From: Peter Zijlstra <peterz@infradead.org>
To: x86@kernel.org, mathias.nyman@linux.intel.com,
gregkh@linuxfoundation.org
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org,
rdunlap@infradead.org, linux-usb@vger.kernel.org
Subject: [PATCH 1/3] x86/tsc: Be consistent about use_tsc_delay()
Date: Fri, 04 Mar 2022 16:19:54 +0100 [thread overview]
Message-ID: <20220304152135.914397165@infradead.org> (raw)
In-Reply-To: 20220304151953.830111479@infradead.org
Currently loops_per_jiffy is set in tsc_early_init(), but then don't
switch to delay_tsc, with the result that delay_loop is used with
loops_per_jiffy set for delay_tsc.
Then in (late) tsc_init() lpj_fine is set (which is mostly unused) and
after which use_tsc_delay() is finally called.
Move both loops_per_jiffy and use_tsc_delay() into
tsc_enable_sched_clock() which is called the moment tsc_khz is
determined, be it early or late. Keeping the lot consistent.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/kernel/tsc.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1487,6 +1487,9 @@ static unsigned long __init get_loops_pe
static void __init tsc_enable_sched_clock(void)
{
+ loops_per_jiffy = get_loops_per_jiffy();
+ use_tsc_delay();
+
/* Sanitize TSC ADJUST before cyc2ns gets initialized */
tsc_store_and_check_tsc_adjust(true);
cyc2ns_init_boot_cpu();
@@ -1502,8 +1505,6 @@ void __init tsc_early_init(void)
return;
if (!determine_cpu_tsc_frequencies(true))
return;
- loops_per_jiffy = get_loops_per_jiffy();
-
tsc_enable_sched_clock();
}
@@ -1537,7 +1538,6 @@ void __init tsc_init(void)
enable_sched_clock_irqtime();
lpj_fine = get_loops_per_jiffy();
- use_tsc_delay();
check_system_tsc_reliable();
next prev parent reply other threads:[~2022-03-04 15:22 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-04 15:19 [PATCH 0/3] x86: Make XDBC work Peter Zijlstra
2022-03-04 15:19 ` Peter Zijlstra [this message]
2022-03-04 15:19 ` [PATCH 2/3] usb: early: xhci-dbc: Remove duplicate keep parsing Peter Zijlstra
2022-03-04 15:19 ` [PATCH 3/3] usb: early: xhci-dbc: Fix xdbc number parsing Peter Zijlstra
2022-03-08 10:01 ` Mathias Nyman
2022-04-20 3:14 ` [PATCH 0/3] x86: Make XDBC work Randy Dunlap
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220304152135.914397165@infradead.org \
--to=peterz@infradead.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=mathias.nyman@linux.intel.com \
--cc=rdunlap@infradead.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox