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2012-03-27Merge branch 'for-linus-3.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML changes from Richard Weinberger: "Mostly bug fixes and cleanups" * 'for-linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (35 commits) um: Update defconfig um: Switch to large mcmodel on x86_64 MTD: Relax dependencies um: Wire CONFIG_GENERIC_IO up um: Serve io_remap_pfn_range() Introduce CONFIG_GENERIC_IO um: allow SUBARCH=x86 um: most of the SUBARCH uses can be killed um: deadlock in line_write_interrupt() um: don't bother trying to rebuild CHECKFLAGS for USER_OBJS um: use the right ifdef around exports in user_syms.c um: a bunch of headers can be killed by using generic-y um: ptrace-generic.h doesn't need user.h um: kill HOST_TASK_PID um: remove pointless include of asm/fixmap.h from asm/pgtable.h um: asm-offsets.h might as well come from underlying arch... um: merge processor_{32,64}.h a bit... um: switch close_chan() to struct line um: race fix: initialize delayed_work *before* registering IRQ um: line->have_irq is never checked... ...
2012-03-25um: Update defconfigRichard Weinberger
Enable ext4, cgroups and devtmpfs. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: Switch to large mcmodel on x86_64Richard Weinberger
x86_64 UML is unable to load modules if more than 504MiB of memory are used. This happens because on x86_64 the UML process has a quite high start address (typically around 0x6000000). If UML's memory is larger than 504MiB VMALLOC_START happens to be after 0x8000000. This is no problem unless one loads a module which was built with R_X86_64_32S relocations. Symbols with a location > 0x8000000 cannot be used with R_X86_64_32S To deal with this x86_64 UML has to be compiled with -mcmodel=large such that no R_X86_64_32S relocations are used. Signed-off-by: Richard Weinberger <richard@nod.at> Reported-by: 전하늘 <allskyee@gmail.com>
2012-03-25um: Wire CONFIG_GENERIC_IO upRichard Weinberger
UML has no io memory but implements everything defined in generic-asm/io.h. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: Serve io_remap_pfn_range()Richard Weinberger
At some places io_remap_pfn_range() is needed. UML has to serve it like all other archs do. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: most of the SUBARCH uses can be killedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [richard@nod.at: Re-export SUBARCH in arch/um/Makefile] Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: deadlock in line_write_interrupt()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: don't bother trying to rebuild CHECKFLAGS for USER_OBJSAl Viro
... just strip NOSTDINC_FLAGS out of it for those Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: use the right ifdef around exports in user_syms.cAl Viro
... the same one that controls whether elf_aux.o is included into the build, bringing the vsyscall_e... into it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: a bunch of headers can be killed by using generic-yAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: ptrace-generic.h doesn't need user.hAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: kill HOST_TASK_PIDAl Viro
just provide get_current_pid() to the userland side of things instead of get_current() + manual poking in its results Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: remove pointless include of asm/fixmap.h from asm/pgtable.hAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: asm-offsets.h might as well come from underlying arch...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: switch close_chan() to struct lineAl Viro
... and switch chan_interrupt() to directly calling close_one_chan(), so we can lose delay_free_irq argument of close_chan() as well. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: race fix: initialize delayed_work *before* registering IRQAl Viro
... since chan_interrupt() might schedule it if there's too much incoming data. Kill task argument of chan_interrupt(), while we are at it - it's always &line->task. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: line->have_irq is never checked...Al Viro
looks like a half-arsed duplicate of line->enabled Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: chan_init_pri is dead nowAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: switch users of ->chan_list to ->chan_{in,out} (easy cases)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: sorting out the chan mess, part 1Al Viro
put references to in and out chans associated with line into explicit struct chan * fields in it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: finally kill ->init_str leaksAl Viro
now we can do that... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: get rid of lines_init()Al Viro
move config-independent parts of initialization into register_lines(), call setup_one_line() after it instead of abusing ->init_str. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: switch line.c tty drivers to dynamic device creationAl Viro
Current code doesn't update the symlinks in /sys/dev/char when we add/remove tty lines. Fixing that allows to stop messing with ->valid before the driver registration, which is a Good Thing(tm) - we shouldn't have it set before we really have the things set up and ready for line_open(). We need tty_driver available to call tty_{un,}register_device(), so we just stash a reference to it into struct line_driver. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: fix races between line_open() and line_config()Al Viro
Pull parse_chan_pair() call into setup_one_line(), under the mutex. We really don't want open() to succeed before parse_chan_pair() had been done (or after it has failed, BTW). We also want "remove con<n>" to free irqs, etc., same as "config con<n>=none". Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: convert count_lock to mutex, fix a race in line_open()Al Viro
If two processes are opening the same line, the second to get into line_open() will decide that it doesn't need to do anything (correctly) or wait for anything. The latter, unfortunately, is incorrect - the first opener might not be through yet. We need to have exclusion covering the entire line_init(), including the blocking parts. Moreover, the next patch will need to widen the exclusion on mconsole side of things, also including the blocking bits, so let's just convert that sucker to mutex... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: get rid of the init_prio messAl Viro
make line_setup() act on a separate array of conf strings + default conf, have lines array initialized explicitly by that data, bury LINE_INIT() macro from hell. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: switch line_config() to setup_one_line()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: switch line_remove() to setup_one_line()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: auxvec.h is never usedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: clean up the includes in ubdAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-25um: irq: Remove IRQF_DISABLEDYong Zhang
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled], We run all interrupt handlers with interrupts disabled and we even check and yell when an interrupt handler returns with interrupts enabled (see commit [b738a50a: genirq: Warn when handler enables interrupts]). So now this flag is a NOOP and can be removed. Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-23um: use set_current_blocked() and block_sigmask()Matt Fleming
As described in commit e6fa16ab9c1e ("signal: sigprocmask() should do retarget_shared_pending()") the modification of current->blocked is incorrect as we need to check whether the signal we're about to block is pending in the shared queue. Also, use the new helper function introduced in commit 5e6292c0f28f ("signal: add block_sigmask() for adding sigmask to current->blocked") which centralises the code for updating current->blocked after successfully delivering a signal and reduces the amount of duplicate code across architectures. In the past some architectures got this code wrong, so using this helper function should stop that from happening again. Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23um: don't restore current->blocked on errorMatt Fleming
If we fail to setup the signal stack frame then we don't need to restore current->blocked because it is not modified by setup_signal_stack_*. Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Richard Weinberger <richard@nod.at> Tested-by: Richard Weinberger <richard@nod.at> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "This is _not_ all; in particular, Miklos' and Jan's stuff is not there yet." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits) ext4: initialization of ext4_li_mtx needs to be done earlier debugfs-related mode_t whack-a-mole hfsplus: add an ioctl to bless files hfsplus: change finder_info to u32 hfsplus: initialise userflags qnx4: new helper - try_extent() qnx4: get rid of qnx4_bread/qnx4_getblk take removal of PF_FORKNOEXEC to flush_old_exec() trim includes in inode.c um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it um: embed ->stub_pages[] into mmu_context gadgetfs: list_for_each_safe() misuse ocfs2: fix leaks on failure exits in module_init ecryptfs: make register_filesystem() the last potential failure exit ntfs: forgets to unregister sysctls on register_filesystem() failure logfs: missing cleanup on register_filesystem() failure jfs: mising cleanup on register_filesystem() failure make configfs_pin_fs() return root dentry on success configfs: configfs_create_dir() has parent dentry in dentry->d_parent configfs: sanitize configfs_create() ...
2012-03-21Merge branch 'kmap_atomic' of git://github.com/congwang/linuxLinus Torvalds
Pull kmap_atomic cleanup from Cong Wang. It's been in -next for a long time, and it gets rid of the (no longer used) second argument to k[un]map_atomic(). Fix up a few trivial conflicts in various drivers, and do an "evil merge" to catch some new uses that have come in since Cong's tree. * 'kmap_atomic' of git://github.com/congwang/linux: (59 commits) feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename] drbd: remove the second argument of k[un]map_atomic() zcache: remove the second argument of k[un]map_atomic() gma500: remove the second argument of k[un]map_atomic() dm: remove the second argument of k[un]map_atomic() tomoyo: remove the second argument of k[un]map_atomic() sunrpc: remove the second argument of k[un]map_atomic() rds: remove the second argument of k[un]map_atomic() net: remove the second argument of k[un]map_atomic() mm: remove the second argument of k[un]map_atomic() lib: remove the second argument of k[un]map_atomic() power: remove the second argument of k[un]map_atomic() kdb: remove the second argument of k[un]map_atomic() udf: remove the second argument of k[un]map_atomic() ubifs: remove the second argument of k[un]map_atomic() squashfs: remove the second argument of k[un]map_atomic() reiserfs: remove the second argument of k[un]map_atomic() ocfs2: remove the second argument of k[un]map_atomic() ntfs: remove the second argument of k[un]map_atomic() ...
2012-03-20um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() ↵Al Viro
doesn't hold it ... while calling uml_dup_mmap() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20um: embed ->stub_pages[] into mmu_contextAl Viro
seriously, kmalloc() for two-element array of pointers? Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20um: remove the second argument of k[un]map_atomic()Cong Wang
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-02-17UML net: set addr_assign_type if random_ether_addr() usedDanny Kukawka
Set addr_assign_type correctly to NET_ADDR_RANDOM in case a random MAC address was generated and assigned to the netdevice. Return state from setup_etheraddr() about returning a random MAC address or not and check this state in eth_configure(). Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits) audit: no leading space in audit_log_d_path prefix audit: treat s_id as an untrusted string audit: fix signedness bug in audit_log_execve_info() audit: comparison on interprocess fields audit: implement all object interfield comparisons audit: allow interfield comparison between gid and ogid audit: complex interfield comparison helper audit: allow interfield comparison in audit rules Kernel: Audit Support For The ARM Platform audit: do not call audit_getname on error audit: only allow tasks to set their loginuid if it is -1 audit: remove task argument to audit_set_loginuid audit: allow audit matching on inode gid audit: allow matching on obj_uid audit: remove audit_finish_fork as it can't be called audit: reject entry,always rules audit: inline audit_free to simplify the look of generic code audit: drop audit_set_macxattr as it doesn't do anything audit: inline checks for not needing to collect aux records audit: drop some potentially inadvisable likely notations ... Use evil merge to fix up grammar mistakes in Kconfig file. Bad speling and horrible grammar (and copious swearing) is to be expected, but let's keep it to commit messages and comments, rather than expose it to users in config help texts or printouts.
2012-01-17audit: inline audit_syscall_entry to reduce burden on archsEric Paris
Every arch calls: if (unlikely(current->audit_context)) audit_syscall_entry() which requires knowledge about audit (the existance of audit_context) in the arch code. Just do it all in static inline in audit.h so that arch's can remain blissfully ignorant. Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17Audit: push audit success and retcode into arch ptrace.hEric Paris
The audit system previously expected arches calling to audit_syscall_exit to supply as arguments if the syscall was a success and what the return code was. Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things by converting from negative retcodes to an audit internal magic value stating success or failure. This helper was wrong and could indicate that a valid pointer returned to userspace was a failed syscall. The fix is to fix the layering foolishness. We now pass audit_syscall_exit a struct pt_reg and it in turns calls back into arch code to collect the return value and to determine if the syscall was a success or failure. We also define a generic is_syscall_success() macro which determines success/failure based on if the value is < -MAX_ERRNO. This works for arches like x86 which do not use a separate mechanism to indicate syscall failure. We make both the is_syscall_success() and regs_return_value() static inlines instead of macros. The reason is because the audit function must take a void* for the regs. (uml calls theirs struct uml_pt_regs instead of just struct pt_regs so audit_syscall_exit can't take a struct pt_regs). Since the audit function takes a void* we need to use static inlines to cast it back to the arch correct structure to dereference it. The other major change is that on some arches, like ia64, MIPS and ppc, we change regs_return_value() to give us the negative value on syscall failure. THE only other user of this macro, kretprobe_example.c, won't notice and it makes the value signed consistently for the audit functions across all archs. In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old audit code as the return value. But the ptrace_64.h code defined the macro regs_return_value() as regs[3]. I have no idea which one is correct, but this patch now uses the regs_return_value() function, so it now uses regs[3]. For powerpc we previously used regs->result but now use the regs_return_value() function which uses regs->gprs[3]. regs->gprs[3] is always positive so the regs_return_value(), much like ia64 makes it negative before calling the audit code when appropriate. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion] Acked-by: Tony Luck <tony.luck@intel.com> [for ia64] Acked-by: Richard Weinberger <richard@nod.at> [for uml] Acked-by: David S. Miller <davem@davemloft.net> [for sparc] Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips] Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
2012-01-16Merge branch 'x86-syscall-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move <asm/asm-offsets.h> from trace_syscalls.c to asm/syscall.h x86, um: Fix typo in 32-bit system call modifications um: Use $(srctree) not $(KBUILD_SRC) x86, um: Mark system call tables readonly x86, um: Use the same style generated syscall tables as native um: Generate headers before generating user-offsets.s um: Run host archheaders, allow use of host generated headers kbuild, headers.sh: Don't make archheaders explicitly x86, syscall: Allow syscall offset to be symbolic x86, syscall: Re-fix typo in comment x86: Simplify syscallhdr.sh x86: Generate system call tables and unistd_*.h from tables checksyscalls: Use arch/x86/syscalls/syscall_32.tbl as source x86: Machine-readable syscall tables and scripts to process them trace: Include <asm/asm-offsets.h> in trace_syscalls.c x86-64, ia32: Move compat_ni_syscall into C and its own file x86-64, syscall: Adjust comment spacing and remove typo kbuild: Add support for an "archheaders" target kbuild: Add support for installing generated asm headers
2012-01-11cpu: Register a generic CPU device on architectures that currently do notBen Hutchings
frv, h8300, m68k, microblaze, openrisc, score, um and xtensa currently do not register a CPU device. Add the config option GENERIC_CPU_DEVICES which causes a generic CPU device to be registered for each present CPU, and make all these architectures select it. Richard Weinberger <richard@nod.at> covered UML and suggested using per_cpu. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-08Merge branch 'pm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm * 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits) PM / Hibernate: Implement compat_ioctl for /dev/snapshot PM / Freezer: fix return value of freezable_schedule_timeout_killable() PM / shmobile: Allow the A4R domain to be turned off at run time PM / input / touchscreen: Make st1232 use device PM QoS constraints PM / QoS: Introduce dev_pm_qos_add_ancestor_request() PM / shmobile: Remove the stay_on flag from SH7372's PM domains PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode PM: Drop generic_subsys_pm_ops PM / Sleep: Remove forward-only callbacks from AMBA bus type PM / Sleep: Remove forward-only callbacks from platform bus type PM: Run the driver callback directly if the subsystem one is not there PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412. PM / Sleep: Merge internal functions in generic_ops.c PM / Sleep: Simplify generic system suspend callbacks PM / Hibernate: Remove deprecated hibernation snapshot ioctls PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled() ARM: S3C64XX: Implement basic power domain support PM / shmobile: Use common always on power domain governor ... Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused XBT_FORCE_SLEEP bit
2012-01-06Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, tsc: Skip TSC synchronization checks for tsc=reliable clocksource: Convert tcb_clksrc to use clocksource_register_hz/khz clocksource: cris: Convert to clocksource_register_khz clocksource: xtensa: Convert to clocksource_register_hz/khz clocksource: um: Convert to clocksource_register_hz/khz clocksource: parisc: Convert to clocksource_register_hz/khz clocksource: m86k: Convert to clocksource_register_hz/khz time: x86: Replace LATCH with PIT_LATCH in i8253 clocksource driver time: x86: Remove CLOCK_TICK_RATE from acpi_pm clocksource driver time: x86: Remove CLOCK_TICK_RATE from mach_timer.h time: x86: Remove CLOCK_TICK_RATE from tsc code time: Fix spelling mistakes in new comments time: fix bogus comment in timekeeping_get_ns_raw
2011-12-11nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu()Frederic Weisbecker
Those two APIs were provided to optimize the calls of tick_nohz_idle_enter() and rcu_idle_enter() into a single irq disabled section. This way no interrupt happening in-between would needlessly process any RCU job. Now we are talking about an optimization for which benefits have yet to be measured. Let's start simple and completely decouple idle rcu and dyntick idle logics to simplify. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11nohz: Allow rcu extended quiescent state handling seperately from tick stopFrederic Weisbecker
It is assumed that rcu won't be used once we switch to tickless mode and until we restart the tick. However this is not always true, as in x86-64 where we dereference the idle notifiers after the tick is stopped. To prepare for fixing this, add two new APIs: tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu(). If no use of RCU is made in the idle loop between tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch must instead call the new *_norcu() version such that the arch doesn't need to call rcu_idle_enter() and rcu_idle_exit(). Otherwise the arch must call tick_nohz_enter_idle() and tick_nohz_exit_idle() and also call explicitly: - rcu_idle_enter() after its last use of RCU before the CPU is put to sleep. - rcu_idle_exit() before the first use of RCU after the CPU is woken up. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: David Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11nohz: Separate out irq exit and idle loop dyntick logicFrederic Weisbecker
The tick_nohz_stop_sched_tick() function, which tries to delay the next timer tick as long as possible, can be called from two places: - From the idle loop to start the dytick idle mode - From interrupt exit if we have interrupted the dyntick idle mode, so that we reprogram the next tick event in case the irq changed some internal state that requires this action. There are only few minor differences between both that are handled by that function, driven by the ts->inidle cpu variable and the inidle parameter. The whole guarantees that we only update the dyntick mode on irq exit if we actually interrupted the dyntick idle mode, and that we enter in RCU extended quiescent state from idle loop entry only. Split this function into: - tick_nohz_idle_enter(), which sets ts->inidle to 1, enters dynticks idle mode unconditionally if it can, and enters into RCU extended quiescent state. - tick_nohz_irq_exit() which only updates the dynticks idle mode when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called). To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed into tick_nohz_idle_exit(). This simplifies the code and micro-optimize the irq exit path (no need for local_irq_save there). This also prepares for the split between dynticks and rcu extended quiescent state logics. We'll need this split to further fix illegal uses of RCU in extended quiescent states in the idle loop. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: David Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-09um: Use $(srctree) not $(KBUILD_SRC)H. Peter Anvin
$(KBUILD_SRC) is not defined without O=, use $(srctree). Reported-and-tested-by: Richard Weinberger <richard@nod.at> Signed-off-by: H. Peter Anvin <hpa@zytor.com>