Skip to content

Reduce FS caching #20

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Closed
tannewt opened this issue Oct 17, 2016 · 0 comments
Closed

Reduce FS caching #20

tannewt opened this issue Oct 17, 2016 · 0 comments
Labels
enhancement

Comments

@tannewt
Copy link
Member

tannewt commented Oct 17, 2016

Make sure that MicroPython can access a file after you flush or eject a mass storage device without a board reset.
jepler pushed a commit that referenced this issue Sep 16, 2020
@DavePutz
Merge pull request #20 from adafruit/main
d7eedc5 
Update from main
jepler added a commit to jepler/circuitpython that referenced this issue Oct 3, 2020
@jepler
Update protomatter
1cdc91d 
This brings in the following, and updates us to the 1.0.4 release tag:

Submodule lib/protomatter 2a1ba8fa4..5f07ec618:
  > Bumping version for release
  > Merge pull request adafruit#21 from makermelissa/master
  > Merge pull request adafruit#20 from makermelissa/master
  > Merge pull request adafruit#18 from jepler/fix-cpy-3184
  > Merge pull request adafruit#14 from hierophect/cpy-timer-allocator

We previously had the _changes_ of jepler/fix-cpy-3184 and
hierophect/cpy-timer-allocator but not their merge commits.

The only other changes in protomatter were one formatting change in the
core, plus several Arduino sketches.  So this should make no practical
difference for CPy.
@jepler jepler mentioned this issue Oct 3, 2020
Merged
cwalther pushed a commit to cwalther/circuitpython that referenced this issue Jun 1, 2024
@neuschaefer @dpgeorge
py/nlrthumb: Make non-Thumb2 long-jump workaround opt-in.
7b050b3 
Although the original motivation given for the workaround[1] is correct,
nlr.o and nlrthumb.o are linked with a small enough distance that the
problem does not occur, and the workaround isn't necessary. The distance
between the b instruction and its target (nlr_push_tail) is just 64
bytes[2], well within the ±2046 byte range addressable by an
unconditional branch instruction in Thumb mode.

The workaround induces a relocation in the text section (textrel), which
isn't supported everywhere, notably not on musl-libc[3], where it causes
a crash on start-up. With the workaround removed, micropython works on an
ARMv5T Linux system built with musl-libc.

This commit changes nlrthumb.c to use a direct jump by default, but
leaves the long jump workaround as an option for those cases where it's
actually needed.

[1]: commit dd376a2

Author: Damien George <[email protected]>
Date:   Fri Sep 1 15:25:29 2017 +1000

    py/nlrthumb: Get working again on standard Thumb arch (ie not Thumb2).

    "b" on Thumb might not be long enough for the jump to nlr_push_tail so
    it must be done indirectly.

[2]: Excerpt from objdump -d micropython:

000095c4 <nlr_push_tail>:
    95c4:       b510            push    {r4, lr}
    95c6:       0004            movs    r4, r0
    95c8:       f02d fd42       bl      37050 <mp_thread_get_state>
    95cc:       6943            ldr     r3, [r0, adafruit#20]
    95ce:       6023            str     r3, [r4, #0]
    95d0:       6144            str     r4, [r0, adafruit#20]
    95d2:       2000            movs    r0, #0
    95d4:       bd10            pop     {r4, pc}

000095d6 <nlr_pop>:
    95d6:       b510            push    {r4, lr}
    95d8:       f02d fd3a       bl      37050 <mp_thread_get_state>
    95dc:       6943            ldr     r3, [r0, adafruit#20]
    95de:       681b            ldr     r3, [r3, #0]
    95e0:       6143            str     r3, [r0, adafruit#20]
    95e2:       bd10            pop     {r4, pc}

000095e4 <nlr_push>:
    95e4:       60c4            str     r4, [r0, adafruit#12]
    95e6:       6105            str     r5, [r0, adafruit#16]
    95e8:       6146            str     r6, [r0, adafruit#20]
    95ea:       6187            str     r7, [r0, adafruit#24]
    95ec:       4641            mov     r1, r8
    95ee:       61c1            str     r1, [r0, adafruit#28]
    95f0:       4649            mov     r1, r9
    95f2:       6201            str     r1, [r0, adafruit#32]
    95f4:       4651            mov     r1, sl
    95f6:       6241            str     r1, [r0, adafruit#36]   @ 0x24
    95f8:       4659            mov     r1, fp
    95fa:       6281            str     r1, [r0, adafruit#40]   @ 0x28
    95fc:       4669            mov     r1, sp
    95fe:       62c1            str     r1, [r0, adafruit#44]   @ 0x2c
    9600:       4671            mov     r1, lr
    9602:       6081            str     r1, [r0, adafruit#8]
    9604:       e7de            b.n     95c4 <nlr_push_tail>

[3]: https://www.openwall.com/lists/musl/2020/09/25/4

Signed-off-by: J. Neuschäfer <[email protected]>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
enhancement
Projects
None yet
Milestone
No milestone
Development

No branches or pull requests
1 participant
@tannewt