Attachment 1630037 Details for Bug 1765547 – Test program to demonstrate the issue (under MIT license)

Test program to demonstrate the issue (under MIT license)

parallel-falloc-and-pwrite.c (text/x-csrc), 2.92 KB, created by Hanna Czenczek on 2019-10-29 07:33:41 UTC

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Creator: Hanna Czenczek

Created: 2019-10-29 07:33:41 UTC

Size: 2.92 KB

patch

obsolete

>/*
> * Test for concurrent fallocate() and AIO pwrite, where both are beyond the
> * EOF and the pwrite area lies after the fallocate() area
> *
> * Copyright (c) 2019 Max Reitz
> *
> * Permission is hereby granted, free of charge, to any person obtaining a copy
> * of this software and associated documentation files (the "Software"), to deal
> * in the Software without restriction, including without limitation the rights
> * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> * copies of the Software, and to permit persons to whom the Software is
> * furnished to do so, subject to the following conditions:
> * 
> * The above copyright notice and this permission notice shall be included in all
> * copies or substantial portions of the Software.
> * 
> * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> * SOFTWARE.
> */
>
>
>#define _GNU_SOURCE
>
>#include <assert.h>
>#include <fcntl.h>
>#include <libaio.h>
>#include <pthread.h>
>#include <stdio.h>
>#include <stdlib.h>
>#include <string.h>
>#include <unistd.h>
>
>// Define this to perform the fallocate and the pwrite sequentially
>// instead of in parallel
>
>// #define IN_ORDER
>
>
>int fd;
>
>void *falloc_thread(void *arg)
>{
>    int ret;
>
>    (void)arg;
>
>    puts("starting fallocate");
>
>    ret = fallocate(fd, 0, 0, 4096);
>    assert(ret == 0);
>
>    puts("fallocate done");
>
>    return NULL;
>}
>
>int main(int argc, char *argv[])
>{
>    pthread_t falloc_thr;
>    int ret;
>
>    if (argc != 2) {
>        fprintf(stderr, "Usage: %s <scratch file>\n", argv[0]);
>        return 1;
>    }
>
>    fd = open(argv[1], O_CREAT | O_RDWR | O_TRUNC | O_DIRECT, 0666);
>    assert(fd >= 0);
>
>    void *buf = aligned_alloc(4096, 4096);
>    memset(buf, 42, 4096);
>
>    io_context_t ctx = 0;
>    ret = io_setup(1, &ctx);
>    assert(ret == 0);
>
>    ret = pthread_create(&falloc_thr, NULL, &falloc_thread, NULL);
>    assert(ret == 0);
>
>#ifdef IN_ORDER
>    ret = pthread_join(falloc_thr, NULL);
>    assert(ret == 0);
>#endif
>
>    struct iocb ior;
>    io_prep_pwrite(&ior, fd, buf, 4096, 4096);
>
>    puts("submitting pwrite");
>
>    struct iocb *ios[] = { &ior };
>    ret = io_submit(ctx, 1, ios);
>    assert(ret == 1);
>
>    struct io_event evs[1];
>    ret = io_getevents(ctx, 1, 1, evs, NULL);
>    assert(ret == 1);
>
>    puts("pwrite done");
>
>#ifndef IN_ORDER
>    ret = pthread_join(falloc_thr, NULL);
>    assert(ret == 0);
>#endif
>
>    ret = io_destroy(ctx);
>    assert(ret == 0);
>
>    close(fd);
>    free(buf);
>
>    puts("\nHexdump should show 4k of 0s and 4k of 42s:\n");
>
>    execlp("hexdump", "hexdump", "-C", argv[1], NULL);
>    return 1;
>}

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Attachments on bug 1765547: 1629144 | 1630037