Use boot based time for process start time and boot time in /proc

Commit 411187fb05cd11676b0979d9fbf3291db69dbce2 caused boot time to move and
process start times to become invalid after suspend.  Using boot based time
for those restores the old behaviour and fixes the issue.

[akpm@linux-foundation.org: little cleanup]
Signed-off-by: Tomas Janousek <tjanouse@redhat.com>
Cc: Tomas Smetana <tsmetana@redhat.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 98e78e2f18d66cb4331d394c8543c3e8db4445a4..680c913575f0bd41ea7374929258d21cecb5f75d 100644 (file)
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -440,8 +440,9 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole)
 
        /* Temporary variable needed for gcc-2.96 */
        /* convert timespec -> nsec*/
-       start_time = (unsigned long long)task->start_time.tv_sec * NSEC_PER_SEC
-                               + task->start_time.tv_nsec;
+       start_time =
+               (unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
+                               + task->real_start_time.tv_nsec;
        /* convert nsec -> ticks */
        start_time = nsec_to_clock_t(start_time);
 

diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 5fd49e47f83a7c8a1d20ee07d6d6e13d0df9d6ab..19c9cbf1c320e24f1f05d5730d6c93651ae91af7 100644 (file)
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -443,12 +443,12 @@ static int show_stat(struct seq_file *p, void *v)
        unsigned long jif;
        cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
        u64 sum = 0;
+       struct timespec boottime;
 
        user = nice = system = idle = iowait =
                irq = softirq = steal = cputime64_zero;
-       jif = - wall_to_monotonic.tv_sec;
-       if (wall_to_monotonic.tv_nsec)
-               --jif;
+       getboottime(&boottime);
+       jif = boottime.tv_sec;
 
        for_each_possible_cpu(i) {
                int j;

diff --git a/include/linux/sched.h b/include/linux/sched.h
index cfb680585ab8bd87762fe3e9b2bedfb404882760..3cffc120466394926fe1eedbcfdf5e9b5b0ced4c 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -972,7 +972,8 @@ struct task_struct {
        unsigned int rt_priority;
        cputime_t utime, stime;
        unsigned long nvcsw, nivcsw; /* context switch counts */
-       struct timespec start_time;
+       struct timespec start_time;             /* monotonic time */
+       struct timespec real_start_time;        /* boot based time */
 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
        unsigned long min_flt, maj_flt;
 

diff --git a/kernel/fork.c b/kernel/fork.c
index da3a155bba0ddc5c50a8082833a90be6fe60e8ce..344d693fdc787c153ca702a3d3481031164a964a 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1059,6 +1059,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
        p->lock_depth = -1;             /* -1 = no lock */
        do_posix_clock_monotonic_gettime(&p->start_time);
+       p->real_start_time = p->start_time;
+       monotonic_to_bootbased(&p->real_start_time);
        p->security = NULL;
        p->io_context = NULL;
        p->io_wait = NULL;