From fd2ecd885bab8e456298d0b702806ea736456c62 Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Mon, 20 Jun 2016 13:15:04 -0600 Subject: [PATCH] ntb_perf: Schedule based on time not on performance When debugging performance problems, if some issue causes the ntb hardware to be significantly slower than expected, ntb_perf will hang requiring a reboot because it only schedules once every 4GB. Instead, schedule based on jiffies so it will not hang the CPU if the transfer is slow. Signed-off-by: Logan Gunthorpe Acked-by: Dave Jiang Signed-off-by: Jon Mason --- drivers/ntb/test/ntb_perf.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c index 4368519da102..5008ccf600a9 100644 --- a/drivers/ntb/test/ntb_perf.c +++ b/drivers/ntb/test/ntb_perf.c @@ -273,6 +273,7 @@ static int perf_move_data(struct pthr_ctx *pctx, char __iomem *dst, char *src, char __iomem *tmp = dst; u64 perf, diff_us; ktime_t kstart, kstop, kdiff; + unsigned long last_sleep = jiffies; chunks = div64_u64(win_size, buf_size); total_chunks = div64_u64(total, buf_size); @@ -288,8 +289,9 @@ static int perf_move_data(struct pthr_ctx *pctx, char __iomem *dst, char *src, } else tmp += buf_size; - /* Probably should schedule every 4GB to prevent soft hang. */ - if (((copied % SZ_4G) == 0) && !use_dma) { + /* Probably should schedule every 5s to prevent soft hang. */ + if (unlikely((jiffies - last_sleep) > 5 * HZ)) { + last_sleep = jiffies; set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(1); } -- 2.30.2