#include "xfs_alloc.h"
#include "xfs_discard.h"
-/*
- * Perform initial CIL structure initialisation.
- */
-int
-xlog_cil_init(
- struct log *log)
-{
- struct xfs_cil *cil;
- struct xfs_cil_ctx *ctx;
-
- cil = kmem_zalloc(sizeof(*cil), KM_SLEEP|KM_MAYFAIL);
- if (!cil)
- return ENOMEM;
-
- ctx = kmem_zalloc(sizeof(*ctx), KM_SLEEP|KM_MAYFAIL);
- if (!ctx) {
- kmem_free(cil);
- return ENOMEM;
- }
-
- INIT_LIST_HEAD(&cil->xc_cil);
- INIT_LIST_HEAD(&cil->xc_committing);
- spin_lock_init(&cil->xc_cil_lock);
- init_rwsem(&cil->xc_ctx_lock);
- init_waitqueue_head(&cil->xc_commit_wait);
-
- INIT_LIST_HEAD(&ctx->committing);
- INIT_LIST_HEAD(&ctx->busy_extents);
- ctx->sequence = 1;
- ctx->cil = cil;
- cil->xc_ctx = ctx;
- cil->xc_current_sequence = ctx->sequence;
-
- cil->xc_log = log;
- log->l_cilp = cil;
- return 0;
-}
-
-void
-xlog_cil_destroy(
- struct log *log)
-{
- if (log->l_cilp->xc_ctx) {
- if (log->l_cilp->xc_ctx->ticket)
- xfs_log_ticket_put(log->l_cilp->xc_ctx->ticket);
- kmem_free(log->l_cilp->xc_ctx);
- }
-
- ASSERT(list_empty(&log->l_cilp->xc_cil));
- kmem_free(log->l_cilp);
-}
-
/*
* Allocate a new ticket. Failing to get a new ticket makes it really hard to
* recover, so we don't allow failure here. Also, we allocate in a context that
*/
STATIC int
xlog_cil_push(
- struct log *log,
- xfs_lsn_t push_seq)
+ struct log *log)
{
struct xfs_cil *cil = log->l_cilp;
struct xfs_log_vec *lv;
struct xfs_log_iovec lhdr;
struct xfs_log_vec lvhdr = { NULL };
xfs_lsn_t commit_lsn;
+ xfs_lsn_t push_seq;
if (!cil)
return 0;
- ASSERT(!push_seq || push_seq <= cil->xc_ctx->sequence);
-
new_ctx = kmem_zalloc(sizeof(*new_ctx), KM_SLEEP|KM_NOFS);
new_ctx->ticket = xlog_cil_ticket_alloc(log);
- /*
- * Lock out transaction commit, but don't block for background pushes
- * unless we are well over the CIL space limit. See the definition of
- * XLOG_CIL_HARD_SPACE_LIMIT() for the full explanation of the logic
- * used here.
- */
- if (!down_write_trylock(&cil->xc_ctx_lock)) {
- if (!push_seq &&
- cil->xc_ctx->space_used < XLOG_CIL_HARD_SPACE_LIMIT(log))
- goto out_free_ticket;
- down_write(&cil->xc_ctx_lock);
- }
+ down_write(&cil->xc_ctx_lock);
ctx = cil->xc_ctx;
- /* check if we've anything to push */
- if (list_empty(&cil->xc_cil))
- goto out_skip;
+ spin_lock(&cil->xc_cil_lock);
+ push_seq = cil->xc_push_seq;
+ ASSERT(push_seq <= ctx->sequence);
- /* check for spurious background flush */
- if (!push_seq && cil->xc_ctx->space_used < XLOG_CIL_SPACE_LIMIT(log))
+ /*
+ * Check if we've anything to push. If there is nothing, then we don't
+ * move on to a new sequence number and so we have to be able to push
+ * this sequence again later.
+ */
+ if (list_empty(&cil->xc_cil)) {
+ cil->xc_push_seq = 0;
+ spin_unlock(&cil->xc_cil_lock);
goto out_skip;
+ }
+ spin_unlock(&cil->xc_cil_lock);
+
/* check for a previously pushed seqeunce */
- if (push_seq && push_seq < cil->xc_ctx->sequence)
+ if (push_seq < cil->xc_ctx->sequence)
goto out_skip;
/*
out_skip:
up_write(&cil->xc_ctx_lock);
-out_free_ticket:
xfs_log_ticket_put(new_ctx->ticket);
kmem_free(new_ctx);
return 0;
return XFS_ERROR(EIO);
}
+static void
+xlog_cil_push_work(
+ struct work_struct *work)
+{
+ struct xfs_cil *cil = container_of(work, struct xfs_cil,
+ xc_push_work);
+ xlog_cil_push(cil->xc_log);
+}
+
+/*
+ * We need to push CIL every so often so we don't cache more than we can fit in
+ * the log. The limit really is that a checkpoint can't be more than half the
+ * log (the current checkpoint is not allowed to overwrite the previous
+ * checkpoint), but commit latency and memory usage limit this to a smaller
+ * size.
+ */
+static void
+xlog_cil_push_background(
+ struct log *log)
+{
+ struct xfs_cil *cil = log->l_cilp;
+
+ /*
+ * The cil won't be empty because we are called while holding the
+ * context lock so whatever we added to the CIL will still be there
+ */
+ ASSERT(!list_empty(&cil->xc_cil));
+
+ /*
+ * don't do a background push if we haven't used up all the
+ * space available yet.
+ */
+ if (cil->xc_ctx->space_used < XLOG_CIL_SPACE_LIMIT(log))
+ return;
+
+ spin_lock(&cil->xc_cil_lock);
+ if (cil->xc_push_seq < cil->xc_current_sequence) {
+ cil->xc_push_seq = cil->xc_current_sequence;
+ queue_work(log->l_mp->m_cil_workqueue, &cil->xc_push_work);
+ }
+ spin_unlock(&cil->xc_cil_lock);
+
+}
+
+static void
+xlog_cil_push_foreground(
+ struct log *log,
+ xfs_lsn_t push_seq)
+{
+ struct xfs_cil *cil = log->l_cilp;
+
+ if (!cil)
+ return;
+
+ ASSERT(push_seq && push_seq <= cil->xc_current_sequence);
+
+ /* start on any pending background push to minimise wait time on it */
+ flush_work(&cil->xc_push_work);
+
+ /*
+ * If the CIL is empty or we've already pushed the sequence then
+ * there's no work we need to do.
+ */
+ spin_lock(&cil->xc_cil_lock);
+ if (list_empty(&cil->xc_cil) || push_seq <= cil->xc_push_seq) {
+ spin_unlock(&cil->xc_cil_lock);
+ return;
+ }
+
+ cil->xc_push_seq = push_seq;
+ spin_unlock(&cil->xc_cil_lock);
+
+ /* do the push now */
+ xlog_cil_push(log);
+}
+
/*
* Commit a transaction with the given vector to the Committed Item List.
*
{
struct log *log = mp->m_log;
int log_flags = 0;
- int push = 0;
struct xfs_log_vec *log_vector;
if (flags & XFS_TRANS_RELEASE_LOG_RES)
*/
xfs_trans_free_items(tp, *commit_lsn, 0);
- /* check for background commit before unlock */
- if (log->l_cilp->xc_ctx->space_used > XLOG_CIL_SPACE_LIMIT(log))
- push = 1;
+ xlog_cil_push_background(log);
up_read(&log->l_cilp->xc_ctx_lock);
-
- /*
- * We need to push CIL every so often so we don't cache more than we
- * can fit in the log. The limit really is that a checkpoint can't be
- * more than half the log (the current checkpoint is not allowed to
- * overwrite the previous checkpoint), but commit latency and memory
- * usage limit this to a smaller size in most cases.
- */
- if (push)
- xlog_cil_push(log, 0);
return 0;
}
*
* We return the current commit lsn to allow the callers to determine if a
* iclog flush is necessary following this call.
- *
- * XXX: Initially, just push the CIL unconditionally and return whatever
- * commit lsn is there. It'll be empty, so this is broken for now.
*/
xfs_lsn_t
xlog_cil_force_lsn(
* xlog_cil_push() handles racing pushes for the same sequence,
* so no need to deal with it here.
*/
- if (sequence == cil->xc_current_sequence)
- xlog_cil_push(log, sequence);
+ xlog_cil_push_foreground(log, sequence);
/*
* See if we can find a previous sequence still committing.
return false;
return true;
}
+
+/*
+ * Perform initial CIL structure initialisation.
+ */
+int
+xlog_cil_init(
+ struct log *log)
+{
+ struct xfs_cil *cil;
+ struct xfs_cil_ctx *ctx;
+
+ cil = kmem_zalloc(sizeof(*cil), KM_SLEEP|KM_MAYFAIL);
+ if (!cil)
+ return ENOMEM;
+
+ ctx = kmem_zalloc(sizeof(*ctx), KM_SLEEP|KM_MAYFAIL);
+ if (!ctx) {
+ kmem_free(cil);
+ return ENOMEM;
+ }
+
+ INIT_WORK(&cil->xc_push_work, xlog_cil_push_work);
+ INIT_LIST_HEAD(&cil->xc_cil);
+ INIT_LIST_HEAD(&cil->xc_committing);
+ spin_lock_init(&cil->xc_cil_lock);
+ init_rwsem(&cil->xc_ctx_lock);
+ init_waitqueue_head(&cil->xc_commit_wait);
+
+ INIT_LIST_HEAD(&ctx->committing);
+ INIT_LIST_HEAD(&ctx->busy_extents);
+ ctx->sequence = 1;
+ ctx->cil = cil;
+ cil->xc_ctx = ctx;
+ cil->xc_current_sequence = ctx->sequence;
+
+ cil->xc_log = log;
+ log->l_cilp = cil;
+ return 0;
+}
+
+void
+xlog_cil_destroy(
+ struct log *log)
+{
+ if (log->l_cilp->xc_ctx) {
+ if (log->l_cilp->xc_ctx->ticket)
+ xfs_log_ticket_put(log->l_cilp->xc_ctx->ticket);
+ kmem_free(log->l_cilp->xc_ctx);
+ }
+
+ ASSERT(list_empty(&log->l_cilp->xc_cil));
+ kmem_free(log->l_cilp);
+}
+
projects / linux-beck.git / commitdiff