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2018-02-19Epoll based IRQ controllerAnton Ivanov
1. Removes the need to walk the IRQ/Device list to determine who triggered the IRQ. 2. Improves scalability (up to several times performance improvement for cases with 10s of devices). 3. Improves UML baseline IO performance for one disk + one NIC use case by up to 10%. 4. Introduces write poll triggered IRQs. 5. Prerequisite for introducing high performance mmesg family of functions in network IO. 6. Fixes RNG shutdown which was leaking a file descriptor Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-05uml: Fix unsafe pid reference to foreground process groupPeter Hurley
Although the tty core maintains a pid reference for the foreground process group, if the foreground process group is changed that pid reference is dropped. Thus, the pid reference used for signalling could become stale. Safely obtain a pid reference to the foreground process group and release the reference after signalling is complete. cc: Jeff Dike <jdike@addtoit.com> Acked-by: Richard Weinberger <richard@nod.at> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-21Merge 3.9-rc3 into tty-nextGreg Kroah-Hartman
2013-03-18TTY: add tty_port_tty_wakeup helperJiri Slaby
It allows for cleaning up on a considerable amount of places. They did port_get, wakeup, kref_put. Now the only thing needed is to call tty_port_tty_wakeup which does exactly that. One exception is ifx6x60 where tty_wakeup was open-coded. We now call tty_wakeup properly there. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-11um: Use tty_port in SIGWINCH handlerRichard Weinberger
The tty below tty_port might get destroyed by the tty layer while we hold a reference to it. So we have to carry tty_port around... Signed-off-by: Richard Weinberger <richard@nod.at>
2013-03-11um: Use tty_port_operations->destructRichard Weinberger
As we setup the SIGWINCH handler in tty_port_operations->activate it makes sense to tear down it in ->destruct. Signed-off-by: Richard Weinberger <richard@nod.at>
2013-01-15TTY: switch tty_flip_buffer_pushJiri Slaby
Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15TTY: call tty_port_destroy in the rest of driversJiri Slaby
After commit "TTY: move tty buffers to tty_port", the tty buffers are not freed in some drivers. This is because tty_port_destructor is not called whenever a tty_port is freed. This was an assumption I counted with but was unfortunately untrue. So fix the drivers to fulfil this assumption. To be sure, the TTY buffers (and later some stuff) are gone along with the tty_port, we have to call tty_port_destroy at tear-down places. This is mostly where the structure containing a tty_port is freed. This patch does exactly that -- put tty_port_destroy at those places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-10Merge branch 'for-linus-37rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML changes from Richard Weinberger: "UML receives this time only cleanups. The most outstanding change is the 'include "foo.h"' do 'include <foo.h>' conversion done by Al Viro. It touches many files, that's why the diffstat is rather big." * 'for-linus-37rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: typo in UserModeLinux-HOWTO hppfs: fix the return value of get_inode() hostfs: drop vmtruncate um: get rid of pointless include "..." where include <...> will do um: move sysrq.h out of include/shared um/x86: merge 32 and 64 bit variants of ptrace.h um/x86: merge 32 and 64bit variants of checksum.h
2012-10-09um: get rid of pointless include "..." where include <...> will doAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2012-08-13TTY: use tty_port_register_deviceJiri Slaby
Currently we have no way to assign tty->port while performing tty installation. There are two ways to provide the link tty_struct => tty_port. Either by calling tty_port_install from tty->ops->install or tty_port_register_device called instead of tty_register_device when the device is being set up after connected. In this patch we modify most of the drivers to do the latter. When the drivers use tty_register_device and we have tty_port already, we switch to tty_port_register_device. So we have the tty_struct => tty_port link for free for those. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-01Merge branch 'for-linus-3.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML fixes from Richard Weinberger: "This patch set contains mostly fixes and cleanups. The UML tty driver uses now tty_port and is no longer broken like hell :-)" * 'for-linus-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: Add arch/x86/um to MAINTAINERS um: pass siginfo to guest process um: fix ubd_file_size for read-only files um: pull interrupt_end() into userspace() um: split syscall_trace(), pass pt_regs to it um: switch UPT_SET_RETURN_VALUE and regs_return_value to pt_regs um: set BLK_CGROUP=y in defconfig um: remove count_lock um: fully use tty_port um: Remove dead code um: remove line_ioctl() TTY: um/line, use tty from tty_port TTY: um/line, add tty_port
2012-07-28um: remove count_lockRichard Weinberger
this lock is no longer needed. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-07-28um: fully use tty_portRichard Weinberger
... use all tty_port helpers Signed-off-by: Richard Weinberger <richard@nod.at>
2012-07-28um: remove line_ioctl()Richard Weinberger
line_ioctl() has no real function. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-07-28TTY: um/line, use tty from tty_portJiri Slaby
This means switching to the tty refcounted model so that we will not race with interrupts. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: user-mode-linux-devel@lists.sourceforge.net Signed-off-by: Richard Weinberger <richard@nod.at>
2012-07-28TTY: um/line, add tty_portJiri Slaby
And use count from there. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: user-mode-linux-devel@lists.sourceforge.net Signed-off-by: Richard Weinberger <richard@nod.at>
2012-07-19um: remove IRQF_SAMPLE_RANDOM which is now a no-opTheodore Ts'o
With the changes in the random tree, IRQF_SAMPLE_RANDOM is now a no-op; interrupt randomness is now collected unconditionally in a very low-overhead fashion; see commit 775f4b297b. The IRQF_SAMPLE_RANDOM flag was scheduled to be removed in 2009 on the feature-removal-schedule, so this patch is preparation for the final removal of this flag. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at>
2012-05-21um: Implement um_free_irq()Richard Weinberger
Instead of using chip->release() we can achieve the same using a simple wrapper for free_irq(). We have already um_request_irq(), so um_free_irq() is the perfect counterpart. Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
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: 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: 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: 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: 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>
2011-11-02um: take chan_*.h and line.h to arch/um/driversAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-09-14um: fix free_winch() messAl Viro
while not doing free_irq() from irq handler is commendable, kfree() on the data passed to said handler before free_irq() is Not Good(tm). Freeing the stack it's being run on is also not nice... Solution: delay actually freeing stuff. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14um: winch_interrupt() can happen inside of free_winch()Al Viro
... so set winch->fd to -1 before doing free_irq(), to avoid having winch_interrupt() come from/during the latter and attempt to do reactivate_fd() on something that's already gone. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14um: fix oopsable race in line_close()Al Viro
tty->count is decremented only after ->close() had been called and several tasks can hit it in parallel. As the result, using tty->count to check if you are the last one is broken. We end up leaving line->tty not reset to NULL and the next IRQ on that sucker will blow up trying to dereference pointers from kfree'd struct tty. Fix is obvious: we need to use a counter of our own. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25um: remove dead codeRichard Weinberger
GCC 4.6's -Wunused-but-set-variable found some dead code. Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22um: remove file pointer from ioctlRichard Weinberger
Commit 6caa76b ("tty: now phase out the ioctl file pointer for good") removed the ioctl file pointer. User Mode Linux's line driver uses this ioctl and needs a signature update too. Signed-off-by: Richard Weinberger <richard@nod.at> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Greg KH <greg@kroah.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13arch/um/drivers/line.c: safely iterate over list of winch handlersWill Newton
unregister_winch() should use list_for_each_safe(), as it can delete from the list. Signed-off-by: Will Newton <will.newton@gmail.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-25uml: disable winch irq before freeing handler dataWill Newton
Disable the winch irq early to make sure we don't take an interrupt part way through the freeing of the handler data, resulting in a crash on shutdown: winch_interrupt : read failed, errno = 9 fd 13 is losing SIGWINCH support ------------[ cut here ]------------ WARNING: at lib/list_debug.c:48 list_del+0xc6/0x100() list_del corruption, next is LIST_POISON1 (00100100) 082578c8: [<081fd77f>] dump_stack+0x22/0x24 082578e0: [<0807a18a>] warn_slowpath_common+0x5a/0x80 08257908: [<0807a23e>] warn_slowpath_fmt+0x2e/0x30 08257920: [<08172196>] list_del+0xc6/0x100 08257940: [<08060244>] free_winch+0x14/0x80 08257958: [<080606fb>] winch_interrupt+0xdb/0xe0 08257978: [<080a65b5>] handle_IRQ_event+0x35/0xe0 08257998: [<080a8717>] handle_edge_irq+0xb7/0x170 082579bc: [<08059bc4>] do_IRQ+0x34/0x50 082579d4: [<08059e1b>] sigio_handler+0x5b/0x80 082579ec: [<0806a374>] sig_handler_common+0x44/0xb0 08257a68: [<0806a538>] sig_handler+0x38/0x50 08257a78: [<0806a77c>] handle_signal+0x5c/0xa0 08257a9c: [<0806be28>] hard_handler+0x18/0x20 08257aac: [<00c14400>] 0xc14400 Signed-off-by: Will Newton <will.newton@gmail.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits) vlynq: make whole Kconfig-menu dependant on architecture add descriptive comment for TIF_MEMDIE task flag declaration. EEPROM: max6875: Header file cleanup EEPROM: 93cx6: Header file cleanup EEPROM: Header file cleanup agp: use NULL instead of 0 when pointer is needed rtc-v3020: make bitfield unsigned PCI: make bitfield unsigned jbd2: use NULL instead of 0 when pointer is needed cciss: fix shadows sparse warning doc: inode uses a mutex instead of a semaphore. uml: i386: Avoid redefinition of NR_syscalls fix "seperate" typos in comments cocbalt_lcdfb: correct sections doc: Change urls for sparse Powerpc: wii: Fix typo in comment i2o: cleanup some exit paths Documentation/: it's -> its where appropriate UML: Fix compiler warning due to missing task_struct declaration UML: add kernel.h include to signal.c ...
2010-04-20UML: Remove unused variable from line driverJan Kiszka
Signed-off-by: Jan Kiszka <jan.kiszka@web.de> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-04-19uml: Fix build breakage after slab.h changesJan Kiszka
We now have to to include linux/slab.h explicitly for kmalloc & friends. Files that build against host headers already get their prototypes via um_malloc.h, linux/slab.h may even be unavailable. Signed-off-by: Jan Kiszka <jan.kiszka@web.de> Signed-off-by: Tejun Heo <tj@kernel.org>
2010-03-06uml: line.c: avoid NULL pointer dereferenceAlexander Beregalov
Assign tty only if line is not NULL. [akpm@linux-foundation.org: simplification] Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-11headers: remove sched.h from interrupt.hAlexey Dobriyan
After m68k's task_thread_info() doesn't refer to current, it's possible to remove sched.h from interrupt.h and not break m68k! Many thanks to Heiko Carstens for allowing this. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2008-10-13uml: small cleanups and note bugs to be dealt with by uml authors...Alan Cox
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-30uml: fix tty-related build errorWANG Cong
/home/wangcong/Projects/linux-2.6/arch/um/drivers/line.c: In function `line_write_interrupt': /home/wangcong/Projects/linux-2.6/arch/um/drivers/line.c:366: error: `struct tty_ldisc' has no member named `write_wakeup' /home/wangcong/Projects/linux-2.6/arch/um/drivers/line.c:367: error: `struct tty_ldisc' has no member named `write_wakeup' Signed-off-by: WANG Cong <wangcong@zeuux.org> Cc: Jeff Dike <jdike@addtoit.com> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-08uml: fix inconsistence due to tty_operation changeWANG Cong
'put_char' of 'struct tty_operations' has changed from 'void' into 'int'. This can also shut up compiler warnings. Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: WANG Cong <wangcong@zeuux.org> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>