Dzień dobry,
dostrzegam możliwość współpracy z Państwa firmą.
Świadczymy kompleksową obsługę inwestycji w fotowoltaikę, która obniża koszty energii elektrycznej nawet o 90%.
Czy są Państwo zainteresowani weryfikacją wstępnych propozycji?
Pozdrawiam,
Norbert Karecki
The use of kmap() is being deprecated in favor of kmap_local_page().
Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) kmap() also requires global TLB invalidation when the kmap’s pool
wraps and it might block when the mapping space is fully utilized until a
slot becomes available.
kmap_local_page() is preferred over kmap() and kmap_atomic(). Where it
cannot mechanically replace the latters, code refactor should be considered
(special care must be taken if kernel virtual addresses are aliases in
different contexts).
With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts).
Call kmap_local_page() in firmware_loader wherever kmap() is currently
used. In firmware_rw() use the helpers copy_{from,to}_page() instead of
open coding the local mappings + memcpy().
Successfully tested with "firmware" selftests on a QEMU/KVM 32-bits VM
with 4GB RAM, booting a kernel with HIGHMEM64GB enabled.
Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Cc: Luis Chamberlain <mcgrof(a)kernel.org>
Suggested-by: Ira Weiny <ira.weiny(a)intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco(a)gmail.com>
---
v1->v2: According to the comments from Greg Kroah-Hartman (thanks!),
extend the commit message adding information about why kmap() should be
avoided. Delete an unused variable left in the code of v1, which has been
Reported-by: kernel test robot <lkp(a)intel.com>
drivers/base/firmware_loader/main.c | 4 ++--
drivers/base/firmware_loader/sysfs.c | 10 ++++------
2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index ac3f34e80194..7c3590fd97c2 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -435,11 +435,11 @@ static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
/* decompress onto the new allocated page */
page = fw_priv->pages[fw_priv->nr_pages - 1];
- xz_buf.out = kmap(page);
+ xz_buf.out = kmap_local_page(page);
xz_buf.out_pos = 0;
xz_buf.out_size = PAGE_SIZE;
xz_ret = xz_dec_run(xz_dec, &xz_buf);
- kunmap(page);
+ kunmap_local(xz_buf.out);
fw_priv->size += xz_buf.out_pos;
/* partial decompression means either end or error */
if (xz_buf.out_pos != PAGE_SIZE)
diff --git a/drivers/base/firmware_loader/sysfs.c b/drivers/base/firmware_loader/sysfs.c
index 5b0b85b70b6f..77bad32c481a 100644
--- a/drivers/base/firmware_loader/sysfs.c
+++ b/drivers/base/firmware_loader/sysfs.c
@@ -242,19 +242,17 @@ static void firmware_rw(struct fw_priv *fw_priv, char *buffer,
loff_t offset, size_t count, bool read)
{
while (count) {
- void *page_data;
int page_nr = offset >> PAGE_SHIFT;
int page_ofs = offset & (PAGE_SIZE - 1);
int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
- page_data = kmap(fw_priv->pages[page_nr]);
-
if (read)
- memcpy(buffer, page_data + page_ofs, page_cnt);
+ memcpy_from_page(buffer, fw_priv->pages[page_nr],
+ page_ofs, page_cnt);
else
- memcpy(page_data + page_ofs, buffer, page_cnt);
+ memcpy_to_page(fw_priv->pages[page_nr], page_ofs,
+ buffer, page_cnt);
- kunmap(fw_priv->pages[page_nr]);
buffer += page_cnt;
offset += page_cnt;
count -= page_cnt;
--
2.37.0
Add a new QEMU config for kunit_tool, x86_64-smp, which provides an
8-cpu SMP setup. No other kunit_tool configurations provide an SMP
setup, so this is the best bet for testing things like KCSAN, which
require a multicore/multi-cpu system.
The choice of 8 CPUs is pretty arbitrary: it's enough to get tests like
KCSAN to run with a nontrivial number of worker threads, while still
working relatively quickly on older machines.
Signed-off-by: David Gow <davidgow(a)google.com>
---
This is based off the discussion in:
https://groups.google.com/g/kasan-dev/c/A7XzC2pXRC8
---
tools/testing/kunit/qemu_configs/x86_64-smp.py | 13 +++++++++++++
1 file changed, 13 insertions(+)
create mode 100644 tools/testing/kunit/qemu_configs/x86_64-smp.py
diff --git a/tools/testing/kunit/qemu_configs/x86_64-smp.py b/tools/testing/kunit/qemu_configs/x86_64-smp.py
new file mode 100644
index 000000000000..a95623f5f8b7
--- /dev/null
+++ b/tools/testing/kunit/qemu_configs/x86_64-smp.py
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0
+from ..qemu_config import QemuArchParams
+
+QEMU_ARCH = QemuArchParams(linux_arch='x86_64',
+ kconfig='''
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SMP=y
+ ''',
+ qemu_arch='x86_64',
+ kernel_path='arch/x86/boot/bzImage',
+ kernel_command_line='console=ttyS0',
+ extra_qemu_params=['-smp', '8'])
--
2.36.0.550.gb090851708-goog
The timer selftests are quite useful for me when enabling timers on new
SoCs, e.g. like now with the CMT timer on a Renesas R-Car S4-8. During
development, I needed these fixes and additions to make full use of
the tests. I think they make all sense upstream, so here they are.
Patches are based on v5.19-rc1. Looking forward to comments.
Happy hacking,
Wolfram
Wolfram Sang (9):
selftests: timers: valid-adjtimex: build fix for newer toolchains
selftests: timers: fix declarations of main()
selftests: timers: nanosleep: adapt to kselftest framework
selftests: timers: inconsistency-check: adapt to kselftest framework
selftests: timers: clocksource-switch: fix passing errors from child
selftests: timers: clocksource-switch: sort includes
selftests: timers: clocksource-switch: add command line switch to skip
sanity check
selftests: timers: clocksource-switch: add 'runtime' command line
parameter
selftests: timers: clocksource-switch: adapt to kselftest framework
tools/testing/selftests/timers/adjtick.c | 2 +-
tools/testing/selftests/timers/change_skew.c | 2 +-
.../selftests/timers/clocksource-switch.c | 70 ++++++++++++-------
.../selftests/timers/inconsistency-check.c | 32 +++++----
tools/testing/selftests/timers/nanosleep.c | 18 +++--
tools/testing/selftests/timers/raw_skew.c | 2 +-
.../selftests/timers/skew_consistency.c | 2 +-
.../testing/selftests/timers/valid-adjtimex.c | 2 +-
8 files changed, 80 insertions(+), 50 deletions(-)
--
2.35.1