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diff --git a/sys/dev/hwpmc/hwpmc_mod.c b/sys/dev/hwpmc/hwpmc_mod.c
--- a/sys/dev/hwpmc/hwpmc_mod.c
+++ b/sys/dev/hwpmc/hwpmc_mod.c
@@ -241,6 +241,8 @@
static void pmc_process_allproc(struct pmc *pm);
static void pmc_process_csw_in(struct thread *td);
static void pmc_process_csw_out(struct thread *td);
+static void pmc_process_exec(struct thread *td,
+ struct pmckern_procexec *pk);
static void pmc_process_exit(void *arg, struct proc *p);
static void pmc_process_fork(void *arg, struct proc *p1,
struct proc *p2, int n);
@@ -1318,6 +1320,122 @@
return (0);
}
+/*
+ * Handle events after an exec() for a process:
+ * - Inform log owners of the new exec() event
+ * - Release any PMCs owned by the process before the exec()
+ * - Detach PMCs from the target if required
+ */
+static void
+pmc_process_exec(struct thread *td, struct pmckern_procexec *pk)
+{
+ struct pmc *pm;
+ struct pmc_owner *po;
+ struct pmc_process *pp;
+ struct proc *p;
+ char *fullpath, *freepath;
+ u_int ri;
+ bool is_using_hwpmcs;
+
+ sx_assert(&pmc_sx, SX_XLOCKED);
+
+ p = td->td_proc;
+ pmc_getfilename(p->p_textvp, &fullpath, &freepath);
+
+ PMC_EPOCH_ENTER();
+ /* Inform owners of SS mode PMCs of the exec event. */
+ CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) {
+ if ((po->po_flags & PMC_PO_OWNS_LOGFILE) != 0) {
+ pmclog_process_procexec(po, PMC_ID_INVALID, p->p_pid,
+ pk->pm_baseaddr, pk->pm_dynaddr, fullpath);
+ }
+ }
+ PMC_EPOCH_EXIT();
+
+ PROC_LOCK(p);
+ is_using_hwpmcs = (p->p_flag & P_HWPMC) != 0;
+ PROC_UNLOCK(p);
+
+ if (!is_using_hwpmcs) {
+ if (freepath != NULL)
+ free(freepath, M_TEMP);
+ return;
+ }
+
+ /*
+ * PMCs are not inherited across an exec(): remove any PMCs that this
+ * process is the owner of.
+ */
+ if ((po = pmc_find_owner_descriptor(p)) != NULL) {
+ pmc_remove_owner(po);
+ pmc_destroy_owner_descriptor(po);
+ }
+
+ /*
+ * If the process being exec'ed is not the target of any PMC, we are
+ * done.
+ */
+ if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) {
+ if (freepath != NULL)
+ free(freepath, M_TEMP);
+ return;
+ }
+
+ /*
+ * Log the exec event to all monitoring owners. Skip owners who have
+ * already received the event because they had system sampling PMCs
+ * active.
+ */
+ for (ri = 0; ri < md->pmd_npmc; ri++) {
+ if ((pm = pp->pp_pmcs[ri].pp_pmc) == NULL)
+ continue;
+
+ po = pm->pm_owner;
+ if (po->po_sscount == 0 &&
+ (po->po_flags & PMC_PO_OWNS_LOGFILE) != 0) {
+ pmclog_process_procexec(po, pm->pm_id, p->p_pid,
+ pk->pm_baseaddr, pk->pm_dynaddr, fullpath);
+ }
+ }
+
+ if (freepath != NULL)
+ free(freepath, M_TEMP);
+
+ PMCDBG4(PRC,EXC,1, "exec proc=%p (%d, %s) cred-changed=%d",
+ p, p->p_pid, p->p_comm, pk->pm_credentialschanged);
+
+ if (pk->pm_credentialschanged == 0) /* no change */
+ return;
+
+ /*
+ * If the newly exec()'ed process has a different credential
+ * than before, allow it to be the target of a PMC only if
+ * the PMC's owner has sufficient privilege.
+ */
+ for (ri = 0; ri < md->pmd_npmc; ri++) {
+ if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) {
+ if (pmc_can_attach(pm, td->td_proc) != 0) {
+ pmc_detach_one_process(td->td_proc, pm,
+ PMC_FLAG_NONE);
+ }
+ }
+ }
+
+ KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= md->pmd_npmc,
+ ("[pmc,%d] Illegal ref count %u on pp %p", __LINE__,
+ pp->pp_refcnt, pp));
+
+ /*
+ * If this process is no longer the target of any
+ * PMCs, we can remove the process entry and free
+ * up space.
+ */
+ if (pp->pp_refcnt == 0) {
+ pmc_remove_process_descriptor(pp);
+ pmc_destroy_process_descriptor(pp);
+ }
+}
+
/*
* Thread context switch IN.
*/
@@ -2045,119 +2163,9 @@
pmc_hooknames[function], arg);
switch (function) {
-
- /*
- * Process exec()
- */
case PMC_FN_PROCESS_EXEC:
- {
- char *fullpath, *freepath;
- unsigned int ri;
- int is_using_hwpmcs;
- struct pmc *pm;
- struct proc *p;
- struct pmc_owner *po;
- struct pmc_process *pp;
- struct pmckern_procexec *pk;
-
- sx_assert(&pmc_sx, SX_XLOCKED);
-
- p = td->td_proc;
- pmc_getfilename(p->p_textvp, &fullpath, &freepath);
-
- pk = (struct pmckern_procexec *) arg;
-
- PMC_EPOCH_ENTER();
- /* Inform owners of SS mode PMCs of the exec event. */
- CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext)
- if (po->po_flags & PMC_PO_OWNS_LOGFILE)
- pmclog_process_procexec(po, PMC_ID_INVALID,
- p->p_pid, pk->pm_baseaddr, pk->pm_dynaddr,
- fullpath);
- PMC_EPOCH_EXIT();
-
- PROC_LOCK(p);
- is_using_hwpmcs = p->p_flag & P_HWPMC;
- PROC_UNLOCK(p);
-
- if (!is_using_hwpmcs) {
- if (freepath)
- free(freepath, M_TEMP);
- break;
- }
-
- /*
- * PMCs are not inherited across an exec(): remove any
- * PMCs that this process is the owner of.
- */
-
- if ((po = pmc_find_owner_descriptor(p)) != NULL) {
- pmc_remove_owner(po);
- pmc_destroy_owner_descriptor(po);
- }
-
- /*
- * If the process being exec'ed is not the target of any
- * PMC, we are done.
- */
- if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) {
- if (freepath)
- free(freepath, M_TEMP);
- break;
- }
-
- /*
- * Log the exec event to all monitoring owners. Skip
- * owners who have already received the event because
- * they had system sampling PMCs active.
- */
- for (ri = 0; ri < md->pmd_npmc; ri++)
- if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) {
- po = pm->pm_owner;
- if (po->po_sscount == 0 &&
- po->po_flags & PMC_PO_OWNS_LOGFILE)
- pmclog_process_procexec(po, pm->pm_id,
- p->p_pid, pk->pm_baseaddr,
- pk->pm_dynaddr, fullpath);
- }
-
- if (freepath)
- free(freepath, M_TEMP);
-
-
- PMCDBG4(PRC,EXC,1, "exec proc=%p (%d, %s) cred-changed=%d",
- p, p->p_pid, p->p_comm, pk->pm_credentialschanged);
-
- if (pk->pm_credentialschanged == 0) /* no change */
- break;
-
- /*
- * If the newly exec()'ed process has a different credential
- * than before, allow it to be the target of a PMC only if
- * the PMC's owner has sufficient privilege.
- */
- for (ri = 0; ri < md->pmd_npmc; ri++)
- if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL)
- if (pmc_can_attach(pm, td->td_proc) != 0)
- pmc_detach_one_process(td->td_proc,
- pm, PMC_FLAG_NONE);
-
- KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= md->pmd_npmc,
- ("[pmc,%d] Illegal ref count %u on pp %p", __LINE__,
- pp->pp_refcnt, pp));
-
- /*
- * If this process is no longer the target of any
- * PMCs, we can remove the process entry and free
- * up space.
- */
- if (pp->pp_refcnt == 0) {
- pmc_remove_process_descriptor(pp);
- pmc_destroy_process_descriptor(pp);
- break;
- }
- }
- break;
+ pmc_process_exec(td, (struct pmckern_procexec *)arg);
+ break;
case PMC_FN_CSW_IN:
pmc_process_csw_in(td);

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