https://dpdk.org/tracker/show_bug.cgi?id=18
Indicated that several mmap call sites in the linuxapp eal code used an
fd that was not -1 in their calls while using MAP_ANONYMOUS. While
probably not a huge deal, the man page does say the fd should be -1 for
portability, as some implementations don't ignore fd as they should for
MAP_ANONYMOUS, and seting -1 here allows us to eliminate some code.
Signed-off-by: Neil Horman <nhor...@tuxdriver.com>
CC: Thomas Monjalon <tho...@monjalon.net>
CC: Ferruh Yigit <ferruh.yi...@intel.com>
---
lib/librte_eal/linuxapp/eal/eal_memory.c | 32 +++++++-------------------------
1 file changed, 7 insertions(+), 25 deletions(-)
diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c
b/lib/librte_eal/linuxapp/eal/eal_memory.c
index 38853b753..acb553243 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -222,7 +222,7 @@ aslr_enabled(void)
}
/*
- * Try to mmap *size bytes in /dev/zero. If it is successful, return the
+ * Try to mmap *size bytes. If it is successful, return the
* pointer to the mmap'd area and keep *size unmodified. Else, retry
* with a smaller zone: decrease *size by hugepage_sz until it reaches
* 0. In this case, return NULL. Note: this function returns an address
@@ -233,7 +233,6 @@ get_virtual_area(size_t *size, size_t hugepage_sz)
{
void *addr;
void *addr_hint;
- int fd;
long aligned_addr;
if (internal_config.base_virtaddr != 0) {
@@ -248,11 +247,6 @@ get_virtual_area(size_t *size, size_t hugepage_sz)
RTE_LOG(DEBUG, EAL, "Ask a virtual area of 0x%zx bytes\n", *size);
- fd = open("/dev/zero", O_RDONLY);
- if (fd < 0){
- RTE_LOG(ERR, EAL, "Cannot open /dev/zero\n");
- return NULL;
- }
do {
addr = mmap(addr_hint, (*size) + hugepage_sz, PROT_READ,
#ifdef RTE_ARCH_PPC_64
@@ -260,7 +254,7 @@ get_virtual_area(size_t *size, size_t hugepage_sz)
#else
MAP_PRIVATE,
#endif
- fd, 0);
+ -1, 0);
if (addr == MAP_FAILED) {
*size -= hugepage_sz;
} else if (addr_hint != NULL && addr != addr_hint) {
@@ -273,14 +267,12 @@ get_virtual_area(size_t *size, size_t hugepage_sz)
} while (addr == MAP_FAILED && *size > 0);
if (addr == MAP_FAILED) {
- close(fd);
RTE_LOG(ERR, EAL, "Cannot get a virtual area: %s\n",
strerror(errno));
return NULL;
}
munmap(addr, (*size) + hugepage_sz);
- close(fd);
/* align addr to a huge page size boundary */
aligned_addr = (long)addr;
@@ -1011,7 +1003,7 @@ rte_eal_hugepage_init(void)
/* hugetlbfs can be disabled */
if (internal_config.no_hugetlbfs) {
addr = mmap(NULL, internal_config.memory, PROT_READ |
PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (addr == MAP_FAILED) {
RTE_LOG(ERR, EAL, "%s: mmap() failed: %s\n", __func__,
strerror(errno));
@@ -1339,7 +1331,7 @@ rte_eal_hugepage_attach(void)
unsigned i, s = 0; /* s used to track the segment number */
unsigned max_seg = RTE_MAX_MEMSEG;
off_t size = 0;
- int fd, fd_zero = -1, fd_hugepage = -1;
+ int fd, fd_hugepage = -1;
if (aslr_enabled() > 0) {
RTE_LOG(WARNING, EAL, "WARNING: Address Space Layout
Randomization "
@@ -1350,11 +1342,6 @@ rte_eal_hugepage_attach(void)
test_phys_addrs_available();
- fd_zero = open("/dev/zero", O_RDONLY);
- if (fd_zero < 0) {
- RTE_LOG(ERR, EAL, "Could not open /dev/zero\n");
- goto error;
- }
fd_hugepage = open(eal_hugepage_info_path(), O_RDONLY);
if (fd_hugepage < 0) {
RTE_LOG(ERR, EAL, "Could not open %s\n",
eal_hugepage_info_path());
@@ -1373,8 +1360,6 @@ rte_eal_hugepage_attach(void)
break;
/*
- * fdzero is mmapped to get a contiguous block of virtual
- * addresses of the appropriate memseg size.
* use mmap to get identical addresses as the primary process.
*/
base_addr = mmap(mcfg->memseg[s].addr, mcfg->memseg[s].len,
@@ -1384,21 +1369,21 @@ rte_eal_hugepage_attach(void)
#else
MAP_PRIVATE,
#endif
- fd_zero, 0);
+ -1, 0);
if (base_addr == MAP_FAILED ||
base_addr != mcfg->memseg[s].addr) {
max_seg = s;
if (base_addr != MAP_FAILED) {
/* errno is stale, don't use */
RTE_LOG(ERR, EAL, "Could not mmap %llu bytes "
- "in /dev/zero at [%p], got [%p] - "
+ "at [%p], got [%p] - "
"please use '--base-virtaddr' option\n",
(unsigned long long)mcfg->memseg[s].len,
mcfg->memseg[s].addr, base_addr);
munmap(base_addr, mcfg->memseg[s].len);
} else {
RTE_LOG(ERR, EAL, "Could not mmap %llu bytes "
- "in /dev/zero at [%p]: '%s'\n",
+ "at [%p]: '%s'\n",
(unsigned long long)mcfg->memseg[s].len,
mcfg->memseg[s].addr, strerror(errno));
}
@@ -1465,7 +1450,6 @@ rte_eal_hugepage_attach(void)
}
/* unmap the hugepage config file, since we are done using it */
munmap(hp, size);
- close(fd_zero);
close(fd_hugepage);
return 0;
@@ -1474,8 +1458,6 @@ rte_eal_hugepage_attach(void)
munmap(mcfg->memseg[i].addr, mcfg->memseg[i].len);
if (hp != NULL && hp != MAP_FAILED)
munmap(hp, size);
- if (fd_zero >= 0)
- close(fd_zero);
if (fd_hugepage >= 0)
close(fd_hugepage);
return -1;
--
2.14.3
