diff options
Diffstat (limited to 'usr/src')
| -rw-r--r-- | usr/src/uts/common/os/clock.c | 6 | ||||
| -rw-r--r-- | usr/src/uts/common/os/vm_pageout.c | 84 | ||||
| -rw-r--r-- | usr/src/uts/common/vm/vm_page.c | 18 |
3 files changed, 94 insertions, 14 deletions
diff --git a/usr/src/uts/common/os/clock.c b/usr/src/uts/common/os/clock.c index 75c3b000db..93f12d7b96 100644 --- a/usr/src/uts/common/os/clock.c +++ b/usr/src/uts/common/os/clock.c @@ -318,7 +318,9 @@ time_t boot_time = 0; /* Boot time in seconds since 1970 */ cyclic_id_t clock_cyclic; /* clock()'s cyclic_id */ cyclic_id_t deadman_cyclic; /* deadman()'s cyclic_id */ -extern void clock_tick_schedule(int); +extern void clock_tick_schedule(int); +extern void set_freemem(void); +extern void pageout_deadman(void); static int lgrp_ticks; /* counter to schedule lgrp load calcs */ @@ -400,7 +402,6 @@ clock(void) uint_t w_io; cpu_t *cp; cpupart_t *cpupart; - extern void set_freemem(); void (*funcp)(); int32_t ltemp; int64_t lltemp; @@ -477,6 +478,7 @@ clock(void) if (one_sec) { loadavg_update(); deadman_counter++; + pageout_deadman(); } /* diff --git a/usr/src/uts/common/os/vm_pageout.c b/usr/src/uts/common/os/vm_pageout.c index 608208bbca..48e93d135a 100644 --- a/usr/src/uts/common/os/vm_pageout.c +++ b/usr/src/uts/common/os/vm_pageout.c @@ -18,13 +18,18 @@ * * CDDL HEADER END */ + +/* + * Copyright 2020 Oxide Computer Company + */ + /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ -/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ -/* All Rights Reserved */ +/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ +/* All Rights Reserved */ /* * University Copyright- Copyright (c) 1982, 1986, 1988 @@ -58,6 +63,7 @@ #include <sys/tnf_probe.h> #include <sys/mem_cage.h> #include <sys/time.h> +#include <sys/stdbool.h> #include <vm/hat.h> #include <vm/as.h> @@ -504,6 +510,23 @@ static struct async_reqs *push_list; /* pending reqs */ static kmutex_t push_lock; /* protects req pool */ static kcondvar_t push_cv; +/* + * If pageout() is stuck on a single push for this many seconds, + * pageout_deadman() will assume the system has hit a memory deadlock. If set + * to 0, the deadman will have no effect. + * + * Note that we are only looking for stalls in the calls that pageout() makes + * to VOP_PUTPAGE(). These calls are merely asynchronous requests for paging + * I/O, which should not take long unless the underlying strategy call blocks + * indefinitely for memory. The actual I/O request happens (or fails) later. + */ +uint_t pageout_deadman_seconds = 90; + +static uint_t pageout_stucktime = 0; +static bool pageout_pushing = false; +static uint64_t pageout_pushcount = 0; +static uint64_t pageout_pushcount_seen = 0; + static int async_list_size = 256; /* number of async request structs */ static void pageout_scanner(void); @@ -718,6 +741,7 @@ pageout() } push_list = arg->a_next; arg->a_next = NULL; + pageout_pushing = true; mutex_exit(&push_lock); if (VOP_PUTPAGE(arg->a_vp, (offset_t)arg->a_off, @@ -729,6 +753,8 @@ pageout() VN_RELE(arg->a_vp); mutex_enter(&push_lock); + pageout_pushing = false; + pageout_pushcount++; arg->a_next = req_freelist; /* back on freelist */ req_freelist = arg; push_list_size--; @@ -928,6 +954,58 @@ loop: } /* + * The pageout deadman is run once per second by clock(). + */ +void +pageout_deadman(void) +{ + if (panicstr != NULL) { + /* + * There is no pageout after panic. + */ + return; + } + + if (pageout_deadman_seconds == 0) { + /* + * The deadman is not enabled. + */ + return; + } + + if (!pageout_pushing) { + goto reset; + } + + /* + * We are pushing a page. Check to see if it is the same call we saw + * last time we looked: + */ + if (pageout_pushcount != pageout_pushcount_seen) { + /* + * It is a different call from the last check, so we are not + * stuck. + */ + goto reset; + } + + if (++pageout_stucktime >= pageout_deadman_seconds) { + panic("pageout_deadman: stuck pushing the same page for %d " + "seconds (freemem is %lu)", pageout_deadman_seconds, + freemem); + } + + return; + +reset: + /* + * Reset our tracking state to reflect that we are not stuck: + */ + pageout_stucktime = 0; + pageout_pushcount_seen = pageout_pushcount; +} + +/* * Look at the page at hand. If it is locked (e.g., for physical i/o), * system (u., page table) or free, then leave it alone. Otherwise, * if we are running the front hand, turn off the page's reference bit. @@ -950,7 +1028,7 @@ checkpage(struct page *pp, int whichhand) /* * Skip pages: - * - associated with the kernel vnode since + * - associated with the kernel vnode since * they are always "exclusively" locked. * - that are free * - that are shared more than po_share'd times diff --git a/usr/src/uts/common/vm/vm_page.c b/usr/src/uts/common/vm/vm_page.c index 0588d50a6c..bcc6d05d47 100644 --- a/usr/src/uts/common/vm/vm_page.c +++ b/usr/src/uts/common/vm/vm_page.c @@ -25,8 +25,8 @@ * Copyright 2018 Joyent, Inc. */ -/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */ -/* All Rights Reserved */ +/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */ +/* All Rights Reserved */ /* * University Copyright- Copyright (c) 1982, 1986, 1988 @@ -173,8 +173,8 @@ struct pcf { kmutex_t pcf_lock; /* protects the structure */ uint_t pcf_count; /* page count */ uint_t pcf_wait; /* number of waiters */ - uint_t pcf_block; /* pcgs flag to page_free() */ - uint_t pcf_reserve; /* pages freed after pcf_block set */ + uint_t pcf_block; /* pcgs flag to page_free() */ + uint_t pcf_reserve; /* pages freed after pcf_block set */ uint_t pcf_fill[10]; /* to line up on the caches */ }; @@ -1353,7 +1353,7 @@ wakeup_pcgs(void) * clock() on each TICK. */ void -set_freemem() +set_freemem(void) { struct pcf *p; ulong_t t; @@ -3920,8 +3920,8 @@ page_pp_unlock( /* * This routine reserves availrmem for npages; - * flags: KM_NOSLEEP or KM_SLEEP - * returns 1 on success or 0 on failure + * flags: KM_NOSLEEP or KM_SLEEP + * returns 1 on success or 0 on failure */ int page_resv(pgcnt_t npages, uint_t flags) @@ -3978,7 +3978,7 @@ void page_pp_useclaim( page_t *opp, /* original page frame losing lock */ page_t *npp, /* new page frame gaining lock */ - uint_t write_perm) /* set if vpage has PROT_WRITE */ + uint_t write_perm) /* set if vpage has PROT_WRITE */ { int payback = 0; int nidx, oidx; @@ -4732,7 +4732,7 @@ group_page_unlock(page_t *pp) /* * returns - * 0 : on success and *nrelocp is number of relocated PAGESIZE pages + * 0 : on success and *nrelocp is number of relocated PAGESIZE pages * ERANGE : this is not a base page * EBUSY : failure to get locks on the page/pages * ENOMEM : failure to obtain replacement pages |