linux/drivers/hwtracing/intel_th
Alexander Shishkin f505e91ef5 intel_th: msu: Start read iterator from a non-empty window
In multi-window mode, the read iterator is supposed to start from the
window with the oldest data, which is, chronologically, the next window
after the one with the newest data. This, however, fails to take into
account the potentially empty windows, so in short trace sessions it's
possible to have a lot of zeroes read from the character device first.

Fix this by skipping over the empty windows in initialization of the
read iterator.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20190627125152.54905-5-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03 17:45:57 +02:00
..
acpi.c intel_th: Communicate IRQ via resource 2019-05-03 18:14:29 +02:00
core.c intel_th: Add switch triggering support 2019-05-03 18:16:21 +02:00
debug.c intel_th: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate 2018-03-28 18:47:19 +03:00
debug.h intel_th: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate 2018-03-28 18:47:19 +03:00
gth.c intel_th: Add switch triggering support 2019-05-03 18:16:21 +02:00
gth.h intel_th: Add switch triggering support 2019-05-03 18:16:21 +02:00
intel_th.h intel_th: Add switch triggering support 2019-05-03 18:16:21 +02:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile intel_th: Add ACPI glue layer 2018-03-28 18:47:23 +03:00
msu.c intel_th: msu: Start read iterator from a non-empty window 2019-07-03 17:45:57 +02:00
msu.h intel_th: msu: Correct the block wrap detection 2019-05-03 18:16:21 +02:00
pci.c intel_th: pci: Add Ice Lake NNPI support 2019-07-03 17:36:43 +02:00
pti.c intel_th: pti: Use sysfs_match_string() helper 2019-02-21 15:04:36 +02:00
pti.h intel_th: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate 2018-03-28 18:47:19 +03:00
sth.c intel_th: Mark expected switch fall-throughs 2019-02-21 15:04:36 +02:00
sth.h intel_th: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate 2018-03-28 18:47:19 +03:00