From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Linux PM <linux-pm@vger.kernel.org>,
Viresh Kumar <viresh.kumar@linaro.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH v2] cpufreq: Make cpufreq_online() call driver->offline() on errors
Date: Tue, 22 Jun 2021 21:11:39 +0200 [thread overview]
Message-ID: <5490292.DvuYhMxLoT@kreacher> (raw)
In-Reply-To: <11788436.O9o76ZdvQC@kreacher>
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subject: [PATCH] cpufreq: Make cpufreq_online() call driver->offline() on errors
In the CPU removal path the ->offline() callback provided by the
driver is always invoked before ->exit(), but in the cpufreq_online()
error path it is not, so ->exit() is expected to somehow know the
context in which it has been called and act accordingly.
That is less than straightforward, so make cpufreq_online() invoke
the driver's ->offline() callback, if present, on errors before
->exit() too.
This only potentially affects intel_pstate.
Fixes: 91a12e91dc39 ("cpufreq: Allow light-weight tear down and bring up of CPUs")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
-> v2:
* Avoid calling ->offline() after a failing ->online().
* Add a comment regarding the expected state after calling ->init().
* Edit the changelog a bit.
---
drivers/cpufreq/cpufreq.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
Index: linux-pm/drivers/cpufreq/cpufreq.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq.c
+++ linux-pm/drivers/cpufreq/cpufreq.c
@@ -1367,9 +1367,14 @@ static int cpufreq_online(unsigned int c
goto out_free_policy;
}
+ /*
+ * The initialization has succeeded and the policy is online.
+ * If there is a problem with its frequency table, take it
+ * offline and drop it.
+ */
ret = cpufreq_table_validate_and_sort(policy);
if (ret)
- goto out_exit_policy;
+ goto out_offline_policy;
/* related_cpus should at least include policy->cpus. */
cpumask_copy(policy->related_cpus, policy->cpus);
@@ -1515,6 +1520,10 @@ out_destroy_policy:
up_write(&policy->rwsem);
+out_offline_policy:
+ if (cpufreq_driver->offline)
+ cpufreq_driver->offline(policy);
+
out_exit_policy:
if (cpufreq_driver->exit)
cpufreq_driver->exit(policy);
next prev parent reply other threads:[~2021-06-22 19:11 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-21 17:26 [PATCH] cpufreq: Make cpufreq_online() call driver->offline() on errors Rafael J. Wysocki
2021-06-22 6:20 ` Viresh Kumar
2021-06-22 12:18 ` Rafael J. Wysocki
2021-06-22 19:11 ` Rafael J. Wysocki [this message]
2021-06-23 3:10 ` [PATCH v2] " Viresh Kumar
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=5490292.DvuYhMxLoT@kreacher \
--to=rjw@rjwysocki.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=viresh.kumar@linaro.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;
as well as URLs for NNTP newsgroup(s).