[IA64] fix perfmon context load

The PFM_LOAD_CONTEXT may fail silently and cause a session
to remain reserved even though it should not. This can happen
when the commands succeeds in reserving the session but fails
when it actually tries to attach to the load_pid. In that case,
the command has failed but will return 0. More importantly,
the session will remain reserved. This patch fixes the problem.

Signed-off-by: <stephane.eranian@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This commit is contained in:
stephane.eranian@hp.com 2005-07-28 05:18:00 -07:00 committed by Tony Luck
parent bc68552faa
commit 6bf11e8c70
1 changed files with 1 additions and 0 deletions

View File

@ -4312,6 +4312,7 @@ pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
DPRINT(("before cmpxchg() old_ctx=%p new_ctx=%p\n",
thread->pfm_context, ctx));
ret = -EBUSY;
old = ia64_cmpxchg(acq, &thread->pfm_context, NULL, ctx, sizeof(pfm_context_t *));
if (old != NULL) {
DPRINT(("load_pid [%d] already has a context\n", req->load_pid));