MFP4:

- Implement sampling modes and logging support in hwpmc(4).

- Separate MI and MD parts of hwpmc(4) and allow sharing of
  PMC implementations across different architectures.
  Add support for P4 (EMT64) style PMCs to the amd64 code.

- New pmcstat(8) options: -E (exit time counts) -W (counts
  every context switch), -R (print log file).

- pmc(3) API changes, improve our ability to keep ABI compatibility
  in the future.  Add more 'alias' names for commonly used events.

- bug fixes & documentation.

1 files changed, 3 insertions, 2 deletions

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 78d86ce..2a4c9ab 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -670,14 +670,15 @@ interpret:
 
 #ifdef	HWPMC_HOOKS
 	/*
-	 * Check if the process is using PMCs and if so do exec() time
+	 * Check if system-wide sampling is in effect or if the
+	 * current process is using PMCs.  If so, do exec() time
 	 * processing.  This processing needs to happen AFTER the
 	 * P_INEXEC flag is cleared.
 	 *
 	 * The proc lock needs to be released before taking the PMC
 	 * SX.
 	 */
-	if (PMC_PROC_IS_USING_PMCS(p)) {
+	if (PMC_SYSTEM_SAMPLING_ACTIVE() || PMC_PROC_IS_USING_PMCS(p)) {
 		PROC_UNLOCK(p);
 		PMC_CALL_HOOK_X(td, PMC_FN_PROCESS_EXEC,
 		    (void *) &credential_changing);