From: Jia-Ju Bai <baijiaju1990@gmail.com>
To: vireshk@kernel.org, nm@ti.com, sboyd@codeaurora.org
Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [PATCH] opp: cpu: Replace GFP_ATOMIC with GFP_KERNEL in dev_pm_opp_init_cpufreq_table
Date: Fri, 26 Jan 2018 16:48:49 +0800 [thread overview]
Message-ID: <1516956529-32264-1-git-send-email-baijiaju1990@gmail.com> (raw)
After checking all possible call chains to
dev_pm_opp_init_cpufreq_table() here,
my tool finds that this function is never called in atomic context,
namely never in an interrupt handler or holding a spinlock.
And dev_pm_opp_init_cpufreq_table() calls dev_pm_opp_get_opp_count(),
which calls mutex_lock that can sleep.
It indicates that atmtcp_v_send() can call functions which may sleep.
Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL.
This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
drivers/opp/cpu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/opp/cpu.c b/drivers/opp/cpu.c
index 2d87bc1..0c09107 100644
--- a/drivers/opp/cpu.c
+++ b/drivers/opp/cpu.c
@@ -55,7 +55,7 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
if (max_opps <= 0)
return max_opps ? max_opps : -ENODATA;
- freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC);
+ freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL);
if (!freq_table)
return -ENOMEM;
--
1.7.9.5
next reply other threads:[~2018-01-26 8:44 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-26 8:48 Jia-Ju Bai [this message]
2018-02-08 14:45 ` [PATCH] opp: cpu: Replace GFP_ATOMIC with GFP_KERNEL in dev_pm_opp_init_cpufreq_table Viresh Kumar
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