Re: [Qemu-devel] [PATCH v7 08/35] exec: allow memory to be allocated from any kind of path

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

On 02.11.2015 12:13, Xiao Guangrong wrote:
> Currently file_ram_alloc() is designed for hugetlbfs, however, the memory
> of nvdimm can come from either raw pmem device eg, /dev/pmem, or the file
> locates at DAX enabled filesystem
>
> So this patch let it work on any kind of path

No, this patch doesn't change any logic, but only fix variable name and 
some error messages.

>
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> ---
>   exec.c | 24 ++++++++++++------------
>   1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index 9de38be..9075f4d 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1184,25 +1184,25 @@ static void *file_ram_alloc(RAMBlock *block,
>       char *c;
>       void *area;
>       int fd;
> -    uint64_t hpagesize;
> +    uint64_t pagesize;
>       Error *local_err = NULL;
>   
> -    hpagesize = qemu_file_get_page_size(path, &local_err);
> +    pagesize = qemu_file_get_page_size(path, &local_err);
>       if (local_err) {
>           error_propagate(errp, local_err);
>           goto error;
>       }
>   
> -    if (hpagesize == getpagesize()) {
> -        fprintf(stderr, "Warning: path not on HugeTLBFS: %s\n", path);
> +    if (pagesize == getpagesize()) {
> +        fprintf(stderr, "Memory is not allocated from HugeTlbfs.\n");

Why do you remove path from error message? It is good additional 
information.. What if we have several memory file backends?

>       }
>   
> -    block->mr->align = hpagesize;
> +    block->mr->align = pagesize;
>   
> -    if (memory < hpagesize) {
> +    if (memory < pagesize) {
>           error_setg(errp, "memory size 0x" RAM_ADDR_FMT " must be equal to "
> -                   "or larger than huge page size 0x%" PRIx64,
> -                   memory, hpagesize);
> +                   "or larger than page size 0x%" PRIx64,
> +                   memory, pagesize);
>           goto error;
>       }
>   
> @@ -1226,14 +1226,14 @@ static void *file_ram_alloc(RAMBlock *block,
>       fd = mkstemp(filename);
>       if (fd < 0) {
>           error_setg_errno(errp, errno,
> -                         "unable to create backing store for hugepages");
> +                         "unable to create backing store for path %s", path);
>           g_free(filename);
>           goto error;
>       }
>       unlink(filename);
>       g_free(filename);
>   
> -    memory = ROUND_UP(memory, hpagesize);
> +    memory = ROUND_UP(memory, pagesize);
>   
>       /*
>        * ftruncate is not supported by hugetlbfs in older
> @@ -1245,10 +1245,10 @@ static void *file_ram_alloc(RAMBlock *block,
>           perror("ftruncate");
>       }
>   
> -    area = qemu_ram_mmap(fd, memory, hpagesize, block->flags & RAM_SHARED);
> +    area = qemu_ram_mmap(fd, memory, pagesize, block->flags & RAM_SHARED);
>       if (area == MAP_FAILED) {
>           error_setg_errno(errp, errno,
> -                         "unable to map backing store for hugepages");
> +                         "unable to map backing store for path %s", path);
>           close(fd);
>           goto error;
>       }
>

-- 
Best regards,
Vladimir
* now, @virtuozzo.com instead of @parallels.com. Sorry for this inconvenience.