A fix for message: [ x ] alloc_contig_range: [y, z) PFNs busy

I get a lot of the messages specified in the title when storing a file at a particular point in the program. Sometimes they are followed by x callbacks suppressed . Identical program running on iMX6ULL 512MB IT V1.0A does not do it. Researching it on the internet it seems to be something that many have encountered in various versions and implementations of Linux and various platforms, so not exclusive to Toradex. Many talk about patches and the need to get it fixed. Is Toradex doing something about it? Although at this point it does not affect the performance of my program, I suspect at some point it might, and it does not seem right in any case. Please provide some help. Thanks.

hi @gwpolo

Which carrier board are you using?

I get a lot of the messages specified in the title when storing a file at a particular point in the program.

How are you storing the fie?
Could you provide a sample code?

Thanks and best regards,
Jaski

Hi jaski,
I am using the Iris carrier board. I should note that I have 2 systems built with essentially identical code. The first one has iMXULL 512MB IT V1.0A and it does NOT do this. The second one, with V1.1A does. Your tech support suggested changing the level of the console log to 5. I did that and the PFNs busy messages disappeared, but the x callbacks suppressed did not. Further reducing the level to 4, both disappeared, but I am not sure how safe that is. Also, changing that level seems to be temporary, until the next power cycle. Here are the few lines of code showing how I store the file:

FILE * fp1;
fp1=fopen(PT_data_ptr, "a+");
sprintf(gallons, "Y%s %s %.2f %s",Yard,UnitID,gal_cnt,TimeStamp);
fputs(gallons,fp1);
fclose(fp1);

hi @gwpolo

Thanks for your Input and your code.

Are you running also the same Bsp on the two devices?

Honestly I don’t know how to check that.

Could you post a results of uname -a command for each module?

Hi. Honestly, I have no idea how to determine what BSP I am running on each board. Can you tell me how to check it?

Hi Jaski,
Here is the information on the BSP:
Board that does NOT have a problem: 2.8b4.129 2018-10-05
Board that HAS the problem: 2.8b6.184 2019-04-01

I hope this helps me get to the bottom of this.

HI @gwpolo

Thanks for your Input. Bsp 2.8b6.184 2019-04-01 is the latest Bsp and which is still supported. We will look into this issue and will come back to you .

Best regards,
Jaski

hi @gwpolo:

I tried to reproduce the issue but I was not able to. Could you tell me, what application is running on the module?

Share the complete code if possible?

Best regards,
Jaski