[LTP] [PATCH] increasing buffer size for correct alignment

[Han Pingtian <hanpt@linux.vnet.ibm.com>]

Hey there,

I have a patch for aio-stress to align buffer address correctly. Please
have a look. Thanks in advance.

For align buffer address to the number specified by -a option in
aio-stress, it needs to add page_size_mask extra length to total_ram
before call allocation functions. Or it wouldn't be correct in this line
after the allocation:

         p = (char *)((intptr_t) (p + page_size_mask) & ~page_size_mask);

Signed-off-by: Han Pingtian <hanpt@linux.vnet.ibm.com>
---
 testcases/kernel/io/ltp-aiodio/aio-stress.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/testcases/kernel/io/ltp-aiodio/aio-stress.c b/testcases/kernel/io/ltp-aiodio/aio-stress.c
index 0b7148c..24675ec 100644
--- a/testcases/kernel/io/ltp-aiodio/aio-stress.c
+++ b/testcases/kernel/io/ltp-aiodio/aio-stress.c
@@ -1022,7 +1022,7 @@ int setup_shared_mem(int num_threads, int num_files, int depth,
 	if (use_shm == USE_MALLOC) {
 		p = malloc(total_ram + page_size_mask);
 	} else if (use_shm == USE_SHM) {
-		shm_id = shmget(IPC_PRIVATE, total_ram, IPC_CREAT | 0700);
+		shm_id = shmget(IPC_PRIVATE, total_ram + page_size_mask, IPC_CREAT | 0700);
 		if (shm_id < 0) {
 			perror("shmget");
 			drop_shm();
@@ -1046,9 +1046,9 @@ int setup_shared_mem(int num_threads, int num_files, int depth,
 			goto free_buffers;
 		}
 		unlink(mmap_name);
-		ftruncate(fd, total_ram);
+		ftruncate(fd, total_ram + page_size_mask);
 		shm_id = fd;
-		p = mmap((char *)0x50000000, total_ram,
+		p = mmap((char *)0x50000000, total_ram + page_size_mask,
 			 PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 
 		if (p == MAP_FAILED) {
-- 
1.9.3


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