From: Andy Shevchenko Date: Fri, 14 Feb 2025 13:43:33 +0000 (+0200) Subject: hrtimers: Replace hrtimer_clock_to_base_table with switch-case X-Git-Tag: v6.15-rc1~204^2~25 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4441b976dfeff0d3579e8da3c0283300c618a553;p=thirdparty%2Flinux.git hrtimers: Replace hrtimer_clock_to_base_table with switch-case 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 Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250214134424.3367619-1-andriy.shevchenko@linux.intel.com --- diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index deb1aa32814e3..453dc76c93484 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -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)