[dpdk-dev] [PATCH v2 1/1] change hugepage sorting to avoid overlapping memcpy
Ralf Hoffmann
ralf.hoffmann at allegro-packets.com
Tue Jan 5 10:25:13 CET 2016
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 sort method to qsort to avoid this behavior, according to
original patch from Jay Rolette <rolette at infiniteio.com>. The separate
sort function is no longer necessary.
Signed-off-by: Ralf Hoffmann <ralf.hoffmann at allegro-packets.com>
---
v2:
* incorporate patch from http://dpdk.org/dev/patchwork/patch/2061/
to use qsort instead of bubble sort,
original patch by Jay Rolette <rolette at infiniteio.com>
lib/librte_eal/linuxapp/eal/eal_memory.c | 60 ++++++++------------------------
1 file changed, 14 insertions(+), 46 deletions(-)
diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
index 846fd31..a96d10a 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -701,54 +701,23 @@ error:
return -1;
}
-/*
- * Sort the hugepg_tbl by physical address (lower addresses first on x86,
- * 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
-sort_by_physaddr(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi)
+cmp_physaddr(const void *a, const void *b)
{
- unsigned i, j;
- int 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;
-
- /*
- * browse all entries starting at 'i', and find the
- * entry with the smallest addr
- */
- for (j=i; j< hpi->num_pages[0]; j++) {
-
- if (compare_addr == 0 ||
-#ifdef RTE_ARCH_PPC_64
- hugepg_tbl[j].physaddr > compare_addr) {
+#ifndef RTE_ARCH_PPC_64
+ const struct hugepage_file *p1 = (const struct hugepage_file *)a;
+ const struct hugepage_file *p2 = (const struct hugepage_file *)b;
#else
- hugepg_tbl[j].physaddr < compare_addr) {
+ /* PowerPC needs memory sorted in reverse order from x86 */
+ const struct hugepage_file *p1 = (const struct hugepage_file *)b;
+ const struct hugepage_file *p2 = (const struct hugepage_file *)a;
#endif
- compare_addr = hugepg_tbl[j].physaddr;
- compare_idx = j;
- }
- }
-
- /* should not happen */
- if (compare_idx == -1) {
- RTE_LOG(ERR, EAL, "%s(): error in physaddr sorting\n", __func__);
- return -1;
- }
-
- /* swap the 2 entries in the table */
- memcpy(&tmp, &hugepg_tbl[compare_idx],
- sizeof(struct hugepage_file));
- memcpy(&hugepg_tbl[compare_idx], &hugepg_tbl[i],
- sizeof(struct hugepage_file));
- memcpy(&hugepg_tbl[i], &tmp, sizeof(struct hugepage_file));
- }
- return 0;
+ if (p1->physaddr < p2->physaddr)
+ return -1;
+ else if (p1->physaddr > p2->physaddr)
+ return 1;
+ else
+ return 0;
}
/*
@@ -1195,8 +1164,7 @@ rte_eal_hugepage_init(void)
goto fail;
}
- if (sort_by_physaddr(&tmp_hp[hp_offset], hpi) < 0)
- goto fail;
+ qsort(&tmp_hp[hp_offset], hpi->num_pages[0], sizeof(struct hugepage_file), cmp_physaddr);
#ifdef RTE_EAL_SINGLE_FILE_SEGMENTS
/* remap all hugepages into single file segments */
--
2.5.0
More information about the dev
mailing list