| Message ID | a09beb635bafcdb804127f100dc4337f2b536521.1486553361.git.joe@perches.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/08/2017 06:33 AM, Joe Perches wrote: > This function error patch can be simplified, so do so. > > Remove fail: label and somewhat obfuscating, used once "error_path" > function. > > Signed-off-by: Joe Perches <joe@perches.com> Applied to for-linus-4.11. -boris
On Wed, 2017-02-08 at 10:33 -0500, Boris Ostrovsky wrote: > On 02/08/2017 06:33 AM, Joe Perches wrote: > > This function error patch can be simplified, so do so. > > > > Remove fail: label and somewhat obfuscating, used once "error_path" > > function. btw: I left it alone, but likely #define PRINTF_BUFFER_SIZE 4096 is probably excessive as the maximum printk buffer is 1024. The xenbus_write might be longer though so maybe it's OK to use 4096, but there is some inequivalence there.
On 02/08/2017 11:05 AM, Joe Perches wrote: > On Wed, 2017-02-08 at 10:33 -0500, Boris Ostrovsky wrote: >> On 02/08/2017 06:33 AM, Joe Perches wrote: >>> This function error patch can be simplified, so do so. >>> >>> Remove fail: label and somewhat obfuscating, used once "error_path" >>> function. > btw: I left it alone, but likely > > #define PRINTF_BUFFER_SIZE 4096 > > is probably excessive as the maximum printk > buffer is 1024. > > The xenbus_write might be longer though so > maybe it's OK to use 4096, but there is some > inequivalence there. > xenbus_write() handles writes up to 4K. However we are filling the buffer with sprintf() which I assume is limited to 1K too so it indeed doesn't seem useful to have PRINTF_BUFFER_SIZE set to 4. -boris
On Wed, 2017-02-08 at 12:14 -0500, Boris Ostrovsky wrote: > On 02/08/2017 11:05 AM, Joe Perches wrote: > > On Wed, 2017-02-08 at 10:33 -0500, Boris Ostrovsky wrote: > > > On 02/08/2017 06:33 AM, Joe Perches wrote: > > > > This function error patch can be simplified, so do so. > > > > > > > > Remove fail: label and somewhat obfuscating, used once "error_path" > > > > function. > > > > btw: I left it alone, but likely > > > > #define PRINTF_BUFFER_SIZE 4096 > > > > is probably excessive as the maximum printk > > buffer is 1024. > > > > The xenbus_write might be longer though so > > maybe it's OK to use 4096, but there is some > > inequivalence there. > > > > xenbus_write() handles writes up to 4K. However we are filling the > buffer with sprintf() which I assume is limited to 1K too vsnprintf is bounded only by addressable memory. ie: (void *)-1 > so it indeed > doesn't seem useful to have PRINTF_BUFFER_SIZE set to 4. > > -boris >
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c index 056da6ee1a35..915d77785193 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -259,53 +259,34 @@ int xenbus_frontend_closed(struct xenbus_device *dev) } EXPORT_SYMBOL_GPL(xenbus_frontend_closed); -/** - * Return the path to the error node for the given device, or NULL on failure. - * If the value returned is non-NULL, then it is the caller's to kfree. - */ -static char *error_path(struct xenbus_device *dev) -{ - return kasprintf(GFP_KERNEL, "error/%s", dev->nodename); -} - - static void xenbus_va_dev_error(struct xenbus_device *dev, int err, const char *fmt, va_list ap) { unsigned int len; - char *printf_buffer = NULL; - char *path_buffer = NULL; + char *printf_buffer; + char *path_buffer; #define PRINTF_BUFFER_SIZE 4096 + printf_buffer = kmalloc(PRINTF_BUFFER_SIZE, GFP_KERNEL); - if (printf_buffer == NULL) - goto fail; + if (!printf_buffer) + return; len = sprintf(printf_buffer, "%i ", -err); - vsnprintf(printf_buffer+len, PRINTF_BUFFER_SIZE-len, fmt, ap); + vsnprintf(printf_buffer + len, PRINTF_BUFFER_SIZE - len, fmt, ap); dev_err(&dev->dev, "%s\n", printf_buffer); - path_buffer = error_path(dev); - - if (path_buffer == NULL) { + path_buffer = kasprintf(GFP_KERNEL, "error/%s", dev->nodename); + if (!path_buffer || + xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer)) dev_err(&dev->dev, "failed to write error node for %s (%s)\n", - dev->nodename, printf_buffer); - goto fail; - } + dev->nodename, printf_buffer); - if (xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer) != 0) { - dev_err(&dev->dev, "failed to write error node for %s (%s)\n", - dev->nodename, printf_buffer); - goto fail; - } - -fail: kfree(printf_buffer); kfree(path_buffer); } - /** * xenbus_dev_error * @dev: xenbus device
This function error patch can be simplified, so do so. Remove fail: label and somewhat obfuscating, used once "error_path" function. Signed-off-by: Joe Perches <joe@perches.com> --- drivers/xen/xenbus/xenbus_client.c | 39 ++++++++++---------------------------- 1 file changed, 10 insertions(+), 29 deletions(-)