Commit 1c450366 authored by Anton Nefedov's avatar Anton Nefedov Committed by Max Reitz
Browse files

file-posix: account discard operations 



This will help to identify how many of the user-issued discard operations
(accounted on a device level) have actually suceeded down on the host file
(even though the numbers will not be exactly the same if non-raw format
driver is used (e.g. qcow2 sending metadata discards)).

Note that these numbers will not include discards triggered by
write-zeroes + MAY_UNMAP calls.

Signed-off-by: default avatarAnton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190923121737.83281-9-anton.nefedov@virtuozzo.com
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent 4989ef57

block/file-posix.c

+21 −1
Original line number Diff line number Diff line
@@ -161,6 +161,11 @@ typedef struct BDRVRawState { 
    bool needs_alignment;

    bool drop_cache;

    bool check_cache_dropped;

    struct {

        uint64_t discard_nb_ok;

        uint64_t discard_nb_failed;

        uint64_t discard_bytes_ok;

    } stats;



    PRManager *pr_mgr;

} BDRVRawState;
@@ -2660,11 +2665,22 @@ static void coroutine_fn raw_co_invalidate_cache(BlockDriverState *bs, 
#endif /* !__linux__ */

}



static void raw_account_discard(BDRVRawState *s, uint64_t nbytes, int ret)

{

    if (ret) {

        s->stats.discard_nb_failed++;

    } else {

        s->stats.discard_nb_ok++;

        s->stats.discard_bytes_ok += nbytes;

    }

}



static coroutine_fn int

raw_do_pdiscard(BlockDriverState *bs, int64_t offset, int bytes, bool blkdev)

{

    BDRVRawState *s = bs->opaque;

    RawPosixAIOData acb;

    int ret;



    acb = (RawPosixAIOData) {

        .bs             = bs,
@@ -2678,7 +2694,9 @@ raw_do_pdiscard(BlockDriverState *bs, int64_t offset, int bytes, bool blkdev) 
        acb.aio_type |= QEMU_AIO_BLKDEV;

    }



    return raw_thread_pool_submit(bs, handle_aiocb_discard, &acb);

    ret = raw_thread_pool_submit(bs, handle_aiocb_discard, &acb);

    raw_account_discard(s, bytes, ret);

    return ret;

}



static coroutine_fn int
@@ -3301,10 +3319,12 @@ static int fd_open(BlockDriverState *bs) 
static coroutine_fn int

hdev_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes)

{

    BDRVRawState *s = bs->opaque;

    int ret;



    ret = fd_open(bs);

    if (ret < 0) {

        raw_account_discard(s, bytes, ret);

        return ret;

    }

    return raw_do_pdiscard(bs, offset, bytes, true);