I got the following message when running generic/465 on RHEL7.4 --------------------------------------------------------------- QA output created by 465 non-aio dio test encounter an error: block 43 offset 0, content 0 encounter an error: block 0 offset 4096, content 62 encounter an error: block 1 offset 0, content 0 encounter an error: block 17 offset 0, content 0 aio-dio test encounter an error: block 9 offset 0, content 0 encounter an error: block 2 offset 0, content 0 encounter an error: block 0 offset 4096, content 62 encounter an error: block 12 offset 0, content 0 --------------------------------------------------------------- It is possible that dio read reads less than 1M data while dio write is writing 1M data into file, because concurrent dio read/write to the same file cannot guarantee atomicity and may split specified size. Please see this URL for detailed explanation: https://marc.info/?l=linux-fsdevel&m=151053542926457&w=2 We can just check the actual read data instead of the whole read buffer. Signed-off-by: Xiao Yang <yangx.jy@xxxxxxxxxxxxxx> --- src/aio-dio-regress/aio-dio-append-write-read-race.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/src/aio-dio-regress/aio-dio-append-write-read-race.c b/src/aio-dio-regress/aio-dio-append-write-read-race.c index 8f94d50..848755c 100644 --- a/src/aio-dio-regress/aio-dio-append-write-read-race.c +++ b/src/aio-dio-regress/aio-dio-append-write-read-race.c @@ -46,6 +46,7 @@ struct io_data { }; int reader_ready = 0; +static volatile int act_rd_sz; static void usage(const char *prog) { @@ -57,15 +58,15 @@ static void usage(const char *prog) static void *reader(void *arg) { struct io_data *data = (struct io_data *)arg; - int ret; + act_rd_sz = 0; memset(data->buf, 'b', data->blksize); reader_ready = 1; do { - ret = pread(data->fd, data->buf, data->blksize, data->offset); - if (ret < 0) + act_rd_sz = pread(data->fd, data->buf, data->blksize, data->offset); + if (act_rd_sz < 0) perror("read file"); - } while (ret <= 0); + } while (act_rd_sz <= 0); return NULL; } @@ -203,7 +204,7 @@ int main(int argc, char *argv[]) goto err; } - for (j = 0; j < blksize; j++) { + for (j = 0; j < act_rd_sz; j++) { if (rdata.buf[j] != 'a') { fail("encounter an error: " "block %d offset %d, content %x\n", -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe fstests" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
