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-rw-r--r--kernel/futex.c53
-rw-r--r--kernel/posix-cpu-timers.c60
-rw-r--r--kernel/trace/Kconfig23
-rw-r--r--kernel/trace/trace_mmiotrace.c14
-rw-r--r--kernel/user.c3
5 files changed, 92 insertions, 61 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index f89d373a9c6..438701adce2 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1165,6 +1165,7 @@ static int futex_wait(u32 __user *uaddr, int fshared,
u32 val, ktime_t *abs_time, u32 bitset, int clockrt)
{
struct task_struct *curr = current;
+ struct restart_block *restart;
DECLARE_WAITQUEUE(wait, curr);
struct futex_hash_bucket *hb;
struct futex_q q;
@@ -1216,11 +1217,13 @@ retry:
if (!ret)
goto retry;
- return ret;
+ goto out;
}
ret = -EWOULDBLOCK;
- if (uval != val)
- goto out_unlock_put_key;
+ if (unlikely(uval != val)) {
+ queue_unlock(&q, hb);
+ goto out_put_key;
+ }
/* Only actually queue if *uaddr contained val. */
queue_me(&q, hb);
@@ -1284,38 +1287,38 @@ retry:
*/
/* If we were woken (and unqueued), we succeeded, whatever. */
+ ret = 0;
if (!unqueue_me(&q))
- return 0;
+ goto out_put_key;
+ ret = -ETIMEDOUT;
if (rem)
- return -ETIMEDOUT;
+ goto out_put_key;
/*
* We expect signal_pending(current), but another thread may
* have handled it for us already.
*/
+ ret = -ERESTARTSYS;
if (!abs_time)
- return -ERESTARTSYS;
- else {
- struct restart_block *restart;
- restart = &current_thread_info()->restart_block;
- restart->fn = futex_wait_restart;
- restart->futex.uaddr = (u32 *)uaddr;
- restart->futex.val = val;
- restart->futex.time = abs_time->tv64;
- restart->futex.bitset = bitset;
- restart->futex.flags = 0;
-
- if (fshared)
- restart->futex.flags |= FLAGS_SHARED;
- if (clockrt)
- restart->futex.flags |= FLAGS_CLOCKRT;
- return -ERESTART_RESTARTBLOCK;
- }
+ goto out_put_key;
-out_unlock_put_key:
- queue_unlock(&q, hb);
- put_futex_key(fshared, &q.key);
+ restart = &current_thread_info()->restart_block;
+ restart->fn = futex_wait_restart;
+ restart->futex.uaddr = (u32 *)uaddr;
+ restart->futex.val = val;
+ restart->futex.time = abs_time->tv64;
+ restart->futex.bitset = bitset;
+ restart->futex.flags = 0;
+
+ if (fshared)
+ restart->futex.flags |= FLAGS_SHARED;
+ if (clockrt)
+ restart->futex.flags |= FLAGS_CLOCKRT;
+ ret = -ERESTART_RESTARTBLOCK;
+
+out_put_key:
+ put_futex_key(fshared, &q.key);
out:
return ret;
}
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 2313a4cc14e..e976e505648 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -681,6 +681,33 @@ static void cpu_timer_fire(struct k_itimer *timer)
}
/*
+ * Sample a process (thread group) timer for the given group_leader task.
+ * Must be called with tasklist_lock held for reading.
+ */
+static int cpu_timer_sample_group(const clockid_t which_clock,
+ struct task_struct *p,
+ union cpu_time_count *cpu)
+{
+ struct task_cputime cputime;
+
+ thread_group_cputimer(p, &cputime);
+ switch (CPUCLOCK_WHICH(which_clock)) {
+ default:
+ return -EINVAL;
+ case CPUCLOCK_PROF:
+ cpu->cpu = cputime_add(cputime.utime, cputime.stime);
+ break;
+ case CPUCLOCK_VIRT:
+ cpu->cpu = cputime.utime;
+ break;
+ case CPUCLOCK_SCHED:
+ cpu->sched = cputime.sum_exec_runtime + task_delta_exec(p);
+ break;
+ }
+ return 0;
+}
+
+/*
* Guts of sys_timer_settime for CPU timers.
* This is called with the timer locked and interrupts disabled.
* If we return TIMER_RETRY, it's necessary to release the timer's lock
@@ -741,7 +768,7 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
cpu_clock_sample(timer->it_clock, p, &val);
} else {
- cpu_clock_sample_group(timer->it_clock, p, &val);
+ cpu_timer_sample_group(timer->it_clock, p, &val);
}
if (old) {
@@ -889,7 +916,7 @@ void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp)
read_unlock(&tasklist_lock);
goto dead;
} else {
- cpu_clock_sample_group(timer->it_clock, p, &now);
+ cpu_timer_sample_group(timer->it_clock, p, &now);
clear_dead = (unlikely(p->exit_state) &&
thread_group_empty(p));
}
@@ -1244,7 +1271,7 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
clear_dead_task(timer, now);
goto out_unlock;
}
- cpu_clock_sample_group(timer->it_clock, p, &now);
+ cpu_timer_sample_group(timer->it_clock, p, &now);
bump_cpu_timer(timer, now);
/* Leave the tasklist_lock locked for the call below. */
}
@@ -1409,33 +1436,6 @@ void run_posix_cpu_timers(struct task_struct *tsk)
}
/*
- * Sample a process (thread group) timer for the given group_leader task.
- * Must be called with tasklist_lock held for reading.
- */
-static int cpu_timer_sample_group(const clockid_t which_clock,
- struct task_struct *p,
- union cpu_time_count *cpu)
-{
- struct task_cputime cputime;
-
- thread_group_cputimer(p, &cputime);
- switch (CPUCLOCK_WHICH(which_clock)) {
- default:
- return -EINVAL;
- case CPUCLOCK_PROF:
- cpu->cpu = cputime_add(cputime.utime, cputime.stime);
- break;
- case CPUCLOCK_VIRT:
- cpu->cpu = cputime.utime;
- break;
- case CPUCLOCK_SCHED:
- cpu->sched = cputime.sum_exec_runtime + task_delta_exec(p);
- break;
- }
- return 0;
-}
-
-/*
* Set one of the process-wide special case CPU timers.
* The tsk->sighand->siglock must be held by the caller.
* The *newval argument is relative and we update it to be absolute, *oldval
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index e2a4ff6fc3a..58a93fbd68a 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -302,4 +302,27 @@ config FTRACE_STARTUP_TEST
functioning properly. It will do tests on all the configured
tracers of ftrace.
+config MMIOTRACE
+ bool "Memory mapped IO tracing"
+ depends on HAVE_MMIOTRACE_SUPPORT && DEBUG_KERNEL && PCI
+ select TRACING
+ help
+ Mmiotrace traces Memory Mapped I/O access and is meant for
+ debugging and reverse engineering. It is called from the ioremap
+ implementation and works via page faults. Tracing is disabled by
+ default and can be enabled at run-time.
+
+ See Documentation/tracers/mmiotrace.txt.
+ If you are not helping to develop drivers, say N.
+
+config MMIOTRACE_TEST
+ tristate "Test module for mmiotrace"
+ depends on MMIOTRACE && m
+ help
+ This is a dumb module for testing mmiotrace. It is very dangerous
+ as it will write garbage to IO memory starting at a given address.
+ However, it should be safe to use on e.g. unused portion of VRAM.
+
+ Say N, unless you absolutely know what you are doing.
+
endmenu
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index fffcb069f1d..80e503ef613 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -9,6 +9,7 @@
#include <linux/kernel.h>
#include <linux/mmiotrace.h>
#include <linux/pci.h>
+#include <asm/atomic.h>
#include "trace.h"
@@ -19,6 +20,7 @@ struct header_iter {
static struct trace_array *mmio_trace_array;
static bool overrun_detected;
static unsigned long prev_overruns;
+static atomic_t dropped_count;
static void mmio_reset_data(struct trace_array *tr)
{
@@ -121,11 +123,11 @@ static void mmio_close(struct trace_iterator *iter)
static unsigned long count_overruns(struct trace_iterator *iter)
{
- unsigned long cnt = 0;
+ unsigned long cnt = atomic_xchg(&dropped_count, 0);
unsigned long over = ring_buffer_overruns(iter->tr->buffer);
if (over > prev_overruns)
- cnt = over - prev_overruns;
+ cnt += over - prev_overruns;
prev_overruns = over;
return cnt;
}
@@ -310,8 +312,10 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
&irq_flags);
- if (!event)
+ if (!event) {
+ atomic_inc(&dropped_count);
return;
+ }
entry = ring_buffer_event_data(event);
tracing_generic_entry_update(&entry->ent, 0, preempt_count());
entry->ent.type = TRACE_MMIO_RW;
@@ -338,8 +342,10 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
&irq_flags);
- if (!event)
+ if (!event) {
+ atomic_inc(&dropped_count);
return;
+ }
entry = ring_buffer_event_data(event);
tracing_generic_entry_update(&entry->ent, 0, preempt_count());
entry->ent.type = TRACE_MMIO_MAP;
diff --git a/kernel/user.c b/kernel/user.c
index 477b6660f44..3551ac74239 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -72,6 +72,7 @@ static void uid_hash_insert(struct user_struct *up, struct hlist_head *hashent)
static void uid_hash_remove(struct user_struct *up)
{
hlist_del_init(&up->uidhash_node);
+ put_user_ns(up->user_ns);
}
static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent)
@@ -334,7 +335,6 @@ static void free_user(struct user_struct *up, unsigned long flags)
atomic_inc(&up->__count);
spin_unlock_irqrestore(&uidhash_lock, flags);
- put_user_ns(up->user_ns);
INIT_WORK(&up->work, remove_user_sysfs_dir);
schedule_work(&up->work);
}
@@ -357,7 +357,6 @@ static void free_user(struct user_struct *up, unsigned long flags)
sched_destroy_user(up);
key_put(up->uid_keyring);
key_put(up->session_keyring);
- put_user_ns(up->user_ns);
kmem_cache_free(uid_cachep, up);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-22 11:21:40 +0000