On Tue, Dec 4, 2018 at 5:35 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote:
>
> The call to posix_fadvise(POSIX_FADV_WILLNEED) should have the same
> effect as the call to readahead() syscall.
>
> Repeat the test cases for local file and overlayfs file with
> posix_fadvise().
>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
>
Cyril,
PING.
I think this should address all your comments on v4.
Thanks,
Amir.
> .../kernel/syscalls/readahead/readahead02.c | 61 ++++++++++++++-----
> 1 file changed, 45 insertions(+), 16 deletions(-)
>
> diff --git a/testcases/kernel/syscalls/readahead/readahead02.c b/testcases/kernel/syscalls/readahead/readahead02.c
> index de12ba114..d74753dcf 100644
> --- a/testcases/kernel/syscalls/readahead/readahead02.c
> +++ b/testcases/kernel/syscalls/readahead/readahead02.c
> @@ -58,15 +58,34 @@ static struct tst_option options[] = {
> {NULL, NULL, NULL}
> };
>
> +static int libc_readahead(int fd, off_t offset, size_t len)
> +{
> + return readahead(fd, offset, len);
> +}
> +
> +static int fadvise_willneed(int fd, off_t offset, size_t len)
> +{
> + /* Should have the same effect as readahead() syscall */
> + errno = posix_fadvise(fd, offset, len, POSIX_FADV_WILLNEED);
> + /* posix_fadvise returns error number (not in errno) */
> + return errno ? -1 : 0;
> +}
> +
> static struct tcase {
> const char *tname;
> int use_overlay;
> + int use_fadvise;
> + /* Use either readahead() syscall or POSIX_FADV_WILLNEED */
> + int (*readahead)(int, off_t, size_t);
> } tcases[] = {
> - { "readahead on file", 0 },
> - { "readahead on overlayfs file", 1 },
> + { "readahead on file", 0, 0, libc_readahead },
> + { "readahead on overlayfs file", 1, 0, libc_readahead },
> + { "POSIX_FADV_WILLNEED on file", 0, 1, fadvise_willneed },
> + { "POSIX_FADV_WILLNEED on overlayfs file", 1, 1, fadvise_willneed },
> };
>
> static int readahead_supported = 1;
> +static int fadvise_supported = 1;
>
> static int has_file(const char *fname, int required)
> {
> @@ -126,7 +145,6 @@ static void create_testfile(int use_overlay)
> free(tmp);
> }
>
> -
> /* read_testfile - mmap testfile and read every page.
> * This functions measures how many I/O and time it takes to fully
> * read contents of test file.
> @@ -138,7 +156,8 @@ static void create_testfile(int use_overlay)
> * @usec: returns how many microsecond it took to go over fsize bytes
> * @cached: returns cached kB from /proc/meminfo
> */
> -static int read_testfile(int do_readahead, const char *fname, size_t fsize,
> +static int read_testfile(struct tcase *tc, int do_readahead,
> + const char *fname, size_t fsize,
> unsigned long *read_bytes, long long *usec,
> unsigned long *cached)
> {
> @@ -154,7 +173,7 @@ static int read_testfile(int do_readahead, const char *fname, size_t fsize,
> if (do_readahead) {
> cached_start = get_cached_size();
> do {
> - TEST(readahead(fd, offset, fsize - offset));
> + TEST(tc->readahead(fd, offset, fsize - offset));
> if (TST_RET != 0) {
> SAFE_CLOSE(fd);
> return TST_ERR;
> @@ -233,7 +252,8 @@ static void test_readahead(unsigned int n)
> create_testfile(tc->use_overlay);
>
> /* find out how much can cache hold if we read whole file */
> - read_testfile(0, testfile, testfile_size, &read_bytes, &usec, &cached);
> + read_testfile(tc, 0, testfile, testfile_size, &read_bytes, &usec,
> + &cached);
> cached_high = get_cached_size();
> sync();
> drop_caches();
> @@ -241,7 +261,8 @@ static void test_readahead(unsigned int n)
> cached_max = MAX(cached_max, cached_high - cached_low);
>
> tst_res(TINFO, "read_testfile(0)");
> - read_testfile(0, testfile, testfile_size, &read_bytes, &usec, &cached);
> + read_testfile(tc, 0, testfile, testfile_size, &read_bytes, &usec,
> + &cached);
> if (cached > cached_low)
> cached = cached - cached_low;
> else
> @@ -251,20 +272,28 @@ static void test_readahead(unsigned int n)
> drop_caches();
> cached_low = get_cached_size();
> tst_res(TINFO, "read_testfile(1)");
> - ret = read_testfile(1, testfile, testfile_size, &read_bytes_ra,
> + ret = read_testfile(tc, 1, testfile, testfile_size, &read_bytes_ra,
> &usec_ra, &cached_ra);
>
> - if (ret == EINVAL &&
> - (!tc->use_overlay || !readahead_supported)) {
> - readahead_supported = 0;
> - tst_res(TCONF, "readahead not supported on %s",
> - tst_device->fs_type);
> - return;
> + if (ret == EINVAL) {
> + if (tc->use_fadvise &&
> + (!tc->use_overlay || !fadvise_supported)) {
> + fadvise_supported = 0;
> + tst_res(TCONF, "CONFIG_ADVISE_SYSCALLS not configured "
> + "in kernel?");
> + return;
> + } else if (!tc->use_overlay || !readahead_supported) {
> + readahead_supported = 0;
> + tst_res(TCONF, "readahead not supported on %s",
> + tst_device->fs_type);
> + return;
> + }
> }
>
> if (ret) {
> - tst_res(TFAIL | TTERRNO, "readahead failed on %s%s",
> - tc->use_overlay ? "overlayfs on " : "",
> + tst_res(TFAIL | TTERRNO, "%s failed on %s",
> + tc->use_fadvise ? "fadvise" : "readahead",
> + tc->use_overlay ? "overlayfs" :
> tst_device->fs_type);
> return;
> }
> --
> 2.17.1
>
