Few targets need more than just pending IRQ set. They include some flags to be
set that are checked in IRQ handler. This is the case for targets in this
commit.
Before this patch, when calling lfs_mkdir or lfs_file_open with root
as the target, littlefs wouldn't find the path properly and happily
run into undefined behaviour.
The fix is to populate a directory entry for root in the lfs_dir_find
function. As an added plus, this allowed several special cases around
root to be completely dropped.
sleep_manager_racecondition test fix for devices with low CPU clock
This RP contains fix for sleep_manager_racecondition test
for very slow devices (like NRF51). It fixes the test itself
as well as side effects of fix introduced in
#5046 (us ticker: fix fire interrupt handling)
The idea of the test was to test race condition between main thread
and interrupt handler calling the same function.
To efficiently test this, each handler call should interrupt
main thread to make race more likely.
On very slow devices (like NRF51) when we set very low ticker period
(e.g less then 1000us for NRF51) there is no much time for thread scheduling.
On such slow devices, setting period to 500 us cause that
main thread is scheduled very rarely and only handler is
constantly called making test unreliable.
Fix introduced in #5046 (us ticker: fix fire interrupt handling)
changed fire_interrupt function implementation causing more
interrupt tailing thus even less time for main thread scheduling.
After introduction of #5046 (us ticker: fix fire interrupt handling)
when running sleep_manager_racecondition test on NRF51
(with ticker1.attach_us(&sleep_manager_locking_irq_test, 500);)
test is failing with timeout due to the fact that interrupt
handler is constantly called and main thread is never scheduled.
Current behaviour ends up undefined when the constructor leaves early.
Now FilePath just discards leading slashes and otherwise asserts if the
path is bad.
How you write and ersae the flash on the NRF52 changes depending on
whether the SoftDevice is enabled or not.
This change does a runtime check before erasing and writing, and
then chooses the correct function to perform the action.
Rather than tracking all in-flight blocks blocks during a lookahead,
littlefs uses an ack scheme to mark the first allocated block that
hasn't reached the disk yet. littlefs assumes all blocks since the
last ack are bad or in-flight, and uses this to know when it's out
of storage.
However, these unacked allocations were still being populated in the
lookahead buffer. If the whole block device fits in the lookahead
buffer, _and_ littlefs managed to scan around the whole storage while
an unacked block was still in-flight, it would assume the block was
free and misallocate it.
The fix is to only fill the lookahead buffer up to the last ack.
The internal free structure was restructured to simplify the runtime
calculation of lookahead size.
Delta calculation from lp_ticker_set_interrupt() function:
delta_us = timestamp > now_us ? timestamp - now_us : (uint32_t)((uint64_t)timestamp + 0xFFFFFFFF - now_us);
Lets assume that timestam == now_us.
Expected delta value should be 0 and in this current version is 0xFFFFFFFF.
The following condition:
timestamp > now_us
should have the following form:
timestamp >= now_us
Additionally modified us ticker driver to provide the same logic.