diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/xfs/support/ktrace.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/xfs/support/ktrace.c')
-rw-r--r-- | fs/xfs/support/ktrace.c | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/fs/xfs/support/ktrace.c b/fs/xfs/support/ktrace.c new file mode 100644 index 00000000000..3dae14c8c55 --- /dev/null +++ b/fs/xfs/support/ktrace.c @@ -0,0 +1,346 @@ +/* + * Copyright (c) 2000-2003 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + * Further, this software is distributed without any warranty that it is + * free of the rightful claim of any third person regarding infringement + * or the like. Any license provided herein, whether implied or + * otherwise, applies only to this software file. Patent licenses, if + * any, provided herein do not apply to combinations of this program with + * other software, or any other product whatsoever. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write the Free Software Foundation, Inc., 59 + * Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, + * Mountain View, CA 94043, or: + * + * http://www.sgi.com + * + * For further information regarding this notice, see: + * + * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ + */ + +#include <xfs.h> + +static kmem_zone_t *ktrace_hdr_zone; +static kmem_zone_t *ktrace_ent_zone; +static int ktrace_zentries; + +void +ktrace_init(int zentries) +{ + ktrace_zentries = zentries; + + ktrace_hdr_zone = kmem_zone_init(sizeof(ktrace_t), + "ktrace_hdr"); + ASSERT(ktrace_hdr_zone); + + ktrace_ent_zone = kmem_zone_init(ktrace_zentries + * sizeof(ktrace_entry_t), + "ktrace_ent"); + ASSERT(ktrace_ent_zone); +} + +void +ktrace_uninit(void) +{ + kmem_cache_destroy(ktrace_hdr_zone); + kmem_cache_destroy(ktrace_ent_zone); +} + +/* + * ktrace_alloc() + * + * Allocate a ktrace header and enough buffering for the given + * number of entries. + */ +ktrace_t * +ktrace_alloc(int nentries, int sleep) +{ + ktrace_t *ktp; + ktrace_entry_t *ktep; + + ktp = (ktrace_t*)kmem_zone_alloc(ktrace_hdr_zone, sleep); + + if (ktp == (ktrace_t*)NULL) { + /* + * KM_SLEEP callers don't expect failure. + */ + if (sleep & KM_SLEEP) + panic("ktrace_alloc: NULL memory on KM_SLEEP request!"); + + return NULL; + } + + /* + * Special treatment for buffers with the ktrace_zentries entries + */ + if (nentries == ktrace_zentries) { + ktep = (ktrace_entry_t*)kmem_zone_zalloc(ktrace_ent_zone, + sleep); + } else { + ktep = (ktrace_entry_t*)kmem_zalloc((nentries * sizeof(*ktep)), + sleep); + } + + if (ktep == NULL) { + /* + * KM_SLEEP callers don't expect failure. + */ + if (sleep & KM_SLEEP) + panic("ktrace_alloc: NULL memory on KM_SLEEP request!"); + + kmem_free(ktp, sizeof(*ktp)); + + return NULL; + } + + spinlock_init(&(ktp->kt_lock), "kt_lock"); + + ktp->kt_entries = ktep; + ktp->kt_nentries = nentries; + ktp->kt_index = 0; + ktp->kt_rollover = 0; + return ktp; +} + + +/* + * ktrace_free() + * + * Free up the ktrace header and buffer. It is up to the caller + * to ensure that no-one is referencing it. + */ +void +ktrace_free(ktrace_t *ktp) +{ + int entries_size; + + if (ktp == (ktrace_t *)NULL) + return; + + spinlock_destroy(&ktp->kt_lock); + + /* + * Special treatment for the Vnode trace buffer. + */ + if (ktp->kt_nentries == ktrace_zentries) { + kmem_zone_free(ktrace_ent_zone, ktp->kt_entries); + } else { + entries_size = (int)(ktp->kt_nentries * sizeof(ktrace_entry_t)); + + kmem_free(ktp->kt_entries, entries_size); + } + + kmem_zone_free(ktrace_hdr_zone, ktp); +} + + +/* + * Enter the given values into the "next" entry in the trace buffer. + * kt_index is always the index of the next entry to be filled. + */ +void +ktrace_enter( + ktrace_t *ktp, + void *val0, + void *val1, + void *val2, + void *val3, + void *val4, + void *val5, + void *val6, + void *val7, + void *val8, + void *val9, + void *val10, + void *val11, + void *val12, + void *val13, + void *val14, + void *val15) +{ + static lock_t wrap_lock = SPIN_LOCK_UNLOCKED; + unsigned long flags; + int index; + ktrace_entry_t *ktep; + + ASSERT(ktp != NULL); + + /* + * Grab an entry by pushing the index up to the next one. + */ + spin_lock_irqsave(&wrap_lock, flags); + index = ktp->kt_index; + if (++ktp->kt_index == ktp->kt_nentries) + ktp->kt_index = 0; + spin_unlock_irqrestore(&wrap_lock, flags); + + if (!ktp->kt_rollover && index == ktp->kt_nentries - 1) + ktp->kt_rollover = 1; + + ASSERT((index >= 0) && (index < ktp->kt_nentries)); + + ktep = &(ktp->kt_entries[index]); + + ktep->val[0] = val0; + ktep->val[1] = val1; + ktep->val[2] = val2; + ktep->val[3] = val3; + ktep->val[4] = val4; + ktep->val[5] = val5; + ktep->val[6] = val6; + ktep->val[7] = val7; + ktep->val[8] = val8; + ktep->val[9] = val9; + ktep->val[10] = val10; + ktep->val[11] = val11; + ktep->val[12] = val12; + ktep->val[13] = val13; + ktep->val[14] = val14; + ktep->val[15] = val15; +} + +/* + * Return the number of entries in the trace buffer. + */ +int +ktrace_nentries( + ktrace_t *ktp) +{ + if (ktp == NULL) { + return 0; + } + + return (ktp->kt_rollover ? ktp->kt_nentries : ktp->kt_index); +} + +/* + * ktrace_first() + * + * This is used to find the start of the trace buffer. + * In conjunction with ktrace_next() it can be used to + * iterate through the entire trace buffer. This code does + * not do any locking because it is assumed that it is called + * from the debugger. + * + * The caller must pass in a pointer to a ktrace_snap + * structure in which we will keep some state used to + * iterate through the buffer. This state must not touched + * by any code outside of this module. + */ +ktrace_entry_t * +ktrace_first(ktrace_t *ktp, ktrace_snap_t *ktsp) +{ + ktrace_entry_t *ktep; + int index; + int nentries; + + if (ktp->kt_rollover) + index = ktp->kt_index; + else + index = 0; + + ktsp->ks_start = index; + ktep = &(ktp->kt_entries[index]); + + nentries = ktrace_nentries(ktp); + index++; + if (index < nentries) { + ktsp->ks_index = index; + } else { + ktsp->ks_index = 0; + if (index > nentries) + ktep = NULL; + } + return ktep; +} + +/* + * ktrace_next() + * + * This is used to iterate through the entries of the given + * trace buffer. The caller must pass in the ktrace_snap_t + * structure initialized by ktrace_first(). The return value + * will be either a pointer to the next ktrace_entry or NULL + * if all of the entries have been traversed. + */ +ktrace_entry_t * +ktrace_next( + ktrace_t *ktp, + ktrace_snap_t *ktsp) +{ + int index; + ktrace_entry_t *ktep; + + index = ktsp->ks_index; + if (index == ktsp->ks_start) { + ktep = NULL; + } else { + ktep = &ktp->kt_entries[index]; + } + + index++; + if (index == ktrace_nentries(ktp)) { + ktsp->ks_index = 0; + } else { + ktsp->ks_index = index; + } + + return ktep; +} + +/* + * ktrace_skip() + * + * Skip the next "count" entries and return the entry after that. + * Return NULL if this causes us to iterate past the beginning again. + */ +ktrace_entry_t * +ktrace_skip( + ktrace_t *ktp, + int count, + ktrace_snap_t *ktsp) +{ + int index; + int new_index; + ktrace_entry_t *ktep; + int nentries = ktrace_nentries(ktp); + + index = ktsp->ks_index; + new_index = index + count; + while (new_index >= nentries) { + new_index -= nentries; + } + if (index == ktsp->ks_start) { + /* + * We've iterated around to the start, so we're done. + */ + ktep = NULL; + } else if ((new_index < index) && (index < ktsp->ks_index)) { + /* + * We've skipped past the start again, so we're done. + */ + ktep = NULL; + ktsp->ks_index = ktsp->ks_start; + } else { + ktep = &(ktp->kt_entries[new_index]); + new_index++; + if (new_index == nentries) { + ktsp->ks_index = 0; + } else { + ktsp->ks_index = new_index; + } + } + return ktep; +} |