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talawahtech/txq.bt

Last active May 22, 2021
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txq.bt - monitor the length of an AWS ENA device's transmit queue
#include "txq.h"
kprobe:ena_com_prepare_tx
{
// grab/cast the transmit queue param
$io_sq = (struct ena_com_io_sq *) arg0;
// logic copied from from ena_com_free_q_entries
$queuelen = (uint16) $io_sq->tail - (uint16) $io_sq->next_to_comp;
// Create linear histogram of length of the transmit queue for each pid/queue id combo
@txq[pid, $io_sq->idx] = lhist((uint16) $queuelen, 0, 65, 8);
}
// Had to copy all these dependent stucts so I could define ena_com_io_sq
struct ena_com_io_desc_addr {
u8 __iomem *pbuf_dev_addr; /* LLQ address */
u8 *virt_addr;
dma_addr_t phys_addr;
};
struct ena_com_tx_meta {
u16 mss;
u16 l3_hdr_len;
u16 l3_hdr_offset;
u16 l4_hdr_len; /* In words */
};
struct ena_com_llq_info {
u16 header_location_ctrl;
u16 desc_stride_ctrl;
u16 desc_list_entry_size_ctrl;
u16 desc_list_entry_size;
u16 descs_num_before_header;
u16 descs_per_entry;
u16 max_entries_in_tx_burst;
bool disable_meta_caching;
};
struct ena_com_llq_pkt_ctrl {
u8 *curr_bounce_buf;
u16 idx;
u16 descs_left_in_line;
};
struct ena_com_io_bounce_buffer_control {
u8 *base_buffer;
u16 next_to_use;
u16 buffer_size;
u16 buffers_num; /* Must be a power of 2 */
};
enum queue_direction {
ENA_COM_IO_QUEUE_DIRECTION_TX,
ENA_COM_IO_QUEUE_DIRECTION_RX
};
enum ena_admin_placement_policy_type {
ENA_ADMIN_PLACEMENT_POLICY_HOST = 1,
ENA_ADMIN_PLACEMENT_POLICY_DEV = 3,
};
struct ena_com_io_sq {
struct ena_com_io_desc_addr desc_addr;
void *bus;
u32 __iomem *db_addr;
u8 __iomem *header_addr;
enum queue_direction direction;
enum ena_admin_placement_policy_type mem_queue_type;
bool disable_meta_caching;
u32 msix_vector;
struct ena_com_tx_meta cached_tx_meta;
struct ena_com_llq_info llq_info;
struct ena_com_llq_pkt_ctrl llq_buf_ctrl;
struct ena_com_io_bounce_buffer_control bounce_buf_ctrl;
u16 q_depth;
u16 qid;
u16 idx;
u16 tail;
u16 next_to_comp;
u16 llq_last_copy_tail;
u32 tx_max_header_size;
u8 phase;
u8 desc_entry_size;
u8 dma_addr_bits;
u16 entries_in_tx_burst_left;
};
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