Re-arrange some variables in kinfo_proc, and add more spare room. This

makes the amount of spare room consistent across architectures, and gets
rid of some cases where space was wasted-and-unusable because types have
different sizes & alignment on different hardware platforms.  This change
causes more variables to move around on i386, and is much less disruptive
on other platforms.  This has been tested on i386, ppc, and sparc, and has
at least been compiled on everything but arm.

Reviewed by:	no objections from freebsd-arch, bde

1 files changed, 51 insertions, 36 deletions

diff --git a/sys/sys/user.h b/sys/sys/user.h
index 6707ade..5c84837 100644
--- a/sys/sys/user.h
+++ b/sys/sys/user.h
@@ -60,48 +60,48 @@
 /*
  * KERN_PROC subtype ops return arrays of selected proc structure entries:
  *
- * When adding new fields to this structure, ALWAYS add them at the end
- * and decrease the size of the spare field by the amount of space that
- * you are adding.  Byte aligned data should be added to the ki_sparestring
- * space; other entries should be added to the ki_spare space. Always
- * verify that sizeof(struct kinfo_proc) == KINFO_PROC_SIZE when you are
- * done. If you change the size of this structure, many programs will stop
- * working! Once you have added the new field, you will need to add code
- * to initialize it in two places: kern/kern_proc.c in the function
- * fill_kinfo_proc and in lib/libkvm/kvm_proc.c in the function kvm_proclist.
+ * This struct includes several arrays of spare space, with different arrays
+ * for different standard C-types.  When adding new variables to this struct,
+ * the space for byte-aligned data should be taken from the ki_sparestring,
+ * pointers from ki_spareptrs, word-aligned data from ki_spareints, and
+ * doubleword-aligned data from ki_sparelongs.  Make sure the space for new
+ * variables come from the array which matches the size and alignment of
+ * those variables on ALL hardware platforms, and then adjust the appropriate
+ * KI_NSPARE_* value(s) to match.
  *
- * KI_NSPARE is the number of spare-longs to define in the array at the
- * end of kinfo_proc.  It may need to be overridden on a platform-specific
- * basis as new fields are added.
+ * Always verify that sizeof(struct kinfo_proc) == KINFO_PROC_SIZE on all
+ * platforms after you have added new variables.  Note that if you change
+ * the value of KINFO_PROC_SIZE, then many userland programs will stop
+ * working until they are recompiled!
+ *
+ * Once you have added the new field, you will need to add code to initialize
+ * it in two places: function fill_kinfo_proc in sys/kern/kern_proc.c and
+ * function kvm_proclist in lib/libkvm/kvm_proc.c .
  */
-#define	KI_NSPARE	15
+#define	KI_NSPARE_INT	10
+#define	KI_NSPARE_LONG	12
+#define	KI_NSPARE_PTR	7
 
 #ifdef __alpha__
-#define	KINFO_PROC_SIZE	912
+#define	KINFO_PROC_SIZE	1088
 #endif
 #ifdef __amd64__
-#define	KINFO_PROC_SIZE	912
+#define	KINFO_PROC_SIZE	1088
 #endif
 #ifdef __arm__
-#undef KI_NSPARE			/* Fewer spare longs on this arch */
-#define	KI_NSPARE	13
-#define	KINFO_PROC_SIZE	648
+#define	KINFO_PROC_SIZE	768		/* value has not been tested... */
 #endif
 #ifdef __ia64__
-#define	KINFO_PROC_SIZE 912
+#define	KINFO_PROC_SIZE 1088
 #endif
 #ifdef __i386__
-#undef KI_NSPARE			/* Fewer spare longs on this arch */
-#define	KI_NSPARE	13
-#define	KINFO_PROC_SIZE	648
+#define	KINFO_PROC_SIZE	768
 #endif
 #ifdef __powerpc__
-#undef KI_NSPARE			/* Fewer spare longs on this arch */
-#define	KI_NSPARE	14
-#define	KINFO_PROC_SIZE	656
+#define	KINFO_PROC_SIZE	768
 #endif
 #ifdef __sparc64__
-#define	KINFO_PROC_SIZE 912
+#define	KINFO_PROC_SIZE 1088
 #endif
 #ifndef KINFO_PROC_SIZE
 #error "Unknown architecture"
@@ -159,6 +159,7 @@ struct kinfo_proc {
 	u_int	ki_estcpu;	 	/* Time averaged value of ki_cpticks */
 	u_int	ki_slptime;	 	/* Time since last blocked */
 	u_int	ki_swtime;	 	/* Time swapped in or out */
+	int	ki_spareint1;	 	/* unused (just here for alignment) */
 	u_int64_t ki_runtime;		/* Real time in microsec */
 	struct	timeval ki_start;	/* starting time */
 	struct	timeval ki_childtime;	/* time used by process children */
@@ -177,23 +178,37 @@ struct kinfo_proc {
 	char	ki_lockname[LOCKNAMELEN+1]; /* lock name */
 	char	ki_comm[COMMLEN+1];	/* command name */
 	char	ki_emul[KI_EMULNAMELEN+1];  /* emulation name */
+	/*
+	 * When adding new variables, take space for char-strings from the
+	 * front of ki_sparestrings, and ints from the end of ki_spareints.
+	 * That way the spare room from both arrays will remain contiguous.
+	 */
 	char	ki_sparestrings[68];	/* spare string space */
-	struct	rusage ki_rusage;	/* process rusage statistics */
-	long	ki_sflag;		/* PS_* flags */
+	int	ki_spareints[KI_NSPARE_INT];	/* spare room for growth */
+	int	ki_jid;			/* Process jail ID */
+	int	ki_numthreads;		/* XXXKSE number of threads in total */
+	lwpid_t	ki_tid;			/* XXXKSE thread id */
 	struct	priority ki_pri;	/* process priority */
-	long	ki_tdflags;		/* XXXKSE kthread flag */
+	struct	rusage ki_rusage;	/* process rusage statistics */
+	/* XXX - most fields in ki_rusage_ch are not (yet) filled in */
+	struct	rusage ki_rusage_ch;	/* rusage of children processes */
 	struct	pcb *ki_pcb;		/* kernel virtual addr of pcb */
 	void	*ki_kstack;		/* kernel virtual addr of stack */
-	struct	timeval ki_childstime;	/* system time used by children */
-	struct	timeval ki_childutime;	/* user time used by children */
-	lwpid_t	ki_tid;			/* XXXKSE thread id */
-	int	ki_numthreads;		/* XXXKSE number of threads in total */
 	void	*ki_udata;		/* User convenience pointer */
-	int	ki_jid;			/* Process jail ID */
-	int	ki_spare_int1;		/* unused (just here for alignment) */
-	long	ki_spare[KI_NSPARE];	/* spare room for later growth */
+	/*
+	 * When adding new variables, take space for pointers from the
+	 * front of ki_spareptrs, and longs from the end of ki_sparelongs.
+	 * That way the spare room from both arrays will remain contiguous.
+	 */
+	void	*ki_spareptrs[KI_NSPARE_PTR];	/* spare room for growth */
+	long	ki_sparelongs[KI_NSPARE_LONG];	/* spare room for growth */
+	long	ki_sflag;		/* PS_* flags */
+	long	ki_tdflags;		/* XXXKSE kthread flag */
 };
 void fill_kinfo_proc(struct proc *, struct kinfo_proc *);
+/* XXX - the following two defines are temporary */
+#define	ki_childstime	ki_rusage_ch.ru_stime
+#define	ki_childutime	ki_rusage_ch.ru_utime
 
 /* ki_sessflag values */
 #define	KI_CTTY		0x00000001	/* controlling tty vnode active */