linux-kernel - [tip: timers/core] timekeeping: Refactor timekeeping helpers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Mon, 08 Apr 2024 13:10:35 -0000
From: "tip-bot2 for Adrian Hunter" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: Thomas Gleixner <tglx@...utronix.de>,
 Adrian Hunter <adrian.hunter@...el.com>, x86@...nel.org,
 linux-kernel@...r.kernel.org
Subject: [tip: timers/core] timekeeping: Refactor timekeeping helpers

The following commit has been merged into the timers/core branch of tip:

Commit-ID:     e8e9d21a5df655a62ab4611fd437fb7510d2f85c
Gitweb:        https://git.kernel.org/tip/e8e9d21a5df655a62ab4611fd437fb7510d2f85c
Author:        Adrian Hunter <adrian.hunter@...el.com>
AuthorDate:    Mon, 25 Mar 2024 08:40:17 +02:00
Committer:     Thomas Gleixner <tglx@...utronix.de>
CommitterDate: Mon, 08 Apr 2024 15:03:08 +02:00

timekeeping: Refactor timekeeping helpers

Simplify the usage of timekeeping sanity checking, in preparation for
consolidating timekeeping helpers. This works towards eliminating
timekeeping_delta_to_ns() in favour of timekeeping_cycles_to_ns().

No functional change.

Suggested-by: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Link: https://lore.kernel.org/r/20240325064023.2997-14-adrian.hunter@intel.com

---
 kernel/time/timekeeping.c | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index f81d675..618328c 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -237,7 +237,7 @@ static void timekeeping_check_update(struct timekeeper *tk, u64 offset)
 	}
 }
 
-static inline u64 timekeeping_get_delta(const struct tk_read_base *tkr)
+static inline u64 timekeeping_debug_get_delta(const struct tk_read_base *tkr)
 {
 	struct timekeeper *tk = &tk_core.timekeeper;
 	u64 now, last, mask, max, delta;
@@ -281,17 +281,9 @@ static inline u64 timekeeping_get_delta(const struct tk_read_base *tkr)
 static inline void timekeeping_check_update(struct timekeeper *tk, u64 offset)
 {
 }
-static inline u64 timekeeping_get_delta(const struct tk_read_base *tkr)
+static inline u64 timekeeping_debug_get_delta(const struct tk_read_base *tkr)
 {
-	u64 cycle_now, delta;
-
-	/* read clocksource */
-	cycle_now = tk_clock_read(tkr);
-
-	/* calculate the delta since the last update_wall_time */
-	delta = clocksource_delta(cycle_now, tkr->cycle_last, tkr->mask);
-
-	return delta;
+	BUG();
 }
 #endif
 
@@ -396,10 +388,10 @@ static __always_inline u64 __timekeeping_get_ns(const struct tk_read_base *tkr)
 
 static inline u64 timekeeping_get_ns(const struct tk_read_base *tkr)
 {
-	u64 delta;
+	if (IS_ENABLED(CONFIG_DEBUG_TIMEKEEPING))
+		return timekeeping_delta_to_ns(tkr, timekeeping_debug_get_delta(tkr));
 
-	delta = timekeeping_get_delta(tkr);
-	return timekeeping_delta_to_ns(tkr, delta);
+	return __timekeeping_get_ns(tkr);
 }
 
 /**