With shared memory mappings, once A and B both map the same memory address/file they see the same contents A [0xaaaaaaaa] - maps - to -> [0xAAAAAAAA] B [0xbbbbbbbb] - maps - to -> [0xAAAAAAAA] However, if A changes (update) the mappings to point to a different memory area/file offset, B sees different contents A [0xaaaaaaaa] - maps - to -> [0xBBBBBBBB] Is there a way to force update the mappings of B, so that B too sees contents at 0xBBBBBBBB? Could this be done, by deleting the shmem backing and making the fault handler update the mappings? On Mon, Jan 12, 2015 at 10:50 AM, <Valdis.Kletnieks@vt.edu> wrote:
On Mon, 12 Jan 2015 07:34:41 -0600, riya khanna said:
Suppose A and B have mapped the same physical memory or shmem file. I want a way to make process A forcefuly revoke/remap the existing shared memory mappings in process B, so that B sees whatever A does.
Umm..B should be seeing what A does *already*. That's the whole *point* of shared mmap spaces.
And what problem are you trying to solve by doing this, anyhow? There's probably a better approach (for starters, have A set up the mappings, then fork B which gets the mappings all set up from the start).