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Currently, internals of dma_common_mmap() is compiled out if build is
done for either NOMMU or target which explicitly says it does not
have/want coherent DMA mmap. It turned out that dma_common_mmap() can
be handy in NOMMU setup (at least for ARM).
This patch converts exitent NOMMU targets to use ARCH_NO_COHERENT_DMA_MMAP,
thus when CONFIG_MMU is gone from dma_common_mmap() their behaviour stays
unchanged.
ARM is not converted to ARCH_NO_COHERENT_DMA_MMAP because it 1)
already has mmap callback which can handle (at some extent) NOMMU 2)
already defines dummy pgprot_noncached() for NOMMU build.
c6x and frv stay untouched since they already have ARCH_NO_COHERENT_DMA_MMAP.
Cc: Steven Miao <realmz6@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
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Reduce the kernel size by only building dma_noop_ops for those
architectures that actually use it. This was suggested by
Christoph Hellwig.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>
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Some builds of m32r were failing as it tried to build few drivers which
needed dma but m32r is not having dma support. Objections were raised
when it was tried to make those drivers depend on HAS_DMA. So the next
best thing is to add dma support to m32r. dma_noop is a very simple dma
with 1:1 memory mapping.
Link: http://lkml.kernel.org/r/1475949198-31623-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The binary GCD algorithm is based on the following facts:
1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2)
2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b)
3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b)
Even on x86 machines with reasonable division hardware, the binary
algorithm runs about 25% faster (80% the execution time) than the
division-based Euclidian algorithm.
On platforms like Alpha and ARMv6 where division is a function call to
emulation code, it's even more significant.
There are two variants of the code here, depending on whether a fast
__ffs (find least significant set bit) instruction is available. This
allows the unpredictable branches in the bit-at-a-time shifting loop to
be eliminated.
If fast __ffs is not available, the "even/odd" GCD variant is used.
I use the following code to benchmark:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#define swap(a, b) \
do { \
a ^= b; \
b ^= a; \
a ^= b; \
} while (0)
unsigned long gcd0(unsigned long a, unsigned long b)
{
unsigned long r;
if (a < b) {
swap(a, b);
}
if (b == 0)
return a;
while ((r = a % b) != 0) {
a = b;
b = r;
}
return b;
}
unsigned long gcd1(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
b >>= __builtin_ctzl(b);
for (;;) {
a >>= __builtin_ctzl(a);
if (a == b)
return a << __builtin_ctzl(r);
if (a < b)
swap(a, b);
a -= b;
}
}
unsigned long gcd2(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
r &= -r;
while (!(b & r))
b >>= 1;
for (;;) {
while (!(a & r))
a >>= 1;
if (a == b)
return a;
if (a < b)
swap(a, b);
a -= b;
a >>= 1;
if (a & r)
a += b;
a >>= 1;
}
}
unsigned long gcd3(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
b >>= __builtin_ctzl(b);
if (b == 1)
return r & -r;
for (;;) {
a >>= __builtin_ctzl(a);
if (a == 1)
return r & -r;
if (a == b)
return a << __builtin_ctzl(r);
if (a < b)
swap(a, b);
a -= b;
}
}
unsigned long gcd4(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
r &= -r;
while (!(b & r))
b >>= 1;
if (b == r)
return r;
for (;;) {
while (!(a & r))
a >>= 1;
if (a == r)
return r;
if (a == b)
return a;
if (a < b)
swap(a, b);
a -= b;
a >>= 1;
if (a & r)
a += b;
a >>= 1;
}
}
static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = {
gcd0, gcd1, gcd2, gcd3, gcd4,
};
#define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0]))
#if defined(__x86_64__)
#define rdtscll(val) do { \
unsigned long __a,__d; \
__asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
(val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \
} while(0)
static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
unsigned long a, unsigned long b, unsigned long *res)
{
unsigned long long start, end;
unsigned long long ret;
unsigned long gcd_res;
rdtscll(start);
gcd_res = gcd(a, b);
rdtscll(end);
if (end >= start)
ret = end - start;
else
ret = ~0ULL - start + 1 + end;
*res = gcd_res;
return ret;
}
#else
static inline struct timespec read_time(void)
{
struct timespec time;
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time);
return time;
}
static inline unsigned long long diff_time(struct timespec start, struct timespec end)
{
struct timespec temp;
if ((end.tv_nsec - start.tv_nsec) < 0) {
temp.tv_sec = end.tv_sec - start.tv_sec - 1;
temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec;
} else {
temp.tv_sec = end.tv_sec - start.tv_sec;
temp.tv_nsec = end.tv_nsec - start.tv_nsec;
}
return temp.tv_sec * 1000000000ULL + temp.tv_nsec;
}
static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
unsigned long a, unsigned long b, unsigned long *res)
{
struct timespec start, end;
unsigned long gcd_res;
start = read_time();
gcd_res = gcd(a, b);
end = read_time();
*res = gcd_res;
return diff_time(start, end);
}
#endif
static inline unsigned long get_rand()
{
if (sizeof(long) == 8)
return (unsigned long)rand() << 32 | rand();
else
return rand();
}
int main(int argc, char **argv)
{
unsigned int seed = time(0);
int loops = 100;
int repeats = 1000;
unsigned long (*res)[TEST_ENTRIES];
unsigned long long elapsed[TEST_ENTRIES];
int i, j, k;
for (;;) {
int opt = getopt(argc, argv, "n:r:s:");
/* End condition always first */
if (opt == -1)
break;
switch (opt) {
case 'n':
loops = atoi(optarg);
break;
case 'r':
repeats = atoi(optarg);
break;
case 's':
seed = strtoul(optarg, NULL, 10);
break;
default:
/* You won't actually get here. */
break;
}
}
res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops);
memset(elapsed, 0, sizeof(elapsed));
srand(seed);
for (j = 0; j < loops; j++) {
unsigned long a = get_rand();
/* Do we have args? */
unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
unsigned long long min_elapsed[TEST_ENTRIES];
for (k = 0; k < repeats; k++) {
for (i = 0; i < TEST_ENTRIES; i++) {
unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]);
if (k == 0 || min_elapsed[i] > tmp)
min_elapsed[i] = tmp;
}
}
for (i = 0; i < TEST_ENTRIES; i++)
elapsed[i] += min_elapsed[i];
}
for (i = 0; i < TEST_ENTRIES; i++)
printf("gcd%d: elapsed %llu\n", i, elapsed[i]);
k = 0;
srand(seed);
for (j = 0; j < loops; j++) {
unsigned long a = get_rand();
unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
for (i = 1; i < TEST_ENTRIES; i++) {
if (res[j][i] != res[j][0])
break;
}
if (i < TEST_ENTRIES) {
if (k == 0) {
k = 1;
fprintf(stderr, "Error:\n");
}
fprintf(stderr, "gcd(%lu, %lu): ", a, b);
for (i = 0; i < TEST_ENTRIES; i++)
fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n");
}
}
if (k == 0)
fprintf(stderr, "PASS\n");
free(res);
return 0;
}
Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got:
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 10174
gcd1: elapsed 2120
gcd2: elapsed 2902
gcd3: elapsed 2039
gcd4: elapsed 2812
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9309
gcd1: elapsed 2280
gcd2: elapsed 2822
gcd3: elapsed 2217
gcd4: elapsed 2710
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9589
gcd1: elapsed 2098
gcd2: elapsed 2815
gcd3: elapsed 2030
gcd4: elapsed 2718
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9914
gcd1: elapsed 2309
gcd2: elapsed 2779
gcd3: elapsed 2228
gcd4: elapsed 2709
PASS
[akpm@linux-foundation.org: avoid #defining a CONFIG_ variable]
Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"PCI changes for v4.6:
Enumeration:
- Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
- Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas
Resource management:
- Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
- Don't assign or reassign immutable resources (Bjorn Helgaas)
- Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
- Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
- Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
- ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
- ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
- MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
- Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
- Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
- rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
- designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
Virtualization:
- Wait for up to 1000ms after FLR reset (Alex Williamson)
- Support SR-IOV on any function type (Kelly Zytaruk)
- Add ACS quirk for all Cavium devices (Manish Jaggi)
AER:
- Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
- Restore pci_ops pointer while calling original pci_ops (David Daney)
- Fix aer_inject error codes (Jean Delvare)
- Use dev_warn() in aer_inject (Jean Delvare)
- Log actual error causes in aer_inject (Jean Delvare)
- Log aer_inject error injections (Jean Delvare)
VPD:
- Prevent VPD access for buggy devices (Babu Moger)
- Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
- Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
- Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
- Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
- Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
- Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
- Update VPD definitions (Hannes Reinecke)
- Allow access to VPD attributes with size 0 (Hannes Reinecke)
- Determine actual VPD size on first access (Hannes Reinecke)
Generic host bridge driver:
- Move structure definitions to separate header file (David Daney)
- Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
- Expose pci_host_common_probe() for use by other drivers (David Daney)
Altera host bridge driver:
- Fix altera_pcie_link_is_up() (Ley Foon Tan)
Cavium ThunderX host bridge driver:
- Add PCIe host driver for ThunderX processors (David Daney)
- Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)
Freescale i.MX6 host bridge driver:
- Add DT bindings to configure PHY Tx driver settings (Justin Waters)
- Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
- Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
- Remove broken Gen2 workaround (Lucas Stach)
- Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)
Freescale Layerscape host bridge driver:
- Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)
Intel VMD host bridge driver:
- Attach VMD resources to parent domain's resource tree (Jon Derrick)
- Set bus resource start to 0 (Keith Busch)
Microsoft Hyper-V host bridge driver:
- Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
- Look up IRQ domain by fwnode_handle (Jake Oshins)
- Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)
NVIDIA Tegra host bridge driver:
- Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
- Implement ->{add,remove}_bus() callbacks (Thierry Reding)
- Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
- Track bus -> CPU mapping (Thierry Reding)
- Remove misleading PHYS_OFFSET (Thierry Reding)
Renesas R-Car host bridge driver:
- Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)
Synopsys DesignWare host bridge driver:
- ARC: Add PCI support (Joao Pinto)
- Add generic dw_pcie_wait_for_link() (Joao Pinto)
- Add default link up check if sub-driver doesn't override (Joao Pinto)
- Add driver for prototyping kits based on ARC SDP (Joao Pinto)
TI Keystone host bridge driver:
- Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)
Xilinx AXI host bridge driver:
- Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
- Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
- Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
- Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
- microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)
Xilinx NWL host bridge driver:
- Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)
Miscellaneous:
- Check device_attach() return value always (Bjorn Helgaas)
- Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
- Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
- ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
- Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
- Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
- Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
- unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
- Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
- Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
- Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
- frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
- Move pci_dma_* helpers to common code (Christoph Hellwig)
- Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
- Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
- Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)"
* tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits)
PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition
PCI: designware: Add driver for prototyping kits based on ARC SDP
PCI: designware: Add default link up check if sub-driver doesn't override
PCI: designware: Add generic dw_pcie_wait_for_link()
PCI: Cleanup pci/pcie/Kconfig whitespace
PCI: Simplify pci_create_attr() control flow
PCI: Don't leak memory if sysfs_create_bin_file() fails
PCI: Simplify sysfs ROM cleanup
PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY
MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource
MIPS: Loongson 3: Use temporary struct resource * to avoid repetition
ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource
ia64/PCI: Use ioremap() instead of open-coded equivalent
ia64/PCI: Use temporary struct resource * to avoid repetition
PCI: Clean up pci_map_rom() whitespace
PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs
PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices
PCI: thunder: Add PCIe host driver for ThunderX processors
PCI: generic: Expose pci_host_common_probe() for use by other drivers
PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe()
...
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Include pci/hotplug/Kconfig directly from pci/Kconfig, so arches don't
have to source both pci/Kconfig and pci/hotplug/Kconfig.
Note that this effectively adds pci/hotplug/Kconfig to the following
arches, because they already sourced drivers/pci/Kconfig but they
previously did not source drivers/pci/hotplug/Kconfig:
alpha
arm
avr32
frv
m68k
microblaze
mn10300
sparc
unicore32
Inspired-by-patch-from: Bogicevic Sasa <brutallesale@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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One of the randconfig build failed with the error:
arch/m32r/kernel/smp.c: In function 'smp_flush_tlb_mm':
arch/m32r/kernel/smp.c:283:20: error: subscripted value is neither array nor pointer nor vector
mmc = &mm->context[cpu_id];
^
arch/m32r/kernel/smp.c: In function 'smp_flush_tlb_page':
arch/m32r/kernel/smp.c:353:20: error: subscripted value is neither array nor pointer nor vector
mmc = &mm->context[cpu_id];
^
arch/m32r/kernel/smp.c: In function 'smp_invalidate_interrupt':
arch/m32r/kernel/smp.c:479:41: error: subscripted value is neither array nor pointer nor vector
unsigned long *mmc = &flush_mm->context[cpu_id];
It turned out that CONFIG_SMP was defined but CONFIG_MMU was not
defined. But arch/m32r/include/asm/mmu.h only defines mm_context_t as
an array when both CONFIG_SMP and CONFIG_MMU are defined. And
arch/m32r/kernel/smp.c is always using context as an array. So without
MMU SMP can not work.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Let all the archs that implement devmem_is_allowed() opt-in to a common
definition of CONFIG_STRICT_DEVM in lib/Kconfig.debug.
Cc: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
[heiko: drop 'default y' for s390]
Acked-by: Ingo Molnar <mingo@redhat.com>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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If the renamed symbol is defined lib/iomap.c implements ioport_map and
ioport_unmap and currently (nearly) all platforms define the port
accessor functions outb/inb and friend unconditionally. So
HAS_IOPORT_MAP is the better name for this.
Consequently NO_IOPORT is renamed to NO_IOPORT_MAP.
The motivation for this change is to reintroduce a symbol HAS_IOPORT
that signals if outb/int et al are available. I will address that at
least one merge window later though to keep surprises to a minimum and
catch new introductions of (HAS|NO)_IOPORT.
The changes in this commit were done using:
$ git grep -l -E '(NO|HAS)_IOPORT' | xargs perl -p -i -e 's/\b((?:CONFIG_)?(?:NO|HAS)_IOPORT)\b/$1_MAP/'
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Remove an outdated reference to "most personal computers" having only one
CPU, and change the use of "singleprocessor" and "single processor" in
CONFIG_SMP's documentation to "uniprocessor" across all arches where that
documentation is present.
Signed-off-by: Robert Graffham <psquid@psquid.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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We've switched over every architecture that supports SMP to it, so
remove the new useless config variable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Original posting:
http://lkml.kernel.org/r/20121214184202.F54094D9@kernel.stglabs.ibm.com
Several architectures have similar stack debugging config options.
They all pretty much do the same thing, some with slightly
differing help text.
This patch changes the architectures to instead enable a Kconfig
boolean, and then use that boolean in the generic Kconfig.debug
to present the actual menu option. This removes a bunch of
duplication and adds consistency across arches.
Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com> [for tile]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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In commit 887cbce0adea ("arch Kconfig: centralise ARCH_NO_VIRT_TO_BUS")
I introduced the config sybmol HAVE_VIRT_TO_BUS and selected that where
needed. I am not sure what I was thinking. Instead, just directly
select VIRT_TO_BUS where it is needed.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Change it to CONFIG_HAVE_VIRT_TO_BUS and set it in all architecures
that already provide virt_to_bus().
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: H Hartley Sweeten <hartleys@visionengravers.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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All architectures have
CONFIG_GENERIC_KERNEL_THREAD
CONFIG_GENERIC_KERNEL_EXECVE
__ARCH_WANT_SYS_EXECVE
None of them have __ARCH_WANT_KERNEL_EXECVE and there are only two callers
of kernel_execve() (which is a trivial wrapper for do_execve() now) left.
Kill the conditionals and make both callers use do_execve().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module signing support from Rusty Russell:
"module signing is the highlight, but it's an all-over David Howells frenzy..."
Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG.
* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits)
X.509: Fix indefinite length element skip error handling
X.509: Convert some printk calls to pr_devel
asymmetric keys: fix printk format warning
MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking
MODSIGN: Make mrproper should remove generated files.
MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs
MODSIGN: Use the same digest for the autogen key sig as for the module sig
MODSIGN: Sign modules during the build process
MODSIGN: Provide a script for generating a key ID from an X.509 cert
MODSIGN: Implement module signature checking
MODSIGN: Provide module signing public keys to the kernel
MODSIGN: Automatically generate module signing keys if missing
MODSIGN: Provide Kconfig options
MODSIGN: Provide gitignore and make clean rules for extra files
MODSIGN: Add FIPS policy
module: signature checking hook
X.509: Add a crypto key parser for binary (DER) X.509 certificates
MPILIB: Provide a function to read raw data into an MPI
X.509: Add an ASN.1 decoder
X.509: Add simple ASN.1 grammar compiler
...
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Introduce HAVE_DEBUG_BUGVERBOSE config option and select it in
corresponding architecture Kconfig files. Architectures that already
select GENERIC_BUG don't need to select HAVE_DEBUG_BUGVERBOSE.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Use the mapping of Elf_[SPE]hdr, Elf_Addr, Elf_Sym, Elf_Dyn, Elf_Rel/Rela,
ELF_R_TYPE() and ELF_R_SYM() to either the 32-bit version or the 64-bit version
into asm-generic/module.h for all arches bar MIPS.
Also, use the generic definition mod_arch_specific where possible.
To this end, I've defined three new config bools:
(*) HAVE_MOD_ARCH_SPECIFIC
Arches define this if they don't want to use the empty generic
mod_arch_specific struct.
(*) MODULES_USE_ELF_RELA
Arches define this if their modules can contain RELA records. This causes
the Elf_Rela mapping to be emitted and allows apply_relocate_add() to be
defined by the arch rather than have the core emit an error message.
(*) MODULES_USE_ELF_REL
Arches define this if their modules can contain REL records. This causes
the Elf_Rel mapping to be emitted and allows apply_relocate() to be
defined by the arch rather than have the core emit an error message.
Note that it is possible to allow both REL and RELA records: m68k and mips are
two arches that do this.
With this, some arch asm/module.h files can be deleted entirely and replaced
with a generic-y marker in the arch Kbuild file.
Additionally, I have removed the bits from m32r and score that handle the
unsupported type of relocation record as that's now handled centrally.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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Rather than #define the options manually in the architecture code, add
Kconfig options for them and select them there instead. This also allows
us to select the compat IPC version parsing automatically for platforms
using the old compat IPC interface.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Anna-Maria Gleixner <anna-maria@glx-um.de>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Link: http://lkml.kernel.org/r/20120518163105.678581749@glx-um.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scsi: drop unused Kconfig symbol
pci: drop unused Kconfig symbol
stmmac: drop unused Kconfig symbol
x86: drop unused Kconfig symbol
powerpc: drop unused Kconfig symbols
powerpc: 40x: drop unused Kconfig symbol
mips: drop unused Kconfig symbols
openrisc: drop unused Kconfig symbols
arm: at91: drop unused Kconfig symbol
samples: drop unused Kconfig symbol
m32r: drop unused Kconfig symbol
score: drop unused Kconfig symbols
sh: drop unused Kconfig symbol
um: drop unused Kconfig symbol
sparc: drop unused Kconfig symbol
alpha: drop unused Kconfig symbol
Fix up trivial conflict in drivers/net/ethernet/stmicro/stmmac/Kconfig
as per Michal: the STMMAC_DUAL_MAC config variable is still unused and
should be deleted.
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Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michal Marek <mmarek@suse.cz>
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Atomic64 is now a valid type in Linux. Archs that do not have their own
version of atomic64 operators are to use the generic operations.
The m32r architecture needs to define GENERIC_ATOMIC64.
Link: http://lkml.kernel.org/r/20111013085936.GA13046@elte.hu
Link: http://lkml.kernel.org/r/1318516816.12224.12.camel@gandalf.stny.rr.com
Link: http://lkml.kernel.org/r/20111017185440.GB5545@elte.hu
Acked-by: Hirokazu Takata <takata@linux-m32r.org>
Acked-by: David Rientjes <rientjes@google.com>
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Use the generic preempt config definition in m32r instead of
using a custom one.
This also makes it handle the new CONFIG_PREEMPT_COUNT that
need to be selected by CONFIG_PREEMPT.
Without that it breaks
kernel/sched.c: In function 'preempt_schedule':
kernel/sched.c:4364: error: implicit declaration of function 'add_preempt_count_notrace'
kernel/sched.c:4366: error: implicit declaration of function 'sub_preempt_count_notrace'
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
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By the previous style change, CONFIG_GENERIC_FIND_NEXT_BIT,
CONFIG_GENERIC_FIND_BIT_LE, and CONFIG_GENERIC_FIND_LAST_BIT are not used
to test for existence of find bitops anymore.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (23 commits)
genirq: Expand generic show_interrupts()
gpio: Fold irq_set_chip/irq_set_handler to irq_set_chip_and_handler
gpio: Cleanup genirq namespace
arm: ep93xx: Add basic interrupt info
arm/gpio: Remove three copies of broken and racy debug code
xtensa: Use generic show_interrupts()
xtensa: Convert genirq namespace
xtensa: Use generic IRQ Kconfig and set GENERIC_HARDIRQS_NO_DEPRECATED
xtensa: Convert s6000 gpio irq_chip to new functions
xtensa: Convert main irq_chip to new functions
um: Use generic show_interrupts()
um: Convert genirq namespace
m32r: Use generic show_interrupts()
m32r: Convert genirq namespace
h8300: Use generic show_interrupts()
h8300: Convert genirq namespace
avr32: Cleanup eic_set_irq_type()
avr32: Use generic show_interrupts()
avr: Cleanup genirq namespace
avr32: Use generic IRQ config, enable GENERIC_HARDIRQS_NO_DEPRECATED
...
Fix up trivial conflict in drivers/gpio/timbgpio.c
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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This introduces CONFIG_GENERIC_FIND_BIT_LE to tell whether to use generic
implementation of find_*_bit_le() in lib/find_next_bit.c or not.
For now we select CONFIG_GENERIC_FIND_BIT_LE for all architectures which
enable CONFIG_GENERIC_FIND_NEXT_BIT.
But m68knommu wants to define own faster find_next_zero_bit_le() and
continues using generic find_next_{,zero_}bit().
(CONFIG_GENERIC_FIND_NEXT_BIT and !CONFIG_GENERIC_FIND_BIT_LE)
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Use the generic irq Kconfig. Select GENERIC_HARDIRQS_NO_DEPRECATED as
we have converted all irq_chip functions.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Paul Mundt <lethal@linux-sh.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (38 commits)
kbuild: convert `arch/tile' to the kconfig mainmenu upgrade
README: cite nconfig
Revert "kconfig: Temporarily disable dependency warnings"
kconfig: Use PATH_MAX instead of 128 for path buffer sizes.
kconfig: Fix realloc usage()
kconfig: Propagate const
kconfig: Don't go out from read config loop when you read new symbol
kconfig: fix menuconfig on debian lenny
kbuild: migrate all arch to the kconfig mainmenu upgrade
kconfig: expand file names
kconfig: use the file's name of sourced file
kconfig: constify file name
kconfig: don't emit warning upon rootmenu's prompt redefinition
kconfig: replace KERNELVERSION usage by the mainmenu's prompt
kconfig: delay gconf window initialization
kconfig: expand by default the rootmenu's prompt
kconfig: add a symbol string expansion helper
kconfig: regen parser
kconfig: implement the `mainmenu' directive
kconfig: allow PACKAGE to be defined on the compiler's command-line
...
Fix up trivial conflict in arch/mn10300/Kconfig
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The patch below updates broken web addresses in the arch directory.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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We need to revert the temporary hack in 71ebc01, hence the merge.
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Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Michal Marek <mmarek@suse.cz>
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Now that all arches have been converted over to use generic time via
clocksources or arch_gettimeoffset(), we can remove the GENERIC_TIME
config option and simplify the generic code.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <1279068988-21864-4-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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- Support bzip2 and lzma kernel compression for m32r.
- Clean up arch/m32r/boot/compressed/misc.c.
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
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Convert m32r to use GENERIC_TIME via the arch_getoffset() infrastructure,
reducing the amount of arch specific code we need to maintain.
I also noted that m32r doesn't seem to be taking the xtime write lock
before calling do_timer()! That looks like a pretty bad bug to me. If
folks agree, let me know and I can move the lock grab to the correct spot.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Conflicts:
arch/x86/kernel/io_apic.c
kernel/sched.c
kernel/sched_stats.h
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Impact: cleanup
Each SMP arch defines these themselves. Move them to a central
location.
Twists:
1) Some archs (m32, parisc, s390) set possible_map to all 1, so we add a
CONFIG_INIT_ALL_POSSIBLE for this rather than break them.
2) mips and sparc32 '#define cpu_possible_map phys_cpu_present_map'.
Those archs simply have phys_cpu_present_map replaced everywhere.
3) Alpha defined cpu_possible_map to cpu_present_map; this is tricky
so I just manipulate them both in sync.
4) IA64, cris and m32r have gratuitous 'extern cpumask_t cpu_possible_map'
declarations.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Mike Travis <travis@sgi.com>
Cc: ink@jurassic.park.msu.ru
Cc: rmk@arm.linux.org.uk
Cc: starvik@axis.com
Cc: tony.luck@intel.com
Cc: takata@linux-m32r.org
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: paulus@samba.org
Cc: schwidefsky@de.ibm.com
Cc: lethal@linux-sh.org
Cc: wli@holomorphy.com
Cc: davem@davemloft.net
Cc: jdike@addtoit.com
Cc: mingo@redhat.com
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Impact: cleanup, change .config option name
We had this ugly config name for a long time for hysteric raisons.
Rename it to a saner name.
We still cannot get rid of it completely, until /proc/<pid>/stack
usage replaces WCHAN usage for good.
We'll be able to do that in the v2.6.29/v2.6.30 timeframe.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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This patch implements a new freezer subsystem in the control groups
framework. It provides a way to stop and resume execution of all tasks in
a cgroup by writing in the cgroup filesystem.
The freezer subsystem in the container filesystem defines a file named
freezer.state. Writing "FROZEN" to the state file will freeze all tasks
in the cgroup. Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup. Reading will return the current state.
* Examples of usage :
# mkdir /containers/freezer
# mount -t cgroup -ofreezer freezer /containers
# mkdir /containers/0
# echo $some_pid > /containers/0/tasks
to get status of the freezer subsystem :
# cat /containers/0/freezer.state
RUNNING
to freeze all tasks in the container :
# echo FROZEN > /containers/0/freezer.state
# cat /containers/0/freezer.state
FREEZING
# cat /containers/0/freezer.state
FROZEN
to unfreeze all tasks in the container :
# echo RUNNING > /containers/0/freezer.state
# cat /containers/0/freezer.state
RUNNING
This is the basic mechanism which should do the right thing for user space
task in a simple scenario.
It's important to note that freezing can be incomplete. In that case we
return EBUSY. This means that some tasks in the cgroup are busy doing
something that prevents us from completely freezing the cgroup at this
time. After EBUSY, the cgroup will remain partially frozen -- reflected
by freezer.state reporting "FREEZING" when read. The state will remain
"FREEZING" until one of these things happens:
1) Userspace cancels the freezing operation by writing "RUNNING" to
the freezer.state file
2) Userspace retries the freezing operation by writing "FROZEN" to
the freezer.state file (writing "FREEZING" is not legal
and returns EIO)
3) The tasks that blocked the cgroup from entering the "FROZEN"
state disappear from the cgroup's set of tasks.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: export thaw_process]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Tested-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
include/asm-x86/statfs.h
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As far as I know no M32R hardware actually has ISA slots.
And ISA drivers don't compile on M32R.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
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Remove the unused NOHIGHMEM option.
Reviewed-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
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We don't need this any more; arguably we never really did.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
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This converts m32r to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single(). Not tested,
not even compiled.
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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To allow flexible configuration of IDE introduce HAVE_IDE.
All archs except arm, um and s390 unconditionally select it.
For arm the actual configuration determine if IDE is supported.
This is a step towards introducing drivers/Kconfig for arm.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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When the conversion factor between jiffies and milli- or microseconds is
not a single multiply or divide, as for the case of HZ == 300, we currently
do a multiply followed by a divide. The intervening result, however, is
subject to overflows, especially since the fraction is not simplified (for
HZ == 300, we multiply by 300 and divide by 1000).
This is exposed to the user when passing a large timeout to poll(), for
example.
This patch replaces the multiply-divide with a reciprocal multiplication on
32-bit platforms. When the input is an unsigned long, there is no portable
way to do this on 64-bit platforms there is no portable way to do this
since it requires a 128-bit intermediate result (which gcc does support on
64-bit platforms but may generate libgcc calls, e.g. on 64-bit s390), but
since the output is a 32-bit integer in the cases affected, just simplify
the multiply-divide (*3/10 instead of *300/1000).
The reciprocal multiply used can have off-by-one errors in the upper half
of the valid output range. This could be avoided at the expense of having
to deal with a potential 65-bit intermediate result. Since the intent is
to avoid overflow problems and most of the other time conversions are only
semiexact, the off-by-one errors were considered an acceptable tradeoff.
At Ralf Baechle's suggestion, this version uses a Perl script to compute
the necessary constants. We already have dependencies on Perl for kernel
compiles. This does, however, require the Perl module Math::BigInt, which
is included in the standard Perl distribution starting with version 5.8.0.
In order to support older versions of Perl, include a table of canned
constants in the script itself, and structure the script so that
Math::BigInt isn't required if pulling values from said table.
Running the script requires that the HZ value is available from the
Makefile. Thus, this patch also adds the Kconfig variable CONFIG_HZ to the
architectures which didn't already have it (alpha, cris, frv, h8300, m32r,
m68k, m68knommu, sparc, v850, and xtensa.) It does *not* touch the sh or
sh64 architectures, since Paul Mundt has dealt with those separately in the
sh tree.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Ralf Baechle <ralf@linux-mips.org>,
Cc: Sam Ravnborg <sam@ravnborg.org>,
Cc: Paul Mundt <lethal@linux-sh.org>,
Cc: Richard Henderson <rth@twiddle.net>,
Cc: Michael Starvik <starvik@axis.com>,
Cc: David Howells <dhowells@redhat.com>,
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>,
Cc: Hirokazu Takata <takata@linux-m32r.org>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>,
Cc: Roman Zippel <zippel@linux-m68k.org>,
Cc: William L. Irwin <sparclinux@vger.kernel.org>,
Cc: Chris Zankel <chris@zankel.net>,
Cc: H. Peter Anvin <hpa@zytor.com>,
Cc: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|