Re: [PATCH v8 4/5] migration: Introduce 'qatzip' compression method

[Prasad Pandit]

Hello,

On Tue, 20 Aug 2024 at 22:40, Yichen Wang <yichen.wang@bytedance.com> wrote:
> +static int qatzip_send_setup(MultiFDSendParams *p, Error **errp)
> +{
> +    QatzipData *q;
> +    QzSessionParamsDeflate_T params;
> +    const char *err_msg;
> +    int ret;
> +
> +    q = g_new0(QatzipData, 1);
> +    p->compress_data = q;
> +    /* We need one extra place for the packet header */
> +    p->iov = g_new0(struct iovec, 2);
> +
> +    /*
> +     * Initialize QAT device with software fallback by default. This allows
> +     * QATzip to use CPU path when QAT hardware reaches maximum throughput.
> +     */
> +    ret = qzInit(&q->sess, true);
> +    if (ret != QZ_OK && ret != QZ_DUPLICATE) {
> +        err_msg = "qzInit failed";
> +        goto err;
> +    }
> +
> +    ret = qzGetDefaultsDeflate(&params);
> +    if (ret != QZ_OK) {
> +        err_msg = "qzGetDefaultsDeflate failed";
> +        goto err;
> +    }
> +
> +    /* Make sure to use configured QATzip compression level. */
> +    params.common_params.comp_lvl = migrate_multifd_qatzip_level();
> +    ret = qzSetupSessionDeflate(&q->sess, &params);
> +    if (ret != QZ_OK && ret != QZ_DUPLICATE) {
> +        err_msg = "qzSetupSessionDeflate failed";
> +        goto err;
> +    }
> +
> +    if (MULTIFD_PACKET_SIZE > UINT32_MAX) {
> +        err_msg = "packet size too large for QAT";
> +        goto err;
> +    }
> +
> +    q->in_len = MULTIFD_PACKET_SIZE;
> +    /*
> +     * PINNED_MEM is an enum from qatzip headers, which means to use
> +     * kzalloc_node() to allocate memory for QAT DMA purposes. When QAT 
> device
> +     * is not available or software fallback is used, the malloc flag needs 
> to
> +     * be set as COMMON_MEM.
> +     */
> +    q->in_buf = qzMalloc(q->in_len, 0, PINNED_MEM);
> +    if (!q->in_buf) {
> +        q->in_buf = qzMalloc(q->in_len, 0, COMMON_MEM);
> +        if (!q->in_buf) {
> +            err_msg = "qzMalloc failed";
> +            goto err;
> +        }
> +    }
> +
> +    q->out_len = qzMaxCompressedLength(MULTIFD_PACKET_SIZE, &q->sess);
> +    q->out_buf = qzMalloc(q->out_len, 0, PINNED_MEM);
> +    if (!q->out_buf) {
> +        q->out_buf = qzMalloc(q->out_len, 0, COMMON_MEM);
> +        if (!q->out_buf) {
> +            err_msg = "qzMalloc failed";
> +            goto err;
> +        }
> +    }
> +
> +    return 0;
> +
> +err:
> +    error_setg(errp, "multifd %u: [sender] %s", p->id, err_msg);
> +    return -1;
> +}

* Need to release (g_free OR qatzip_send_cleanup) allocated memory in
the error (err:) path.


> +static int qatzip_recv_setup(MultiFDRecvParams *p, Error **errp)
> +{
> +    QatzipData *q;
> +    QzSessionParamsDeflate_T params;
> +    const char *err_msg;
> +    int ret;
> +
> +    q = g_new0(QatzipData, 1);
> +    p->compress_data = q;
> +
> +    /*
> +     * Initialize QAT device with software fallback by default. This allows
> +     * QATzip to use CPU path when QAT hardware reaches maximum throughput.
> +     */
> +    ret = qzInit(&q->sess, true);
> +    if (ret != QZ_OK && ret != QZ_DUPLICATE) {
> +        err_msg = "qzInit failed";
> +        goto err;
> +    }
> +
> +    ret = qzGetDefaultsDeflate(&params);
> +    if (ret != QZ_OK) {
> +        err_msg = "qzGetDefaultsDeflate failed";
> +        goto err;
> +    }
> +
> +    ret = qzSetupSessionDeflate(&q->sess, &params);
> +    if (ret != QZ_OK && ret != QZ_DUPLICATE) {
> +        err_msg = "qzSetupSessionDeflate failed";
> +        goto err;
> +    }
> +
> +    /*
> +     * Reserve extra spaces for the incoming packets. Current implementation
> +     * doesn't send uncompressed pages in case the compression gets too big.
> +     */
> +    q->in_len = MULTIFD_PACKET_SIZE * 2;
> +    /*
> +     * PINNED_MEM is an enum from qatzip headers, which means to use
> +     * kzalloc_node() to allocate memory for QAT DMA purposes. When QAT 
> device
> +     * is not available or software fallback is used, the malloc flag needs 
> to
> +     * be set as COMMON_MEM.
> +     */
> +    q->in_buf = qzMalloc(q->in_len, 0, PINNED_MEM);
> +    if (!q->in_buf) {
> +        q->in_buf = qzMalloc(q->in_len, 0, COMMON_MEM);
> +        if (!q->in_buf) {
> +            err_msg = "qzMalloc failed";
> +            goto err;
> +        }
> +    }
> +
> +    q->out_len = MULTIFD_PACKET_SIZE;
> +    q->out_buf = qzMalloc(q->out_len, 0, PINNED_MEM);
> +    if (!q->out_buf) {
> +        q->out_buf = qzMalloc(q->out_len, 0, COMMON_MEM);
> +        if (!q->out_buf) {
> +            err_msg = "qzMalloc failed";
> +            goto err;
> +        }
> +    }
> +
> +    return 0;
> +
> +err:
> +    error_setg(errp, "multifd %u: [receiver] %s", p->id, err_msg);
> +    return -1;
> +}

* Need to release (g_free OR qatzip_recv_cleanup) allocated memory in
the error (err:) path.

Thank you.
---
  - Prasad