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hrtimers: Replace hrtimer_clock_to_base_table with switch-case

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Clang and GCC complain about overlapped initialisers in the
hrtimer_clock_to_base_table definition. With `make W=1` and CONFIG_WERROR=y
(which is default nowadays) this breaks the build:

  CC      kernel/time/hrtimer.o
kernel/time/hrtimer.c:124:21: error: initializer overrides prior initialization of this subobject [-Werror,-Winitializer-overrides]
  124 |         [CLOCK_REALTIME]        = HRTIMER_BASE_REALTIME,

kernel/time/hrtimer.c:122:27: note: previous initialization is here
  122 |         [0 ... MAX_CLOCKS - 1]  = HRTIMER_MAX_CLOCK_BASES,

(and similar for CLOCK_MONOTONIC, CLOCK_BOOTTIME, and CLOCK_TAI).

hrtimer_clockid_to_base(), which uses the table, is only used in
__hrtimer_init(), which is not a hotpath.

Therefore replace the table lookup with a switch case in
hrtimer_clockid_to_base() to avoid this warning.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250214134424.3367619-1-andriy.shevchenko@linux.intel.com
This commit is contained in:
Andy Shevchenko
2025-02-14 15:43:33 +02:00
committed by Thomas Gleixner
parent 2ea97b76d6
commit 4441b976df
1 changed files with 12 additions and 17 deletions
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29
kernel/time/hrtimer.c
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@@ -117,16 +117,6 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
.csd = CSD_INIT(retrigger_next_event, NULL)
};
static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
/* Make sure we catch unsupported clockids */
[0 ... MAX_CLOCKS - 1] = HRTIMER_MAX_CLOCK_BASES,
[CLOCK_REALTIME] = HRTIMER_BASE_REALTIME,
[CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC,
[CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME,
[CLOCK_TAI] = HRTIMER_BASE_TAI,
};
static inline bool hrtimer_base_is_online(struct hrtimer_cpu_base *base)
{
if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))
@@ -1587,14 +1577,19 @@ u64 hrtimer_next_event_without(const struct hrtimer *exclude)
static inline int hrtimer_clockid_to_base(clockid_t clock_id)
{
if (likely(clock_id < MAX_CLOCKS)) {
int base = hrtimer_clock_to_base_table[clock_id];
if (likely(base != HRTIMER_MAX_CLOCK_BASES))
return base;
switch (clock_id) {
case CLOCK_REALTIME:
return HRTIMER_BASE_REALTIME;
case CLOCK_MONOTONIC:
return HRTIMER_BASE_MONOTONIC;
case CLOCK_BOOTTIME:
return HRTIMER_BASE_BOOTTIME;
case CLOCK_TAI:
return HRTIMER_BASE_TAI;
default:
WARN(1, "Invalid clockid %d. Using MONOTONIC\n", clock_id);
return HRTIMER_BASE_MONOTONIC;
}
WARN(1, "Invalid clockid %d. Using MONOTONIC\n", clock_id);
return HRTIMER_BASE_MONOTONIC;
}
static enum hrtimer_restart hrtimer_dummy_timeout(struct hrtimer *unused)