mir/openvswitch
2
0
Fork 0
mirror of https://github.com/openvswitch/ovs synced 2025-10-15 14:17:18 +00:00
Code Issues Releases Wiki Activity

flow: Make size of flow struct a multiple of 8.

Browse Source 
The compiler wants to pad structures to a multiple of the native
datatype for the architecture, so a multiple of 4 on 32-bit platforms
and a multiple of 8 on 64-bit.  Currently the size struct flow is
a multiple of 4, so the total size with padding varies depending on
the architecture, causing build asserts to fail.  This explicitly pads
it out to a multiple of 8 for consistency.
This commit is contained in:
Jesse Gross
2010-12-11 17:31:36 -08:00
parent 40796b34ab
commit dd2cb550e5
1 changed files with 2 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
lib/flow.h
View File

@@ -49,12 +49,13 @@ struct flow {
uint8_t dl_dst[6]; /* Ethernet destination address. */
uint8_t nw_proto; /* IP protocol or low 8 bits of ARP opcode. */
uint8_t nw_tos; /* IP ToS (DSCP field, 6 bits). */
uint32_t reserved; /* Reserved for 64-bit packing. */
};
/* Assert that there are FLOW_SIG_SIZE bytes of significant data in "struct
* flow", followed by FLOW_PAD_SIZE bytes of padding. */
#define FLOW_SIG_SIZE (40 + FLOW_N_REGS * 4)
#define FLOW_PAD_SIZE 0
#define FLOW_PAD_SIZE 4
BUILD_ASSERT_DECL(offsetof(struct flow, nw_tos) == FLOW_SIG_SIZE - 1);
BUILD_ASSERT_DECL(sizeof(((struct flow *)0)->nw_tos) == 1);
BUILD_ASSERT_DECL(sizeof(struct flow) == FLOW_SIG_SIZE + FLOW_PAD_SIZE);