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Date:   Mon, 18 Feb 2019 00:06:37 +0100
From:   Jiri Olsa <jolsa@redhat.com>
To:     Song Liu <songliubraving@fb.com>
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        ast@kernel.org, daniel@iogearbox.net, kernel-team@fb.com,
        peterz@infradead.org, acme@redhat.com, jolsa@kernel.org,
        namhyung@kernel.org
Subject: Re: [PATCH v3 perf,bpf 08/11] perf, bpf: save btf information as
 headers to perf.data
Message-ID: <20190217230637.GK7443@krava>
References: <20190215215354.3114006-1-songliubraving@fb.com>
 <20190215215354.3114006-9-songliubraving@fb.com>
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On Fri, Feb 15, 2019 at 01:53:51PM -0800, Song Liu wrote:

SNIP

> +static int process_btf(struct feat_fd *ff, void *data __maybe_unused)
> +{
> +	struct perf_env *env = &ff->ph->env;
> +	u32 count, i;
> +
> +	if (do_read_u32(ff, &count))
> +		return -1;
> +
> +	down_write(&env->bpf_progs.bpf_info_lock);
> +
> +	for (i = 0; i < count; ++i) {
> +		struct btf_node btf_node;
> +		struct btf_node *node;
> +
> +		if (__do_read(ff, &btf_node, sizeof(struct btf_node)))
> +			return -1;
> +
> +		node = malloc(sizeof(struct btf_node) + btf_node.data_size);
> +		if (!node)
> +			return -1;
> +
> +		node->id = btf_node.id;
> +		node->data_size = btf_node.data_size;
> +
> +		if (__do_read(ff, node->data, btf_node.data_size)) {
> +			free(node);
> +			return -1;
> +		}

hows endianity swap handled got struct btf_node and data in here?

thanks,
jirka