On Tue, 24 Nov 2015 06:30:22 +0000, Ramon Fried said:
I'm currently debugging a ISP DMA issue in a kernel module. For debugging, I would like to dump buffers to a file on run time. The buffers are quite big, 1MB at least.
The *other* question is how *often* you plan to do this. Doing it once a second is one thing, doing it once a millisecond is another.
I can think of numerous ways of transferring the buffer to user space and saving it by a dedicated user process (Netlink, sysfs, char device, etc.)
sysfs is probably a bad choice due to its 'one attribute per file' rule, debugfs would be a better approach. netlink is probably an option, and it's hard to argue with the simplicity of a char device with a plain old 'tail -f /dev/my-debug-file > /tmp/debug.out' or similar...