diff options
author | Matwey V. Kornilov <matwey@sai.msu.ru> | 2018-11-09 20:03:26 +0100 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2019-01-16 17:15:11 +0100 |
commit | c1d5fb019f65e1093c77734356f97b6e7ac4d629 (patch) | |
tree | 547851420ab5c4a9d254417f0661336139adae13 /drivers/media/usb | |
parent | media: s5p-mfc: fix incorrect bus assignment in virtual child device (diff) | |
download | linux-c1d5fb019f65e1093c77734356f97b6e7ac4d629.tar.xz linux-c1d5fb019f65e1093c77734356f97b6e7ac4d629.zip |
media: usb: pwc: Introduce TRACE_EVENTs for pwc_isoc_handler()
There were reports that PWC-based webcams don't work at some
embedded ARM platforms. [1] Isochronous transfer handler seems to
work too long leading to the issues in MUSB USB host subsystem.
Also note, that urb->giveback() handlers are still called with
disabled interrupts. In order to be able to measure performance of
PWC driver, traces are introduced in URB handler section.
[1] https://www.spinics.net/lists/linux-usb/msg165735.html
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'drivers/media/usb')
-rw-r--r-- | drivers/media/usb/pwc/pwc-if.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/media/usb/pwc/pwc-if.c b/drivers/media/usb/pwc/pwc-if.c index 72704f4d5330..53c111bd5a22 100644 --- a/drivers/media/usb/pwc/pwc-if.c +++ b/drivers/media/usb/pwc/pwc-if.c @@ -76,6 +76,9 @@ #include "pwc-dec23.h" #include "pwc-dec1.h" +#define CREATE_TRACE_POINTS +#include <trace/events/pwc.h> + /* Function prototypes and driver templates */ /* hotplug device table support */ @@ -260,6 +263,8 @@ static void pwc_isoc_handler(struct urb *urb) int i, fst, flen; unsigned char *iso_buf = NULL; + trace_pwc_handler_enter(urb, pdev); + if (urb->status == -ENOENT || urb->status == -ECONNRESET || urb->status == -ESHUTDOWN) { PWC_DEBUG_OPEN("URB (%p) unlinked %ssynchronously.\n", @@ -348,6 +353,8 @@ static void pwc_isoc_handler(struct urb *urb) } handler_end: + trace_pwc_handler_exit(urb, pdev); + i = usb_submit_urb(urb, GFP_ATOMIC); if (i != 0) PWC_ERROR("Error (%d) re-submitting urb in pwc_isoc_handler.\n", i); |