From mboxrd@z Thu Jan 1 00:00:00 1970 From: suzuki.poulose@arm.com (Suzuki K Poulose) Date: Thu, 19 Oct 2017 18:15:49 +0100 Subject: [PATCH 13/17] coresight etr: Do not clean ETR trace buffer In-Reply-To: <20171019171553.24056-1-suzuki.poulose@arm.com> References: <20171019171553.24056-1-suzuki.poulose@arm.com> Message-ID: <20171019171553.24056-14-suzuki.poulose@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org We zero out the entire trace buffer used for ETR before it is enabled, for helping with debugging. Since we could be restoring a session in perf mode, this could destroy the data. Get rid of this step, if someone wants to debug, they can always add it as and when needed. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose --- drivers/hwtracing/coresight/coresight-tmc-etr.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 31353fc34b53..849684f85443 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -971,8 +971,6 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata, return; drvdata->etr_buf = etr_buf; - /* Zero out the memory to help with debug */ - memset(etr_buf->vaddr, 0, etr_buf->size); CS_UNLOCK(drvdata->base); @@ -1267,9 +1265,8 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata) if (drvdata->mode == CS_MODE_SYSFS) { /* * The trace run will continue with the same allocated trace - * buffer. The trace buffer is cleared in tmc_etr_enable_hw(), - * so we don't have to explicitly clear it. Also, since the - * tracer is still enabled drvdata::buf can't be NULL. + * buffer. Since the tracer is still enabled drvdata::buf can't + * be NULL. */ tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf); } else { -- 2.13.6