Commit 54fced03 authored by John Snow's avatar John Snow
Browse files

ahci-test: improve rw buffer patterns 



My pattern was cyclical every 256 bytes, so it missed a fairly obvious
failure case. Add some rand() pepper into the test pattern, and for large
patterns that exceed 256 sectors, start writing an ID per-sector so that
we never generate identical sector patterns.

Signed-off-by: default avatarJohn Snow <jsnow@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Tested-by: default avatarAndreas Färber <afaerber@suse.de>
Message-id: 1426811056-2202-5-git-send-email-jsnow@redhat.com
parent ac381236

tests/ahci-test.c

+28 −8
Original line number Diff line number Diff line
@@ -68,6 +68,32 @@ static void string_bswap16(uint16_t *s, size_t bytes) 
    }

}



static void generate_pattern(void *buffer, size_t len, size_t cycle_len)

{

    int i, j;

    unsigned char *tx = (unsigned char *)buffer;

    unsigned char p;

    size_t *sx;



    /* Write an indicative pattern that varies and is unique per-cycle */

    p = rand() % 256;

    for (i = j = 0; i < len; i++, j++) {

        tx[i] = p;

        if (j % cycle_len == 0) {

            p = rand() % 256;

        }

    }



    /* force uniqueness by writing an id per-cycle */

    for (i = 0; i < len / cycle_len; i++) {

        j = i * cycle_len;

        if (j + sizeof(*sx) <= len) {

            sx = (size_t *)&tx[j];

            *sx = i;

        }

    }

}



/*** Test Setup & Teardown ***/



/**
@@ -736,7 +762,6 @@ static void ahci_test_io_rw_simple(AHCIQState *ahci, unsigned bufsize, 
{

    uint64_t ptr;

    uint8_t port;

    unsigned i;

    unsigned char *tx = g_malloc(bufsize);

    unsigned char *rx = g_malloc0(bufsize);
@@ -752,9 +777,7 @@ static void ahci_test_io_rw_simple(AHCIQState *ahci, unsigned bufsize, 
    g_assert(ptr);



    /* Write some indicative pattern to our buffer. */

    for (i = 0; i < bufsize; i++) {

        tx[i] = (bufsize - i);

    }

    generate_pattern(tx, bufsize, AHCI_SECTOR_SIZE);

    memwrite(ptr, tx, bufsize);



    /* Write this buffer to disk, then read it back to the DMA buffer. */
@@ -865,7 +888,6 @@ static void test_dma_fragmented(void) 
    size_t bufsize = 4096;

    unsigned char *tx = g_malloc(bufsize);

    unsigned char *rx = g_malloc0(bufsize);

    unsigned i;

    uint64_t ptr;



    ahci = ahci_boot_and_enable();
@@ -873,9 +895,7 @@ static void test_dma_fragmented(void) 
    ahci_port_clear(ahci, px);



    /* create pattern */

    for (i = 0; i < bufsize; i++) {

        tx[i] = (bufsize - i);

    }

    generate_pattern(tx, bufsize, AHCI_SECTOR_SIZE);



    /* Create a DMA buffer in guest memory, and write our pattern to it. */

    ptr = guest_alloc(ahci->parent->alloc, bufsize);