From 35539b54ac339e2b2dee8c74bc9f0b06f11b11cf Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Mon, 20 Jun 2016 13:15:13 -0600 Subject: [PATCH] ntb_perf: clear link_is_up flag when the link goes down. When the link goes down, the link_is_up flag did not return to false. This could have caused some subtle corner case bugs when the link goes up and down quickly. Once that was fixed, there was found to be a race if the link was brought down then immediately up. The link_cleanup work would occasionally be scheduled after the next link up event. This would cancel the link_work that was supposed to occur and leave ntb_perf in an unusable state. To fix this we get rid of the link_cleanup work and put the actions directly in the link_down event. Signed-off-by: Logan Gunthorpe Acked-by: Dave Jiang Signed-off-by: Jon Mason --- drivers/ntb/test/ntb_perf.c | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-) diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c index f0784e50ceb7..6a50f20bf1cd 100644 --- a/drivers/ntb/test/ntb_perf.c +++ b/drivers/ntb/test/ntb_perf.c @@ -133,7 +133,6 @@ struct perf_ctx { spinlock_t db_lock; struct perf_mw mw; bool link_is_up; - struct work_struct link_cleanup; struct delayed_work link_work; wait_queue_head_t link_wq; struct dentry *debugfs_node_dir; @@ -158,10 +157,16 @@ static void perf_link_event(void *ctx) { struct perf_ctx *perf = ctx; - if (ntb_link_is_up(perf->ntb, NULL, NULL) == 1) + if (ntb_link_is_up(perf->ntb, NULL, NULL) == 1) { schedule_delayed_work(&perf->link_work, 2*HZ); - else - schedule_work(&perf->link_cleanup); + } else { + dev_dbg(&perf->ntb->pdev->dev, "link down\n"); + + if (!perf->link_is_up) + cancel_delayed_work_sync(&perf->link_work); + + perf->link_is_up = false; + } } static void perf_db_event(void *ctx, int vec) @@ -547,18 +552,6 @@ out: msecs_to_jiffies(PERF_LINK_DOWN_TIMEOUT)); } -static void perf_link_cleanup(struct work_struct *work) -{ - struct perf_ctx *perf = container_of(work, - struct perf_ctx, - link_cleanup); - - dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__); - - if (!perf->link_is_up) - cancel_delayed_work_sync(&perf->link_work); -} - static int perf_setup_mw(struct ntb_dev *ntb, struct perf_ctx *perf) { struct perf_mw *mw; @@ -787,7 +780,6 @@ static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb) perf_setup_mw(ntb, perf); init_waitqueue_head(&perf->link_wq); INIT_DELAYED_WORK(&perf->link_work, perf_link_work); - INIT_WORK(&perf->link_cleanup, perf_link_cleanup); rc = ntb_set_ctx(ntb, perf, &perf_ops); if (rc) @@ -807,7 +799,6 @@ static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb) err_ctx: cancel_delayed_work_sync(&perf->link_work); - cancel_work_sync(&perf->link_cleanup); kfree(perf); err_perf: return rc; @@ -823,7 +814,6 @@ static void perf_remove(struct ntb_client *client, struct ntb_dev *ntb) mutex_lock(&perf->run_mutex); cancel_delayed_work_sync(&perf->link_work); - cancel_work_sync(&perf->link_cleanup); ntb_clear_ctx(ntb); ntb_link_disable(ntb); -- 2.20.1