Commit fd2ecd88 authored by Logan Gunthorpe's avatar Logan Gunthorpe Committed by Jon Mason
Browse files

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: default avatarLogan Gunthorpe <>
Acked-by: default avatarDave Jiang <>
Signed-off-by: default avatarJon Mason <>
parent 19645a07
......@@ -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;
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