Hi Ralf,
Just a few comments/suggestions:
Add 'eal/linux:' to the commit title, ie:
"eal/linux: change hugepage sorting to avoid overlapping memcpy"
On 04/09/2015 11:14, Ralf Hoffmann wrote:
> with only one hugepage or already sorted hugepage addresses, the sort
> function called memcpy with same src and dst pointer. Debugging with
> valgrind will issue a warning about overlapping area. This patch changes
> the bubble sort to avoid this behavior. Also, the function cannot fail
> any longer.
>
> Signed-off-by: Ralf Hoffmann <ralf.hoffmann at allegro-packets.com>
> ---
> lib/librte_eal/linuxapp/eal/eal_memory.c | 27 +++++++++++++--------------
> 1 file changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c
> b/lib/librte_eal/linuxapp/eal/eal_memory.c
> index ac2745e..6d01f61 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_memory.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
> @@ -699,25 +699,25 @@ error:
> * higher address first on powerpc). We use a slow algorithm, but we won't
> * have millions of pages, and this is only done at init time.
> */
> -static int
> +static void
> sort_by_physaddr(struct hugepage_file *hugepg_tbl, struct hugepage_info
> *hpi)
> {
> unsigned i, j;
> - int compare_idx;
> + unsigned compare_idx;
> uint64_t compare_addr;
> struct hugepage_file tmp;
>
> for (i = 0; i < hpi->num_pages[0]; i++) {
> - compare_addr = 0;
> - compare_idx = -1;
> + compare_addr = hugepg_tbl[i].physaddr;
> + compare_idx = i;
>
> /*
> - * browse all entries starting at 'i', and find the
> + * browse all entries starting at 'i+1', and find the
> * entry with the smallest addr
> */
> - for (j=i; j< hpi->num_pages[0]; j++) {
> + for (j=i + 1; j < hpi->num_pages[0]; j++) {
Although there are many style/checkpatch issues in current code, we try
to fix them
in new patches.
In that regard, checkpatch complains about above line with:
ERROR:SPACING: spaces required around that '='
>
> - if (compare_addr == 0 ||
> + if (
> #ifdef RTE_ARCH_PPC_64
> hugepg_tbl[j].physaddr > compare_addr) {
> #else
> @@ -728,10 +728,9 @@ sort_by_physaddr(struct hugepage_file *hugepg_tbl,
> struct hugepage_info *hpi)
> }
> }
>
> - /* should not happen */
> - if (compare_idx == -1) {
> - RTE_LOG(ERR, EAL, "%s(): error in physaddr sorting\n",
> __func__);
> - return -1;
> + if (compare_idx == i) {
> + /* no smaller page found */
> + continue;
> }
>
> /* swap the 2 entries in the table */
> @@ -741,7 +740,8 @@ sort_by_physaddr(struct hugepage_file *hugepg_tbl, struct
> hugepage_info *hpi)
> sizeof(struct hugepage_file));
> memcpy(&hugepg_tbl[i], &tmp, sizeof(struct hugepage_file));
> }
> - return 0;
> +
> + return;
> }
I reckon checkpatch is not picking this one because the end-of-function
is not part of the patch,
but it is a warning:
WARNING:RETURN_VOID: void function return statements are not generally
useful
>
> /*
> @@ -1164,8 +1164,7 @@ rte_eal_hugepage_init(void)
> goto fail;
> }
>
> - if (sort_by_physaddr(&tmp_hp[hp_offset], hpi) < 0)
> - goto fail;
> + sort_by_physaddr(&tmp_hp[hp_offset], hpi);
>
> #ifdef RTE_EAL_SINGLE_FILE_SEGMENTS
> /* remap all hugepages into single file segments */
>
>
Thanks,
Sergio
