From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Sun, 25 Nov 2018 21:48:24 -0500 Subject: [lustre-devel] [PATCH 08/12] lustre: mdc: propagate changelog errors to readers In-Reply-To: <1543200508-6838-1-git-send-email-jsimmons@infradead.org> References: <1543200508-6838-1-git-send-email-jsimmons@infradead.org> Message-ID: <1543200508-6838-9-git-send-email-jsimmons@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org From: "John L. Hammond" Store errors encountered by the changelog llog reader thread in the crs_err field of struct changelog_reader_state so that they can be propageted to changelog readers. In chlg_read() improve the error and EOF reporting. Return -ERESTARTSYS when the blocked reader is interrupted. Replace uses of wait_event_idle() with ait_event_interruptible(). Signed-off-by: John L. Hammond WC-bug-id: https://jira.whamcloud.com/browse/LU-10218 Reviewed-on: https://review.whamcloud.com/30040 Reviewed-by: Quentin Bouget Reviewed-by: Henri Doreau Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- drivers/staging/lustre/lustre/mdc/mdc_changelog.c | 45 ++++++++++++++--------- 1 file changed, 28 insertions(+), 17 deletions(-) diff --git a/drivers/staging/lustre/lustre/mdc/mdc_changelog.c b/drivers/staging/lustre/lustre/mdc/mdc_changelog.c index becdee8..811a36a 100644 --- a/drivers/staging/lustre/lustre/mdc/mdc_changelog.c +++ b/drivers/staging/lustre/lustre/mdc/mdc_changelog.c @@ -71,7 +71,7 @@ struct chlg_reader_state { /* Producer thread (if any) */ struct task_struct *crs_prod_task; /* An error occurred that prevents from reading further */ - bool crs_err; + int crs_err; /* EOF, no more records available */ bool crs_eof; /* Desired start position */ @@ -148,9 +148,9 @@ static int chlg_read_cat_process_cb(const struct lu_env *env, PFID(&rec->cr.cr_tfid), PFID(&rec->cr.cr_pfid), rec->cr.cr_namelen, changelog_rec_name(&rec->cr)); - wait_event_idle(crs->crs_waitq_prod, - (crs->crs_rec_count < CDEV_CHLG_MAX_PREFETCH || - kthread_should_stop())); + wait_event_interruptible(crs->crs_waitq_prod, + crs->crs_rec_count < CDEV_CHLG_MAX_PREFETCH || + kthread_should_stop()); if (kthread_should_stop()) return LLOG_PROC_BREAK; @@ -231,7 +231,7 @@ static int chlg_load(void *args) err_out: if (rc < 0) - crs->crs_err = true; + crs->crs_err = rc; wake_up_all(&crs->crs_waitq_cons); @@ -241,7 +241,7 @@ static int chlg_load(void *args) if (ctx) llog_ctxt_put(ctx); - wait_event_idle(crs->crs_waitq_prod, kthread_should_stop()); + wait_event_interruptible(crs->crs_waitq_prod, kthread_should_stop()); return rc; } @@ -264,13 +264,20 @@ static ssize_t chlg_read(struct file *file, char __user *buff, size_t count, struct chlg_reader_state *crs = file->private_data; struct chlg_rec_entry *rec; struct chlg_rec_entry *tmp; - ssize_t written_total = 0; + ssize_t written_total = 0; LIST_HEAD(consumed); + size_t rc; + + if (file->f_flags & O_NONBLOCK && crs->crs_rec_count == 0) { + if (crs->crs_err < 0) + return crs->crs_err; + else if (crs->crs_eof) + return 0; + else + return -EAGAIN; + } - if (file->f_flags & O_NONBLOCK && crs->crs_rec_count == 0) - return -EAGAIN; - - wait_event_idle(crs->crs_waitq_cons, + rc = wait_event_interruptible(crs->crs_waitq_cons, crs->crs_rec_count > 0 || crs->crs_eof || crs->crs_err); mutex_lock(&crs->crs_lock); @@ -279,8 +286,7 @@ static ssize_t chlg_read(struct file *file, char __user *buff, size_t count, break; if (copy_to_user(buff, rec->enq_record, rec->enq_length)) { - if (written_total == 0) - written_total = -EFAULT; + rc = -EFAULT; break; } @@ -294,15 +300,19 @@ static ssize_t chlg_read(struct file *file, char __user *buff, size_t count, } mutex_unlock(&crs->crs_lock); - if (written_total > 0) + if (written_total > 0) { + rc = written_total; wake_up_all(&crs->crs_waitq_prod); + } else if (rc == 0) { + rc = crs->crs_err; + } list_for_each_entry_safe(rec, tmp, &consumed, enq_linkage) enq_record_delete(rec); *ppos = crs->crs_start_offset; - return written_total; + return rc; } /** @@ -509,15 +519,16 @@ static int chlg_release(struct inode *inode, struct file *file) struct chlg_reader_state *crs = file->private_data; struct chlg_rec_entry *rec; struct chlg_rec_entry *tmp; + int rc = 0; if (crs->crs_prod_task) - kthread_stop(crs->crs_prod_task); + rc = kthread_stop(crs->crs_prod_task); list_for_each_entry_safe(rec, tmp, &crs->crs_rec_queue, enq_linkage) enq_record_delete(rec); kfree(crs); - return 0; + return rc; } /** -- 1.8.3.1