pahole: Introduce --with_flexible_array option to show just types ending in a flexible array
The kernel has lotsa:
$ pahole --sizes --with_flexible_array | wc -l
1134
$
$ pahole --with_flexible_array | tail -18
struct pci_setup_rom {
struct setup_data data; /* 0 16 */
uint16_t vendor; /* 16 2 */
uint16_t devid; /* 18 2 */
/* XXX 4 bytes hole, try to pack */
uint64_t pcilen; /* 24 8 */
long unsigned int segment; /* 32 8 */
long unsigned int bus; /* 40 8 */
long unsigned int device; /* 48 8 */
long unsigned int function; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
uint8_t romdata[]; /* 64 0 */
/* size: 64, cachelines: 1, members: 9 */
/* sum members: 60, holes: 1, sum holes: 4 */
};
$
Works together with other filters:
$ pahole --contains setup_data --with_flexible_array
pci_setup_rom
$ pahole pci_setup_rom
struct pci_setup_rom {
struct setup_data data; /* 0 16 */
uint16_t vendor; /* 16 2 */
uint16_t devid; /* 18 2 */
/* XXX 4 bytes hole, try to pack */
uint64_t pcilen; /* 24 8 */
long unsigned int segment; /* 32 8 */
long unsigned int bus; /* 40 8 */
long unsigned int device; /* 48 8 */
long unsigned int function; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
uint8_t romdata[]; /* 64 0 */
/* size: 64, cachelines: 1, members: 9 */
/* sum members: 60, holes: 1, sum holes: 4 */
};
$
$ pahole --find_pointers_to net_device --with_flexible_array
neighbour: dev
pneigh_entry: dev
xsk_buff_pool: netdev
cfg80211_sched_scan_request: dev
switchdev_deferred_item: dev
$ pahole xsk_buff_pool
struct xsk_buff_pool {
struct device * dev; /* 0 8 */
struct net_device * netdev; /* 8 8 */
struct list_head xsk_tx_list; /* 16 16 */
spinlock_t xsk_tx_list_lock; /* 32 4 */
refcount_t users; /* 36 4 */
struct xdp_umem * umem; /* 40 8 */
struct work_struct work; /* 48 32 */
/* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */
struct list_head free_list; /* 80 16 */
u32 heads_cnt; /* 96 4 */
u16 queue_id; /* 100 2 */
/* XXX 26 bytes hole, try to pack */
/* --- cacheline 2 boundary (128 bytes) --- */
struct xsk_queue * fq; /* 128 8 */
struct xsk_queue * cq; /* 136 8 */
dma_addr_t * dma_pages; /* 144 8 */
struct xdp_buff_xsk * heads; /* 152 8 */
u64 chunk_mask; /* 160 8 */
u64 addrs_cnt; /* 168 8 */
u32 free_list_cnt; /* 176 4 */
u32 dma_pages_cnt; /* 180 4 */
u32 free_heads_cnt; /* 184 4 */
u32 headroom; /* 188 4 */
/* --- cacheline 3 boundary (192 bytes) --- */
u32 chunk_size; /* 192 4 */
u32 frame_len; /* 196 4 */
u8 cached_need_wakeup; /* 200 1 */
bool uses_need_wakeup; /* 201 1 */
bool dma_need_sync; /* 202 1 */
bool unaligned; /* 203 1 */
/* XXX 4 bytes hole, try to pack */
void * addrs; /* 208 8 */
spinlock_t cq_lock; /* 216 4 */
/* XXX 4 bytes hole, try to pack */
struct xdp_buff_xsk * free_heads[]; /* 224 0 */
/* size: 256, cachelines: 4, members: 29 */
/* sum members: 190, holes: 3, sum holes: 34 */
/* padding: 32 */
};
$
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
7eea706c14