I want calculate the NIC rss hash result by function,but the result is not
right, I don't know where the wrong.
struct mbf_cb{
uint32_t sip;
uint32_t dip;
uint16_t sport;
uint16_t dport;
};
static uint8_t test_rss[]={
0x6d,0x5a,0x56,0xda,0x25,0x5b,0x0e,0xc2,
0x41,0x67,0x25,0x3d,0x43,0xa3,0x8f,0xb0,
0xd0,0xca,0x2b,0xcb,0xae,0x7b,0x30,0xb4,
0x77,0xcb,0x2d,0xa3,0x80,0x30,0xf2,0x0c,
0x6a,0x42,0xb7,0x3b,0xbe,0xac,0x01,0xfa,
};
static uint8_t input_mask[]={
0x01,0x02,0x04,0x08,
0x10,0x20,0x40,0x80,
};
mcb.sip=rte_cpu_to_be_32(IPv4(66,9,149,187));
mcb.dip=rte_cpu_to_be_32(IPv4(161,142,100,80));
mcb.sport=rte_cpu_to_be_16(2794);
mcb.dport=rte_cpu_to_be_16(1766);
uint32_t compute_hash(uint8_t *input, int n)
{
int i,j,k;
uint32_t result=0;
uint32_t *lk;
uint8_t rss_key[40];
memcpy(rss_key,test_rss,40);
lk=(uint32_t *)rss_key;
for(i=0;i<n;i++){
for(j=0;j<8;j++){
if((input_mask[j])&input[i]){
result^=*lk;
}
// shift k left 1 bit
rss_key[0]=rss_key[0]<<1;
for(k=1;k<40;k++){
if(rss_key[k]&0x80){
rss_key[k-1]|=0x01;
}
rss_key[k]=rss_key[k]<<1;
}
}
}
return result;
}
printf("rss_hash=%#x\n",compute_hash((uint8_t *)&mcb,sizeof(struct mbf_cb)));
rss_hash=0x57476eca
but the right result is 0x51ccc178
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