2023-10-12 11:08:54

by Mao Jinlong

[permalink] [raw]
Subject: [PATCH] coresight-tmc-etr: Fix busy error when enable multiple sources

In enable sink sysfs function, when etr is enabled, it doesn't need
to call enable hw function again.

[ 91.057233] ------------[ cut here ]------------
[ 91.061983] WARNING: CPU: 6 PID: 145 at drivers/hwtracing/coresight/coresight-tmc-etr.c:1038 tmc_etr_enable_hw+0xc4/0xd0
[ 91.073153] Modules linked in:
[ 91.076302] CPU: 6 PID: 145 Comm: sh Tainted: G S W 6.5.0-rc3-g66d5eaa9e5a7 #111
[ 91.085149] Hardware name: Qualcomm Technologies, Inc. SM8450 QRD (DT)
[ 91.091847] pstate: 634000c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
[ 91.099000] pc : tmc_etr_enable_hw+0xc4/0xd0
[ 91.103389] lr : tmc_enable_etr_sink+0x13c/0x294
[ 91.108130] sp : ffff8000815cbb30
[ 91.111537] x29: ffff8000815cbb30 x28: ffff68ce4352a800 x27: 0000000000000000
[ 91.118868] x26: ffff68ce414cc040 x25: ffff68ce414a82e0 x24: 0000000000000000
[ 91.126199] x23: ffff68ce423a1ee0 x22: ffff68ce423a1e80 x21: ffff68ce4352a800
[ 91.133527] x20: 0000000000000001 x19: ffff68ce414aa500 x18: fffffda31cf9c008
[ 91.140857] x17: 0000000000000040 x16: 0000000000000001 x15: fffffc0000000000
[ 91.148188] x14: 00000000f0000080 x13: 0000000000000000 x12: ffff9739c0000000
[ 91.155516] x11: ffffbe9cdf71e400 x10: 0000000000001000 x9 : ffff68d0b29e3b28
[ 91.162845] x8 : fffffda31cf983c8 x7 : fffffda31cf98388 x6 : 00000000ffffffd0
[ 91.170174] x5 : ffff68ce435d8ec0 x4 : ffff68d0b29e2610 x3 : ffff68ce435d8ec0
[ 91.177502] x2 : ffff68ce414aa500 x1 : ffff68ce414aa500 x0 : ffff68ce423a1e80
[ 91.184833] Call trace:
[ 91.187349] tmc_etr_enable_hw+0xc4/0xd0
[ 91.191388] tmc_enable_etr_sink+0x13c/0x294
[ 91.195777] coresight_enable_path+0x21c/0x24c
[ 91.200347] coresight_enable+0x9c/0x204
[ 91.204379] enable_source_store+0x58/0xa0
[ 91.208595] dev_attr_store+0x18/0x2c
[ 91.212361] sysfs_kf_write+0x40/0x54
[ 91.216126] kernfs_fop_write_iter+0x164/0x1dc
[ 91.220692] vfs_write+0x3a8/0x460
[ 91.224191] ksys_write+0x6c/0x100
[ 91.227690] __arm64_sys_write+0x1c/0x28
[ 91.231728] invoke_syscall+0x44/0x100
[ 91.235586] el0_svc_common.constprop.1+0x6c/0xe4
[ 91.240418] do_el0_svc+0x38/0x94
[ 91.243833] el0_svc+0x28/0x74
[ 91.246981] el0t_64_sync_handler+0xa0/0xc4
[ 91.251282] el0t_64_sync+0x174/0x178
[ 91.255045] ---[ end trace 0000000000000000 ]---
sh: write error: Device or resource busy

Signed-off-by: Mao Jinlong <[email protected]>
---
drivers/hwtracing/coresight/coresight-tmc-etr.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 66dc5f97a009..e1c7bae9f6ee 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -1204,7 +1204,7 @@ static struct etr_buf *tmc_etr_get_sysfs_buffer(struct coresight_device *csdev)

static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
{
- int ret;
+ int ret = 0;
unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct etr_buf *sysfs_buf = tmc_etr_get_sysfs_buffer(csdev);
@@ -1213,12 +1213,16 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
return PTR_ERR(sysfs_buf);

spin_lock_irqsave(&drvdata->spinlock, flags);
+ if (drvdata->mode == CS_MODE_SYSFS)
+ goto out;
+
ret = tmc_etr_enable_hw(drvdata, sysfs_buf);
if (!ret) {
drvdata->mode = CS_MODE_SYSFS;
atomic_inc(&csdev->refcnt);
}

+out:
spin_unlock_irqrestore(&drvdata->spinlock, flags);

if (!ret)
--
2.17.1


2023-10-12 11:12:14

by Suzuki K Poulose

[permalink] [raw]
Subject: Re: [PATCH] coresight-tmc-etr: Fix busy error when enable multiple sources

On 12/10/2023 12:07, Mao Jinlong wrote:
> In enable sink sysfs function, when etr is enabled, it doesn't need
> to call enable hw function again.
>
> [ 91.057233] ------------[ cut here ]------------
> [ 91.061983] WARNING: CPU: 6 PID: 145 at drivers/hwtracing/coresight/coresight-tmc-etr.c:1038 tmc_etr_enable_hw+0xc4/0xd0
> [ 91.073153] Modules linked in:
> [ 91.076302] CPU: 6 PID: 145 Comm: sh Tainted: G S W 6.5.0-rc3-g66d5eaa9e5a7 #111
> [ 91.085149] Hardware name: Qualcomm Technologies, Inc. SM8450 QRD (DT)
> [ 91.091847] pstate: 634000c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
> [ 91.099000] pc : tmc_etr_enable_hw+0xc4/0xd0
> [ 91.103389] lr : tmc_enable_etr_sink+0x13c/0x294
> [ 91.108130] sp : ffff8000815cbb30
> [ 91.111537] x29: ffff8000815cbb30 x28: ffff68ce4352a800 x27: 0000000000000000
> [ 91.118868] x26: ffff68ce414cc040 x25: ffff68ce414a82e0 x24: 0000000000000000
> [ 91.126199] x23: ffff68ce423a1ee0 x22: ffff68ce423a1e80 x21: ffff68ce4352a800
> [ 91.133527] x20: 0000000000000001 x19: ffff68ce414aa500 x18: fffffda31cf9c008
> [ 91.140857] x17: 0000000000000040 x16: 0000000000000001 x15: fffffc0000000000
> [ 91.148188] x14: 00000000f0000080 x13: 0000000000000000 x12: ffff9739c0000000
> [ 91.155516] x11: ffffbe9cdf71e400 x10: 0000000000001000 x9 : ffff68d0b29e3b28
> [ 91.162845] x8 : fffffda31cf983c8 x7 : fffffda31cf98388 x6 : 00000000ffffffd0
> [ 91.170174] x5 : ffff68ce435d8ec0 x4 : ffff68d0b29e2610 x3 : ffff68ce435d8ec0
> [ 91.177502] x2 : ffff68ce414aa500 x1 : ffff68ce414aa500 x0 : ffff68ce423a1e80
> [ 91.184833] Call trace:
> [ 91.187349] tmc_etr_enable_hw+0xc4/0xd0
> [ 91.191388] tmc_enable_etr_sink+0x13c/0x294
> [ 91.195777] coresight_enable_path+0x21c/0x24c
> [ 91.200347] coresight_enable+0x9c/0x204
> [ 91.204379] enable_source_store+0x58/0xa0
> [ 91.208595] dev_attr_store+0x18/0x2c
> [ 91.212361] sysfs_kf_write+0x40/0x54
> [ 91.216126] kernfs_fop_write_iter+0x164/0x1dc
> [ 91.220692] vfs_write+0x3a8/0x460
> [ 91.224191] ksys_write+0x6c/0x100
> [ 91.227690] __arm64_sys_write+0x1c/0x28
> [ 91.231728] invoke_syscall+0x44/0x100
> [ 91.235586] el0_svc_common.constprop.1+0x6c/0xe4
> [ 91.240418] do_el0_svc+0x38/0x94
> [ 91.243833] el0_svc+0x28/0x74
> [ 91.246981] el0t_64_sync_handler+0xa0/0xc4
> [ 91.251282] el0t_64_sync+0x174/0x178
> [ 91.255045] ---[ end trace 0000000000000000 ]---
> sh: write error: Device or resource busy
>

Please could you try this patch ?

https://lore.kernel.org/r/[email protected]

It is queued in Greg's tree for v6.6, hopefully it will hit -rc6.

Suzuki


> Signed-off-by: Mao Jinlong <[email protected]>
> ---
> drivers/hwtracing/coresight/coresight-tmc-etr.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
> index 66dc5f97a009..e1c7bae9f6ee 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
> +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
> @@ -1204,7 +1204,7 @@ static struct etr_buf *tmc_etr_get_sysfs_buffer(struct coresight_device *csdev)
>
> static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
> {
> - int ret;
> + int ret = 0;
> unsigned long flags;
> struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> struct etr_buf *sysfs_buf = tmc_etr_get_sysfs_buffer(csdev);
> @@ -1213,12 +1213,16 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
> return PTR_ERR(sysfs_buf);
>
> spin_lock_irqsave(&drvdata->spinlock, flags);
> + if (drvdata->mode == CS_MODE_SYSFS)
> + goto out;
> +
> ret = tmc_etr_enable_hw(drvdata, sysfs_buf);
> if (!ret) {
> drvdata->mode = CS_MODE_SYSFS;
> atomic_inc(&csdev->refcnt);
> }
>
> +out:
> spin_unlock_irqrestore(&drvdata->spinlock, flags);
>
> if (!ret)