kern.tty_info_kstacks: add a compact format

Add a more compact display format for kern.tty_info_kstacks inspired by
procstat -kk. Set it as a default one.

# sysctl kern.tty_info_kstacks=1
kern.tty_info_kstacks: 0 -> 1
# sleep 2
^T
load: 0.17  cmd: sleep 623 [nanslp] 0.72r 0.00u 0.00s 0% 2124k
#0 0xffffffff80c4443e at mi_switch+0xbe
#1 0xffffffff80c98044 at sleepq_catch_signals+0x494
#2 0xffffffff80c982c2 at sleepq_timedwait_sig+0x12
#3 0xffffffff80c43af3 at _sleep+0x193
#4 0xffffffff80c50e31 at kern_clock_nanosleep+0x1a1
#5 0xffffffff80c5119b at sys_nanosleep+0x3b
#6 0xffffffff810ffc69 at amd64_syscall+0x119
#7 0xffffffff810d5520 at fast_syscall_common+0x101
sleep: about 1 second(s) left out of the original 2
^C
# sysctl kern.tty_info_kstacks=2
kern.tty_info_kstacks: 1 -> 2
# sleep 2
^T
load: 0.24  cmd: sleep 625 [nanslp] 0.81r 0.00u 0.00s 0% 2124k
mi_switch+0xbe sleepq_catch_signals+0x494 sleepq_timedwait_sig+0x12
sleep+0x193 kern_clock_nanosleep+0x1a1 sys_nanosleep+0x3b
amd64_syscall+0x119 fast_syscall_common+0x101
sleep: about 1 second(s) left out of the original 2
^C

Suggested by:	avg
Reviewed by:	mjg
Relnotes:	yes
Sponsored by:	Mysterious Code Ltd.
Differential Revision:	https://reviews.freebsd.org/D25487
This commit is contained in:
Pawel Biernacki 2020-07-06 16:33:28 +00:00
parent 9eb997cb48
commit cd1c083d80
3 changed files with 60 additions and 13 deletions

View File

@ -170,7 +170,8 @@ stack_print_short_ddb(const struct stack *st)
* flags - M_WAITOK or M_NOWAIT (EWOULDBLOCK).
*/
int
stack_sbuf_print_flags(struct sbuf *sb, const struct stack *st, int flags)
stack_sbuf_print_flags(struct sbuf *sb, const struct stack *st, int flags,
enum stack_sbuf_fmt format)
{
char namebuf[64];
long offset;
@ -182,9 +183,19 @@ stack_sbuf_print_flags(struct sbuf *sb, const struct stack *st, int flags)
&offset, flags);
if (error == EWOULDBLOCK)
return (error);
sbuf_printf(sb, "#%d %p at %s+%#lx\n", i, (void *)st->pcs[i],
namebuf, offset);
switch (format) {
case STACK_SBUF_FMT_LONG:
sbuf_printf(sb, "#%d %p at %s+%#lx\n", i,
(void *)st->pcs[i], namebuf, offset);
break;
case STACK_SBUF_FMT_COMPACT:
sbuf_printf(sb, "%s+%#lx ", namebuf, offset);
break;
default:
__assert_unreachable();
}
}
sbuf_nl_terminate(sb);
return (0);
}
@ -192,7 +203,7 @@ void
stack_sbuf_print(struct sbuf *sb, const struct stack *st)
{
(void)stack_sbuf_print_flags(sb, st, M_WAITOK);
(void)stack_sbuf_print_flags(sb, st, M_WAITOK, STACK_SBUF_FMT_LONG);
}
#if defined(DDB) || defined(WITNESS)

View File

@ -239,10 +239,36 @@ sbuf_tty_drain(void *a, const char *d, int len)
}
#ifdef STACK
static bool tty_info_kstacks = true;
SYSCTL_BOOL(_kern, OID_AUTO, tty_info_kstacks, CTLFLAG_RWTUN,
&tty_info_kstacks, 0,
"Enable printing kernel stack(9) traces on ^T (tty info)");
static int tty_info_kstacks = STACK_SBUF_FMT_LONG;
static int
sysctl_tty_info_kstacks(SYSCTL_HANDLER_ARGS)
{
enum stack_sbuf_fmt val;
int error;
val = tty_info_kstacks;
error = sysctl_handle_int(oidp, &val, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
switch (val) {
case STACK_SBUF_FMT_NONE:
case STACK_SBUF_FMT_LONG:
case STACK_SBUF_FMT_COMPACT:
tty_info_kstacks = val;
break;
default:
error = EINVAL;
}
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, tty_info_kstacks,
CTLFLAG_RWTUN | CTLFLAG_MPSAFE | CTLTYPE_INT, NULL, 0,
sysctl_tty_info_kstacks, "I",
"Adjust format of kernel stack(9) traces on ^T (tty info): "
"0 - disabled; 1 - long; 2 - compact");
#endif
/*
@ -254,7 +280,8 @@ tty_info(struct tty *tp)
struct timeval rtime, utime, stime;
#ifdef STACK
struct stack stack;
int sterr;
int sterr, kstacks_val;
bool print_kstacks;
#endif
struct proc *p, *ppick;
struct thread *td, *tdpick;
@ -337,7 +364,10 @@ tty_info(struct tty *tp)
state = "unknown";
pctcpu = (sched_pctcpu(td) * 10000 + FSCALE / 2) >> FSHIFT;
#ifdef STACK
if (tty_info_kstacks) {
kstacks_val = atomic_load_int(&tty_info_kstacks);
print_kstacks = (kstacks_val != STACK_SBUF_FMT_NONE);
if (print_kstacks) {
if (TD_IS_SWAPPED(td))
sterr = ENOENT;
else
@ -366,8 +396,8 @@ tty_info(struct tty *tp)
pctcpu / 100, rss);
#ifdef STACK
if (tty_info_kstacks && sterr == 0)
stack_sbuf_print_flags(&sb, &stack, M_NOWAIT);
if (print_kstacks && sterr == 0)
stack_sbuf_print_flags(&sb, &stack, M_NOWAIT, kstacks_val);
#endif
out:

View File

@ -39,6 +39,12 @@ MALLOC_DECLARE(M_STACK);
struct sbuf;
enum stack_sbuf_fmt {
STACK_SBUF_FMT_NONE = 0,
STACK_SBUF_FMT_LONG = 1,
STACK_SBUF_FMT_COMPACT = 2,
};
/* MI Routines. */
struct stack *stack_create(int);
void stack_destroy(struct stack *);
@ -52,7 +58,7 @@ void stack_print_short_ddb(const struct stack *);
void stack_sbuf_print(struct sbuf *, const struct stack *);
void stack_sbuf_print_ddb(struct sbuf *, const struct stack *);
int stack_sbuf_print_flags(struct sbuf *, const struct stack *,
int);
int, enum stack_sbuf_fmt);
#ifdef KTR
void stack_ktr(u_int, const char *, int, const struct stack *,
u_int);