From: Andrew Murray <andrew.murray@arm.com>
To: Mathieu Poirier <mathieu.poirier@linaro.org>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: coresight@lists.linaro.org, Sudeep Holla <sudeep.holla@arm.com>,
Leo Yan <leo.yan@linaro.org>,
linux-arm-kernel@lists.infradead.org,
Mike Leach <mike.leach@linaro.org>
Subject: [PATCH] coresight: etm4x: lazily allocate memory for save_state
Date: Fri, 12 Jul 2019 16:00:56 +0100 [thread overview]
Message-ID: <20190712150056.15775-1-andrew.murray@arm.com> (raw)
In-Reply-To: <20190711160114.634-6-andrew.murray@arm.com>
I had intended to lazily allocate memory for the save_state structure when
it is first used. Following is a patch that I will squash into "[PATCH v3 5/6]
coresight: etm4x: save/restore state across CPU low power states" on my
next respin. I thought I'd share it here to get some feedback along with
the rest of v3.
Thanks,
Andrew Murray
---
drivers/hwtracing/coresight/coresight-etm4x.c | 14 +++++++++++---
drivers/hwtracing/coresight/coresight-etm4x.h | 2 +-
2 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index b0bd8158bf13..cd02372194bc 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -1112,6 +1112,13 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
struct etmv4_save_state *state;
struct device *etm_dev = &drvdata->csdev->dev;
+ if (!drvdata->save_state) {
+ drvdata->save_state = devm_kmalloc(etm_dev,
+ sizeof(struct etmv4_save_state), GFP_KERNEL);
+ if (!drvdata->save_state)
+ return -ENOMEM;
+ }
+
/*
* As recommended by 3.4.1 ("The procedure when powering down the PE")
* of ARM IHI 0064D
@@ -1134,7 +1141,7 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
goto out;
}
- state = &drvdata->save_state;
+ state = drvdata->save_state;
state->trcprgctlr = readl(drvdata->base + TRCPRGCTLR);
state->trcprocselr = readl(drvdata->base + TRCPROCSELR);
@@ -1234,9 +1241,10 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
{
int i;
- struct etmv4_save_state *state;
+ struct etmv4_save_state *state = drvdata->save_state;
- state = &drvdata->save_state;
+ if (WARN_ON_ONCE(!state))
+ return;
CS_UNLOCK(drvdata->base);
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
index c31634c64f87..a70cafbbb8cf 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.h
+++ b/drivers/hwtracing/coresight/coresight-etm4x.h
@@ -441,7 +441,7 @@ struct etmv4_drvdata {
bool atbtrig;
bool lpoverride;
struct etmv4_config config;
- struct etmv4_save_state save_state;
+ struct etmv4_save_state *save_state;
bool state_needs_restore;
};
--
2.21.0
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next prev parent reply other threads:[~2019-07-12 15:02 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-11 16:01 [PATCH v3 0/6] coresight: etm4x: save/restore ETMv4 context across CPU low power states Andrew Murray
2019-07-11 16:01 ` [PATCH v3 1/6] coresight: etm4x: remove superfluous setting of os_unlock Andrew Murray
2019-07-11 16:01 ` [PATCH v3 2/6] coresight: etm4x: use explicit barriers on enable/disable Andrew Murray
2019-07-11 16:01 ` [PATCH v3 3/6] coresight: etm4x: use module_param instead of module_param_named Andrew Murray
2019-07-11 16:01 ` [PATCH v3 4/6] coresight: etm4x: improve clarity of etm4_os_unlock comment Andrew Murray
2019-07-11 16:01 ` [PATCH v3 5/6] coresight: etm4x: save/restore state across CPU low power states Andrew Murray
2019-07-12 15:00 ` Andrew Murray [this message]
2019-07-22 20:32 ` [PATCH] coresight: etm4x: lazily allocate memory for save_state Mathieu Poirier
2019-07-23 9:05 ` Suzuki K Poulose
2019-07-26 11:24 ` Andrew Murray
2019-07-30 10:15 ` Suzuki K Poulose
2019-07-15 14:22 ` [PATCH v3 5/6] coresight: etm4x: save/restore state across CPU low power states Mike Leach
2019-07-16 11:50 ` Andrew Murray
2019-07-16 14:43 ` Mike Leach
2019-07-15 23:04 ` Mathieu Poirier
2019-07-16 11:52 ` Andrew Murray
2019-07-11 16:01 ` [PATCH v3 6/6] dt-bindings: arm: coresight: Add support for coresight-needs-save-restore Andrew Murray
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