UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

jiffies: Remove HZ > USEC_PER_SEC special case 

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 <riel@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc; John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
This commit is contained in:
Frederic Weisbecker 2014-10-10 02:44:01 +02:00
parent cbfe8fa6cd
commit e075867681
2 changed files with 8 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
include/linux/jiffies.h
View File

@ -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)
{

10
kernel/time/time.c
View File

@ -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;