/* $NetBSD: subr_evcnt.c,v 1.13 2018/11/24 17:40:37 maxv Exp $ */ /* * Copyright (c) 1996, 2000 Christopher G. Demetriou * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the * NetBSD Project. See http://www.NetBSD.org/ for * information about NetBSD. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * --(license Id: LICENSE.proto,v 1.1 2000/06/13 21:40:26 cgd Exp )-- */ /* * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This software was developed by the Computer Systems Engineering group * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and * contributed to Berkeley. * * All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Lawrence Berkeley Laboratories. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp (LBL) * * @(#)subr_autoconf.c 8.3 (Berkeley) 5/17/94 */ #include __KERNEL_RCSID(0, "$NetBSD: subr_evcnt.c,v 1.13 2018/11/24 17:40:37 maxv Exp $"); #include #include #include #include #include #include /* list of all events */ struct evcntlist allevents = TAILQ_HEAD_INITIALIZER(allevents); static kmutex_t evcnt_lock __cacheline_aligned; static bool init_done; static uint32_t evcnt_generation; /* * We need a dummy object to stuff into the evcnt link set to * ensure that there always is at least one object in the set. */ static struct evcnt dummy_static_evcnt; __link_set_add_bss(evcnts, dummy_static_evcnt); /* * Initialize event counters. This does the attach procedure for * each of the static event counters in the "evcnts" link set. */ void evcnt_init(void) { __link_set_decl(evcnts, struct evcnt); struct evcnt * const *evp; KASSERT(!init_done); mutex_init(&evcnt_lock, MUTEX_DEFAULT, IPL_NONE); init_done = true; __link_set_foreach(evp, evcnts) { if (*evp == &dummy_static_evcnt) continue; evcnt_attach_static(*evp); } } /* * Attach a statically-initialized event. The type and string pointers * are already set up. */ void evcnt_attach_static(struct evcnt *ev) { int len; KASSERTMSG(init_done, "%s: evcnt non initialized: group=<%s> name=<%s>", __func__, ev->ev_group, ev->ev_name); len = strlen(ev->ev_group); #ifdef DIAGNOSTIC if (len == 0 || len >= EVCNT_STRING_MAX) /* ..._MAX includes NUL */ panic("evcnt_attach_static: group length (%s)", ev->ev_group); #endif ev->ev_grouplen = len; len = strlen(ev->ev_name); #ifdef DIAGNOSTIC if (len == 0 || len >= EVCNT_STRING_MAX) /* ..._MAX includes NUL */ panic("evcnt_attach_static: name length (%s)", ev->ev_name); #endif ev->ev_namelen = len; mutex_enter(&evcnt_lock); TAILQ_INSERT_TAIL(&allevents, ev, ev_list); mutex_exit(&evcnt_lock); } /* * Attach a dynamically-initialized event. Zero it, set up the type * and string pointers and then act like it was statically initialized. */ void evcnt_attach_dynamic_nozero(struct evcnt *ev, int type, const struct evcnt *parent, const char *group, const char *name) { ev->ev_type = type; ev->ev_parent = parent; ev->ev_group = group; ev->ev_name = name; evcnt_attach_static(ev); } /* * Attach a dynamically-initialized event. Zero it, set up the type * and string pointers and then act like it was statically initialized. */ void evcnt_attach_dynamic(struct evcnt *ev, int type, const struct evcnt *parent, const char *group, const char *name) { memset(ev, 0, sizeof *ev); evcnt_attach_dynamic_nozero(ev, type, parent, group, name); } /* * Detach an event. */ void evcnt_detach(struct evcnt *ev) { mutex_enter(&evcnt_lock); TAILQ_REMOVE(&allevents, ev, ev_list); evcnt_generation++; mutex_exit(&evcnt_lock); } struct xevcnt_sysctl { struct evcnt_sysctl evs; char ev_strings[2*EVCNT_STRING_MAX]; }; static size_t sysctl_fillevcnt(const struct evcnt *ev, struct xevcnt_sysctl *xevs, size_t *copylenp) { const bool allowaddr = get_expose_address(curproc); const size_t copylen = offsetof(struct evcnt_sysctl, ev_strings) + ev->ev_grouplen + 1 + ev->ev_namelen + 1; const size_t len = roundup2(copylen, sizeof(uint64_t)); if (xevs != NULL) { xevs->evs.ev_count = ev->ev_count; COND_SET_VALUE(xevs->evs.ev_addr, PTRTOUINT64(ev), allowaddr); COND_SET_VALUE(xevs->evs.ev_parent, PTRTOUINT64(ev->ev_parent), allowaddr); xevs->evs.ev_type = ev->ev_type; xevs->evs.ev_grouplen = ev->ev_grouplen; xevs->evs.ev_namelen = ev->ev_namelen; xevs->evs.ev_len = len / sizeof(uint64_t); strcpy(xevs->evs.ev_strings, ev->ev_group); strcpy(xevs->evs.ev_strings + ev->ev_grouplen + 1, ev->ev_name); } *copylenp = copylen; return len; } static int sysctl_doevcnt(SYSCTLFN_ARGS) { struct xevcnt_sysctl *xevs0 = NULL, *xevs; const struct evcnt *ev; int error; int retries; size_t needed, len; char *dp; if (namelen == 1 && name[0] == CTL_QUERY) return (sysctl_query(SYSCTLFN_CALL(rnode))); if (namelen != 2) return (EINVAL); /* * We can filter on the type of evcnt. */ const int filter = name[0]; if (filter != EVCNT_TYPE_ANY && filter != EVCNT_TYPE_MISC && filter != EVCNT_TYPE_INTR && filter != EVCNT_TYPE_TRAP) return (EINVAL); const u_int count = name[1]; if (count != KERN_EVCNT_COUNT_ANY && count != KERN_EVCNT_COUNT_NONZERO) return (EINVAL); sysctl_unlock(); if (oldp != NULL && xevs0 == NULL) xevs0 = kmem_zalloc(sizeof(*xevs0), KM_SLEEP); retries = 100; retry: dp = oldp; len = (oldp != NULL) ? *oldlenp : 0; xevs = xevs0; error = 0; needed = 0; mutex_enter(&evcnt_lock); TAILQ_FOREACH(ev, &allevents, ev_list) { if (filter != EVCNT_TYPE_ANY && filter != ev->ev_type) continue; if (count == KERN_EVCNT_COUNT_NONZERO && ev->ev_count == 0) continue; /* * Prepare to copy. If xevs is NULL, fillevcnt will just * how big the item is. */ size_t copylen; const size_t elem_size = sysctl_fillevcnt(ev, xevs, ©len); needed += elem_size; if (len < elem_size) { xevs = NULL; continue; } KASSERT(xevs != NULL); KASSERT(xevs->evs.ev_grouplen != 0); KASSERT(xevs->evs.ev_namelen != 0); KASSERT(xevs->evs.ev_strings[0] != 0); const uint32_t last_generation = evcnt_generation; mutex_exit(&evcnt_lock); /* * Only copy the actual number of bytes, not the rounded * number. If we did the latter we'd have to zero them * first or we'd leak random kernel memory. */ error = copyout(xevs, dp, copylen); mutex_enter(&evcnt_lock); if (error) break; if (__predict_false(last_generation != evcnt_generation)) { /* * This sysctl node is only for statistics. * Retry; if the queue keeps changing, then * bail out. */ if (--retries == 0) { error = EAGAIN; break; } mutex_exit(&evcnt_lock); goto retry; } /* * Now we deal with the pointer/len since we aren't going to * toss their values away. */ dp += elem_size; len -= elem_size; } mutex_exit(&evcnt_lock); if (xevs0 != NULL) kmem_free(xevs0, sizeof(*xevs0)); sysctl_relock(); *oldlenp = needed; if (oldp == NULL) *oldlenp += 1024; return (error); } SYSCTL_SETUP(sysctl_evcnt_setup, "sysctl kern.evcnt subtree setup") { sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_STRUCT, "evcnt", SYSCTL_DESCR("Kernel evcnt information"), sysctl_doevcnt, 0, NULL, 0, CTL_KERN, KERN_EVCNT, CTL_EOL); }