Use irq_set_handler_locked() as it avoids a redundant lookup of the
irq descriptor. Search and replacement was done with coccinelle:
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Use irq_set_handler_locked() as it avoids a redundant lookup of the
irq descriptor.
Search and replacement was done with coccinelle:
@@
struct irq_data *d;
expression E1;
@@
-__irq_set_handler_locked(d->irq, E1);
+irq_set_handler_locked(d, E1);
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Use irq_set_handler_locked() as it avoids a redundant lookup of the
irq descriptor.
Search and replacement was done with coccinelle:
@@
struct irq_data *d;
expression E1;
@@
-__irq_set_handler_locked(d->irq, E1);
+irq_set_handler_locked(d, E1);
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Anton Blanchard <anton@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Use irq_set_handler_locked() as it avoids a redundant lookup of the
irq descriptor.
Search and replacement was done with coccinelle:
@@
struct irq_data *d;
expression E1;
@@
-__irq_set_handler_locked(d->irq, E1);
+irq_set_handler_locked(d, E1);
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Use irq_set_handler_locked() as it avoids a redundant lookup of the
irq descriptor.
Search and replacement was done with coccinelle:
@@
struct irq_data *d;
expression E1;
@@
-__irq_set_handler_locked(d->irq, E1);
+irq_set_handler_locked(d, E1);
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
__irq_set_chip_handler_name_locked() is about to be replaced. Use
irq_set_chip_handler_name_locked() instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
The renesas-irqc interrupt controller is cascaded to the GIC, but its
driver doesn't propagate wake-up settings to the parent interrupt
controller.
Since commit aec89ef72b ("irqchip/gic: Enable SKIP_SET_WAKE and
MASK_ON_SUSPEND"), the GIC driver masks interrupts during suspend, and
wake-up through gpio-keys now fails on r8a73a4/ape6evm.
Fix this by propagating wake-up settings to the parent interrupt
controller. There's no need to handle irq_set_irq_wake() failures, as
the renesas-irqc interrupt controller is always cascaded to a GIC, and
the GIC driver always sets SKIP_SET_WAKE since the aforementioned
commit.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1441731636-17610-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The renesas-intc-irqpin interrupt controller is cascaded to the GIC, but
its driver doesn't propagate wake-up settings to the parent interrupt
controller.
Since commit aec89ef72b ("irqchip/gic: Enable SKIP_SET_WAKE and
MASK_ON_SUSPEND"), the GIC driver masks interrupts during suspend, and
wake-up through gpio-keys now fails on r8a7740/armadillo and
sh73a0/kzm9g.
Fix this by propagating wake-up settings to the parent interrupt
controller. There's no need to handle irq_set_irq_wake() failures, as
the renesas-intc-irqpin interrupt controller is always cascaded to a
GIC, and the GIC driver always sets SKIP_SET_WAKE since the
aforementioned commit.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1441731636-17610-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:
=============================================
[ INFO: possible recursive locking detected ]
4.2.0-armadillo-10725-g50fcd7643c034198 #781 Not tainted
---------------------------------------------
s2ram/1179 is trying to acquire lock:
(&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94
but task is already holding lock:
(&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&irq_desc_lock_class);
lock(&irq_desc_lock_class);
*** DEADLOCK ***
May be due to missing lock nesting notation
7 locks held by s2ram/1179:
#0: (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
#1: (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
#2: (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
#3: (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
#4: (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
#5: (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
#6: (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94
stack backtrace:
CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198
Hardware name: Generic R8A7740 (Flattened Device Tree)
[<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
[<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
[<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
[<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
[<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
[<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
[<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
[<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
[<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
[<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
[<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
[<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)
Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The renesas-irqc interrupt controller is cascaded to the GIC. Hence when
propagating wake-up settings to its parent interrupt controller, the
following lockdep warning is printed:
=============================================
[ INFO: possible recursive locking detected ]
4.2.0-ape6evm-10725-g50fcd7643c034198 #280 Not tainted
---------------------------------------------
s2ram/1072 is trying to acquire lock:
(&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98
but task is already holding lock:
(&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&irq_desc_lock_class);
lock(&irq_desc_lock_class);
*** DEADLOCK ***
May be due to missing lock nesting notation
6 locks held by s2ram/1072:
#0: (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8
#1: (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc
#2: (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc
#3: (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510
#4: (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc
#5: (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98
stack backtrace:
CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 #280
Hardware name: Generic R8A73A4 (Flattened Device Tree)
[<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14)
[<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98)
[<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4)
[<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c)
[<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54)
[<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98)
[<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8)
[<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c)
[<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8)
[<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0)
[<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124)
Avoid this false positive by using a separate lockdep class for IRQC
interrupts.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
After GICv2m was enabled for 32-bit ARM kernel, a warning popped up:
drivers/irqchip/irq-gic-v2m.c: In function gicv2m_compose_msi_msg:
drivers/irqchip/irq-gic-v2m.c💯2: warning: right shift count >= width
of type [enabled by default]
msg->address_hi = (u32) (addr >> 32);
^
This patch fixes it by using proper macros for splitting up the value.
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Stuart Yoder <stuart.yoder@freescale.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1442142873-20213-4-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When the ITS is configured for non-cacheable transactions, make sure
that the allocated, zeroed memory is flushed to the Point of
Coherency, allowing the ITS to observe the zeros instead of random
garbage (or even get its own data overwritten by zeros being evicted
from the cache...).
Fixes: 241a386c7d "irqchip: gicv3-its: Use non-cacheable accesses when no shareability"
Reported-and-tested-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Pavel Fedin <p.fedin@samsung.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1442142873-20213-3-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The GICv2 architecture mandates that the two 4kB GIC regions are
contiguous, and on two separate physical pages (so that access to
the second page can be trapped by a hypervisor). This doesn't work
very well when PAGE_SIZE is 64kB.
A relatively common hack^Wway to work around this is to alias each
4kB region over its own 64kB page. Of course in this case, the base
address you want to use is not really the begining of the region,
but base + 60kB (so that you get a contiguous 8kB region over two
distinct pages).
Normally, this would be described in DT with a new property, but
some HW is already out there, and the firmware makes sure that
it will override whatever you put in the GIC node. Duh. And of course,
said firmware source code is not available, despite being based
on u-boot.
The workaround is to detect the case where the CPU interface size
is set to 128kB, and verify the aliasing by checking that the ID
register for GIC400 (which is the only GIC wired this way so far)
is the same at base and base + 0xF000. In this case, we update
the GIC base address and let it roll.
And if you feel slightly sick by looking at this, rest assured that
I do too...
Reported-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Stuart Yoder <stuart.yoder@freescale.com>
Cc: Pavel Fedin <p.fedin@samsung.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1442142873-20213-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The current implementation of platform MSI caches the msi_desc
pointer in irq_data::handler_data. This is a bit silly, as
we also have irq_data::msi_desc, which is perfectly valid.
Remove the useless assignment and simplify the whole flow.
Reported-by: Ma Jun <majun258@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Link: http://lkml.kernel.org/r/1442147824-20971-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This is a preparatory patch for moving irq_data struct members. Search
and replace was done with coccinelle
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Amir Vadai <amirv@mellanox.com>
The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Search and replace done with coccinelle
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linuxppc-dev@lists.ozlabs.org
The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: linuxppc-dev@lists.ozlabs.org
The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linuxppc-dev@lists.ozlabs.org
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
iEYEABECAAYFAlXqI2YACgkQ31LbvUHyf1eV9QCdH1QQrv3ze1j+5ut3hVGQFC7F
s0oAnRWfi65O5J6Ns4gEGfbjSXvF2aNf
=5RcU
-----END PGP SIGNATURE-----
Merge tag 'cris-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper/cris
Pull CRIS updates from Jesper Nilsson:
"Mostly removal of old cruft of which we can use a generic version, or
fixes for code not commonly run in the cris port, but also additions
to enable some good debug"
* tag 'cris-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper/cris: (25 commits)
CRISv10: delete unused lib/dmacopy.c
CRISv10: delete unused lib/old_checksum.c
CRIS: fix switch_mm() lockdep splat
CRISv32: enable LOCKDEP_SUPPORT
CRIS: add STACKTRACE_SUPPORT
CRISv32: annotate irq enable in idle loop
CRISv32: add support for irqflags tracing
CRIS: UAPI: use generic types.h
CRIS: UAPI: use generic shmbuf.h
CRIS: UAPI: use generic msgbuf.h
CRIS: UAPI: use generic socket.h
CRIS: UAPI: use generic sembuf.h
CRIS: UAPI: use generic sockios.h
CRIS: UAPI: use generic auxvec.h
CRIS: UAPI: use generic headers via Kbuild
CRIS: UAPI: fix elf.h export
CRIS: don't make asm/elf.h depend on asm/user.h
CRIS: UAPI: fix ptrace.h
CRISv32: Squash compile warnings for axisflashmap
CRISv32: Add GPIO driver to the default configs
...
rq_data_dir() returns either READ or WRITE (0 == READ, 1 == WRITE), not
a boolean value.
Now, admittedly the "!= 0" doesn't really change the value (0 stays as
zero, 1 stays as one), but it's not only redundant, it confuses gcc, and
causes gcc to warn about the construct
switch (rq_data_dir(req)) {
case READ:
...
case WRITE:
...
that we have in a few drivers.
Now, the gcc warning is silly and stupid (it seems to warn not about the
switch value having a different type from the case statements, but about
_any_ boolean switch value), but in this case the code itself is silly
and stupid too, so let's just change it, and get rid of warnings like
this:
drivers/block/hd.c: In function ‘hd_request’:
drivers/block/hd.c:630:11: warning: switch condition has boolean value [-Wswitch-bool]
switch (rq_data_dir(req)) {
The odd '!= 0' came in when "cmd_flags" got turned into a "u64" in
commit 5953316dbf ("block: make rq->cmd_flags be 64-bit") and is
presumably because the old code (that just did a logical 'and' with 1)
would then end up making the type of rq_data_dir() be u64 too.
But if we want to retain the old regular integer type, let's just cast
the result to 'int' rather than use that rather odd '!= 0'.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up the writeback plugging introduced in commit d353d7587d
("writeback: plug writeback at a high level") that then caused problems
due to the unplug happening with a spinlock held.
* writeback-plugging:
writeback: plug writeback in wb_writeback() and writeback_inodes_wb()
Revert "writeback: plug writeback at a high level"
We had to revert the pluggin in writeback_sb_inodes() because the
wb->list_lock is held, but we could easily plug at a higher level before
taking that lock, and unplug after releasing it. This does that.
Chris will run performance numbers, just to verify that this approach is
comparable to the alternative (we could just drop and re-take the lock
around the blk_finish_plug() rather than these two commits.
I'd have preferred waiting for actual performance numbers before picking
one approach over the other, but I don't want to release rc1 with the
known "sleeping function called from invalid context" issue, so I'll
pick this cleanup version for now. But if the numbers show that we
really want to plug just at the writeback_sb_inodes() level, and we
should just play ugly games with the spinlock, we'll switch to that.
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I didn't notice this when merging the thermal code from Zhang, but his
merge (commit 5a924a07f882: "Merge branches 'thermal-core' and
'thermal-intel' of .git into next") of the thermal-core and
thermal-intel branches was wrong.
In thermal-core, commit 17e8351a77 ("thermal: consistently use int for
temperatures") converted the thermal layer to use "int" for
temperatures.
But in parallel, in the thermal-intel branch commit d0a12625d2
("thermal: Add Intel PCH thermal driver") added support for the intel
PCH thermal sensor using the old interfaces that used "unsigned long"
pointers.
This resulted in warnings like this:
drivers/thermal/intel_pch_thermal.c:184:14: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
.get_temp = pch_thermal_get_temp,
^
drivers/thermal/intel_pch_thermal.c:184:14: note: (near initialization for ‘tzd_ops.get_temp’)
drivers/thermal/intel_pch_thermal.c:186:19: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
.get_trip_temp = pch_get_trip_temp,
^
drivers/thermal/intel_pch_thermal.c:186:19: note: (near initialization for ‘tzd_ops.get_trip_temp’)
This fixes it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge fourth patch-bomb from Andrew Morton:
- sys_membarier syscall
- seq_file interface changes
- a few misc fixups
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each"
mm/early_ioremap: add explicit #include of asm/early_ioremap.h
fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void
selftests: enhance membarrier syscall test
selftests: add membarrier syscall test
sys_membarrier(): system-wide memory barrier (generic, x86)
MODSIGN: fix a compilation warning in extract-cert
improvements, and adding a mailing list to MAINTAINERS for NTB.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=CASz
-----END PGP SIGNATURE-----
Merge tag 'ntb-4.3' of git://github.com/jonmason/ntb
Pull NTB fixes from Jon Mason:
"NTB bug and documentation fixes, new device IDs, performance
improvements, and adding a mailing list to MAINTAINERS for NTB"
* tag 'ntb-4.3' of git://github.com/jonmason/ntb:
NTB: Fix range check on memory window index
NTB: Improve index handling in B2B MW workaround
NTB: Fix documentation for ntb_peer_db_clear.
NTB: Fix documentation for ntb_link_is_up
NTB: Use unique DMA channels for TX and RX
NTB: Remove dma_sync_wait from ntb_async_rx
NTB: Clean up QP stats info
NTB: Make the transport list in order of discovery
NTB: Add PCI Device IDs for Broadwell Xeon
NTB: Add flow control to the ntb_netdev
NTB: Add list to MAINTAINERS
Pull more input updates from Dmitry Torokhov:
"Second round of updates for the input subsystem.
This introduces two brand new touchscreen drivers (Colibri and
imx6ul_tsc), some small driver fixes, and we are no longer report
errors from evdev_flush() as users do not really have a way of
handling errors, error codes that we were returning were not on the
list of errors supposed to be returned by close(), and errors were
causing issues with one of older versions of systemd"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: imx_keypad - remove obsolete comment
Input: touchscreen - add imx6ul_tsc driver support
Input: Add touchscreen support for Colibri VF50
Input: i8042 - lower log level for "no controller" message
Input: evdev - do not report errors form flush()
Input: elants_i2c - extend the calibration timeout to 12 seconds
Input: sparcspkr - fix module autoload for OF platform drivers
Input: regulator-haptic - fix module autoload for OF platform driver
Input: pwm-beeper - fix module autoload for OF platform driver
Input: ab8500-ponkey - Fix module autoload for OF platform driver
Input: cyttsp - remove unnecessary MODULE_ALIAS()
Input: elan_i2c - add ACPI ID "ELAN1000"
- Build fix for the new Mediatek MT8173 cpufreq driver (Guenter Roeck).
- Generic power domains framework fixes (power on error code
path, subdomain removal) and cleanup of a deprecated API user
(Geert Uytterhoeven, Jon Hunter, Ulf Hansson).
- cpufreq-dt driver fixes including two fixes for bugs related to
the new Operating Performance Points Device Tree bindings
introduced recently (Viresh Kumar).
- Suspend frequency support for the cpufreq-dt driver
(Bartlomiej Zolnierkiewicz, Viresh Kumar).
- cpufreq core cleanups (Viresh Kumar).
- intel_pstate driver fixes (Chen Yu, Kristen Carlson Accardi).
- Additional sanity check in the cpuidle core (Xunlei Pang).
- Fix for a comment related to CPU power management (Lina Iyer).
/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=C7+4
-----END PGP SIGNATURE-----
Merge tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management and ACPI updates from Rafael Wysocki:
"These are mostly fixes and cleanups on top of the previous PM+ACPI
pull request (cpufreq core and drivers, cpuidle, generic power domains
framework). Some of them didn't make to that pull request and some
fix issues introduced by it.
The only really new thing is the support for suspend frequency in the
cpufreq-dt driver, but it is needed to fix an issue with Exynos
platforms.
Specifics:
- build fix for the new Mediatek MT8173 cpufreq driver (Guenter
Roeck).
- generic power domains framework fixes (power on error code path,
subdomain removal) and cleanup of a deprecated API user (Geert
Uytterhoeven, Jon Hunter, Ulf Hansson).
- cpufreq-dt driver fixes including two fixes for bugs related to the
new Operating Performance Points Device Tree bindings introduced
recently (Viresh Kumar).
- suspend frequency support for the cpufreq-dt driver (Bartlomiej
Zolnierkiewicz, Viresh Kumar).
- cpufreq core cleanups (Viresh Kumar).
- intel_pstate driver fixes (Chen Yu, Kristen Carlson Accardi).
- additional sanity check in the cpuidle core (Xunlei Pang).
- fix for a comment related to CPU power management (Lina Iyer)"
* tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
intel_pstate: fix PCT_TO_HWP macro
intel_pstate: Fix user input of min/max to legal policy region
PM / OPP: Return suspend_opp only if it is enabled
cpufreq-dt: add suspend frequency support
cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
PM / OPP: add dev_pm_opp_get_suspend_opp() helper
staging: board: Migrate away from __pm_genpd_name_add_device()
cpufreq: Use __func__ to print function's name
cpufreq: staticize cpufreq_cpu_get_raw()
PM / Domains: Ensure subdomain is not in use before removing
cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL
cpuidle/coupled: Add sanity check for safe_state_index
PM / Domains: Try power off masters in error path of __pm_genpd_poweron()
cpufreq: dt: Tolerance applies on both sides of target voltage
cpufreq: dt: Print error on failing to mark OPPs as shared
cpufreq: dt: Check OPP count before marking them shared
kernel/cpu_pm: fix cpu_cluster_pm_exit comment
Pull SCSI target updates from Nicholas Bellinger:
"Here are the outstanding target-pending updates for v4.3-rc1.
Mostly bug-fixes and minor changes this round. The fallout from the
big v4.2-rc1 RCU conversion have (thus far) been minimal.
The highlights this round include:
- Move sense handling routines into scsi_common code (Sagi)
- Return ABORTED_COMMAND sense key for PI errors (Sagi)
- Add tpg_enabled_sendtargets attribute for disabled iscsi-target
discovery (David)
- Shrink target struct se_cmd by rearranging fields (Roland)
- Drop iSCSI use of mutex around max_cmd_sn increment (Roland)
- Replace iSCSI __kernel_sockaddr_storage with sockaddr_storage (Andy +
Chris)
- Honor fabric max_data_sg_nents I/O transfer limit (Arun + Himanshu +
nab)
- Fix EXTENDED_COPY >= v4.1 regression OOPsen (Alex + nab)"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (37 commits)
target: use stringify.h instead of own definition
target/user: Fix UFLAG_UNKNOWN_OP handling
target: Remove no-op conditional
target/user: Remove unused variable
target: Fix max_cmd_sn increment w/o cmdsn mutex regressions
target: Attach EXTENDED_COPY local I/O descriptors to xcopy_pt_sess
target/qla2xxx: Honor max_data_sg_nents I/O transfer limit
target/iscsi: Replace __kernel_sockaddr_storage with sockaddr_storage
target/iscsi: Replace conn->login_ip with login_sockaddr
target/iscsi: Keep local_ip as the actual sockaddr
target/iscsi: Fix np_ip bracket issue by removing np_ip
target: Drop iSCSI use of mutex around max_cmd_sn increment
qla2xxx: Update tcm_qla2xxx module description to 24xx+
iscsi-target: Add tpg_enabled_sendtargets for disabled discovery
drivers: target: Drop unlikely before IS_ERR(_OR_NULL)
target: check DPO/FUA usage for COMPARE AND WRITE
target: Shrink struct se_cmd by rearranging fields
target: Remove cmd->se_ordered_id (unused except debug log lines)
target: add support for START_STOP_UNIT SCSI opcode
target: improve unsupported opcode message
...
The major pieces of this patch are a set patches facilitating better
integration between scsi and scsi_dh (the device handling layer used by
multi-path; all the dm parts are acked by Mike Snitzer). It also includes
driver updates for mp3sas, scsi_debug and an assortment of bug fixes.
Signed-off-by: James Bottomley <JBottomley@Odin.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iQEcBAABAgAGBQJV8yt5AAoJEDeqqVYsXL0MBsQH+wXvlx3o0BGuz5ZXfIs/RxzI
MwGnu1J0LSA9FPakkMUVOBtsxIG+pCV+4eKorQMkfGCKAZ8daaYsyYvSEM2mcqIX
1Y/srEnbzfE94JHbsI2pbiMPkB7QdtW27WjTSjQGgD9igAyVmmITiQJrXbpAlSLF
F6n++9avng+GhjXQ5TF8/y13OYgabIoAPM1j4B/ut/Ok8ReruBvMBnOla5w5RMKR
rBZKTZfUwvX5S0cuREwj8tFsRVUgdBNSrcGswFJrZo5x9WAsSHLC6+SOLZuUy1vC
ua0tNtEiyXiuR0/jSP9qv7hJ/j0BW+EGdnW6GZEzKpeMK5PxfVspOsbNunUDRsY=
=Y9G1
-----END PGP SIGNATURE-----
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull second round of SCSI updates from James Bottomley:
"There's one late arriving patch here (added today), fixing a build
issue which the scsi_dh patch set in here uncovered. Other than that,
everything has been incubated in -next and the checkers for a week.
The major pieces of this patch are a set patches facilitating better
integration between scsi and scsi_dh (the device handling layer used
by multi-path; all the dm parts are acked by Mike Snitzer).
This also includes driver updates for mp3sas, scsi_debug and an
assortment of bug fixes"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (50 commits)
scsi_dh: fix randconfig build error
scsi: fix scsi_error_handler vs. scsi_host_dev_release race
fcoe: Convert use of __constant_htons to htons
mpt2sas: setpci reset kernel oops fix
pm80xx: Don't override ts->stat on IO_OPEN_CNX_ERROR_HW_RESOURCE_BUSY
lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2()
bfa: Fix incorrect de-reference of pointer
bfa: Fix indentation
scsi_transport_sas: Remove check for SAS expander when querying bay/enclosure IDs.
scsi_debug: resp_request: remove unused variable
scsi_debug: fix REPORT LUNS Well Known LU
scsi_debug: schedule_resp fix input variable check
scsi_debug: make dump_sector static
scsi_debug: vfree is null safe so drop the check
scsi_debug: use SCSI_W_LUN_REPORT_LUNS instead of SAM2_WLUN_REPORT_LUNS;
scsi_debug: define pr_fmt() for consistent logging
mpt2sas: Refcount fw_events and fix unsafe list usage
mpt2sas: Refcount sas_device objects and fix unsafe list usage
scsi_dh: return SCSI_DH_NOTCONN in scsi_dh_activate()
scsi_dh: don't allow to detach device handlers at runtime
...
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=TEFw
-----END PGP SIGNATURE-----
Merge tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
"A series of patches that move part of the code used to allocate memory
from the media subsystem to the mm subsystem"
[ The mm parts have been acked by VM people, and the series was
apparently in -mm for a while - Linus ]
* tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames()
[media] media: vb2: Remove unused functions
[media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector
[media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector
[media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector
[media] vb2: Provide helpers for mapping virtual addresses
[media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
[media] mm: Provide new get_vaddr_frames() helper
[media] vb2: Push mmap_sem down to memops
Pull thermal updates from Zhang Rui:
- use int instead of unsigned long to represent temperature to avoid
bogus overheat detection when negative temperature reported. From
Sascha Hauer.
- export available thermal governors information to user space via
sysfs. From Wei Ni.
- introduce new thermal driver for Wildcat Point platform controller
hub, which uses PCH thermal sensor and associated critical and hot
trip points. From Tushar Dave.
- add suuport for Intel Skylake and Denlow platforms in powerclamp
driver.
- some small cleanups in thermal core.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal: Add Intel PCH thermal driver
thermal: Add comment explaining test for critical temperature
thermal: Use IS_ENABLED instead of #ifdef
thermal: remove unnecessary call to thermal_zone_device_set_polling
thermal: trivial: fix typo in comment
thermal: consistently use int for temperatures
thermal: add available policies sysfs attribute
thermal/powerclamp: add cpu id for denlow platform
thermal/powerclamp: add cpu id for Skylake u/y
thermal/powerclamp: add cpu id for skylake h/s
Revert commit f83c7b5e9f ("ocfs2/dlm: use list_for_each_entry instead
of list_for_each").
list_for_each_entry() will dereference its `pos' argument, which can be
NULL in dlm_process_recovery_data().
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Fengguang Wu <fengguang.wu@gmail.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 6b0f68e32e ("mm: add utility for early copy from unmapped ram")
introduces a function copy_from_early_mem() into mm/early_ioremap.c
which itself calls early_memremap()/early_memunmap(). However, since
early_memunmap() has not been declared yet at this point in the .c file,
nor by any explicitly included header files, we are depending on a
transitive include of asm/early_ioremap.h to declare it, which is
fragile.
So instead, include this header explicitly.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The seq_<foo> function return values were frequently misused.
See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
seq_has_overflowed() and make public")
All uses of these return values have been removed, so convert the
return types to void.
Miscellanea:
o Move seq_put_decimal_<type> and seq_escape prototypes closer the
other seq_vprintf prototypes
o Reorder seq_putc and seq_puts to return early on overflow
o Add argument names to seq_vprintf and seq_printf
o Update the seq_escape kernel-doc
o Convert a couple of leading spaces to tabs in seq_escape
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update the membarrier syscall self-test to match the membarrier
interface. Extend coverage of the interface. Consider ENOSYS as a
"SKIP" test, since it is a valid configuration, but does not allow
testing the system call.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Pranith Kumar <bobby.prani@gmail.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a self test for the membarrier system call.
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is an implementation of a new system call, sys_membarrier(), which
executes a memory barrier on all threads running on the system. It is
implemented by calling synchronize_sched(). It can be used to
distribute the cost of user-space memory barriers asymmetrically by
transforming pairs of memory barriers into pairs consisting of
sys_membarrier() and a compiler barrier. For synchronization primitives
that distinguish between read-side and write-side (e.g. userspace RCU
[1], rwlocks), the read-side can be accelerated significantly by moving
the bulk of the memory barrier overhead to the write-side.
The existing applications of which I am aware that would be improved by
this system call are as follows:
* Through Userspace RCU library (http://urcu.so)
- DNS server (Knot DNS) https://www.knot-dns.cz/
- Network sniffer (http://netsniff-ng.org/)
- Distributed object storage (https://sheepdog.github.io/sheepdog/)
- User-space tracing (http://lttng.org)
- Network storage system (https://www.gluster.org/)
- Virtual routers (https://events.linuxfoundation.org/sites/events/files/slides/DPDK_RCU_0MQ.pdf)
- Financial software (https://lkml.org/lkml/2015/3/23/189)
Those projects use RCU in userspace to increase read-side speed and
scalability compared to locking. Especially in the case of RCU used by
libraries, sys_membarrier can speed up the read-side by moving the bulk of
the memory barrier cost to synchronize_rcu().
* Direct users of sys_membarrier
- core dotnet garbage collector (https://github.com/dotnet/coreclr/issues/198)
Microsoft core dotnet GC developers are planning to use the mprotect()
side-effect of issuing memory barriers through IPIs as a way to implement
Windows FlushProcessWriteBuffers() on Linux. They are referring to
sys_membarrier in their github thread, specifically stating that
sys_membarrier() is what they are looking for.
To explain the benefit of this scheme, let's introduce two example threads:
Thread A (non-frequent, e.g. executing liburcu synchronize_rcu())
Thread B (frequent, e.g. executing liburcu
rcu_read_lock()/rcu_read_unlock())
In a scheme where all smp_mb() in thread A are ordering memory accesses
with respect to smp_mb() present in Thread B, we can change each
smp_mb() within Thread A into calls to sys_membarrier() and each
smp_mb() within Thread B into compiler barriers "barrier()".
Before the change, we had, for each smp_mb() pairs:
Thread A Thread B
previous mem accesses previous mem accesses
smp_mb() smp_mb()
following mem accesses following mem accesses
After the change, these pairs become:
Thread A Thread B
prev mem accesses prev mem accesses
sys_membarrier() barrier()
follow mem accesses follow mem accesses
As we can see, there are two possible scenarios: either Thread B memory
accesses do not happen concurrently with Thread A accesses (1), or they
do (2).
1) Non-concurrent Thread A vs Thread B accesses:
Thread A Thread B
prev mem accesses
sys_membarrier()
follow mem accesses
prev mem accesses
barrier()
follow mem accesses
In this case, thread B accesses will be weakly ordered. This is OK,
because at that point, thread A is not particularly interested in
ordering them with respect to its own accesses.
2) Concurrent Thread A vs Thread B accesses
Thread A Thread B
prev mem accesses prev mem accesses
sys_membarrier() barrier()
follow mem accesses follow mem accesses
In this case, thread B accesses, which are ensured to be in program
order thanks to the compiler barrier, will be "upgraded" to full
smp_mb() by synchronize_sched().
* Benchmarks
On Intel Xeon E5405 (8 cores)
(one thread is calling sys_membarrier, the other 7 threads are busy
looping)
1000 non-expedited sys_membarrier calls in 33s =3D 33 milliseconds/call.
* User-space user of this system call: Userspace RCU library
Both the signal-based and the sys_membarrier userspace RCU schemes
permit us to remove the memory barrier from the userspace RCU
rcu_read_lock() and rcu_read_unlock() primitives, thus significantly
accelerating them. These memory barriers are replaced by compiler
barriers on the read-side, and all matching memory barriers on the
write-side are turned into an invocation of a memory barrier on all
active threads in the process. By letting the kernel perform this
synchronization rather than dumbly sending a signal to every process
threads (as we currently do), we diminish the number of unnecessary wake
ups and only issue the memory barriers on active threads. Non-running
threads do not need to execute such barrier anyway, because these are
implied by the scheduler context switches.
Results in liburcu:
Operations in 10s, 6 readers, 2 writers:
memory barriers in reader: 1701557485 reads, 2202847 writes
signal-based scheme: 9830061167 reads, 6700 writes
sys_membarrier: 9952759104 reads, 425 writes
sys_membarrier (dyn. check): 7970328887 reads, 425 writes
The dynamic sys_membarrier availability check adds some overhead to
the read-side compared to the signal-based scheme, but besides that,
sys_membarrier slightly outperforms the signal-based scheme. However,
this non-expedited sys_membarrier implementation has a much slower grace
period than signal and memory barrier schemes.
Besides diminishing the number of wake-ups, one major advantage of the
membarrier system call over the signal-based scheme is that it does not
need to reserve a signal. This plays much more nicely with libraries,
and with processes injected into for tracing purposes, for which we
cannot expect that signals will be unused by the application.
An expedited version of this system call can be added later on to speed
up the grace period. Its implementation will likely depend on reading
the cpu_curr()->mm without holding each CPU's rq lock.
This patch adds the system call to x86 and to asm-generic.
[1] http://urcu.so
membarrier(2) man page:
MEMBARRIER(2) Linux Programmer's Manual MEMBARRIER(2)
NAME
membarrier - issue memory barriers on a set of threads
SYNOPSIS
#include <linux/membarrier.h>
int membarrier(int cmd, int flags);
DESCRIPTION
The cmd argument is one of the following:
MEMBARRIER_CMD_QUERY
Query the set of supported commands. It returns a bitmask of
supported commands.
MEMBARRIER_CMD_SHARED
Execute a memory barrier on all threads running on the system.
Upon return from system call, the caller thread is ensured that
all running threads have passed through a state where all memory
accesses to user-space addresses match program order between
entry to and return from the system call (non-running threads
are de facto in such a state). This covers threads from all pro=E2=80=90
cesses running on the system. This command returns 0.
The flags argument needs to be 0. For future extensions.
All memory accesses performed in program order from each targeted
thread is guaranteed to be ordered with respect to sys_membarrier(). If
we use the semantic "barrier()" to represent a compiler barrier forcing
memory accesses to be performed in program order across the barrier,
and smp_mb() to represent explicit memory barriers forcing full memory
ordering across the barrier, we have the following ordering table for
each pair of barrier(), sys_membarrier() and smp_mb():
The pair ordering is detailed as (O: ordered, X: not ordered):
barrier() smp_mb() sys_membarrier()
barrier() X X O
smp_mb() X O O
sys_membarrier() O O O
RETURN VALUE
On success, these system calls return zero. On error, -1 is returned,
and errno is set appropriately. For a given command, with flags
argument set to 0, this system call is guaranteed to always return the
same value until reboot.
ERRORS
ENOSYS System call is not implemented.
EINVAL Invalid arguments.
Linux 2015-04-15 MEMBARRIER(2)
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Nicholas Miell <nmiell@comcast.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Pranith Kumar <bobby.prani@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the following warning when compiling extract-cert:
scripts/extract-cert.c: In function `write_cert':
scripts/extract-cert.c:89:2: warning: format not a string literal and no format arguments [-Wformat-security]
ERR(!i2d_X509_bio(wb, x509), cert_dst);
^
whereby the ERR() macro is taking cert_dst as the format string. "%s"
should be used as the format string as the path could contain special
characters.
Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: Jim Davis <jim.epost@gmail.com>
Acked-by : David Woodhouse <david.woodhouse@intel.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull watchdog updates from Wim Van Sebroeck:
- new driver for NXP LPC18xx Watchdog Timer
- new driver for SAMA5D4 watchdog timer
- add support for MCP79 to nv_tco driver
- clean-up and improvement of the mpc8xxx watchdog driver
- improvements to gpio-wdt
- at91sam9_wdt clock improvements
... and other small fixes and improvements
* git://www.linux-watchdog.org/linux-watchdog: (25 commits)
Watchdog: Fix parent of watchdog_devices
watchdog: at91rm9200: Correct check for syscon_node_to_regmap() errors
watchdog: at91sam9: get and use slow clock
Documentation: dt: binding: atmel-sama5d4-wdt: for SAMA5D4 watchdog driver
watchdog: add a driver to support SAMA5D4 watchdog timer
watchdog: mpc8xxx: allow to compile for MPC512x
watchdog: mpc8xxx: use better error code when watchdog cannot be enabled
watchdog: mpc8xxx: use dynamic memory for device specific data
watchdog: mpc8xxx: use devm_ioremap_resource to map memory
watchdog: mpc8xxx: make use of of_device_get_match_data
watchdog: mpc8xxx: simplify registration
watchdog: mpc8xxx: remove dead code
watchdog: lpc18xx_wdt_get_timeleft() can be static
DT: watchdog: Add NXP LPC18xx Watchdog Timer binding documentation
watchdog: NXP LPC18xx Watchdog Timer Driver
watchdog: gpio-wdt: ping already at startup for always running devices
watchdog: gpio-wdt: be more strict about hw_algo matching
Documentation: watchdog: at91sam9_wdt: add clocks property
watchdog: booke_wdt: Use infrastructure to check timeout limits
watchdog: (nv_tco) add support for MCP79
...
This reverts commit d353d7587d.
Doing the block layer plug/unplug inside writeback_sb_inodes() is
broken, because that function is actually called with a spinlock held:
wb->list_lock, as pointed out by Chris Mason.
Chris suggested just dropping and re-taking the spinlock around the
blk_finish_plug() call (the plgging itself can happen under the
spinlock), and that would technically work, but is just disgusting.
We do something fairly similar - but not quite as disgusting because we
at least have a better reason for it - in writeback_single_inode(), so
it's not like the caller can depend on the lock being held over the
call, but in this case there just isn't any good reason for that
"release and re-take the lock" pattern.
[ In general, we should really strive to avoid the "release and retake"
pattern for locks, because in the general case it can easily cause
subtle bugs when the caller caches any state around the call that
might be invalidated by dropping the lock even just temporarily. ]
But in this case, the plugging should be easy to just move up to the
callers before the spinlock is taken, which should even improve the
effectiveness of the plug. So there is really no good reason to play
games with locking here.
I'll send off a test-patch so that Dave Chinner can verify that that
plug movement works. In the meantime this just reverts the problematic
commit and adds a comment to the function so that we hopefully don't
make this mistake again.
Reported-by: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull btrfs cleanups and fixes from Chris Mason:
"These are small cleanups, and also some fixes for our async worker
thread initialization.
I was having some trouble testing these, but it ended up being a
combination of changing around my test servers and a shiny new
schedule while atomic from the new start/finish_plug in
writeback_sb_inodes().
That one only hits on btrfs raid5/6 or MD raid10, and if I wasn't
changing a bunch of things in my test setup at once it would have been
really clear. Fix for writeback_sb_inodes() on the way as well"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: cleanup: remove unnecessary check before btrfs_free_path is called
btrfs: async_thread: Fix workqueue 'max_active' value when initializing
btrfs: Add raid56 support for updating num_tolerated_disk_barrier_failures in btrfs_balance
btrfs: Cleanup for btrfs_calc_num_tolerated_disk_barrier_failures
btrfs: Remove noused chunk_tree and chunk_objectid from scrub_enumerate_chunks and scrub_chunk
btrfs: Update out-of-date "skip parity stripe" comment
Thomas Gleixner