[ofa-general] Re: [PATCH] osm: Converting the the C++ code to C in osm_ucast_lash.c

[Yevgeny Kliteynik]

Michael S. Tsirkin wrote:
>> Hi Hal.
>>
>> Converting the the C++ code to C.
>>
>> Please apply both to trunk and to 1.2
>>
>> Thanks.
>>
>> Signed-off-by: Yevgeny Kliteynik <kliteyn at dev.mellanox.co.il>
> 
> NAK.
> 1. I don't see any C++ here.
> 
> 2. Why do we need this on ofed branch?
>    Only bugfixes should go there. What bug does it fix?

There are 3 things in this patch:
1. int i -> uint16_t i
2. Moving variable declaration (switch_bitmap) to the beginning 
   of the function (currently, it is declared after OSM_LOG_ENTER)
3. Changing C99 dynamically allocated array to the old style.

First two can be categorized as bugs.
The third one is for compiler on windows.

Each of these elements breaks OSM compilation on Windows.

If we don't include either of these, then OFED 1.2 OpenSM compilation
on windows will be broken. 

-- Yevgeny
 
>> ---
>>  osm/opensm/osm_ucast_lash.c |   23 ++++++++++++++++-------
>>  1 files changed, 16 insertions(+), 7 deletions(-)
>>
>> diff --git a/osm/opensm/osm_ucast_lash.c b/osm/opensm/osm_ucast_lash.c
>> index 0afa43c..8c9172e 100644
>> --- a/osm/opensm/osm_ucast_lash.c
>> +++ b/osm/opensm/osm_ucast_lash.c
>> @@ -406,7 +406,7 @@ static int get_phys_connection(switch_t
>>  static void shortest_path(lash_t *p_lash, int ir)
>>  {
>>    switch_t **switches = p_lash->switches, *sw, *swi;
>> -  int i;
>> +  uint16_t i;
>>    cl_list_t bfsq;
>>    
>>    cl_list_construct(&bfsq);
>> @@ -986,11 +986,18 @@ static int lash_core(lash_t *p_lash)
>>    int output_link2, i_next_switch2;
>>    int cycle_found2 = 0;
>>    int status = IB_SUCCESS;
>> +  int * switch_bitmap = NULL;
>>  
>>    OSM_LOG_ENTER(p_log, lash_core);
>>  
>> -  //Bitmap to check if we have processed this pair
>> -  int switch_bitmap[num_switches][num_switches];
>> +  switch_bitmap = (int *)malloc(num_switches * num_switches * sizeof(int));
>> +  if (!switch_bitmap)
>> +  {
>> +    osm_log(p_log, OSM_LOG_ERROR,
>> +            "lash_core: ERR 4D04: "
>> +            "Failed allocating switch_bitmap - out of memory\n");
>> +    goto Exit;
>> +  }
>>  
>>    for(i=0; i<num_switches; i++) {
>>      
>> @@ -1006,7 +1013,7 @@ static int lash_core(lash_t *p_lash)
>>     
>>      for(j=0; j<num_switches; j++) {
>>        for(k=0; k<num_switches; k++) {
>> -	switch_bitmap[j][k] = 0;
>> +	switch_bitmap[j * num_switches + k] = 0;
>>        }
>>        switches[j]->used_channels = 0;
>>        switches[j]->q_state = UNQUEUED;
>> @@ -1015,7 +1022,7 @@ static int lash_core(lash_t *p_lash)
>>    
>>    for(i=0; i<num_switches; i++) {
>>      for(dest_switch=0; dest_switch<num_switches; dest_switch++)
>> -      if(dest_switch != i && switch_bitmap[i][dest_switch] == 0) {
>> +      if(dest_switch != i && switch_bitmap[i * num_switches + dest_switch] == 0) {
>>  	v_lane = 0;
>>  	stop = 0;
>>  	while(v_lane < lanes_needed && stop == 0) {
>> @@ -1078,8 +1085,8 @@ static int lash_core(lash_t *p_lash)
>>  	  p_lash->virtual_location[i][dest_switch][v_lane] = 1;
>>  	  p_lash->virtual_location[dest_switch][i][v_lane] = 1;
>>  
>> -	  switch_bitmap[i][dest_switch] = 1;
>> -	  switch_bitmap[dest_switch][i] = 1;
>> +	  switch_bitmap[i * num_switches + dest_switch] = 1;
>> +	  switch_bitmap[dest_switch * num_switches + i] = 1;
>>  	}
>>  
>>        for(j=0; j<num_switches; j++) {
>> @@ -1115,6 +1122,8 @@ static int lash_core(lash_t *p_lash)
>>  	  "Lane requirements (%d) exceed available lanes (%d)\n",
>>  	  p_lash->vl_min, lanes_needed);
>>   Exit:
>> +  if (switch_bitmap)
>> +    free(switch_bitmap);
>>    OSM_LOG_EXIT(p_log);
>>    return status;
>>  }
>