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authorIngo Molnar <mingo@kernel.org>2012-08-21 11:27:00 +0200
committerIngo Molnar <mingo@kernel.org>2012-08-21 11:27:00 +0200
commitbcada3d4b8c96b8792c2306f363992ca5ab9da42 (patch)
treee420679a5db6ea4e1694eef57f9abb6acac8d4d3 /fs/xfs/xfs_ialloc.c
parent26198c21d1b286a084fe5d514a30bc7e6c712a34 (diff)
parent000078bc3ee69efb1124b8478c7527389a826074 (diff)
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: * Fix include order for bison/flex-generated C files, from Ben Hutchings * Build fixes and documentation corrections from David Ahern * Group parsing support, from Jiri Olsa * UI/gtk refactorings and improvements from Namhyung Kim * NULL deref fix for perf script, from Namhyung Kim * Assorted cleanups from Robert Richter * Let O= makes handle relative paths, from Steven Rostedt * perf script python fixes, from Feng Tang. * Improve 'perf lock' error message when the needed tracepoints are not present, from David Ahern. * Initial bash completion support, from Frederic Weisbecker * Allow building without libelf, from Namhyung Kim. * Support DWARF CFI based unwind to have callchains when %bp based unwinding is not possible, from Jiri Olsa. * Symbol resolution fixes, while fixing support PPC64 files with an .opt ELF section was the end goal, several fixes for code that handles all architectures and cleanups are included, from Cody Schafer. * Add a description for the JIT interface, from Andi Kleen. * Assorted fixes for Documentation and build in 32 bit, from Robert Richter * Add support for non-tracepoint events in perf script python, from Feng Tang * Cache the libtraceevent event_format associated to each evsel early, so that we avoid relookups, i.e. calling pevent_find_event repeatedly when processing tracepoint events. [ This is to reduce the surface contact with libtraceevents and make clear what is that the perf tools needs from that lib: so far parsing the common and per event fields. ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'fs/xfs/xfs_ialloc.c')
-rw-r--r--fs/xfs/xfs_ialloc.c446
1 files changed, 222 insertions, 224 deletions
diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c
index 177a21a7ac4..21e37b55f7e 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -442,14 +442,13 @@ xfs_ialloc_next_ag(
* Select an allocation group to look for a free inode in, based on the parent
* inode and then mode. Return the allocation group buffer.
*/
-STATIC xfs_buf_t * /* allocation group buffer */
+STATIC xfs_agnumber_t
xfs_ialloc_ag_select(
xfs_trans_t *tp, /* transaction pointer */
xfs_ino_t parent, /* parent directory inode number */
umode_t mode, /* bits set to indicate file type */
int okalloc) /* ok to allocate more space */
{
- xfs_buf_t *agbp; /* allocation group header buffer */
xfs_agnumber_t agcount; /* number of ag's in the filesystem */
xfs_agnumber_t agno; /* current ag number */
int flags; /* alloc buffer locking flags */
@@ -459,6 +458,7 @@ xfs_ialloc_ag_select(
int needspace; /* file mode implies space allocated */
xfs_perag_t *pag; /* per allocation group data */
xfs_agnumber_t pagno; /* parent (starting) ag number */
+ int error;
/*
* Files of these types need at least one block if length > 0
@@ -474,7 +474,9 @@ xfs_ialloc_ag_select(
if (pagno >= agcount)
pagno = 0;
}
+
ASSERT(pagno < agcount);
+
/*
* Loop through allocation groups, looking for one with a little
* free space in it. Note we don't look for free inodes, exactly.
@@ -486,51 +488,45 @@ xfs_ialloc_ag_select(
flags = XFS_ALLOC_FLAG_TRYLOCK;
for (;;) {
pag = xfs_perag_get(mp, agno);
+ if (!pag->pagi_inodeok) {
+ xfs_ialloc_next_ag(mp);
+ goto nextag;
+ }
+
if (!pag->pagi_init) {
- if (xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
- agbp = NULL;
+ error = xfs_ialloc_pagi_init(mp, tp, agno);
+ if (error)
goto nextag;
- }
- } else
- agbp = NULL;
+ }
- if (!pag->pagi_inodeok) {
- xfs_ialloc_next_ag(mp);
- goto unlock_nextag;
+ if (pag->pagi_freecount) {
+ xfs_perag_put(pag);
+ return agno;
}
- /*
- * Is there enough free space for the file plus a block
- * of inodes (if we need to allocate some)?
- */
- ineed = pag->pagi_freecount ? 0 : XFS_IALLOC_BLOCKS(mp);
- if (ineed && !pag->pagf_init) {
- if (agbp == NULL &&
- xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
- agbp = NULL;
+ if (!okalloc)
+ goto nextag;
+
+ if (!pag->pagf_init) {
+ error = xfs_alloc_pagf_init(mp, tp, agno, flags);
+ if (error)
goto nextag;
- }
- (void)xfs_alloc_pagf_init(mp, tp, agno, flags);
}
- if (!ineed || pag->pagf_init) {
- if (ineed && !(longest = pag->pagf_longest))
- longest = pag->pagf_flcount > 0;
- if (!ineed ||
- (pag->pagf_freeblks >= needspace + ineed &&
- longest >= ineed &&
- okalloc)) {
- if (agbp == NULL &&
- xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
- agbp = NULL;
- goto nextag;
- }
- xfs_perag_put(pag);
- return agbp;
- }
+
+ /*
+ * Is there enough free space for the file plus a block of
+ * inodes? (if we need to allocate some)?
+ */
+ ineed = XFS_IALLOC_BLOCKS(mp);
+ longest = pag->pagf_longest;
+ if (!longest)
+ longest = pag->pagf_flcount > 0;
+
+ if (pag->pagf_freeblks >= needspace + ineed &&
+ longest >= ineed) {
+ xfs_perag_put(pag);
+ return agno;
}
-unlock_nextag:
- if (agbp)
- xfs_trans_brelse(tp, agbp);
nextag:
xfs_perag_put(pag);
/*
@@ -538,13 +534,13 @@ nextag:
* down.
*/
if (XFS_FORCED_SHUTDOWN(mp))
- return NULL;
+ return NULLAGNUMBER;
agno++;
if (agno >= agcount)
agno = 0;
if (agno == pagno) {
if (flags == 0)
- return NULL;
+ return NULLAGNUMBER;
flags = 0;
}
}
@@ -607,195 +603,39 @@ xfs_ialloc_get_rec(
}
/*
- * Visible inode allocation functions.
- */
-/*
- * Find a free (set) bit in the inode bitmask.
- */
-static inline int xfs_ialloc_find_free(xfs_inofree_t *fp)
-{
- return xfs_lowbit64(*fp);
-}
-
-/*
- * Allocate an inode on disk.
- * Mode is used to tell whether the new inode will need space, and whether
- * it is a directory.
- *
- * The arguments IO_agbp and alloc_done are defined to work within
- * the constraint of one allocation per transaction.
- * xfs_dialloc() is designed to be called twice if it has to do an
- * allocation to make more free inodes. On the first call,
- * IO_agbp should be set to NULL. If an inode is available,
- * i.e., xfs_dialloc() did not need to do an allocation, an inode
- * number is returned. In this case, IO_agbp would be set to the
- * current ag_buf and alloc_done set to false.
- * If an allocation needed to be done, xfs_dialloc would return
- * the current ag_buf in IO_agbp and set alloc_done to true.
- * The caller should then commit the current transaction, allocate a new
- * transaction, and call xfs_dialloc() again, passing in the previous
- * value of IO_agbp. IO_agbp should be held across the transactions.
- * Since the agbp is locked across the two calls, the second call is
- * guaranteed to have a free inode available.
+ * Allocate an inode.
*
- * Once we successfully pick an inode its number is returned and the
- * on-disk data structures are updated. The inode itself is not read
- * in, since doing so would break ordering constraints with xfs_reclaim.
+ * The caller selected an AG for us, and made sure that free inodes are
+ * available.
*/
-int
-xfs_dialloc(
- xfs_trans_t *tp, /* transaction pointer */
- xfs_ino_t parent, /* parent inode (directory) */
- umode_t mode, /* mode bits for new inode */
- int okalloc, /* ok to allocate more space */
- xfs_buf_t **IO_agbp, /* in/out ag header's buffer */
- boolean_t *alloc_done, /* true if we needed to replenish
- inode freelist */
- xfs_ino_t *inop) /* inode number allocated */
+STATIC int
+xfs_dialloc_ag(
+ struct xfs_trans *tp,
+ struct xfs_buf *agbp,
+ xfs_ino_t parent,
+ xfs_ino_t *inop)
{
- xfs_agnumber_t agcount; /* number of allocation groups */
- xfs_buf_t *agbp; /* allocation group header's buffer */
- xfs_agnumber_t agno; /* allocation group number */
- xfs_agi_t *agi; /* allocation group header structure */
- xfs_btree_cur_t *cur; /* inode allocation btree cursor */
- int error; /* error return value */
- int i; /* result code */
- int ialloced; /* inode allocation status */
- int noroom = 0; /* no space for inode blk allocation */
- xfs_ino_t ino; /* fs-relative inode to be returned */
- /* REFERENCED */
- int j; /* result code */
- xfs_mount_t *mp; /* file system mount structure */
- int offset; /* index of inode in chunk */
- xfs_agino_t pagino; /* parent's AG relative inode # */
- xfs_agnumber_t pagno; /* parent's AG number */
- xfs_inobt_rec_incore_t rec; /* inode allocation record */
- xfs_agnumber_t tagno; /* testing allocation group number */
- xfs_btree_cur_t *tcur; /* temp cursor */
- xfs_inobt_rec_incore_t trec; /* temp inode allocation record */
- struct xfs_perag *pag;
-
-
- if (*IO_agbp == NULL) {
- /*
- * We do not have an agbp, so select an initial allocation
- * group for inode allocation.
- */
- agbp = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
- /*
- * Couldn't find an allocation group satisfying the
- * criteria, give up.
- */
- if (!agbp) {
- *inop = NULLFSINO;
- return 0;
- }
- agi = XFS_BUF_TO_AGI(agbp);
- ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
- } else {
- /*
- * Continue where we left off before. In this case, we
- * know that the allocation group has free inodes.
- */
- agbp = *IO_agbp;
- agi = XFS_BUF_TO_AGI(agbp);
- ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
- ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
- }
- mp = tp->t_mountp;
- agcount = mp->m_sb.sb_agcount;
- agno = be32_to_cpu(agi->agi_seqno);
- tagno = agno;
- pagno = XFS_INO_TO_AGNO(mp, parent);
- pagino = XFS_INO_TO_AGINO(mp, parent);
-
- /*
- * If we have already hit the ceiling of inode blocks then clear
- * okalloc so we scan all available agi structures for a free
- * inode.
- */
-
- if (mp->m_maxicount &&
- mp->m_sb.sb_icount + XFS_IALLOC_INODES(mp) > mp->m_maxicount) {
- noroom = 1;
- okalloc = 0;
- }
+ struct xfs_mount *mp = tp->t_mountp;
+ struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
+ xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
+ xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent);
+ xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent);
+ struct xfs_perag *pag;
+ struct xfs_btree_cur *cur, *tcur;
+ struct xfs_inobt_rec_incore rec, trec;
+ xfs_ino_t ino;
+ int error;
+ int offset;
+ int i, j;
- /*
- * Loop until we find an allocation group that either has free inodes
- * or in which we can allocate some inodes. Iterate through the
- * allocation groups upward, wrapping at the end.
- */
- *alloc_done = B_FALSE;
- while (!agi->agi_freecount) {
- /*
- * Don't do anything if we're not supposed to allocate
- * any blocks, just go on to the next ag.
- */
- if (okalloc) {
- /*
- * Try to allocate some new inodes in the allocation
- * group.
- */
- if ((error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced))) {
- xfs_trans_brelse(tp, agbp);
- if (error == ENOSPC) {
- *inop = NULLFSINO;
- return 0;
- } else
- return error;
- }
- if (ialloced) {
- /*
- * We successfully allocated some inodes, return
- * the current context to the caller so that it
- * can commit the current transaction and call
- * us again where we left off.
- */
- ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
- *alloc_done = B_TRUE;
- *IO_agbp = agbp;
- *inop = NULLFSINO;
- return 0;
- }
- }
- /*
- * If it failed, give up on this ag.
- */
- xfs_trans_brelse(tp, agbp);
- /*
- * Go on to the next ag: get its ag header.
- */
-nextag:
- if (++tagno == agcount)
- tagno = 0;
- if (tagno == agno) {
- *inop = NULLFSINO;
- return noroom ? ENOSPC : 0;
- }
- pag = xfs_perag_get(mp, tagno);
- if (pag->pagi_inodeok == 0) {
- xfs_perag_put(pag);
- goto nextag;
- }
- error = xfs_ialloc_read_agi(mp, tp, tagno, &agbp);
- xfs_perag_put(pag);
- if (error)
- goto nextag;
- agi = XFS_BUF_TO_AGI(agbp);
- ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
- }
- /*
- * Here with an allocation group that has a free inode.
- * Reset agno since we may have chosen a new ag in the
- * loop above.
- */
- agno = tagno;
- *IO_agbp = NULL;
pag = xfs_perag_get(mp, agno);
+ ASSERT(pag->pagi_init);
+ ASSERT(pag->pagi_inodeok);
+ ASSERT(pag->pagi_freecount > 0);
+
restart_pagno:
- cur = xfs_inobt_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno));
+ cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
/*
* If pagino is 0 (this is the root inode allocation) use newino.
* This must work because we've just allocated some.
@@ -995,7 +835,7 @@ newino:
}
alloc_inode:
- offset = xfs_ialloc_find_free(&rec.ir_free);
+ offset = xfs_lowbit64(rec.ir_free);
ASSERT(offset >= 0);
ASSERT(offset < XFS_INODES_PER_CHUNK);
ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
@@ -1028,6 +868,164 @@ error0:
}
/*
+ * Allocate an inode on disk.
+ *
+ * Mode is used to tell whether the new inode will need space, and whether it
+ * is a directory.
+ *
+ * This function is designed to be called twice if it has to do an allocation
+ * to make more free inodes. On the first call, *IO_agbp should be set to NULL.
+ * If an inode is available without having to performn an allocation, an inode
+ * number is returned. In this case, *IO_agbp would be NULL. If an allocation
+ * needes to be done, xfs_dialloc would return the current AGI buffer in
+ * *IO_agbp. The caller should then commit the current transaction, allocate a
+ * new transaction, and call xfs_dialloc() again, passing in the previous value
+ * of *IO_agbp. IO_agbp should be held across the transactions. Since the AGI
+ * buffer is locked across the two calls, the second call is guaranteed to have
+ * a free inode available.
+ *
+ * Once we successfully pick an inode its number is returned and the on-disk
+ * data structures are updated. The inode itself is not read in, since doing so
+ * would break ordering constraints with xfs_reclaim.
+ */
+int
+xfs_dialloc(
+ struct xfs_trans *tp,
+ xfs_ino_t parent,
+ umode_t mode,
+ int okalloc,
+ struct xfs_buf **IO_agbp,
+ xfs_ino_t *inop)
+{
+ struct xfs_mount *mp = tp->t_mountp;
+ struct xfs_buf *agbp;
+ xfs_agnumber_t agno;
+ int error;
+ int ialloced;
+ int noroom = 0;
+ xfs_agnumber_t start_agno;
+ struct xfs_perag *pag;
+
+ if (*IO_agbp) {
+ /*
+ * If the caller passes in a pointer to the AGI buffer,
+ * continue where we left off before. In this case, we
+ * know that the allocation group has free inodes.
+ */
+ agbp = *IO_agbp;
+ goto out_alloc;
+ }
+
+ /*
+ * We do not have an agbp, so select an initial allocation
+ * group for inode allocation.
+ */
+ start_agno = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
+ if (start_agno == NULLAGNUMBER) {
+ *inop = NULLFSINO;
+ return 0;
+ }
+
+ /*
+ * If we have already hit the ceiling of inode blocks then clear
+ * okalloc so we scan all available agi structures for a free
+ * inode.
+ */
+ if (mp->m_maxicount &&
+ mp->m_sb.sb_icount + XFS_IALLOC_INODES(mp) > mp->m_maxicount) {
+ noroom = 1;
+ okalloc = 0;
+ }
+
+ /*
+ * Loop until we find an allocation group that either has free inodes
+ * or in which we can allocate some inodes. Iterate through the
+ * allocation groups upward, wrapping at the end.
+ */
+ agno = start_agno;
+ for (;;) {
+ pag = xfs_perag_get(mp, agno);
+ if (!pag->pagi_inodeok) {
+ xfs_ialloc_next_ag(mp);
+ goto nextag;
+ }
+
+ if (!pag->pagi_init) {
+ error = xfs_ialloc_pagi_init(mp, tp, agno);
+ if (error)
+ goto out_error;
+ }
+
+ /*
+ * Do a first racy fast path check if this AG is usable.
+ */
+ if (!pag->pagi_freecount && !okalloc)
+ goto nextag;
+
+ error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
+ if (error)
+ goto out_error;
+
+ /*
+ * Once the AGI has been read in we have to recheck
+ * pagi_freecount with the AGI buffer lock held.
+ */
+ if (pag->pagi_freecount) {
+ xfs_perag_put(pag);
+ goto out_alloc;
+ }
+
+ if (!okalloc) {
+ xfs_trans_brelse(tp, agbp);
+ goto nextag;
+ }
+
+ error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced);
+ if (error) {
+ xfs_trans_brelse(tp, agbp);
+
+ if (error != ENOSPC)
+ goto out_error;
+
+ xfs_perag_put(pag);
+ *inop = NULLFSINO;
+ return 0;
+ }
+
+ if (ialloced) {
+ /*
+ * We successfully allocated some inodes, return
+ * the current context to the caller so that it
+ * can commit the current transaction and call
+ * us again where we left off.
+ */
+ ASSERT(pag->pagi_freecount > 0);
+ xfs_perag_put(pag);
+
+ *IO_agbp = agbp;
+ *inop = NULLFSINO;
+ return 0;
+ }
+
+nextag:
+ xfs_perag_put(pag);
+ if (++agno == mp->m_sb.sb_agcount)
+ agno = 0;
+ if (agno == start_agno) {
+ *inop = NULLFSINO;
+ return noroom ? ENOSPC : 0;
+ }
+ }
+
+out_alloc:
+ *IO_agbp = NULL;
+ return xfs_dialloc_ag(tp, agbp, parent, inop);
+out_error:
+ xfs_perag_put(pag);
+ return XFS_ERROR(error);
+}
+
+/*
* Free disk inode. Carefully avoids touching the incore inode, all
* manipulations incore are the caller's responsibility.
* The on-disk inode is not changed by this operation, only the