| 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
| ||
|
Message-Id: <20180803200511.189664-3-mka@chromium.org>
Date: Fri, 3 Aug 2018 13:05:10 -0700
From: Matthias Kaehlcke <mka@...omium.org>
To: MyungJoo Ham <myungjoo.ham@...sung.com>,
Kyungmin Park <kyungmin.park@...sung.com>,
Chanwoo Choi <cw00.choi@...sung.com>
Cc: linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
Brian Norris <briannorris@...omium.org>,
Matthias Kaehlcke <mka@...omium.org>
Subject: [PATCH v6 2/3] PM / devfreq: Don't adjust to user limits in governors
Several governors use the user space limits df->min/max_freq to adjust
the target frequency. This is not necessary, since update_devfreq()
already takes care of this. Instead the governor can request the available
min/max frequency by setting the target frequency to DEVFREQ_MIN/MAX_FREQ
and let update_devfreq() take care of any adjustments.
Signed-off-by: Matthias Kaehlcke <mka@...omium.org>
Reviewed-by: Brian Norris <briannorris@...omium.org>
Reviewed-by: Chanwoo Choi <cw00.choi@...sung.com>
---
Changes in v6:
- added 'Reviewed-by: Chanwoo Choi <cw00.choi@...sung.com>' tag
Changes in v5:
- none
Changes in v4:
- added 'Reviewed-by: Brian Norris <briannorris@...omium.org>' tag
Changes in v3:
- none
Changes in v2:
- squashed "PM / devfreq: Remove redundant frequency adjustment from governors"
and "PM / devfreq: governors: Return device frequency limits instead of user
limits"
- updated subject and commit message
- use DEVFREQ_MIN/MAX_FREQ instead of df->scaling_min/max_freq
---
drivers/devfreq/governor.h | 3 +++
drivers/devfreq/governor_performance.c | 5 +----
drivers/devfreq/governor_powersave.c | 2 +-
drivers/devfreq/governor_simpleondemand.c | 12 +++---------
drivers/devfreq/governor_userspace.c | 16 ++++------------
5 files changed, 12 insertions(+), 26 deletions(-)
diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h
index cfc50a61a90d..b81700244ce3 100644
--- a/drivers/devfreq/governor.h
+++ b/drivers/devfreq/governor.h
@@ -25,6 +25,9 @@
#define DEVFREQ_GOV_SUSPEND 0x4
#define DEVFREQ_GOV_RESUME 0x5
+#define DEVFREQ_MIN_FREQ 0
+#define DEVFREQ_MAX_FREQ ULONG_MAX
+
/**
* struct devfreq_governor - Devfreq policy governor
* @node: list node - contains registered devfreq governors
diff --git a/drivers/devfreq/governor_performance.c b/drivers/devfreq/governor_performance.c
index 4d23ecfbd948..ded429fd51be 100644
--- a/drivers/devfreq/governor_performance.c
+++ b/drivers/devfreq/governor_performance.c
@@ -20,10 +20,7 @@ static int devfreq_performance_func(struct devfreq *df,
* target callback should be able to get floor value as
* said in devfreq.h
*/
- if (!df->max_freq)
- *freq = UINT_MAX;
- else
- *freq = df->max_freq;
+ *freq = DEVFREQ_MAX_FREQ;
return 0;
}
diff --git a/drivers/devfreq/governor_powersave.c b/drivers/devfreq/governor_powersave.c
index 0c42f23249ef..9e8897f5ac42 100644
--- a/drivers/devfreq/governor_powersave.c
+++ b/drivers/devfreq/governor_powersave.c
@@ -20,7 +20,7 @@ static int devfreq_powersave_func(struct devfreq *df,
* target callback should be able to get ceiling value as
* said in devfreq.h
*/
- *freq = df->min_freq;
+ *freq = DEVFREQ_MIN_FREQ;
return 0;
}
diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
index 28e0f2de7100..c0417f0e081e 100644
--- a/drivers/devfreq/governor_simpleondemand.c
+++ b/drivers/devfreq/governor_simpleondemand.c
@@ -27,7 +27,6 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
unsigned int dfso_upthreshold = DFSO_UPTHRESHOLD;
unsigned int dfso_downdifferential = DFSO_DOWNDIFFERENCTIAL;
struct devfreq_simple_ondemand_data *data = df->data;
- unsigned long max = (df->max_freq) ? df->max_freq : UINT_MAX;
err = devfreq_update_stats(df);
if (err)
@@ -47,7 +46,7 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
/* Assume MAX if it is going to be divided by zero */
if (stat->total_time == 0) {
- *freq = max;
+ *freq = DEVFREQ_MAX_FREQ;
return 0;
}
@@ -60,13 +59,13 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
/* Set MAX if it's busy enough */
if (stat->busy_time * 100 >
stat->total_time * dfso_upthreshold) {
- *freq = max;
+ *freq = DEVFREQ_MAX_FREQ;
return 0;
}
/* Set MAX if we do not know the initial frequency */
if (stat->current_frequency == 0) {
- *freq = max;
+ *freq = DEVFREQ_MAX_FREQ;
return 0;
}
@@ -85,11 +84,6 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
b = div_u64(b, (dfso_upthreshold - dfso_downdifferential / 2));
*freq = (unsigned long) b;
- if (df->min_freq && *freq < df->min_freq)
- *freq = df->min_freq;
- if (df->max_freq && *freq > df->max_freq)
- *freq = df->max_freq;
-
return 0;
}
diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c
index 080607c3f34d..378d84c011df 100644
--- a/drivers/devfreq/governor_userspace.c
+++ b/drivers/devfreq/governor_userspace.c
@@ -26,19 +26,11 @@ static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq)
{
struct userspace_data *data = df->data;
- if (data->valid) {
- unsigned long adjusted_freq = data->user_frequency;
-
- if (df->max_freq && adjusted_freq > df->max_freq)
- adjusted_freq = df->max_freq;
-
- if (df->min_freq && adjusted_freq < df->min_freq)
- adjusted_freq = df->min_freq;
-
- *freq = adjusted_freq;
- } else {
+ if (data->valid)
+ *freq = data->user_frequency;
+ else
*freq = df->previous_freq; /* No user freq specified yet */
- }
+
return 0;
}
--
2.18.0.597.ga71716f1ad-goog
Powered by blists - more mailing lists