Decode and report native eventfd descriptors from libprocstat and procstat.

Submitted by:   greg@unrelenting.technology
Reviewed by:    markj (previous version)
MFC after:      2 weeks
Differential Revision:  https://reviews.freebsd.org/D26668

lib/libprocstat/libprocstat.c

@@ -628,6 +628,10 @@ procstat_getfiles_kvm(struct procstat *procstat, struct kinfo_proc *kp, int mmap
 			type = PS_FST_TYPE_DEV;
 			data = file.f_data;
 			break;
+		case DTYPE_EVENTFD:
+			type = PS_FST_TYPE_EVENTFD;
+			data = file.f_data;
+			break;
 		default:
 			continue;
 		}
@@ -719,6 +723,7 @@ kinfo_type2fst(int kftype)
 		{ KF_TYPE_SHM, PS_FST_TYPE_SHM },
 		{ KF_TYPE_SOCKET, PS_FST_TYPE_SOCKET },
 		{ KF_TYPE_VNODE, PS_FST_TYPE_VNODE },
+		{ KF_TYPE_EVENTFD, PS_FST_TYPE_EVENTFD },
 		{ KF_TYPE_UNKNOWN, PS_FST_TYPE_UNKNOWN }
 	};
 #define NKFTYPES	(sizeof(kftypes2fst) / sizeof(*kftypes2fst))

lib/libprocstat/libprocstat.h

@@ -72,6 +72,7 @@
 #define	PS_FST_TYPE_NONE	12
 #define	PS_FST_TYPE_PROCDESC	13
 #define	PS_FST_TYPE_DEV		14
+#define	PS_FST_TYPE_EVENTFD	15
 
 /*
  * Special descriptor numbers.

usr.bin/procstat/procstat.1

@@ -313,6 +313,8 @@ The following file descriptor types may be displayed:
 .Bl -tag -width X -compact
 .It e
 POSIX semaphore
+.It E
+eventfd
 .It f
 fifo
 .It h

usr.bin/procstat/procstat_files.c

@@ -414,6 +414,11 @@ procstat_files(struct procstat *procstat, struct kinfo_proc *kipp)
 			xo_emit("{eq:fd_type/dev}");
 			break;
 
+		case PS_FST_TYPE_EVENTFD:
+			str = "E";
+			xo_emit("{eq:fd_type/eventfd}");
+			break;
+
 		case PS_FST_TYPE_NONE:
 			str = "?";
 			xo_emit("{eq:fd_type/none}");