diff options
Diffstat (limited to 'src/block/block_write.c')
-rw-r--r-- | src/block/block_write.c | 81 |
1 files changed, 27 insertions, 54 deletions
diff --git a/src/block/block_write.c b/src/block/block_write.c index 30d06e6259a..7e5b027ce2b 100644 --- a/src/block/block_write.c +++ b/src/block/block_write.c @@ -82,22 +82,18 @@ __wt_block_extend(WT_SESSION_IMPL *session, WT_BLOCK *block, { WT_DECL_RET; WT_FILE_HANDLE *handle; - bool locked; /* * The locking in this function is messy: by definition, the live system * is locked when we're called, but that lock may have been acquired by * our caller or our caller's caller. If our caller's lock, release_lock - * comes in set, indicating this function can unlock it before returning - * (either before extending the file or afterward, depending on the call - * used). If it is our caller's caller, then release_lock comes in not - * set, indicating it cannot be released here. + * comes in set and this function can unlock it before returning (so it + * isn't held while extending the file). If it is our caller's caller, + * then release_lock comes in not set, indicating it cannot be released + * here. * - * If we unlock here, we clear release_lock. But if we then find out we - * need a lock after all, we re-acquire the lock and set release_lock so - * our caller knows to release it. + * If we unlock here, we clear release_lock. */ - locked = true; /* If not configured to extend the file, we're done. */ if (block->extend_len == 0) @@ -122,62 +118,39 @@ __wt_block_extend(WT_SESSION_IMPL *session, WT_BLOCK *block, * used to extend the file initialize the extended space. If a writing * thread races with the extending thread, the extending thread might * overwrite already written data, and that would be very, very bad. - * - * Some variants of the system call to extend the file fail at run-time - * based on the filesystem type, fall back to ftruncate in that case, - * and remember that ftruncate requires locking. */ handle = fh->handle; - if (handle->fh_allocate != NULL || - handle->fh_allocate_nolock != NULL) { - /* - * Release any locally acquired lock if not needed to extend the - * file, extending the file may require updating on-disk file's - * metadata, which can be slow. (It may be a bad idea to - * configure for file extension on systems that require locking - * over the extend call.) - */ - if (handle->fh_allocate_nolock != NULL && *release_lockp) { - *release_lockp = locked = false; - __wt_spin_unlock(session, &block->live_lock); - } - - /* - * Extend the file: there's a race between setting the value of - * extend_size and doing the extension, but it should err on the - * side of extend_size being smaller than the actual file size, - * and that's OK, we simply may do another extension sooner than - * otherwise. - */ - block->extend_size = block->size + block->extend_len * 2; - if ((ret = __wt_fallocate( - session, fh, block->size, block->extend_len * 2)) == 0) - return (0); - WT_RET_ERROR_OK(ret, ENOTSUP); - } + if (handle->fh_extend == NULL && handle->fh_extend_nolock == NULL) + return (0); /* - * We may have a caller lock or a locally acquired lock, but we need a - * lock to call ftruncate. + * Set the extend_size before releasing the lock, I don't want to read + * and manipulate multiple values without holding a lock. + * + * There's a race between the calculation and doing the extension, but + * it should err on the side of extend_size being smaller than the + * actual file size, and that's OK, we simply may do another extension + * sooner than otherwise. */ - if (!locked) { - __wt_spin_lock(session, &block->live_lock); - *release_lockp = true; - } + block->extend_size = block->size + block->extend_len * 2; /* - * The underlying truncate call initializes allocated space, reset the - * extend length after locking so we don't overwrite already-written - * blocks. + * Release any locally acquired lock if not needed to extend the file, + * extending the file may require updating on-disk file's metadata, + * which can be slow. (It may be a bad idea to configure for file + * extension on systems that require locking over the extend call.) */ - block->extend_size = block->size + block->extend_len * 2; + if (handle->fh_extend_nolock != NULL && *release_lockp) { + *release_lockp = false; + __wt_spin_unlock(session, &block->live_lock); + } /* - * The truncate might fail if there's a mapped file (in other words, if - * there's an open checkpoint on the file), that's OK. + * The extend might fail (for example, the file is mapped into memory), + * or discover file extension isn't supported; both are OK. */ - WT_RET_BUSY_OK(__wt_ftruncate(session, fh, block->extend_size)); - return (0); + ret = __wt_fextend(session, fh, block->extend_size); + return (ret == EBUSY || ret == ENOTSUP ? 0 : ret); } /* |