MFC r273236:

Use pmc_destroy_pmc_descriptor() to actually free the pmc, which is
consistent with pmc_destroy_owner_descriptor(). Also be sure to destroy
PMCs if a process exits or execs without explicitly releasing them.

1 files changed, 9 insertions, 13 deletions

diff --git a/sys/dev/hwpmc/hwpmc_mod.c b/sys/dev/hwpmc/hwpmc_mod.c
index 8e5eac8..77cd257 100644
--- a/sys/dev/hwpmc/hwpmc_mod.c
+++ b/sys/dev/hwpmc/hwpmc_mod.c
@@ -192,6 +192,7 @@ static int	pmc_detach_process(struct proc *p, struct pmc *pm);
 static int	pmc_detach_one_process(struct proc *p, struct pmc *pm,
     int flags);
 static void	pmc_destroy_owner_descriptor(struct pmc_owner *po);
+static void	pmc_destroy_pmc_descriptor(struct pmc *pm);
 static struct pmc_owner *pmc_find_owner_descriptor(struct proc *p);
 static int	pmc_find_pmc(pmc_id_t pmcid, struct pmc **pm);
 static struct pmc *pmc_find_pmc_descriptor_in_process(struct pmc_owner *po,
@@ -753,6 +754,7 @@ pmc_remove_owner(struct pmc_owner *po)
 		    ("[pmc,%d] owner %p != po %p", __LINE__, pm->pm_owner, po));
 
 		pmc_release_pmc_descriptor(pm);	/* will unlink from the list */
+		pmc_destroy_pmc_descriptor(pm);
 	}
 
 	KASSERT(po->po_sscount == 0,
@@ -2165,9 +2167,7 @@ pmc_allocate_pmc_descriptor(void)
 static void
 pmc_destroy_pmc_descriptor(struct pmc *pm)
 {
-	(void) pm;
 
-#ifdef	DEBUG
 	KASSERT(pm->pm_state == PMC_STATE_DELETED ||
 	    pm->pm_state == PMC_STATE_FREE,
 	    ("[pmc,%d] destroying non-deleted PMC", __LINE__));
@@ -2178,7 +2178,8 @@ pmc_destroy_pmc_descriptor(struct pmc *pm)
 	KASSERT(pm->pm_runcount == 0,
 	    ("[pmc,%d] pmc has non-zero run count %d", __LINE__,
 		pm->pm_runcount));
-#endif
+
+	free(pm, M_PMC);
 }
 
 static void
@@ -2211,10 +2212,10 @@ pmc_wait_for_pmc_idle(struct pmc *pm)
  *  - detaches the PMC from hardware
  *  - unlinks all target threads that were attached to it
  *  - removes the PMC from its owner's list
- *  - destroy's the PMC private mutex
+ *  - destroys the PMC private mutex
  *
- * Once this function completes, the given pmc pointer can be safely
- * FREE'd by the caller.
+ * Once this function completes, the given pmc pointer can be freed by
+ * calling pmc_destroy_pmc_descriptor().
  */
 
 static void
@@ -2364,8 +2365,6 @@ pmc_release_pmc_descriptor(struct pmc *pm)
 		LIST_REMOVE(pm, pm_next);
 		pm->pm_owner = NULL;
 	}
-
-	pmc_destroy_pmc_descriptor(pm);
 }
 
 /*
@@ -3372,7 +3371,6 @@ pmc_syscall_handler(struct thread *td, void *syscall_args)
 
 		if (n == (int) md->pmd_npmc) {
 			pmc_destroy_pmc_descriptor(pmc);
-			free(pmc, M_PMC);
 			pmc = NULL;
 			error = EINVAL;
 			break;
@@ -3408,7 +3406,6 @@ pmc_syscall_handler(struct thread *td, void *syscall_args)
 			    (error = pcd->pcd_config_pmc(cpu, adjri, pmc)) != 0) {
 				(void) pcd->pcd_release_pmc(cpu, adjri, pmc);
 				pmc_destroy_pmc_descriptor(pmc);
-				free(pmc, M_PMC);
 				pmc = NULL;
 				pmc_restore_cpu_binding(&pb);
 				error = EPERM;
@@ -3436,7 +3433,7 @@ pmc_syscall_handler(struct thread *td, void *syscall_args)
 		if ((error =
 		    pmc_register_owner(curthread->td_proc, pmc)) != 0) {
 			pmc_release_pmc_descriptor(pmc);
-			free(pmc, M_PMC);
+			pmc_destroy_pmc_descriptor(pmc);
 			pmc = NULL;
 			break;
 		}
@@ -3679,8 +3676,7 @@ pmc_syscall_handler(struct thread *td, void *syscall_args)
 		po = pm->pm_owner;
 		pmc_release_pmc_descriptor(pm);
 		pmc_maybe_remove_owner(po);
-
-		free(pm, M_PMC);
+		pmc_destroy_pmc_descriptor(pm);
 	}
 	break;