[PATCH 3/5] timekeeping/ntp: Constify some function arguments

From: John Stultz
Date: Thu Jul 19 2018 - 20:39:03 EST


From: Ondrej Mosnacek <omosnace@xxxxxxxxxx>

Add 'const' to some function arguments and variables to make it easier
to read the code.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Miroslav Lichvar <mlichvar@xxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx>
[jstultz: Also fixup pre-existing checkpatch warnings for
prototype arguments with no variable name]
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
include/linux/timekeeping.h | 2 +-
kernel/time/ntp.c | 6 +++---
kernel/time/ntp_internal.h | 4 ++--
kernel/time/timekeeping.c | 29 +++++++++++++++--------------
kernel/time/timekeeping_debug.c | 2 +-
kernel/time/timekeeping_internal.h | 2 +-
6 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h
index 86bc202..edace6b 100644
--- a/include/linux/timekeeping.h
+++ b/include/linux/timekeeping.h
@@ -177,7 +177,7 @@ static inline time64_t ktime_get_clocktai_seconds(void)
extern bool timekeeping_rtc_skipsuspend(void);
extern bool timekeeping_rtc_skipresume(void);

-extern void timekeeping_inject_sleeptime64(struct timespec64 *delta);
+extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);

/*
* struct system_time_snapshot - simultaneous raw/real time capture with
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index a627cae..c5e0cba 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -642,7 +642,7 @@ void ntp_notify_cmos_timer(void)
/*
* Propagate a new txc->status value into the NTP state:
*/
-static inline void process_adj_status(struct timex *txc)
+static inline void process_adj_status(const struct timex *txc)
{
if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) {
time_state = TIME_OK;
@@ -665,7 +665,7 @@ static inline void process_adj_status(struct timex *txc)
}


-static inline void process_adjtimex_modes(struct timex *txc, s32 *time_tai)
+static inline void process_adjtimex_modes(const struct timex *txc, s32 *time_tai)
{
if (txc->modes & ADJ_STATUS)
process_adj_status(txc);
@@ -716,7 +716,7 @@ static inline void process_adjtimex_modes(struct timex *txc, s32 *time_tai)
* adjtimex mainly allows reading (and writing, if superuser) of
* kernel time-keeping variables. used by xntpd.
*/
-int __do_adjtimex(struct timex *txc, struct timespec64 *ts, s32 *time_tai)
+int __do_adjtimex(struct timex *txc, const struct timespec64 *ts, s32 *time_tai)
{
int result;

diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h
index 909bd1f..c24b0e1 100644
--- a/kernel/time/ntp_internal.h
+++ b/kernel/time/ntp_internal.h
@@ -8,6 +8,6 @@ extern void ntp_clear(void);
extern u64 ntp_tick_length(void);
extern ktime_t ntp_get_next_leap(void);
extern int second_overflow(time64_t secs);
-extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *);
-extern void __hardpps(const struct timespec64 *, const struct timespec64 *);
+extern int __do_adjtimex(struct timex *txc, const struct timespec64 *ts, s32 *time_tai);
+extern void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts);
#endif /* _LINUX_NTP_INTERNAL_H */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index ad779c2..7033ac1 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -105,7 +105,7 @@ static inline void tk_normalize_xtime(struct timekeeper *tk)
}
}

-static inline struct timespec64 tk_xtime(struct timekeeper *tk)
+static inline struct timespec64 tk_xtime(const struct timekeeper *tk)
{
struct timespec64 ts;

@@ -162,7 +162,7 @@ static inline void tk_update_sleep_time(struct timekeeper *tk, ktime_t delta)
* a read of the fast-timekeeper tkrs (which is protected by its own locking
* and update logic).
*/
-static inline u64 tk_clock_read(struct tk_read_base *tkr)
+static inline u64 tk_clock_read(const struct tk_read_base *tkr)
{
struct clocksource *clock = READ_ONCE(tkr->clock);

@@ -211,7 +211,7 @@ static void timekeeping_check_update(struct timekeeper *tk, u64 offset)
}
}

-static inline u64 timekeeping_get_delta(struct tk_read_base *tkr)
+static inline u64 timekeeping_get_delta(const struct tk_read_base *tkr)
{
struct timekeeper *tk = &tk_core.timekeeper;
u64 now, last, mask, max, delta;
@@ -255,7 +255,7 @@ static inline u64 timekeeping_get_delta(struct tk_read_base *tkr)
static inline void timekeeping_check_update(struct timekeeper *tk, u64 offset)
{
}
-static inline u64 timekeeping_get_delta(struct tk_read_base *tkr)
+static inline u64 timekeeping_get_delta(const struct tk_read_base *tkr)
{
u64 cycle_now, delta;

@@ -352,7 +352,7 @@ u32 (*arch_gettimeoffset)(void) = default_arch_gettimeoffset;
static inline u32 arch_gettimeoffset(void) { return 0; }
#endif

-static inline u64 timekeeping_delta_to_ns(struct tk_read_base *tkr, u64 delta)
+static inline u64 timekeeping_delta_to_ns(const struct tk_read_base *tkr, u64 delta)
{
u64 nsec;

@@ -363,7 +363,7 @@ static inline u64 timekeeping_delta_to_ns(struct tk_read_base *tkr, u64 delta)
return nsec + arch_gettimeoffset();
}

-static inline u64 timekeeping_get_ns(struct tk_read_base *tkr)
+static inline u64 timekeeping_get_ns(const struct tk_read_base *tkr)
{
u64 delta;

@@ -371,7 +371,7 @@ static inline u64 timekeeping_get_ns(struct tk_read_base *tkr)
return timekeeping_delta_to_ns(tkr, delta);
}

-static inline u64 timekeeping_cycles_to_ns(struct tk_read_base *tkr, u64 cycles)
+static inline u64 timekeeping_cycles_to_ns(const struct tk_read_base *tkr, u64 cycles)
{
u64 delta;

@@ -394,7 +394,8 @@ static inline u64 timekeeping_cycles_to_ns(struct tk_read_base *tkr, u64 cycles)
* slightly wrong timestamp (a few nanoseconds). See
* @ktime_get_mono_fast_ns.
*/
-static void update_fast_timekeeper(struct tk_read_base *tkr, struct tk_fast *tkf)
+static void update_fast_timekeeper(const struct tk_read_base *tkr,
+ struct tk_fast *tkf)
{
struct tk_read_base *base = tkf->base;

@@ -549,10 +550,10 @@ EXPORT_SYMBOL_GPL(ktime_get_real_fast_ns);
* number of cycles every time until timekeeping is resumed at which time the
* proper readout base for the fast timekeeper will be restored automatically.
*/
-static void halt_fast_timekeeper(struct timekeeper *tk)
+static void halt_fast_timekeeper(const struct timekeeper *tk)
{
static struct tk_read_base tkr_dummy;
- struct tk_read_base *tkr = &tk->tkr_mono;
+ const struct tk_read_base *tkr = &tk->tkr_mono;

memcpy(&tkr_dummy, tkr, sizeof(tkr_dummy));
cycles_at_suspend = tk_clock_read(tkr);
@@ -1277,7 +1278,7 @@ EXPORT_SYMBOL(do_settimeofday64);
*
* Adds or subtracts an offset value from the current time.
*/
-static int timekeeping_inject_offset(struct timespec64 *ts)
+static int timekeeping_inject_offset(const struct timespec64 *ts)
{
struct timekeeper *tk = &tk_core.timekeeper;
unsigned long flags;
@@ -1585,7 +1586,7 @@ static struct timespec64 timekeeping_suspend_time;
* adds the sleep offset to the timekeeping variables.
*/
static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
- struct timespec64 *delta)
+ const struct timespec64 *delta)
{
if (!timespec64_valid_strict(delta)) {
printk_deferred(KERN_WARNING
@@ -1646,7 +1647,7 @@ bool timekeeping_rtc_skipsuspend(void)
* This function should only be called by rtc_resume(), and allows
* a suspend offset to be injected into the timekeeping values.
*/
-void timekeeping_inject_sleeptime64(struct timespec64 *delta)
+void timekeeping_inject_sleeptime64(const struct timespec64 *delta)
{
struct timekeeper *tk = &tk_core.timekeeper;
unsigned long flags;
@@ -2240,7 +2241,7 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real,
/**
* timekeeping_validate_timex - Ensures the timex is ok for use in do_adjtimex
*/
-static int timekeeping_validate_timex(struct timex *txc)
+static int timekeeping_validate_timex(const struct timex *txc)
{
if (txc->modes & ADJ_ADJTIME) {
/* singleshot must not be used with any other mode bits */
diff --git a/kernel/time/timekeeping_debug.c b/kernel/time/timekeeping_debug.c
index 0754cad..238e4be 100644
--- a/kernel/time/timekeeping_debug.c
+++ b/kernel/time/timekeeping_debug.c
@@ -70,7 +70,7 @@ static int __init tk_debug_sleep_time_init(void)
}
late_initcall(tk_debug_sleep_time_init);

-void tk_debug_account_sleep_time(struct timespec64 *t)
+void tk_debug_account_sleep_time(const struct timespec64 *t)
{
/* Cap bin index so we don't overflow the array */
int bin = min(fls(t->tv_sec), NUM_BINS-1);
diff --git a/kernel/time/timekeeping_internal.h b/kernel/time/timekeeping_internal.h
index cf5c082..bcbb52d 100644
--- a/kernel/time/timekeeping_internal.h
+++ b/kernel/time/timekeeping_internal.h
@@ -8,7 +8,7 @@
#include <linux/time.h>

#ifdef CONFIG_DEBUG_FS
-extern void tk_debug_account_sleep_time(struct timespec64 *t);
+extern void tk_debug_account_sleep_time(const struct timespec64 *t);
#else
#define tk_debug_account_sleep_time(x)
#endif
--
2.7.4