM_MAXID	13		/* number of valid vm ids */

#define	CTL_VM_NAMES { \
	{ 0, 0 }, \
	{ "vmmeter", CTLTYPE_STRUCT }, \
	{ "loadavg", CTLTYPE_STRUCT }, \
	{ "psstrings", CTLTYPE_STRUCT }, \
	{ "uvmexp", CTLTYPE_STRUCT }, \
	{ "swapencrypt", CTLTYPE_NODE }, \
	{ "nkmempages", CTLTYPE_INT }, \
	{ "anonmin", CTLTYPE_INT }, \
	{ "vtextmin", CTLTYPE_INT }, \
	{ "vnodemin", CTLTYPE_INT }, \
	{ "maxslp", CTLTYPE_INT }, \
	{ "uspace", CTLTYPE_INT }, \
	{ "malloc_conf", CTLTYPE_STRING }, \
}

/*
 * uvmexp: global data structures that are exported to parts of the kernel
 * other than the vm system.
 *
 *  Locks used to protect struct members in this file:
 *	a	atomic operations
 *	I	immutable after creation
 *	K	kernel lock
 *	F	uvm_lock_fpageq
 *	L	uvm_lock_pageq
 *	S	uvm_swap_data_lock
 *	p	copy of per-CPU counters, used only by userland.
 */
struct uvmexp {
	/* vm_page constants */
	int pagesize;   /* size of a page (PAGE_SIZE): must be power of 2 */
	int pagemask;   /* page mask */
	int pageshift;  /* page shift */

	/* vm_page counters */
	int npages;     /* [I] number of pages we manage */
	int free;       /* [F] number of free pages */
	int active;     /* [L] # of active pages */
	int inactive;   /* [L] # of pages that we free'd but may want back */
	int paging;	/* number of pages in the process of being paged out */
	int wired;      /* number of wired pages */

	int zeropages;		/* [F] number of zero'd pages */
	int reserve_pagedaemon; /* [I] # of pages reserved for pagedaemon */
	int reserve_kernel;	/* [I] # of pages reserved for kernel */
	int percpucaches;	/* [a] # of pages in per-CPU caches */
	int vnodepages;		/* XXX # of pages used by vnode page cache */
	int vtextpages;		/* XXX # of pages used by vtext vnodes */

	/* pageout params */
	int freemin;    /* [I] min number of free pages */
	int freetarg;   /* [I] target number of free pages */
	int inactarg;   /* target number of inactive pages */
	int wiredmax;   /* [I] max number of wired pages */
	int anonmin;	/* min threshold for anon pages */
	int vtextmin;	/* min threshold for vtext pages */
	int vnodemin;	/* min threshold for vnode pages */
	int anonminpct;	/* min percent anon pages */
	int vtextminpct;/* min percent vtext pages */
	int vnodeminpct;/* min percent vnode pages */

	/* swap */
	int nswapdev;	/* [S] number of configured swap devices in system */
	int swpages;	/* [S] number of PAGE_SIZE'ed swap pages */
	int swpginuse;	/* [S] number of swap pages in use */
	int swpgonly;	/* [a] number of swap pages in use, not also in RAM */
	int nswget;	/* [a] number of swap pages moved from disk to RAM */
	int nanon;	/* XXX number total of anon's in system */
	int unused05;	/* formerly nanonneeded */
	int unused06;	/* formerly nfreeanon */

	/* stat counters */
	int faults;		/* [p] page fault count */
	int traps;		/* trap count */
	int intrs;		/* interrupt count */
	int swtch;		/* context switch count */
	int softs;		/* software interrupt count */
	int syscalls;		/* system calls */
	int pageins;		/* [p] pagein operation count */
				/* pageouts are in pdpageouts below */
	int pcphit;		/* [a] # of pagealloc from per-CPU cache */
	int pcpmiss;		/* [a] # of times a per-CPU cache was empty */
	int pgswapin;		/* pages swapped in */
	int pgswapout;		/* pages swapped out */
	int forks;  		/* forks */
	int forks_ppwait;	/* forks where parent waits */
	int forks_sharevm;	/* forks where vmspace is shared */
	int pga_zerohit;	/* pagealloc where zero wanted and zero
				   was available */
	int pga_zeromiss;	/* pagealloc where zero wanted and zero
				   not available */
	int unused09;		/* formerly zeroaborts */

	/* fault subcounters */
	int fltnoram;	/* [p] # of times fault was out of ram */
	int fltnoanon;	/* [p] # of times fault was out of anons */
	int fltnoamap;	/* [p] # of times fault was out of amap chunks */
	int fltpgwait;	/* [p] # of times fault had to wait on a page */
	int fltpgrele;	/* [p] # of times fault found a released page */
	int fltrelck;	/* [p] # of times fault relock called */
	int fltrelckok;	/* [p] # of times fault relock is a success */
	int fltanget;	/* [p] # of times fault gets anon page */
	int fltanretry;	/* [p] # of times fault retrys an anon get */
	int fltamcopy;	/* [p] # of times fault clears "needs copy" */
	int fltnamap;	/* [p] # of times fault maps a neighbor anon page */
	int fltnomap;	/* [p] # of times fault maps a neighbor obj page */
	int fltlget;	/* [p] # of times fault does a locked pgo_get */
	int fltget;	/* [p] # of times fault does an unlocked get */
	int flt_anon;	/* [p] # of times fault anon (case 1a) */
	int flt_acow;	/* [p] # of times fault anon cow (case 1b) */
	int flt_obj;	/* [p] # of times fault is on object page (2a) */
	int flt_prcopy;	/* [p] # of times fault promotes with copy (2b) */
	int flt_przero;	/* [p] # of times fault promotes with zerofill (2b) */

	/* daemon counters */
	int pdwoke;	/* [F] # of times daemon woke up */
	int pdrevs;	/* number of times daemon rev'd clock hand */
	int pdswout;	/* number of times daemon called for swapout */
	int pdfreed;	/* number of pages daemon freed since boot */
	int pdscans;	/* number of pages daemon scanned since boot */
	int pdanscan;	/* number of anonymous pages scanned by daemon */
	int pdobscan;	/* number of object pages scanned by daemon */
	int pdreact;	/* number of pages daemon reactivated since boot */
	int pdbusy;	/* number of times daemon found a busy page */
	int pdpageouts;	/* number of times daemon started a pageout */
	int pdpending;	/* number of times daemon got a pending pagout */
	int pddeact;	/* number of pages daemon deactivates */
	int unused11;	/* formerly pdreanon */
	int unused12;	/* formerly pdrevnode */
	int unused13;	/* formerly pdrevtext */

	int fpswtch;	/* FPU context switches */
	int kmapent;	/* number of kernel map entries */
};

struct _ps_strings {
	void	*val;
};

#ifdef _KERNEL

/*
 * Per-cpu UVM counters.
 */
extern struct cpumem *uvmexp_counters;

enum uvm_exp_counters {
	/* stat counters */
	faults,		/* page fault count */
	pageins,	/* pagein operation count */

	/* fault subcounters */
	flt_noram,	/* number of times fault was out of ram */
	flt_noanon,	/* number of times fault was out of anons */
	flt_noamap,	/* number of times fault was out of amap chunks */
	flt_pgwait,	/* number of times fault had to wait on a page */
	flt_pgrele,	/* number of times fault found a released page */
	flt_relck,	/* number of times fault relock called */
	flt_relckok,	/* number of times fault relock is a success */
	flt_anget,	/* number of times fault gets anon page */
	flt_anretry,	/* number of times fault retrys an anon get */
	flt_amcopy,	/* number of times fault clears "needs copy" */
	flt_namap,	/* number of times fault maps a neighbor anon page */
	flt_nomap,	/* number of times fault maps a neighbor obj page */
	flt_lget,	/* number of times fault does a locked pgo_get */
	flt_get,	/* number of times fault does an unlocked get */
	flt_anon,	/* number of times fault anon (case 1a) */
	flt_acow,	/* number of times fault anon cow (case 1b) */
	flt_obj,	/* number of times fault is on object page (2a) */
	flt_prcopy,	/* number of times fault promotes with copy (2b) */
	flt_przero,	/* number of times fault promotes with zerofill (2b) */

	exp_ncounters
};

#endif /* _KERNEL */
#endif /*_UVM_UVMEXP_ */