From: Marco <ctxspi@gmail.com>
To: xdp-newbies@vger.kernel.org
Subject: Global static volatile
Date: Sat, 30 Mar 2024 15:08:39 +0100 [thread overview]
Message-ID: <CAAVAo4MxNCmEi3A=V+oqyK9_qZ2CBSQAC28g6tAH2t535cSZ4Q@mail.gmail.com> (raw)
Helo
I tried to use a secondary variable fib_params_test as a global
variable at the beginning of my XDP program like this:
static volatile struct bpf_fib_lookup fib_params_test;
.
.
static __always_inline int function_process_packet(struct xdp_md *ctx,
u32 flags)
{
const __u32 ifingress = ctx->ingress_ifindex;
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
void *l3hdr = NULL;
struct bpf_fib_lookup fib_params;
bpf_printk("Ingress interface %d", fib_params_test.ifindex); /*
the value displayed is always right */
.
.
}
Once "fib_params_test" was initialized with the first packet received,
upon subsequent packets coming from different incoming vlan
interfaces, "fib_params_test.ifindex" always returned the interface I
expected.
Obviously I have always done tests with little traffic so I have the
doubt that in a real situation there may be unexpected values for the
fib_params_test.ifindex variable. This is possible?
Thank you.
Marco
next reply other threads:[~2024-03-30 14:08 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-30 14:08 Marco [this message]
2024-03-30 16:11 ` Global static volatile Marco
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