glebfm/strace
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

bpf: remove bpf_priv_data

Browse Source 
As various bpf commands need different data to save between entering
and exiting of the syscall, do not emulate union bpf_attr approach.

* bpf.c (struct bpf_priv_data): Remove.
(DECL_BPF_CMD_DECODER): Remove "struct bpf_priv_data *" argument.
(BEGIN_BPF_CMD_DECODER(BPF_PROG_QUERY)): Use set_tcb_priv_ulong
and get_tcb_priv_ulong to keep bpf_attr.query.prog_cnt field.
(SYS_FUNC(bpf)): Remove priv variable, do not initialize it,
and do not pass it to bpf_cmd_decoders.
This commit is contained in:
Дмитрий Левин 2018-05-26 10:32:54 +00:00
parent ee96027445
commit dae6367f18
1 changed files with 11 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
bpf.c
View File

@ -50,19 +50,12 @@
#include "xlat/ebpf_regs.h"
#include "xlat/numa_node.h"
/** Storage for all the data that is needed to be stored on entering. */
struct bpf_priv_data {
bool bpf_prog_query_stored;
uint32_t bpf_prog_query_prog_cnt;
};
#define DECL_BPF_CMD_DECODER(bpf_cmd_decoder) \
int \
bpf_cmd_decoder(struct tcb *const tcp, \
const kernel_ulong_t addr, \
const unsigned int size, \
void *const data, \
struct bpf_priv_data *priv) \
void *const data) \
/* End of DECL_BPF_CMD_DECODER definition. */
#define BEGIN_BPF_CMD_DECODER(bpf_cmd) \
@ -452,13 +445,7 @@ BEGIN_BPF_CMD_DECODER(BPF_PROG_QUERY)
tprints(", prog_ids=");
if (!priv)
priv = xcalloc(1, sizeof(*priv));
priv->bpf_prog_query_stored = true;
priv->bpf_prog_query_prog_cnt = attr.prog_cnt;
set_tcb_priv_data(tcp, priv, free);
set_tcb_priv_ulong(tcp, attr.prog_cnt);
return 0;
}
@ -469,9 +456,9 @@ BEGIN_BPF_CMD_DECODER(BPF_PROG_QUERY)
print_uint32_array_member, 0);
tprints(", prog_cnt=");
if (priv && priv->bpf_prog_query_stored
&& priv->bpf_prog_query_prog_cnt != attr.prog_cnt)
tprintf("%" PRIu32 " => ", priv->bpf_prog_query_prog_cnt);
const uint32_t prog_cnt_entering = get_tcb_priv_ulong(tcp);
if (prog_cnt_entering != attr.prog_cnt)
tprintf("%" PRIu32 " => ", prog_cnt_entering);
tprintf("%" PRIu32, attr.prog_cnt);
tprints("}");
}
@ -514,30 +501,27 @@ SYS_FUNC(bpf)
BPF_CMD_ENTRY(BPF_RAW_TRACEPOINT_OPEN),
};
static char *buf;
struct bpf_priv_data *priv = NULL;
const unsigned int cmd = tcp->u_arg[0];
const kernel_ulong_t addr = tcp->u_arg[1];
const unsigned int size = tcp->u_arg[2];
int rc = RVAL_DECODED;
if (!buf)
buf = xmalloc(get_pagesize());
if (entering(tcp)) {
printxval_index(bpf_commands, cmd, "BPF_???");
tprints(", ");
} else {
priv = get_tcb_priv_data(tcp);
}
if (size > 0
&& size <= get_pagesize()
&& cmd < ARRAY_SIZE(bpf_cmd_decoders)
&& bpf_cmd_decoders[cmd]) {
static char *buf;
if (!buf)
buf = xmalloc(get_pagesize());
if (!umoven_or_printaddr_ignore_syserror(tcp, addr, size, buf))
rc = bpf_cmd_decoders[cmd](tcp, addr, size, buf, priv);
rc = bpf_cmd_decoders[cmd](tcp, addr, size, buf);
} else {
printaddr(addr);
}