That set has jiffies/cputime cleanups and fixes that were previously
posted and a change on tilegx driver to be isolation-friendly.
If nobody opposes, I'll make a pull request to Ingo in a few days.
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
timers/core-v3
HEAD: 572536be5b8e84c507d66203f53faa0ae2c8c244
Thanks,
Frederic
---
Frederic Weisbecker (3):
jiffies: Remove HZ > USEC_PER_SEC special case
apm32: Fix cputime == jiffies assumption
alpha: Fix jiffies based cputime assumption
Chris Metcalf (1):
nohz: Prevent tilegx network driver interrupts
arch/alpha/kernel/osf_sys.c | 13 +++++++++----
arch/x86/kernel/apm_32.c | 2 +-
drivers/net/ethernet/tile/tilegx.c | 4 +++-
include/linux/jiffies.h | 9 +--------
include/linux/tick.h | 9 +++++++++
kernel/time/time.c | 10 +++++++---
6 files changed, 30 insertions(+), 17 deletions(-)
HZ never goes much further 1000 and a bit. And if we ever reach one tick
per microsecond, we might be having a problem.
Lets stop maintaining this special case, just leave a paranoid check.
Reviewed-by: Rik van Riel <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc; John Stultz <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Viresh Kumar <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
---
include/linux/jiffies.h | 9 +--------
kernel/time/time.c | 10 +++++++---
2 files changed, 8 insertions(+), 11 deletions(-)
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h
index 535fd3b..7c6febe 100644
--- a/include/linux/jiffies.h
+++ b/include/linux/jiffies.h
@@ -363,18 +363,11 @@ static inline unsigned long msecs_to_jiffies(const unsigned int m)
}
extern unsigned long __usecs_to_jiffies(const unsigned int u);
-#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ)
+#if !(USEC_PER_SEC % HZ)
static inline unsigned long _usecs_to_jiffies(const unsigned int u)
{
return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ);
}
-#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
-static inline unsigned long _usecs_to_jiffies(const unsigned int u)
-{
- return u * (HZ / USEC_PER_SEC);
-}
-static inline unsigned long _usecs_to_jiffies(const unsigned int u)
-{
#else
static inline unsigned long _usecs_to_jiffies(const unsigned int u)
{
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 85d5bb1..ad1bf23 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -268,10 +268,14 @@ EXPORT_SYMBOL(jiffies_to_msecs);
unsigned int jiffies_to_usecs(const unsigned long j)
{
-#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ)
+ /*
+ * Hz usually doesn't go much further MSEC_PER_SEC.
+ * jiffies_to_usecs() and usecs_to_jiffies() depend on that.
+ */
+ BUILD_BUG_ON(HZ > USEC_PER_SEC);
+
+#if !(USEC_PER_SEC % HZ)
return (USEC_PER_SEC / HZ) * j;
-#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
- return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC);
#else
# if BITS_PER_LONG == 32
return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
--
2.1.4
That code wrongly assumes that cputime_t wraps jiffies_t. Lets use
the correct accessors/mutators.
No real harm now as that code can't be used with full dynticks.
Reviewed-by: Rik van Riel <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc; John Stultz <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Viresh Kumar <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
---
arch/x86/kernel/apm_32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index 927ec92..052c9c3 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -919,7 +919,7 @@ recalc:
} else if (jiffies_since_last_check > idle_period) {
unsigned int idle_percentage;
- idle_percentage = stime - last_stime;
+ idle_percentage = cputime_to_jiffies(stime - last_stime);
idle_percentage *= 100;
idle_percentage /= jiffies_since_last_check;
use_apm_idle = (idle_percentage > idle_threshold);
--
2.1.4
That code wrongly assumes that cputime_t wraps jiffies_t. Lets use
the correct accessors/mutators.
In practice there should be no harm yet because alpha currently
only support tick based cputime accounting which is always jiffies
based.
Reviewed-by: Rik van Riel <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc; John Stultz <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Viresh Kumar <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
---
arch/alpha/kernel/osf_sys.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 36dc91a..6cc0816 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -1138,6 +1138,7 @@ SYSCALL_DEFINE2(osf_getrusage, int, who, struct rusage32 __user *, ru)
{
struct rusage32 r;
cputime_t utime, stime;
+ unsigned long utime_jiffies, stime_jiffies;
if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
return -EINVAL;
@@ -1146,14 +1147,18 @@ SYSCALL_DEFINE2(osf_getrusage, int, who, struct rusage32 __user *, ru)
switch (who) {
case RUSAGE_SELF:
task_cputime(current, &utime, &stime);
- jiffies_to_timeval32(utime, &r.ru_utime);
- jiffies_to_timeval32(stime, &r.ru_stime);
+ utime_jiffies = cputime_to_jiffies(utime);
+ stime_jiffies = cputime_to_jiffies(stime);
+ jiffies_to_timeval32(utime_jiffies, &r.ru_utime);
+ jiffies_to_timeval32(stime_jiffies, &r.ru_stime);
r.ru_minflt = current->min_flt;
r.ru_majflt = current->maj_flt;
break;
case RUSAGE_CHILDREN:
- jiffies_to_timeval32(current->signal->cutime, &r.ru_utime);
- jiffies_to_timeval32(current->signal->cstime, &r.ru_stime);
+ utime_jiffies = cputime_to_jiffies(current->signal->cutime);
+ stime_jiffies = cputime_to_jiffies(current->signal->cstime);
+ jiffies_to_timeval32(utime_jiffies, &r.ru_utime);
+ jiffies_to_timeval32(stime_jiffies, &r.ru_stime);
r.ru_minflt = current->signal->cmin_flt;
r.ru_majflt = current->signal->cmaj_flt;
break;
--
2.1.4
From: Chris Metcalf <[email protected]>
Normally the tilegx networking shim sends irqs to all the cores
to distribute the load of processing incoming-packet interrupts,
so that you can get to multiple Gb's of traffic inbound.
However, in nohz_full mode we don't want to interrupt the
nohz_full cores by default, so we limit the set of cores we use
to only the online housekeeping cores.
To make client code easier to read, we introduce a new nohz_full
accessor, housekeeping_cpumask(), which returns a pointer to the
housekeeping_mask if nohz_full is enabled, and otherwise returns
the cpu_possible_mask.
Signed-off-by: Chris Metcalf <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Viresh Kumar <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
---
drivers/net/ethernet/tile/tilegx.c | 4 +++-
include/linux/tick.h | 9 +++++++++
2 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c
index a3f7610..0a15acc 100644
--- a/drivers/net/ethernet/tile/tilegx.c
+++ b/drivers/net/ethernet/tile/tilegx.c
@@ -40,6 +40,7 @@
#include <linux/tcp.h>
#include <linux/net_tstamp.h>
#include <linux/ptp_clock_kernel.h>
+#include <linux/tick.h>
#include <asm/checksum.h>
#include <asm/homecache.h>
@@ -2273,7 +2274,8 @@ static int __init tile_net_init_module(void)
tile_net_dev_init(name, mac);
if (!network_cpus_init())
- network_cpus_map = *cpu_online_mask;
+ cpumask_and(&network_cpus_map, housekeeping_cpumask(),
+ cpu_online_mask);
return 0;
}
diff --git a/include/linux/tick.h b/include/linux/tick.h
index edbfc9a..1ca93f2 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -163,6 +163,15 @@ static inline void tick_nohz_full_kick_all(void) { }
static inline void __tick_nohz_task_switch(struct task_struct *tsk) { }
#endif
+static inline const struct cpumask *housekeeping_cpumask(void)
+{
+#ifdef CONFIG_NO_HZ_FULL
+ if (tick_nohz_full_enabled())
+ return housekeeping_mask;
+#endif
+ return cpu_possible_mask;
+}
+
static inline bool is_housekeeping_cpu(int cpu)
{
#ifdef CONFIG_NO_HZ_FULL
--
2.1.4