On Mon 28 Sep 17:17 CDT 2020, Rishabh Bhatnagar wrote:
> Move coredump configuration from debugfs to sysfs.This will
> allow usage of this configuration feature in production
> devices where access to debugfs might be limited.
>
> Signed-off-by: Rishabh Bhatnagar <rishabhb@xxxxxxxxxxxxxx>
I like the end result of this series now Rishabh, but...
> ---
> Documentation/ABI/testing/sysfs-class-remoteproc | 24 +++++++
> drivers/remoteproc/remoteproc_debugfs.c | 90 ------------------------
> drivers/remoteproc/remoteproc_sysfs.c | 64 +++++++++++++++++
> 3 files changed, 88 insertions(+), 90 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-class-remoteproc b/Documentation/ABI/testing/sysfs-class-remoteproc
> index 36094fb..f6c44fa 100644
> --- a/Documentation/ABI/testing/sysfs-class-remoteproc
> +++ b/Documentation/ABI/testing/sysfs-class-remoteproc
> @@ -58,3 +58,27 @@ Description: Remote processor name
> Reports the name of the remote processor. This can be used by
> userspace in exactly identifying a remote processor and ease
> up the usage in modifying the 'firmware' or 'state' files.
> +
> +What: /sys/class/remoteproc/.../coredump
> +Date: July 2020
> +Contact: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>, Ohad Ben-Cohen <ohad@xxxxxxxxxx>
> +Description: Remote processor coredump configuration
> +
> + Reports the coredump configuration of the remote processor,
> + which will be one of:
> +
> + "default"
...can you please make this "enabled" already here, so that patch 3
doesn't touch the definition of the sysfs. That way we don't introduce a
new sysfs attribute and immediately change it.
Please keep the remainder (rename of defines etc) in patch 3 as is - I
just want the string exposed to userspace to be consistent here.
(Or if you find the end result, you can move patch 3 before this change
in the series)
Regards,
Bjorn
> + "inline"
> + "disabled"
> +
> + "default" means when the remote processor's coredump is
> + collected it will be copied to a separate buffer and that
> + buffer is exposed to userspace.
> +
> + "inline" means when the remote processor's coredump is
> + collected userspace will directly read from the remote
> + processor's device memory. Extra buffer will not be used to
> + copy the dump. Also recovery process will not proceed until
> + all data is read by usersapce.
> +
> + "disabled" means no dump will be collected.
> diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
> index 2e3b3e2..732770e 100644
> --- a/drivers/remoteproc/remoteproc_debugfs.c
> +++ b/drivers/remoteproc/remoteproc_debugfs.c
> @@ -28,94 +28,6 @@
> static struct dentry *rproc_dbg;
>
> /*
> - * A coredump-configuration-to-string lookup table, for exposing a
> - * human readable configuration via debugfs. Always keep in sync with
> - * enum rproc_coredump_mechanism
> - */
> -static const char * const rproc_coredump_str[] = {
> - [RPROC_COREDUMP_DEFAULT] = "default",
> - [RPROC_COREDUMP_INLINE] = "inline",
> - [RPROC_COREDUMP_DISABLED] = "disabled",
> -};
> -
> -/* Expose the current coredump configuration via debugfs */
> -static ssize_t rproc_coredump_read(struct file *filp, char __user *userbuf,
> - size_t count, loff_t *ppos)
> -{
> - struct rproc *rproc = filp->private_data;
> - char buf[20];
> - int len;
> -
> - len = scnprintf(buf, sizeof(buf), "%s\n",
> - rproc_coredump_str[rproc->dump_conf]);
> -
> - return simple_read_from_buffer(userbuf, count, ppos, buf, len);
> -}
> -
> -/*
> - * By writing to the 'coredump' debugfs entry, we control the behavior of the
> - * coredump mechanism dynamically. The default value of this entry is "default".
> - *
> - * The 'coredump' debugfs entry supports these commands:
> - *
> - * default: This is the default coredump mechanism. When the remoteproc
> - * crashes the entire coredump will be copied to a separate buffer
> - * and exposed to userspace.
> - *
> - * inline: The coredump will not be copied to a separate buffer and the
> - * recovery process will have to wait until data is read by
> - * userspace. But this avoid usage of extra memory.
> - *
> - * disabled: This will disable coredump. Recovery will proceed without
> - * collecting any dump.
> - */
> -static ssize_t rproc_coredump_write(struct file *filp,
> - const char __user *user_buf, size_t count,
> - loff_t *ppos)
> -{
> - struct rproc *rproc = filp->private_data;
> - int ret, err = 0;
> - char buf[20];
> -
> - if (count > sizeof(buf))
> - return -EINVAL;
> -
> - ret = copy_from_user(buf, user_buf, count);
> - if (ret)
> - return -EFAULT;
> -
> - /* remove end of line */
> - if (buf[count - 1] == '\n')
> - buf[count - 1] = '\0';
> -
> - if (rproc->state == RPROC_CRASHED) {
> - dev_err(&rproc->dev, "can't change coredump configuration\n");
> - err = -EBUSY;
> - goto out;
> - }
> -
> - if (!strncmp(buf, "disable", count)) {
> - rproc->dump_conf = RPROC_COREDUMP_DISABLED;
> - } else if (!strncmp(buf, "inline", count)) {
> - rproc->dump_conf = RPROC_COREDUMP_INLINE;
> - } else if (!strncmp(buf, "default", count)) {
> - rproc->dump_conf = RPROC_COREDUMP_DEFAULT;
> - } else {
> - dev_err(&rproc->dev, "Invalid coredump configuration\n");
> - err = -EINVAL;
> - }
> -out:
> - return err ? err : count;
> -}
> -
> -static const struct file_operations rproc_coredump_fops = {
> - .read = rproc_coredump_read,
> - .write = rproc_coredump_write,
> - .open = simple_open,
> - .llseek = generic_file_llseek,
> -};
> -
> -/*
> * Some remote processors may support dumping trace logs into a shared
> * memory buffer. We expose this trace buffer using debugfs, so users
> * can easily tell what's going on remotely.
> @@ -425,8 +337,6 @@ void rproc_create_debug_dir(struct rproc *rproc)
> rproc, &rproc_rsc_table_fops);
> debugfs_create_file("carveout_memories", 0400, rproc->dbg_dir,
> rproc, &rproc_carveouts_fops);
> - debugfs_create_file("coredump", 0600, rproc->dbg_dir,
> - rproc, &rproc_coredump_fops);
> }
>
> void __init rproc_init_debugfs(void)
> diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
> index eea514c..2a44571 100644
> --- a/drivers/remoteproc/remoteproc_sysfs.c
> +++ b/drivers/remoteproc/remoteproc_sysfs.c
> @@ -10,6 +10,69 @@
>
> #define to_rproc(d) container_of(d, struct rproc, dev)
>
> +/*
> + * A coredump-configuration-to-string lookup table, for exposing a
> + * human readable configuration via sysfs. Always keep in sync with
> + * enum rproc_coredump_mechanism
> + */
> +static const char * const rproc_coredump_str[] = {
> + [RPROC_COREDUMP_DEFAULT] = "default",
> + [RPROC_COREDUMP_INLINE] = "inline",
> + [RPROC_COREDUMP_DISABLED] = "disabled",
> +};
> +
> +/* Expose the current coredump configuration via debugfs */
> +static ssize_t coredump_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct rproc *rproc = to_rproc(dev);
> +
> + return sprintf(buf, "%s\n", rproc_coredump_str[rproc->dump_conf]);
> +}
> +
> +/*
> + * By writing to the 'coredump' sysfs entry, we control the behavior of the
> + * coredump mechanism dynamically. The default value of this entry is "default".
> + *
> + * The 'coredump' sysfs entry supports these commands:
> + *
> + * default: This is the default coredump mechanism. When the remoteproc
> + * crashes the entire coredump will be copied to a separate buffer
> + * and exposed to userspace.
> + *
> + * inline: The coredump will not be copied to a separate buffer and the
> + * recovery process will have to wait until data is read by
> + * userspace. But this avoid usage of extra memory.
> + *
> + * disabled: This will disable coredump. Recovery will proceed without
> + * collecting any dump.
> + */
> +static ssize_t coredump_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct rproc *rproc = to_rproc(dev);
> +
> + if (rproc->state == RPROC_CRASHED) {
> + dev_err(&rproc->dev, "can't change coredump configuration\n");
> + return -EBUSY;
> + }
> +
> + if (sysfs_streq(buf, "disabled")) {
> + rproc->dump_conf = RPROC_COREDUMP_DISABLED;
> + } else if (sysfs_streq(buf, "inline")) {
> + rproc->dump_conf = RPROC_COREDUMP_INLINE;
> + } else if (sysfs_streq(buf, "default")) {
> + rproc->dump_conf = RPROC_COREDUMP_DEFAULT;
> + } else {
> + dev_err(&rproc->dev, "Invalid coredump configuration\n");
> + return -EINVAL;
> + }
> +
> + return count;
> +}
> +static DEVICE_ATTR_RW(coredump);
> +
> /* Expose the loaded / running firmware name via sysfs */
> static ssize_t firmware_show(struct device *dev, struct device_attribute *attr,
> char *buf)
> @@ -138,6 +201,7 @@ static ssize_t name_show(struct device *dev, struct device_attribute *attr,
> static DEVICE_ATTR_RO(name);
>
> static struct attribute *rproc_attrs[] = {
> + &dev_attr_coredump.attr,
> &dev_attr_firmware.attr,
> &dev_attr_state.attr,
> &dev_attr_name.attr,
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
