* [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage
@ 2010-01-27 16:34 Jiri Slaby
2010-01-27 16:34 ` [PATCH 2/2] core: use helpers for rlimits Jiri Slaby
2010-01-28 1:13 ` [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Andrew Morton
0 siblings, 2 replies; 6+ messages in thread
From: Jiri Slaby @ 2010-01-27 16:34 UTC (permalink / raw)
To: mingo; +Cc: akpm, linux-kernel, jirislaby, Peter Zijlstra
Fetch rlimit (both hard and soft) values only once and work on them.
It removes many accesses through sig structure and makes the code
cleaner.
Mostly a preparation for writable resource limits support.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
---
kernel/posix-cpu-timers.c | 32 +++++++++++++++++---------------
1 files changed, 17 insertions(+), 15 deletions(-)
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 9931a64..92c4fa1 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -982,6 +982,7 @@ static void check_thread_timers(struct task_struct *tsk,
int maxfire;
struct list_head *timers = tsk->cpu_timers;
struct signal_struct *const sig = tsk->signal;
+ unsigned long soft;
maxfire = 20;
tsk->cputime_expires.prof_exp = cputime_zero;
@@ -1030,9 +1031,9 @@ static void check_thread_timers(struct task_struct *tsk,
/*
* Check for the special case thread timers.
*/
- if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) {
+ soft = sig->rlim[RLIMIT_RTTIME].rlim_cur;
+ if (soft != RLIM_INFINITY) {
unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max;
- unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur;
if (hard != RLIM_INFINITY &&
tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
@@ -1043,14 +1044,13 @@ static void check_thread_timers(struct task_struct *tsk,
__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
return;
}
- if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) {
+ if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) {
/*
* At the soft limit, send a SIGXCPU every second.
*/
- if (sig->rlim[RLIMIT_RTTIME].rlim_cur
- < sig->rlim[RLIMIT_RTTIME].rlim_max) {
- sig->rlim[RLIMIT_RTTIME].rlim_cur +=
- USEC_PER_SEC;
+ if (soft < hard) {
+ soft += USEC_PER_SEC;
+ sig->rlim[RLIMIT_RTTIME].rlim_cur = soft;
}
printk(KERN_INFO
"RT Watchdog Timeout: %s[%d]\n",
@@ -1125,13 +1125,14 @@ static void check_process_timers(struct task_struct *tsk,
unsigned long long sum_sched_runtime, sched_expires;
struct list_head *timers = sig->cpu_timers;
struct task_cputime cputime;
+ unsigned long cpu_cur_lim = sig->rlim[RLIMIT_CPU].rlim_cur;
/*
* Don't sample the current process CPU clocks if there are no timers.
*/
if (list_empty(&timers[CPUCLOCK_PROF]) &&
cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) &&
- sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY &&
+ cpu_cur_lim == RLIM_INFINITY &&
list_empty(&timers[CPUCLOCK_VIRT]) &&
cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) &&
list_empty(&timers[CPUCLOCK_SCHED])) {
@@ -1198,10 +1199,11 @@ static void check_process_timers(struct task_struct *tsk,
check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime,
SIGVTALRM);
- if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
+ if (cpu_cur_lim != RLIM_INFINITY) {
unsigned long psecs = cputime_to_secs(ptime);
+ unsigned long hard = sig->rlim[RLIMIT_CPU].rlim_max;
cputime_t x;
- if (psecs >= sig->rlim[RLIMIT_CPU].rlim_max) {
+ if (psecs >= hard) {
/*
* At the hard limit, we just die.
* No need to calculate anything else now.
@@ -1209,17 +1211,17 @@ static void check_process_timers(struct task_struct *tsk,
__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
return;
}
- if (psecs >= sig->rlim[RLIMIT_CPU].rlim_cur) {
+ if (psecs >= cpu_cur_lim) {
/*
* At the soft limit, send a SIGXCPU every second.
*/
__group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
- if (sig->rlim[RLIMIT_CPU].rlim_cur
- < sig->rlim[RLIMIT_CPU].rlim_max) {
- sig->rlim[RLIMIT_CPU].rlim_cur++;
+ if (cpu_cur_lim < hard) {
+ cpu_cur_lim++;
+ sig->rlim[RLIMIT_CPU].rlim_cur = cpu_cur_lim;
}
}
- x = secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
+ x = secs_to_cputime(cpu_cur_lim);
if (cputime_eq(prof_expires, cputime_zero) ||
cputime_lt(x, prof_expires)) {
prof_expires = x;
--
1.6.6.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] core: use helpers for rlimits
2010-01-27 16:34 [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Jiri Slaby
@ 2010-01-27 16:34 ` Jiri Slaby
2010-01-28 1:13 ` [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Andrew Morton
1 sibling, 0 replies; 6+ messages in thread
From: Jiri Slaby @ 2010-01-27 16:34 UTC (permalink / raw)
To: mingo; +Cc: akpm, linux-kernel, jirislaby
Make sure compiler won't do weird things with limits. E.g. fetching
them twice may return 2 different values after writable limits are
implemented.
I.e. either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd
or ACCESS_ONCE if not applicable.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
kernel/fork.c | 10 ++++++----
kernel/perf_event.c | 2 +-
kernel/posix-cpu-timers.c | 16 +++++++++-------
kernel/sched.c | 4 ++--
kernel/sched_rt.c | 5 +++--
kernel/signal.c | 2 +-
kernel/sys.c | 3 +--
7 files changed, 23 insertions(+), 19 deletions(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 3d66564..6fca655 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -824,12 +824,14 @@ void __cleanup_sighand(struct sighand_struct *sighand)
*/
static void posix_cpu_timers_init_group(struct signal_struct *sig)
{
+ unsigned long cpu_limit;
+
/* Thread group counters. */
thread_group_cputime_init(sig);
- if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
- sig->cputime_expires.prof_exp =
- secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
+ cpu_limit = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur);
+ if (cpu_limit != RLIM_INFINITY) {
+ sig->cputime_expires.prof_exp = secs_to_cputime(cpu_limit);
sig->cputimer.running = 1;
}
@@ -999,7 +1001,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
#endif
retval = -EAGAIN;
if (atomic_read(&p->real_cred->user->processes) >=
- p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
+ task_rlimit(p, RLIMIT_NPROC)) {
if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
p->real_cred->user != INIT_USER)
goto bad_fork_free;
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index faaa9e6..09e92ba 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2463,7 +2463,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
if (user_locked > user_lock_limit)
extra = user_locked - user_lock_limit;
- lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+ lock_limit = rlimit(RLIMIT_MEMLOCK);
lock_limit >>= PAGE_SHIFT;
locked = vma->vm_mm->locked_vm + extra;
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 92c4fa1..be3fc00 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -639,7 +639,7 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
if (expires_le(sig->it[CPUCLOCK_PROF].expires,
exp->cpu))
break;
- i = sig->rlim[RLIMIT_CPU].rlim_cur;
+ i = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur);
if (i != RLIM_INFINITY &&
i <= cputime_to_secs(exp->cpu))
break;
@@ -1031,9 +1031,10 @@ static void check_thread_timers(struct task_struct *tsk,
/*
* Check for the special case thread timers.
*/
- soft = sig->rlim[RLIMIT_RTTIME].rlim_cur;
+ soft = ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_cur);
if (soft != RLIM_INFINITY) {
- unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max;
+ unsigned long hard = ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].
+ rlim_max);
if (hard != RLIM_INFINITY &&
tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
@@ -1125,7 +1126,7 @@ static void check_process_timers(struct task_struct *tsk,
unsigned long long sum_sched_runtime, sched_expires;
struct list_head *timers = sig->cpu_timers;
struct task_cputime cputime;
- unsigned long cpu_cur_lim = sig->rlim[RLIMIT_CPU].rlim_cur;
+ unsigned long cpu_cur_lim = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur);
/*
* Don't sample the current process CPU clocks if there are no timers.
@@ -1201,7 +1202,8 @@ static void check_process_timers(struct task_struct *tsk,
if (cpu_cur_lim != RLIM_INFINITY) {
unsigned long psecs = cputime_to_secs(ptime);
- unsigned long hard = sig->rlim[RLIMIT_CPU].rlim_max;
+ unsigned long hard =
+ ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_max);
cputime_t x;
if (psecs >= hard) {
/*
@@ -1388,7 +1390,7 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
return 1;
}
- return sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY;
+ return ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur) != RLIM_INFINITY;
}
/*
@@ -1486,7 +1488,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
* If the RLIMIT_CPU timer will expire before the
* ITIMER_PROF timer, we have nothing else to do.
*/
- if (tsk->signal->rlim[RLIMIT_CPU].rlim_cur
+ if (task_rlimit(tsk, RLIMIT_CPU)
< cputime_to_secs(*newval))
return;
}
diff --git a/kernel/sched.c b/kernel/sched.c
index 86b49f9..467fc1a 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6138,7 +6138,7 @@ int can_nice(const struct task_struct *p, const int nice)
/* convert nice value [19,-20] to rlimit style value [1,40] */
int nice_rlim = 20 - nice;
- return (nice_rlim <= p->signal->rlim[RLIMIT_NICE].rlim_cur ||
+ return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
capable(CAP_SYS_NICE));
}
@@ -6315,7 +6315,7 @@ recheck:
if (!lock_task_sighand(p, &flags))
return -ESRCH;
- rlim_rtprio = p->signal->rlim[RLIMIT_RTPRIO].rlim_cur;
+ rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO);
unlock_task_sighand(p, &flags);
/* can't set/change the rt policy */
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index f48328a..552c71e 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1670,8 +1670,9 @@ static void watchdog(struct rq *rq, struct task_struct *p)
if (!p->signal)
return;
- soft = p->signal->rlim[RLIMIT_RTTIME].rlim_cur;
- hard = p->signal->rlim[RLIMIT_RTTIME].rlim_max;
+ /* max may change after cur was read, this will be fixed next tick */
+ soft = task_rlimit(p, RLIMIT_RTTIME);
+ hard = task_rlimit_max(p, RLIMIT_RTTIME);
if (soft != RLIM_INFINITY) {
unsigned long next;
diff --git a/kernel/signal.c b/kernel/signal.c
index 278704b..2213bb4 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -228,7 +228,7 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
if (override_rlimit ||
atomic_read(&user->sigpending) <=
- t->signal->rlim[RLIMIT_SIGPENDING].rlim_cur) {
+ task_rlimit(t, RLIMIT_SIGPENDING)) {
q = kmem_cache_alloc(sigqueue_cachep, flags);
} else {
print_dropped_signal(sig);
diff --git a/kernel/sys.c b/kernel/sys.c
index ef286ab..c9da91a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -574,8 +574,7 @@ static int set_user(struct cred *new)
return -EINVAL;
}
- if (atomic_read(&new_user->processes) >=
- current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
+ if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
new_user != INIT_USER) {
free_uid(new_user);
return -EAGAIN;
--
1.6.6.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage
2010-01-27 16:34 [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Jiri Slaby
2010-01-27 16:34 ` [PATCH 2/2] core: use helpers for rlimits Jiri Slaby
@ 2010-01-28 1:13 ` Andrew Morton
2010-01-28 6:23 ` Jiri Slaby
1 sibling, 1 reply; 6+ messages in thread
From: Andrew Morton @ 2010-01-28 1:13 UTC (permalink / raw)
To: Jiri Slaby; +Cc: mingo, linux-kernel, jirislaby, Peter Zijlstra
On Wed, 27 Jan 2010 17:34:30 +0100
Jiri Slaby <jslaby@suse.cz> wrote:
> Fetch rlimit (both hard and soft) values only once and work on them.
> It removes many accesses through sig structure and makes the code
> cleaner.
The patch doesn't apply for me in semi-serious ways because I applied
rather a lot of timer-related patches:
timer-stats-fix-del_timer_sync-and-try_to_del_timer_sync.patch
posix-cpu-timers-reset-expire-cache-when-no-timer-is-running.patch
hrtimer-correct-a-few-numbers-in-comments.patch
clockevents-ensure-taht-min_delta_ns-is-increased-in-error-path.patch
clocksource-add-argument-to-resume-callback.patch
clocksource-start-cmt-at-clocksource-resume.patch
clocksource-add-suspend-callback.patch
posix-timersc-dont-export-local-functions.patch
timers-introduce-the-concept-of-timer-slack-for-legacy-timers.patch
cpu-timers-simplify-rlimit_cpu-handling.patch
cpu-timers-cleanup-arm_timer.patch
cpu-timers-return-correct-previous-timer-reload-value.patch
cpu-timers-change-sigev_none-timer-implementation.patch
cpu-timers-assure-to-not-iterate-over-all-threads-in-fastpath_timer_check.patch
cpu-timers-optimize-run_posix_cpu_timers.patch
(The above patches are up to six months old. Something isn't working right).
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage
2010-01-28 1:13 ` [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Andrew Morton
@ 2010-01-28 6:23 ` Jiri Slaby
2010-01-28 22:04 ` Jiri Slaby
2010-01-28 22:04 ` [PATCH 2/2] core: use helpers for rlimits Jiri Slaby
0 siblings, 2 replies; 6+ messages in thread
From: Jiri Slaby @ 2010-01-28 6:23 UTC (permalink / raw)
To: Andrew Morton; +Cc: mingo, linux-kernel, Peter Zijlstra
On 01/28/2010 02:13 AM, Andrew Morton wrote:
> posix-timersc-dont-export-local-functions.patch
> cpu-timers-simplify-rlimit_cpu-handling.patch
> cpu-timers-cleanup-arm_timer.patch
> cpu-timers-return-correct-previous-timer-reload-value.patch
> cpu-timers-change-sigev_none-timer-implementation.patch
> cpu-timers-assure-to-not-iterate-over-all-threads-in-fastpath_timer_check.patch
> cpu-timers-optimize-run_posix_cpu_timers.patch
I don't have these in the current mmotm.
> (The above patches are up to six months old. Something isn't working right).
Could you submit a new mmotm, please?
--
js
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage
2010-01-28 6:23 ` Jiri Slaby
@ 2010-01-28 22:04 ` Jiri Slaby
2010-01-28 22:04 ` [PATCH 2/2] core: use helpers for rlimits Jiri Slaby
1 sibling, 0 replies; 6+ messages in thread
From: Jiri Slaby @ 2010-01-28 22:04 UTC (permalink / raw)
To: akpm; +Cc: linux-kernel, jirislaby, Ingo Molnar, Peter Zijlstra
Rebased on the top of mmotm 2010-01-28-01-36. Hopefully this time it will
work out.
--
Fetch rlimit (both hard and soft) values only once and work on them.
It removes many accesses through sig structure and makes the code
cleaner.
Mostly a preparation for writable resource limits support.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
---
kernel/posix-cpu-timers.c | 32 +++++++++++++++++---------------
1 files changed, 17 insertions(+), 15 deletions(-)
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index ffba8f4..417fe38 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -917,6 +917,7 @@ static void check_thread_timers(struct task_struct *tsk,
int maxfire;
struct list_head *timers = tsk->cpu_timers;
struct signal_struct *const sig = tsk->signal;
+ unsigned long soft;
maxfire = 20;
tsk->cputime_expires.prof_exp = cputime_zero;
@@ -965,9 +966,9 @@ static void check_thread_timers(struct task_struct *tsk,
/*
* Check for the special case thread timers.
*/
- if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) {
+ soft = sig->rlim[RLIMIT_RTTIME].rlim_cur;
+ if (soft != RLIM_INFINITY) {
unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max;
- unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur;
if (hard != RLIM_INFINITY &&
tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
@@ -978,14 +979,13 @@ static void check_thread_timers(struct task_struct *tsk,
__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
return;
}
- if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) {
+ if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) {
/*
* At the soft limit, send a SIGXCPU every second.
*/
- if (sig->rlim[RLIMIT_RTTIME].rlim_cur
- < sig->rlim[RLIMIT_RTTIME].rlim_max) {
- sig->rlim[RLIMIT_RTTIME].rlim_cur +=
- USEC_PER_SEC;
+ if (soft < hard) {
+ soft += USEC_PER_SEC;
+ sig->rlim[RLIMIT_RTTIME].rlim_cur = soft;
}
printk(KERN_INFO
"RT Watchdog Timeout: %s[%d]\n",
@@ -1070,6 +1070,7 @@ static void check_process_timers(struct task_struct *tsk,
unsigned long long sum_sched_runtime, sched_expires;
struct list_head *timers = sig->cpu_timers;
struct task_cputime cputime;
+ unsigned long soft;
/*
* Collect the current process totals.
@@ -1129,11 +1130,12 @@ static void check_process_timers(struct task_struct *tsk,
SIGPROF);
check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime,
SIGVTALRM);
-
- if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
+ soft = sig->rlim[RLIMIT_CPU].rlim_cur;
+ if (soft != RLIM_INFINITY) {
unsigned long psecs = cputime_to_secs(ptime);
+ unsigned long hard = sig->rlim[RLIMIT_CPU].rlim_max;
cputime_t x;
- if (psecs >= sig->rlim[RLIMIT_CPU].rlim_max) {
+ if (psecs >= hard) {
/*
* At the hard limit, we just die.
* No need to calculate anything else now.
@@ -1141,17 +1143,17 @@ static void check_process_timers(struct task_struct *tsk,
__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
return;
}
- if (psecs >= sig->rlim[RLIMIT_CPU].rlim_cur) {
+ if (psecs >= soft) {
/*
* At the soft limit, send a SIGXCPU every second.
*/
__group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
- if (sig->rlim[RLIMIT_CPU].rlim_cur
- < sig->rlim[RLIMIT_CPU].rlim_max) {
- sig->rlim[RLIMIT_CPU].rlim_cur++;
+ if (soft < hard) {
+ soft++;
+ sig->rlim[RLIMIT_CPU].rlim_cur = soft;
}
}
- x = secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
+ x = secs_to_cputime(soft);
if (cputime_eq(prof_expires, cputime_zero) ||
cputime_lt(x, prof_expires)) {
prof_expires = x;
--
1.6.6.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] core: use helpers for rlimits
2010-01-28 6:23 ` Jiri Slaby
2010-01-28 22:04 ` Jiri Slaby
@ 2010-01-28 22:04 ` Jiri Slaby
1 sibling, 0 replies; 6+ messages in thread
From: Jiri Slaby @ 2010-01-28 22:04 UTC (permalink / raw)
To: akpm; +Cc: linux-kernel, jirislaby, Ingo Molnar
Make sure compiler won't do weird things with limits. E.g. fetching
them twice may return 2 different values after writable limits are
implemented.
I.e. either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd
or ACCESS_ONCE if not applicable.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
kernel/fork.c | 10 ++++++----
kernel/perf_event.c | 2 +-
kernel/posix-cpu-timers.c | 10 ++++++----
kernel/sched.c | 4 ++--
kernel/sched_rt.c | 5 +++--
kernel/signal.c | 2 +-
kernel/sys.c | 3 +--
7 files changed, 20 insertions(+), 16 deletions(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 3d66564..6fca655 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -824,12 +824,14 @@ void __cleanup_sighand(struct sighand_struct *sighand)
*/
static void posix_cpu_timers_init_group(struct signal_struct *sig)
{
+ unsigned long cpu_limit;
+
/* Thread group counters. */
thread_group_cputime_init(sig);
- if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
- sig->cputime_expires.prof_exp =
- secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
+ cpu_limit = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur);
+ if (cpu_limit != RLIM_INFINITY) {
+ sig->cputime_expires.prof_exp = secs_to_cputime(cpu_limit);
sig->cputimer.running = 1;
}
@@ -999,7 +1001,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
#endif
retval = -EAGAIN;
if (atomic_read(&p->real_cred->user->processes) >=
- p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
+ task_rlimit(p, RLIMIT_NPROC)) {
if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
p->real_cred->user != INIT_USER)
goto bad_fork_free;
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index f1d4b25..0da8415 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2481,7 +2481,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
if (user_locked > user_lock_limit)
extra = user_locked - user_lock_limit;
- lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+ lock_limit = rlimit(RLIMIT_MEMLOCK);
lock_limit >>= PAGE_SHIFT;
locked = vma->vm_mm->locked_vm + extra;
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 417fe38..fd6ea9b 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -966,9 +966,10 @@ static void check_thread_timers(struct task_struct *tsk,
/*
* Check for the special case thread timers.
*/
- soft = sig->rlim[RLIMIT_RTTIME].rlim_cur;
+ soft = ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_cur);
if (soft != RLIM_INFINITY) {
- unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max;
+ unsigned long hard =
+ ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_max);
if (hard != RLIM_INFINITY &&
tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
@@ -1130,10 +1131,11 @@ static void check_process_timers(struct task_struct *tsk,
SIGPROF);
check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime,
SIGVTALRM);
- soft = sig->rlim[RLIMIT_CPU].rlim_cur;
+ soft = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur);
if (soft != RLIM_INFINITY) {
unsigned long psecs = cputime_to_secs(ptime);
- unsigned long hard = sig->rlim[RLIMIT_CPU].rlim_max;
+ unsigned long hard =
+ ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_max);
cputime_t x;
if (psecs >= hard) {
/*
diff --git a/kernel/sched.c b/kernel/sched.c
index 854dd03..c8fd5e1 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6141,7 +6141,7 @@ int can_nice(const struct task_struct *p, const int nice)
/* convert nice value [19,-20] to rlimit style value [1,40] */
int nice_rlim = 20 - nice;
- return (nice_rlim <= p->signal->rlim[RLIMIT_NICE].rlim_cur ||
+ return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
capable(CAP_SYS_NICE));
}
@@ -6318,7 +6318,7 @@ recheck:
if (!lock_task_sighand(p, &flags))
return -ESRCH;
- rlim_rtprio = p->signal->rlim[RLIMIT_RTPRIO].rlim_cur;
+ rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO);
unlock_task_sighand(p, &flags);
/* can't set/change the rt policy */
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 072b3fc..5a86793 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1670,8 +1670,9 @@ static void watchdog(struct rq *rq, struct task_struct *p)
if (!p->signal)
return;
- soft = p->signal->rlim[RLIMIT_RTTIME].rlim_cur;
- hard = p->signal->rlim[RLIMIT_RTTIME].rlim_max;
+ /* max may change after cur was read, this will be fixed next tick */
+ soft = task_rlimit(p, RLIMIT_RTTIME);
+ hard = task_rlimit_max(p, RLIMIT_RTTIME);
if (soft != RLIM_INFINITY) {
unsigned long next;
diff --git a/kernel/signal.c b/kernel/signal.c
index 278704b..2213bb4 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -228,7 +228,7 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
if (override_rlimit ||
atomic_read(&user->sigpending) <=
- t->signal->rlim[RLIMIT_SIGPENDING].rlim_cur) {
+ task_rlimit(t, RLIMIT_SIGPENDING)) {
q = kmem_cache_alloc(sigqueue_cachep, flags);
} else {
print_dropped_signal(sig);
diff --git a/kernel/sys.c b/kernel/sys.c
index ef286ab..c9da91a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -574,8 +574,7 @@ static int set_user(struct cred *new)
return -EINVAL;
}
- if (atomic_read(&new_user->processes) >=
- current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
+ if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
new_user != INIT_USER) {
free_uid(new_user);
return -EAGAIN;
--
1.6.6.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-01-28 22:04 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-01-27 16:34 [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Jiri Slaby
2010-01-27 16:34 ` [PATCH 2/2] core: use helpers for rlimits Jiri Slaby
2010-01-28 1:13 ` [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Andrew Morton
2010-01-28 6:23 ` Jiri Slaby
2010-01-28 22:04 ` Jiri Slaby
2010-01-28 22:04 ` [PATCH 2/2] core: use helpers for rlimits Jiri Slaby
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).