/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1987, 1991, 1993 * The Regents of the University of California. * Copyright (c) 2005-2009 Robert N. M. Watson * Copyright (c) 2008 Otto Moerbeek (mallocarray) * 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. 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. * * @(#)kern_malloc.c 8.3 (Berkeley) 1/4/94 */ /* * Kernel malloc(9) implementation -- general purpose kernel memory allocator * based on memory types. Back end is implemented using the UMA(9) zone * allocator. A set of fixed-size buckets are used for smaller allocations, * and a special UMA allocation interface is used for larger allocations. * Callers declare memory types, and statistics are maintained independently * for each memory type. Statistics are maintained per-CPU for performance * reasons. See malloc(9) and comments in malloc.h for a detailed * description. */ #include __FBSDID("$FreeBSD$"); #include "opt_ddb.h" #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef EPOCH_TRACE #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEBUG_MEMGUARD #include #endif #ifdef DEBUG_REDZONE #include #endif #if defined(INVARIANTS) && defined(__i386__) #include #endif #include #ifdef KDTRACE_HOOKS #include bool __read_frequently dtrace_malloc_enabled; dtrace_malloc_probe_func_t __read_mostly dtrace_malloc_probe; #endif #if defined(INVARIANTS) || defined(MALLOC_MAKE_FAILURES) || \ defined(DEBUG_MEMGUARD) || defined(DEBUG_REDZONE) #define MALLOC_DEBUG 1 #endif #ifdef DEBUG_REDZONE #define DEBUG_REDZONE_ARG_DEF , unsigned long osize #define DEBUG_REDZONE_ARG , osize #else #define DEBUG_REDZONE_ARG_DEF #define DEBUG_REDZONE_ARG #endif /* * When realloc() is called, if the new size is sufficiently smaller than * the old size, realloc() will allocate a new, smaller block to avoid * wasting memory. 'Sufficiently smaller' is defined as: newsize <= * oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'. */ #ifndef REALLOC_FRACTION #define REALLOC_FRACTION 1 /* new block if <= half the size */ #endif /* * Centrally define some common malloc types. */ MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches"); MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers"); static struct malloc_type *kmemstatistics; static int kmemcount; #define KMEM_ZSHIFT 4 #define KMEM_ZBASE 16 #define KMEM_ZMASK (KMEM_ZBASE - 1) #define KMEM_ZMAX 65536 #define KMEM_ZSIZE (KMEM_ZMAX >> KMEM_ZSHIFT) static uint8_t kmemsize[KMEM_ZSIZE + 1]; #ifndef MALLOC_DEBUG_MAXZONES #define MALLOC_DEBUG_MAXZONES 1 #endif static int numzones = MALLOC_DEBUG_MAXZONES; /* * Small malloc(9) memory allocations are allocated from a set of UMA buckets * of various sizes. * * Warning: the layout of the struct is duplicated in libmemstat for KVM support. * * XXX: The comment here used to read "These won't be powers of two for * long." It's possible that a significant amount of wasted memory could be * recovered by tuning the sizes of these buckets. */ struct { int kz_size; const char *kz_name; uma_zone_t kz_zone[MALLOC_DEBUG_MAXZONES]; } kmemzones[] = { {16, "malloc-16", }, {32, "malloc-32", }, {64, "malloc-64", }, {128, "malloc-128", }, {256, "malloc-256", }, {384, "malloc-384", }, {512, "malloc-512", }, {1024, "malloc-1024", }, {2048, "malloc-2048", }, {4096, "malloc-4096", }, {8192, "malloc-8192", }, {16384, "malloc-16384", }, {32768, "malloc-32768", }, {65536, "malloc-65536", }, {0, NULL}, }; u_long vm_kmem_size; SYSCTL_ULONG(_vm, OID_AUTO, kmem_size, CTLFLAG_RDTUN, &vm_kmem_size, 0, "Size of kernel memory"); static u_long kmem_zmax = KMEM_ZMAX; SYSCTL_ULONG(_vm, OID_AUTO, kmem_zmax, CTLFLAG_RDTUN, &kmem_zmax, 0, "Maximum allocation size that malloc(9) would use UMA as backend"); static u_long vm_kmem_size_min; SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_min, CTLFLAG_RDTUN, &vm_kmem_size_min, 0, "Minimum size of kernel memory"); static u_long vm_kmem_size_max; SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RDTUN, &vm_kmem_size_max, 0, "Maximum size of kernel memory"); static u_int vm_kmem_size_scale; SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RDTUN, &vm_kmem_size_scale, 0, "Scale factor for kernel memory size"); static int sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS); SYSCTL_PROC(_vm, OID_AUTO, kmem_map_size, CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, sysctl_kmem_map_size, "LU", "Current kmem allocation size"); static int sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS); SYSCTL_PROC(_vm, OID_AUTO, kmem_map_free, CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, sysctl_kmem_map_free, "LU", "Free space in kmem"); static SYSCTL_NODE(_vm, OID_AUTO, malloc, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "Malloc information"); static u_int vm_malloc_zone_count = nitems(kmemzones); SYSCTL_UINT(_vm_malloc, OID_AUTO, zone_count, CTLFLAG_RD, &vm_malloc_zone_count, 0, "Number of malloc zones"); static int sysctl_vm_malloc_zone_sizes(SYSCTL_HANDLER_ARGS); SYSCTL_PROC(_vm_malloc, OID_AUTO, zone_sizes, CTLFLAG_RD | CTLTYPE_OPAQUE | CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_malloc_zone_sizes, "S", "Zone sizes used by malloc"); /* * The malloc_mtx protects the kmemstatistics linked list. */ struct mtx malloc_mtx; static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS); #if defined(MALLOC_MAKE_FAILURES) || (MALLOC_DEBUG_MAXZONES > 1) static SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "Kernel malloc debugging options"); #endif /* * malloc(9) fault injection -- cause malloc failures every (n) mallocs when * the caller specifies M_NOWAIT. If set to 0, no failures are caused. */ #ifdef MALLOC_MAKE_FAILURES static int malloc_failure_rate; static int malloc_nowait_count; static int malloc_failure_count; SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RWTUN, &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail"); SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD, &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures"); #endif static int sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS) { u_long size; size = uma_size(); return (sysctl_handle_long(oidp, &size, 0, req)); } static int sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS) { u_long size, limit; /* The sysctl is unsigned, implement as a saturation value. */ size = uma_size(); limit = uma_limit(); if (size > limit) size = 0; else size = limit - size; return (sysctl_handle_long(oidp, &size, 0, req)); } static int sysctl_vm_malloc_zone_sizes(SYSCTL_HANDLER_ARGS) { int sizes[nitems(kmemzones)]; int i; for (i = 0; i < nitems(kmemzones); i++) { sizes[i] = kmemzones[i].kz_size; } return (SYSCTL_OUT(req, &sizes, sizeof(sizes))); } /* * malloc(9) uma zone separation -- sub-page buffer overruns in one * malloc type will affect only a subset of other malloc types. */ #if MALLOC_DEBUG_MAXZONES > 1 static void tunable_set_numzones(void) { TUNABLE_INT_FETCH("debug.malloc.numzones", &numzones); /* Sanity check the number of malloc uma zones. */ if (numzones <= 0) numzones = 1; if (numzones > MALLOC_DEBUG_MAXZONES) numzones = MALLOC_DEBUG_MAXZONES; } SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL); SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &numzones, 0, "Number of malloc uma subzones"); /* * Any number that changes regularly is an okay choice for the * offset. Build numbers are pretty good of you have them. */ static u_int zone_offset = __FreeBSD_version; TUNABLE_INT("debug.malloc.zone_offset", &zone_offset); SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN, &zone_offset, 0, "Separate malloc types by examining the " "Nth character in the malloc type short description."); static void mtp_set_subzone(struct malloc_type *mtp) { struct malloc_type_internal *mtip; const char *desc; size_t len; u_int val; mtip = &mtp->ks_mti; desc = mtp->ks_shortdesc; if (desc == NULL || (len = strlen(desc)) == 0) val = 0; else val = desc[zone_offset % len]; mtip->mti_zone = (val % numzones); } static inline u_int mtp_get_subzone(struct malloc_type *mtp) { struct malloc_type_internal *mtip; mtip = &mtp->ks_mti; KASSERT(mtip->mti_zone < numzones, ("mti_zone %u out of range %d", mtip->mti_zone, numzones)); return (mtip->mti_zone); } #elif MALLOC_DEBUG_MAXZONES == 0 #error "MALLOC_DEBUG_MAXZONES must be positive." #else static void mtp_set_subzone(struct malloc_type *mtp) { struct malloc_type_internal *mtip; mtip = &mtp->ks_mti; mtip->mti_zone = 0; } static inline u_int mtp_get_subzone(struct malloc_type *mtp) { return (0); } #endif /* MALLOC_DEBUG_MAXZONES > 1 */ /* * An allocation has succeeded -- update malloc type statistics for the * amount of bucket size. Occurs within a critical section so that the * thread isn't preempted and doesn't migrate while updating per-PCU * statistics. */ static void malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size, int zindx) { struct malloc_type_internal *mtip; struct malloc_type_stats *mtsp; critical_enter(); mtip = &mtp->ks_mti; mtsp = zpcpu_get(mtip->mti_stats); if (size > 0) { mtsp->mts_memalloced += size; mtsp->mts_numallocs++; } if (zindx != -1) mtsp->mts_size |= 1 << zindx; #ifdef KDTRACE_HOOKS if (__predict_false(dtrace_malloc_enabled)) { uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC]; if (probe_id != 0) (dtrace_malloc_probe)(probe_id, (uintptr_t) mtp, (uintptr_t) mtip, (uintptr_t) mtsp, size, zindx); } #endif critical_exit(); } void malloc_type_allocated(struct malloc_type *mtp, unsigned long size) { if (size > 0) malloc_type_zone_allocated(mtp, size, -1); } /* * A free operation has occurred -- update malloc type statistics for the * amount of the bucket size. Occurs within a critical section so that the * thread isn't preempted and doesn't migrate while updating per-CPU * statistics. */ void malloc_type_freed(struct malloc_type *mtp, unsigned long size) { struct malloc_type_internal *mtip; struct malloc_type_stats *mtsp; critical_enter(); mtip = &mtp->ks_mti; mtsp = zpcpu_get(mtip->mti_stats); mtsp->mts_memfreed += size; mtsp->mts_numfrees++; #ifdef KDTRACE_HOOKS if (__predict_false(dtrace_malloc_enabled)) { uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE]; if (probe_id != 0) (dtrace_malloc_probe)(probe_id, (uintptr_t) mtp, (uintptr_t) mtip, (uintptr_t) mtsp, size, 0); } #endif critical_exit(); } /* * contigmalloc: * * Allocate a block of physically contiguous memory. * * If M_NOWAIT is set, this routine will not block and return NULL if * the allocation fails. */ void * contigmalloc(unsigned long size, struct malloc_type *type, int flags, vm_paddr_t low, vm_paddr_t high, unsigned long alignment, vm_paddr_t boundary) { void *ret; ret = (void *)kmem_alloc_contig(size, flags, low, high, alignment, boundary, VM_MEMATTR_DEFAULT); if (ret != NULL) malloc_type_allocated(type, round_page(size)); return (ret); } void * contigmalloc_domainset(unsigned long size, struct malloc_type *type, struct domainset *ds, int flags, vm_paddr_t low, vm_paddr_t high, unsigned long alignment, vm_paddr_t boundary) { void *ret; ret = (void *)kmem_alloc_contig_domainset(ds, size, flags, low, high, alignment, boundary, VM_MEMATTR_DEFAULT); if (ret != NULL) malloc_type_allocated(type, round_page(size)); return (ret); } /* * contigfree: * * Free a block of memory allocated by contigmalloc. * * This routine may not block. */ void contigfree(void *addr, unsigned long size, struct malloc_type *type) { kmem_free((vm_offset_t)addr, size); malloc_type_freed(type, round_page(size)); } #ifdef MALLOC_DEBUG static int malloc_dbg(caddr_t *vap, size_t *sizep, struct malloc_type *mtp, int flags) { #ifdef INVARIANTS int indx; KASSERT(mtp->ks_version == M_VERSION, ("malloc: bad malloc type version")); /* * Check that exactly one of M_WAITOK or M_NOWAIT is specified. */ indx = flags & (M_WAITOK | M_NOWAIT); if (indx != M_NOWAIT && indx != M_WAITOK) { static struct timeval lasterr; static int curerr, once; if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) { printf("Bad malloc flags: %x\n", indx); kdb_backtrace(); flags |= M_WAITOK; once++; } } #endif #ifdef MALLOC_MAKE_FAILURES if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) { atomic_add_int(&malloc_nowait_count, 1); if ((malloc_nowait_count % malloc_failure_rate) == 0) { atomic_add_int(&malloc_failure_count, 1); *vap = NULL; return (EJUSTRETURN); } } #endif if (flags & M_WAITOK) { KASSERT(curthread->td_intr_nesting_level == 0, ("malloc(M_WAITOK) in interrupt context")); if (__predict_false(!THREAD_CAN_SLEEP())) { #ifdef EPOCH_TRACE epoch_trace_list(curthread); #endif KASSERT(1, ("malloc(M_WAITOK) with sleeping prohibited")); } } KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("malloc: called with spinlock or critical section held")); #ifdef DEBUG_MEMGUARD if (memguard_cmp_mtp(mtp, *sizep)) { *vap = memguard_alloc(*sizep, flags); if (*vap != NULL) return (EJUSTRETURN); /* This is unfortunate but should not be fatal. */ } #endif #ifdef DEBUG_REDZONE *sizep = redzone_size_ntor(*sizep); #endif return (0); } #endif /* * Handle large allocations and frees by using kmem_malloc directly. */ static inline bool malloc_large_slab(uma_slab_t slab) { uintptr_t va; va = (uintptr_t)slab; return ((va & 1) != 0); } static inline size_t malloc_large_size(uma_slab_t slab) { uintptr_t va; va = (uintptr_t)slab; return (va >> 1); } static caddr_t __noinline malloc_large(size_t *size, struct malloc_type *mtp, struct domainset *policy, int flags DEBUG_REDZONE_ARG_DEF) { vm_offset_t kva; caddr_t va; size_t sz; sz = roundup(*size, PAGE_SIZE); kva = kmem_malloc_domainset(policy, sz, flags); if (kva != 0) { /* The low bit is unused for slab pointers. */ vsetzoneslab(kva, NULL, (void *)((sz << 1) | 1)); uma_total_inc(sz); *size = sz; } va = (caddr_t)kva; malloc_type_allocated(mtp, va == NULL ? 0 : sz); if (__predict_false(va == NULL)) { KASSERT((flags & M_WAITOK) == 0, ("malloc(M_WAITOK) returned NULL")); } #ifdef DEBUG_REDZONE if (va != NULL) va = redzone_setup(va, osize); #endif return (va); } static void free_large(void *addr, size_t size) { kmem_free((vm_offset_t)addr, size); uma_total_dec(size); } /* * malloc: * * Allocate a block of memory. * * If M_NOWAIT is set, this routine will not block and return NULL if * the allocation fails. */ void * (malloc)(size_t size, struct malloc_type *mtp, int flags) { int indx; caddr_t va; uma_zone_t zone; #ifdef DEBUG_REDZONE unsigned long osize = size; #endif MPASS((flags & M_EXEC) == 0); #ifdef MALLOC_DEBUG va = NULL; if (malloc_dbg(&va, &size, mtp, flags) != 0) return (va); #endif if (__predict_false(size > kmem_zmax)) return (malloc_large(&size, mtp, DOMAINSET_RR(), flags DEBUG_REDZONE_ARG)); if (size & KMEM_ZMASK) size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; indx = kmemsize[size >> KMEM_ZSHIFT]; zone = kmemzones[indx].kz_zone[mtp_get_subzone(mtp)]; va = uma_zalloc(zone, flags); if (va != NULL) size = zone->uz_size; malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx); if (__predict_false(va == NULL)) { KASSERT((flags & M_WAITOK) == 0, ("malloc(M_WAITOK) returned NULL")); } #ifdef DEBUG_REDZONE if (va != NULL) va = redzone_setup(va, osize); #endif return ((void *) va); } static void * malloc_domain(size_t *sizep, int *indxp, struct malloc_type *mtp, int domain, int flags) { uma_zone_t zone; caddr_t va; size_t size; int indx; size = *sizep; KASSERT(size <= kmem_zmax && (flags & M_EXEC) == 0, ("malloc_domain: Called with bad flag / size combination.")); if (size & KMEM_ZMASK) size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; indx = kmemsize[size >> KMEM_ZSHIFT]; zone = kmemzones[indx].kz_zone[mtp_get_subzone(mtp)]; va = uma_zalloc_domain(zone, NULL, domain, flags); if (va != NULL) *sizep = zone->uz_size; *indxp = indx; return ((void *)va); } void * malloc_domainset(size_t size, struct malloc_type *mtp, struct domainset *ds, int flags) { struct vm_domainset_iter di; caddr_t va; int domain; int indx; #ifdef DEBUG_REDZONE unsigned long osize = size; #endif MPASS((flags & M_EXEC) == 0); #ifdef MALLOC_DEBUG va = NULL; if (malloc_dbg(&va, &size, mtp, flags) != 0) return (va); #endif if (__predict_false(size > kmem_zmax)) return (malloc_large(&size, mtp, DOMAINSET_RR(), flags DEBUG_REDZONE_ARG)); vm_domainset_iter_policy_init(&di, ds, &domain, &flags); do { va = malloc_domain(&size, &indx, mtp, domain, flags); } while (va == NULL && vm_domainset_iter_policy(&di, &domain) == 0); malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx); if (__predict_false(va == NULL)) { KASSERT((flags & M_WAITOK) == 0, ("malloc(M_WAITOK) returned NULL")); } #ifdef DEBUG_REDZONE if (va != NULL) va = redzone_setup(va, osize); #endif return (va); } /* * Allocate an executable area. */ void * malloc_exec(size_t size, struct malloc_type *mtp, int flags) { return (malloc_domainset_exec(size, mtp, DOMAINSET_RR(), flags)); } void * malloc_domainset_exec(size_t size, struct malloc_type *mtp, struct domainset *ds, int flags) { #ifdef DEBUG_REDZONE unsigned long osize = size; #endif #ifdef MALLOC_DEBUG caddr_t va; #endif flags |= M_EXEC; #ifdef MALLOC_DEBUG va = NULL; if (malloc_dbg(&va, &size, mtp, flags) != 0) return (va); #endif return (malloc_large(&size, mtp, ds, flags DEBUG_REDZONE_ARG)); } void * malloc_domainset_aligned(size_t size, size_t align, struct malloc_type *mtp, struct domainset *ds, int flags) { void *res; KASSERT(align != 0 && powerof2(align), ("malloc_domainset_aligned: wrong align %#zx size %#zx", align, size)); KASSERT(align <= kmemzones[nitems(kmemzones) - 2].kz_size, ("malloc_domainset_aligned: align %#zx (size %#zx) too large", align, size)); if (size < align) size = align; res = malloc_domainset(size, mtp, ds, flags); KASSERT(res == NULL || ((uintptr_t)res & (align - 1)) == 0, ("malloc_domainset_aligned: result not aligned %p size %#zx " "align %#zx", res, size, align)); return (res); } void * mallocarray(size_t nmemb, size_t size, struct malloc_type *type, int flags) { if (WOULD_OVERFLOW(nmemb, size)) panic("mallocarray: %zu * %zu overflowed", nmemb, size); return (malloc(size * nmemb, type, flags)); } #ifdef INVARIANTS static void free_save_type(void *addr, struct malloc_type *mtp, u_long size) { struct malloc_type **mtpp = addr; /* * Cache a pointer to the malloc_type that most recently freed * this memory here. This way we know who is most likely to * have stepped on it later. * * This code assumes that size is a multiple of 8 bytes for * 64 bit machines */ mtpp = (struct malloc_type **) ((unsigned long)mtpp & ~UMA_ALIGN_PTR); mtpp += (size - sizeof(struct malloc_type *)) / sizeof(struct malloc_type *); *mtpp = mtp; } #endif #ifdef MALLOC_DEBUG static int free_dbg(void **addrp, struct malloc_type *mtp) { void *addr; addr = *addrp; KASSERT(mtp->ks_version == M_VERSION, ("free: bad malloc type version")); KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("free: called with spinlock or critical section held")); /* free(NULL, ...) does nothing */ if (addr == NULL) return (EJUSTRETURN); #ifdef DEBUG_MEMGUARD if (is_memguard_addr(addr)) { memguard_free(addr); return (EJUSTRETURN); } #endif #ifdef DEBUG_REDZONE redzone_check(addr); *addrp = redzone_addr_ntor(addr); #endif return (0); } #endif /* * free: * * Free a block of memory allocated by malloc. * * This routine may not block. */ void free(void *addr, struct malloc_type *mtp) { uma_zone_t zone; uma_slab_t slab; u_long size; #ifdef MALLOC_DEBUG if (free_dbg(&addr, mtp) != 0) return; #endif /* free(NULL, ...) does nothing */ if (addr == NULL) return; vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab); if (slab == NULL) panic("free: address %p(%p) has not been allocated.\n", addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); if (__predict_true(!malloc_large_slab(slab))) { size = zone->uz_size; #ifdef INVARIANTS free_save_type(addr, mtp, size); #endif uma_zfree_arg(zone, addr, slab); } else { size = malloc_large_size(slab); free_large(addr, size); } malloc_type_freed(mtp, size); } /* * zfree: * * Zero then free a block of memory allocated by malloc. * * This routine may not block. */ void zfree(void *addr, struct malloc_type *mtp) { uma_zone_t zone; uma_slab_t slab; u_long size; #ifdef MALLOC_DEBUG if (free_dbg(&addr, mtp) != 0) return; #endif /* free(NULL, ...) does nothing */ if (addr == NULL) return; vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab); if (slab == NULL) panic("free: address %p(%p) has not been allocated.\n", addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); if (__predict_true(!malloc_large_slab(slab))) { size = zone->uz_size; #ifdef INVARIANTS free_save_type(addr, mtp, size); #endif explicit_bzero(addr, size); uma_zfree_arg(zone, addr, slab); } else { size = malloc_large_size(slab); explicit_bzero(addr, size); free_large(addr, size); } malloc_type_freed(mtp, size); } /* * realloc: change the size of a memory block */ void * realloc(void *addr, size_t size, struct malloc_type *mtp, int flags) { uma_zone_t zone; uma_slab_t slab; unsigned long alloc; void *newaddr; KASSERT(mtp->ks_version == M_VERSION, ("realloc: bad malloc type version")); KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), ("realloc: called with spinlock or critical section held")); /* realloc(NULL, ...) is equivalent to malloc(...) */ if (addr == NULL) return (malloc(size, mtp, flags)); /* * XXX: Should report free of old memory and alloc of new memory to * per-CPU stats. */ #ifdef DEBUG_MEMGUARD if (is_memguard_addr(addr)) return (memguard_realloc(addr, size, mtp, flags)); #endif #ifdef DEBUG_REDZONE slab = NULL; zone = NULL; alloc = redzone_get_size(addr); #else vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab); /* Sanity check */ KASSERT(slab != NULL, ("realloc: address %p out of range", (void *)addr)); /* Get the size of the original block */ if (!malloc_large_slab(slab)) alloc = zone->uz_size; else alloc = malloc_large_size(slab); /* Reuse the original block if appropriate */ if (size <= alloc && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE)) return (addr); #endif /* !DEBUG_REDZONE */ /* Allocate a new, bigger (or smaller) block */ if ((newaddr = malloc(size, mtp, flags)) == NULL) return (NULL); /* Copy over original contents */ bcopy(addr, newaddr, min(size, alloc)); free(addr, mtp); return (newaddr); } /* * reallocf: same as realloc() but free memory on failure. */ void * reallocf(void *addr, size_t size, struct malloc_type *mtp, int flags) { void *mem; if ((mem = realloc(addr, size, mtp, flags)) == NULL) free(addr, mtp); return (mem); } /* * malloc_size: returns the number of bytes allocated for a request of the * specified size */ size_t malloc_size(size_t size) { int indx; if (size > kmem_zmax) return (0); if (size & KMEM_ZMASK) size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; indx = kmemsize[size >> KMEM_ZSHIFT]; return (kmemzones[indx].kz_size); } /* * malloc_usable_size: returns the usable size of the allocation. */ size_t malloc_usable_size(const void *addr) { #ifndef DEBUG_REDZONE uma_zone_t zone; uma_slab_t slab; #endif u_long size; if (addr == NULL) return (0); #ifdef DEBUG_MEMGUARD if (is_memguard_addr(__DECONST(void *, addr))) return (memguard_get_req_size(addr)); #endif #ifdef DEBUG_REDZONE size = redzone_get_size(__DECONST(void *, addr)); #else vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab); if (slab == NULL) panic("malloc_usable_size: address %p(%p) is not allocated.\n", addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); if (!malloc_large_slab(slab)) size = zone->uz_size; else size = malloc_large_size(slab); #endif return (size); } CTASSERT(VM_KMEM_SIZE_SCALE >= 1); /* * Initialize the kernel memory (kmem) arena. */ void kmeminit(void) { u_long mem_size; u_long tmp; #ifdef VM_KMEM_SIZE if (vm_kmem_size == 0) vm_kmem_size = VM_KMEM_SIZE; #endif #ifdef VM_KMEM_SIZE_MIN if (vm_kmem_size_min == 0) vm_kmem_size_min = VM_KMEM_SIZE_MIN; #endif #ifdef VM_KMEM_SIZE_MAX if (vm_kmem_size_max == 0) vm_kmem_size_max = VM_KMEM_SIZE_MAX; #endif /* * Calculate the amount of kernel virtual address (KVA) space that is * preallocated to the kmem arena. In order to support a wide range * of machines, it is a function of the physical memory size, * specifically, * * min(max(physical memory size / VM_KMEM_SIZE_SCALE, * VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX) * * Every architecture must define an integral value for * VM_KMEM_SIZE_SCALE. However, the definitions of VM_KMEM_SIZE_MIN * and VM_KMEM_SIZE_MAX, which represent respectively the floor and * ceiling on this preallocation, are optional. Typically, * VM_KMEM_SIZE_MAX is itself a function of the available KVA space on * a given architecture. */ mem_size = vm_cnt.v_page_count; if (mem_size <= 32768) /* delphij XXX 128MB */ kmem_zmax = PAGE_SIZE; if (vm_kmem_size_scale < 1) vm_kmem_size_scale = VM_KMEM_SIZE_SCALE; /* * Check if we should use defaults for the "vm_kmem_size" * variable: */ if (vm_kmem_size == 0) { vm_kmem_size = mem_size / vm_kmem_size_scale; vm_kmem_size = vm_kmem_size * PAGE_SIZE < vm_kmem_size ? vm_kmem_size_max : vm_kmem_size * PAGE_SIZE; if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min) vm_kmem_size = vm_kmem_size_min; if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max) vm_kmem_size = vm_kmem_size_max; } if (vm_kmem_size == 0) panic("Tune VM_KMEM_SIZE_* for the platform"); /* * The amount of KVA space that is preallocated to the * kmem arena can be set statically at compile-time or manually * through the kernel environment. However, it is still limited to * twice the physical memory size, which has been sufficient to handle * the most severe cases of external fragmentation in the kmem arena. */ if (vm_kmem_size / 2 / PAGE_SIZE > mem_size) vm_kmem_size = 2 * mem_size * PAGE_SIZE; vm_kmem_size = round_page(vm_kmem_size); #ifdef DEBUG_MEMGUARD tmp = memguard_fudge(vm_kmem_size, kernel_map); #else tmp = vm_kmem_size; #endif uma_set_limit(tmp); #ifdef DEBUG_MEMGUARD /* * Initialize MemGuard if support compiled in. MemGuard is a * replacement allocator used for detecting tamper-after-free * scenarios as they occur. It is only used for debugging. */ memguard_init(kernel_arena); #endif } /* * Initialize the kernel memory allocator */ /* ARGSUSED*/ static void mallocinit(void *dummy) { int i; uint8_t indx; mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF); kmeminit(); if (kmem_zmax < PAGE_SIZE || kmem_zmax > KMEM_ZMAX) kmem_zmax = KMEM_ZMAX; for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) { int size = kmemzones[indx].kz_size; const char *name = kmemzones[indx].kz_name; size_t align; int subzone; align = UMA_ALIGN_PTR; if (powerof2(size) && size > sizeof(void *)) align = size - 1; for (subzone = 0; subzone < numzones; subzone++) { kmemzones[indx].kz_zone[subzone] = uma_zcreate(name, size, #ifdef INVARIANTS mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, #else NULL, NULL, NULL, NULL, #endif align, UMA_ZONE_MALLOC); } for (;i <= size; i+= KMEM_ZBASE) kmemsize[i >> KMEM_ZSHIFT] = indx; } } SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_SECOND, mallocinit, NULL); void malloc_init(void *data) { struct malloc_type_internal *mtip; struct malloc_type *mtp; KASSERT(vm_cnt.v_page_count != 0, ("malloc_register before vm_init")); mtp = data; if (mtp->ks_version != M_VERSION) panic("malloc_init: type %s with unsupported version %lu", mtp->ks_shortdesc, mtp->ks_version); mtip = &mtp->ks_mti; mtip->mti_stats = uma_zalloc_pcpu(pcpu_zone_64, M_WAITOK | M_ZERO); mtp_set_subzone(mtp); mtx_lock(&malloc_mtx); mtp->ks_next = kmemstatistics; kmemstatistics = mtp; kmemcount++; mtx_unlock(&malloc_mtx); } void malloc_uninit(void *data) { struct malloc_type_internal *mtip; struct malloc_type_stats *mtsp; struct malloc_type *mtp, *temp; long temp_allocs, temp_bytes; int i; mtp = data; KASSERT(mtp->ks_version == M_VERSION, ("malloc_uninit: bad malloc type version")); mtx_lock(&malloc_mtx); mtip = &mtp->ks_mti; if (mtp != kmemstatistics) { for (temp = kmemstatistics; temp != NULL; temp = temp->ks_next) { if (temp->ks_next == mtp) { temp->ks_next = mtp->ks_next; break; } } KASSERT(temp, ("malloc_uninit: type '%s' not found", mtp->ks_shortdesc)); } else kmemstatistics = mtp->ks_next; kmemcount--; mtx_unlock(&malloc_mtx); /* * Look for memory leaks. */ temp_allocs = temp_bytes = 0; for (i = 0; i <= mp_maxid; i++) { mtsp = zpcpu_get_cpu(mtip->mti_stats, i); temp_allocs += mtsp->mts_numallocs; temp_allocs -= mtsp->mts_numfrees; temp_bytes += mtsp->mts_memalloced; temp_bytes -= mtsp->mts_memfreed; } if (temp_allocs > 0 || temp_bytes > 0) { printf("Warning: memory type %s leaked memory on destroy " "(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc, temp_allocs, temp_bytes); } uma_zfree_pcpu(pcpu_zone_64, mtip->mti_stats); } struct malloc_type * malloc_desc2type(const char *desc) { struct malloc_type *mtp; mtx_assert(&malloc_mtx, MA_OWNED); for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { if (strcmp(mtp->ks_shortdesc, desc) == 0) return (mtp); } return (NULL); } static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS) { struct malloc_type_stream_header mtsh; struct malloc_type_internal *mtip; struct malloc_type_stats *mtsp, zeromts; struct malloc_type_header mth; struct malloc_type *mtp; int error, i; struct sbuf sbuf; error = sysctl_wire_old_buffer(req, 0); if (error != 0) return (error); sbuf_new_for_sysctl(&sbuf, NULL, 128, req); sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL); mtx_lock(&malloc_mtx); bzero(&zeromts, sizeof(zeromts)); /* * Insert stream header. */ bzero(&mtsh, sizeof(mtsh)); mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION; mtsh.mtsh_maxcpus = MAXCPU; mtsh.mtsh_count = kmemcount; (void)sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh)); /* * Insert alternating sequence of type headers and type statistics. */ for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { mtip = &mtp->ks_mti; /* * Insert type header. */ bzero(&mth, sizeof(mth)); strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME); (void)sbuf_bcat(&sbuf, &mth, sizeof(mth)); /* * Insert type statistics for each CPU. */ for (i = 0; i <= mp_maxid; i++) { mtsp = zpcpu_get_cpu(mtip->mti_stats, i); (void)sbuf_bcat(&sbuf, mtsp, sizeof(*mtsp)); } /* * Fill in the missing CPUs. */ for (; i < MAXCPU; i++) { (void)sbuf_bcat(&sbuf, &zeromts, sizeof(zeromts)); } } mtx_unlock(&malloc_mtx); error = sbuf_finish(&sbuf); sbuf_delete(&sbuf); return (error); } SYSCTL_PROC(_kern, OID_AUTO, malloc_stats, CTLFLAG_RD | CTLTYPE_STRUCT | CTLFLAG_MPSAFE, 0, 0, sysctl_kern_malloc_stats, "s,malloc_type_ustats", "Return malloc types"); SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0, "Count of kernel malloc types"); void malloc_type_list(malloc_type_list_func_t *func, void *arg) { struct malloc_type *mtp, **bufmtp; int count, i; size_t buflen; mtx_lock(&malloc_mtx); restart: mtx_assert(&malloc_mtx, MA_OWNED); count = kmemcount; mtx_unlock(&malloc_mtx); buflen = sizeof(struct malloc_type *) * count; bufmtp = malloc(buflen, M_TEMP, M_WAITOK); mtx_lock(&malloc_mtx); if (count < kmemcount) { free(bufmtp, M_TEMP); goto restart; } for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++) bufmtp[i] = mtp; mtx_unlock(&malloc_mtx); for (i = 0; i < count; i++) (func)(bufmtp[i], arg); free(bufmtp, M_TEMP); } #ifdef DDB static int64_t get_malloc_stats(const struct malloc_type_internal *mtip, uint64_t *allocs, uint64_t *inuse) { const struct malloc_type_stats *mtsp; uint64_t frees, alloced, freed; int i; *allocs = 0; frees = 0; alloced = 0; freed = 0; for (i = 0; i <= mp_maxid; i++) { mtsp = zpcpu_get_cpu(mtip->mti_stats, i); *allocs += mtsp->mts_numallocs; frees += mtsp->mts_numfrees; alloced += mtsp->mts_memalloced; freed += mtsp->mts_memfreed; } *inuse = *allocs - frees; return (alloced - freed); } DB_SHOW_COMMAND(malloc, db_show_malloc) { const char *fmt_hdr, *fmt_entry; struct malloc_type *mtp; uint64_t allocs, inuse; int64_t size; /* variables for sorting */ struct malloc_type *last_mtype, *cur_mtype; int64_t cur_size, last_size; int ties; if (modif[0] == 'i') { fmt_hdr = "%s,%s,%s,%s\n"; fmt_entry = "\"%s\",%ju,%jdK,%ju\n"; } else { fmt_hdr = "%18s %12s %12s %12s\n"; fmt_entry = "%18s %12ju %12jdK %12ju\n"; } db_printf(fmt_hdr, "Type", "InUse", "MemUse", "Requests"); /* Select sort, largest size first. */ last_mtype = NULL; last_size = INT64_MAX; for (;;) { cur_mtype = NULL; cur_size = -1; ties = 0; for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { /* * In the case of size ties, print out mtypes * in the order they are encountered. That is, * when we encounter the most recently output * mtype, we have already printed all preceding * ties, and we must print all following ties. */ if (mtp == last_mtype) { ties = 1; continue; } size = get_malloc_stats(&mtp->ks_mti, &allocs, &inuse); if (size > cur_size && size < last_size + ties) { cur_size = size; cur_mtype = mtp; } } if (cur_mtype == NULL) break; size = get_malloc_stats(&cur_mtype->ks_mti, &allocs, &inuse); db_printf(fmt_entry, cur_mtype->ks_shortdesc, inuse, howmany(size, 1024), allocs); if (db_pager_quit) break; last_mtype = cur_mtype; last_size = cur_size; } } #if MALLOC_DEBUG_MAXZONES > 1 DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches) { struct malloc_type_internal *mtip; struct malloc_type *mtp; u_int subzone; if (!have_addr) { db_printf("Usage: show multizone_matches \n"); return; } mtp = (void *)addr; if (mtp->ks_version != M_VERSION) { db_printf("Version %lx does not match expected %x\n", mtp->ks_version, M_VERSION); return; } mtip = &mtp->ks_mti; subzone = mtip->mti_zone; for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { mtip = &mtp->ks_mti; if (mtip->mti_zone != subzone) continue; db_printf("%s\n", mtp->ks_shortdesc); if (db_pager_quit) break; } } #endif /* MALLOC_DEBUG_MAXZONES > 1 */ #endif /* DDB */