- 06 11月, 2013 11 次提交
-
-
由 Vineet Gupta 提交于
Lockdep required a small fix to stacktrace API which was incorrectly unwindign out of __switch_to for the current call frame. Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
In case bootloader has changed the priority of one/more IRQ lines Reported-by: NNoam Camus <noamc@ezchip.com> Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
Emulation not enabled is treated as if the fixup failed, so no need for special #ifdef checks. Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
switch the args (address, pt_regs) to match with all the other "C" exception handlers. This removes the awkwardness in EV_ProtV for page fault vs. unaligned access. Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
Line op needs vaddr (indexing) and paddr (tag match). For page sized flushes (V-P const), each line op will need a different index, but the tag bits wil remain constant, hence paddr can be setup once outside the loop. This improves select LMBench numbers for Aliasing dcache where we have more "preventive" cache flushing. Processor, Processes - times in microseconds - smaller is better ------------------------------------------------------------------------------ Host OS Mhz null null open slct sig sig fork exec sh call I/O stat clos TCP inst hndl proc proc proc --------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- 3.11-rc7- Linux 3.11.0- 80 4.66 8.88 69.7 112. 268. 8.60 28.0 3489 13.K 27.K # Non alias ARC700 3.11-rc7- Linux 3.11.0- 80 4.64 8.51 68.6 98.5 271. 8.58 28.1 4160 15.K 32.K # Aliasing 3.11-rc7- Linux 3.11.0- 80 4.64 8.51 69.8 99.4 270. 8.73 27.5 3880 15.K 31.K # PTAG loop Inv Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
With Line length being constant now, we can fold the 2 helpers into 1. This allows applying any optimizations (forthcoming) to single place. Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
Having them be different seems an obscure configuration. Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
ARC dcache supports 3 ops - Inv, Flush, Flush-n-Inv. The programming model however provides 2 commands FLUSH, INV. INV will either discard or flush-n-discard (based on DT_CTRL bit) The leaf helper __dc_line_loop() used to take the AUX register (corresponding to the 2 commands). Now we push that to within the helper, paving way for code consolidations to follow. Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Vineet Gupta 提交于
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
-
由 Christoph Lameter 提交于
__get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calcualtions are avoided and less registers are used when code is generated. At the end of the patchset all uses of __get_cpu_var have been removed so the macro is removed too. The patchset includes passes over all arches as well. Once these operations are used throughout then specialized macros can be defined in non -x86 arches as well in order to optimize per cpu access by f.e. using a global register that may be set to the per cpu base. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, u); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(this_cpu_ptr(&x), y, sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to this_cpu_inc(y) Acked-by: NVineet Gupta <vgupta@synopsys.com> Signed-off-by: NChristoph Lameter <cl@linux.com>
-
- 04 11月, 2013 3 次提交
-
-
由 Linus Torvalds 提交于
-
git://git.linux-mips.org/pub/scm/ralf/upstream-linus由 Linus Torvalds 提交于
Pull MIPS fixes from Ralf Baechle: "Three fixes across arch/mips with the most complex one being the GIC interrupt fix - at nine lines still not monster. I'm confident this are the final MIPS patches even if there should go for an rc8" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: ralink: fix return value check in rt_timer_probe() MIPS: malta: Fix GIC interrupt offsets MIPS: Perf: Fix 74K cache map
-
由 Mathias Krause 提交于
Negative message lengths make no sense -- so don't do negative queue lenghts or identifier counts. Prevent them from getting negative. Also change the underlying data types to be unsigned to avoid hairy surprises with sign extensions in cases where those variables get evaluated in unsigned expressions with bigger data types, e.g size_t. In case a user still wants to have "unlimited" sizes she could just use INT_MAX instead. Signed-off-by: NMathias Krause <minipli@googlemail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 03 11月, 2013 2 次提交
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux由 Linus Torvalds 提交于
Pull ARM kallsyms fix from Rusty Russell: "Last minute perf unbreakage for ARM modules; spent a day in linux-next" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: scripts/kallsyms: filter symbols not in kernel address space
-
由 Vineet Gupta 提交于
A vmalloc fault needs to sync up PGD/PTE entry from init_mm to current task's "active_mm". ARC vmalloc fault handler however was using mm. A vmalloc fault for non user task context (actually pre-userland, from init thread's open for /dev/console) caused the handler to deref NULL mm (for mm->pgd) The reasons it worked so far is amazing: 1. By default (!SMP), vmalloc fault handler uses a cached value of PGD. In SMP that MMU register is repurposed hence need for mm pointer deref. 2. In pre-3.12 SMP kernel, the problem triggering vmalloc didn't exist in pre-userland code path - it was introduced with commit 20bafb3d "n_tty: Move buffers into n_tty_data" Signed-off-by: NVineet Gupta <vgupta@synopsys.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Noam Camus <noamc@ezchip.com> Cc: stable@vger.kernel.org #3.10 and 3.11 Cc: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 02 11月, 2013 20 次提交
-
-
由 Ming Lei 提交于
This patch uses CONFIG_PAGE_OFFSET to filter symbols which are not in kernel address space because these symbols are generally for generating code purpose and can't be run at kernel mode, so we needn't keep them in /proc/kallsyms. For example, on ARM there are some symbols which may be linked in relocatable code section, then perf can't parse symbols any more from /proc/kallsyms, this patch fixes the problem (introduced b9b32bf7) Cc: Russell King <linux@arm.linux.org.uk> Cc: linux-arm-kernel@lists.infradead.org Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: NMing Lei <tom.leiming@gmail.com> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: stable@vger.kernel.org
-
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip由 Linus Torvalds 提交于
Pull perf fixes from Ingo Molnar: "Two fixes: - Fix 'NMI handler took too long to run' false positives [ Genuine NMI overhead speedups will come for v3.13, this commit only fixes a measurement bug ] - Fix perf ring-buffer missed barrier causing (rare) ring-buffer data corruption on ppc64" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix NMI measurements perf: Fix perf ring buffer memory ordering
-
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb由 Linus Torvalds 提交于
Pull USB fixes from Greg KH: "Here is a set of patches that revert all of the changes done to the pl2303 USB serial driver in the 3.12-rc timeframe, as it turns out they break some devices that work just fine on 3.11. As it's not a good idea to break working systems, drop them all and they will be reworked for future kernel versions such that there is no breakage. I've also included a MAINTAINERS update for the USB serial subsystem and a new device id for the ftdi_sio driver as well" * tag 'usb-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: USB: serial: ftdi_sio: add id for Z3X Box device USB: Maintainers change for usb serial drivers Revert "USB: pl2303: restrict the divisor based baud rate encoding method to the "HX" chip type" Revert "usb: pl2303: fix+improve the divsor based baud rate encoding method" Revert "usb: pl2303: do not round to the next nearest standard baud rate for the divisor based baud rate encoding method" Revert "usb: pl2303: remove 500000 baud from the list of standard baud rates" Revert "usb: pl2303: move the two baud rate encoding methods to separate functions" Revert "usb: pl2303: increase the allowed baud rate range for the divisor based encoding method" Revert "usb: pl2303: also use the divisor based baud rate encoding method for baud rates < 115200 with HX chips" Revert "usb: pl2303: add two comments concerning the supported baud rates with HX chips" Revert "pl2303: simplify the else-if contruct for type_1 chips in pl2303_startup()" Revert "pl2303: improve the chip type information output on startup" Revert "pl2303: improve the chip type detection/distinction" Revert "USB: pl2303: distinguish between original and cloned HX chips"
-
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound由 Linus Torvalds 提交于
Pull more sound fixes from Takashi Iwai: "The fixes for random bugs that have been reported lately in the game: a few fixes in ASoC dpam and wm_hubs bugs spotted by Coverity, a one-liner HD-audio fixup, and a fix for Oops with DPCM. They are not so critically urgent bugs, but all small and safe" * tag 'sound-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: fix oops in snd_pcm_info() caused by ASoC DPCM ASoC: wm_hubs: Add missing break in hp_supply_event() ALSA: hda - Add a fixup for ASUS N76VZ ASoC: dapm: Return -ENOMEM in snd_soc_dapm_new_dai_widgets() ASoC: dapm: Fix source list debugfs outputs
-
git://git.linaro.org/people/mturquette/linux由 Linus Torvalds 提交于
Pull clock subsystem fixes from Mike Turquette. * tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mturquette/linux: clk: fixup argument order when setting VCO parameters clk: socfpga: Fix incorrect sdmmc clock name clk: armada-370: fix tclk frequencies clk: nomadik: set all timers to use 2.4 MHz TIMCLK
-
由 Greg Thelen 提交于
When a memcg is deleted mem_cgroup_reparent_charges() moves charged memory to the parent memcg. As of v3.11-9444-g3ea67d06 "memcg: add per cgroup writeback pages accounting" there's bad pointer read. The goal was to check for counter underflow. The counter is a per cpu counter and there are two problems with the code: (1) per cpu access function isn't used, instead a naked pointer is used which easily causes oops. (2) the check doesn't sum all cpus Test: $ cd /sys/fs/cgroup/memory $ mkdir x $ echo 3 > /proc/sys/vm/drop_caches $ (echo $BASHPID >> x/tasks && exec cat) & [1] 7154 $ grep ^mapped x/memory.stat mapped_file 53248 $ echo 7154 > tasks $ rmdir x <OOPS> The fix is to remove the check. It's currently dangerous and isn't worth fixing it to use something expensive, such as percpu_counter_sum(), for each reparented page. __this_cpu_read() isn't enough to fix this because there's no guarantees of the current cpus count. The only guarantees is that the sum of all per-cpu counter is >= nr_pages. Fixes: 3ea67d06 ("memcg: add per cgroup writeback pages accounting") Reported-and-tested-by: NFlavio Leitner <fbl@redhat.com> Signed-off-by: NGreg Thelen <gthelen@google.com> Reviewed-by: NSha Zhengju <handai.szj@taobao.com> Acked-by: NJohannes Weiner <hannes@cmpxchg.org> Signed-off-by: NHugh Dickins <hughd@google.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Алексей Крамаренко 提交于
Custom VID/PID for Z3X Box device, popular tool for cellphone flashing. Signed-off-by: NAlexey E. Kramarenko <alexeyk13@yandex.ru> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg KH 提交于
Johan has been conned^Wgracious in accepting the maintainership of the USB serial drivers, especially as he's been doing all of the real work for the past few years. At the same time, remove a bunch of old entries for USB serial drivers that don't make sense anymore, given that the developers are no longer around, and individual driver maintainerships for tiny things like this is pretty pointless. Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit b8bdad60. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit 57ce61aa. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
Revert "usb: pl2303: do not round to the next nearest standard baud rate for the divisor based baud rate encoding method" This reverts commit 75417d9f. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit b9208c72. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit e917ba01. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit b5c16c6a. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
Revert "usb: pl2303: also use the divisor based baud rate encoding method for baud rates < 115200 with HX chips" This reverts commit 61fa8d69. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit c23bda36. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit 73b583af. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit a77a8c23. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit 034d1527. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
由 Greg Kroah-Hartman 提交于
This reverts commit 7d26a78f. Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as they cause regressions on some versions of the chip. This will all be revisited for later kernel versions when we can figure out how to handle this in a way that does not break working devices. Reported-by: NMika Westerberg <mika.westerberg@linux.intel.com> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by: NJohan Hovold <jhovold@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
-
- 01 11月, 2013 4 次提交
-
-
由 Linus Torvalds 提交于
Merge four more fixes from Andrew Morton. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: lib/scatterlist.c: don't flush_kernel_dcache_page on slab page mm: memcg: fix test for child groups mm: memcg: lockdep annotation for memcg OOM lock mm: memcg: use proper memcg in limit bypass
-
由 Ming Lei 提交于
Commit b1adaf65 ("[SCSI] block: add sg buffer copy helper functions") introduces two sg buffer copy helpers, and calls flush_kernel_dcache_page() on pages in SG list after these pages are written to. Unfortunately, the commit may introduce a potential bug: - Before sending some SCSI commands, kmalloc() buffer may be passed to block layper, so flush_kernel_dcache_page() can see a slab page finally - According to cachetlb.txt, flush_kernel_dcache_page() is only called on "a user page", which surely can't be a slab page. - ARCH's implementation of flush_kernel_dcache_page() may use page mapping information to do optimization so page_mapping() will see the slab page, then VM_BUG_ON() is triggered. Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled, and this patch fixes the bug by adding test of '!PageSlab(miter->page)' before calling flush_kernel_dcache_page(). Signed-off-by: NMing Lei <ming.lei@canonical.com> Reported-by: NAaro Koskinen <aaro.koskinen@iki.fi> Tested-by: NSimon Baatz <gmbnomis@gmail.com> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: NCatalin Marinas <catalin.marinas@arm.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Tejun Heo <tj@kernel.org> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> [3.2+] Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Johannes Weiner 提交于
When memcg code needs to know whether any given memcg has children, it uses the cgroup child iteration primitives and returns true/false depending on whether the iteration loop is executed at least once or not. Because a cgroup's list of children is RCU protected, these primitives require the RCU read-lock to be held, which is not the case for all memcg callers. This results in the following splat when e.g. enabling hierarchy mode: WARNING: CPU: 3 PID: 1 at kernel/cgroup.c:3043 css_next_child+0xa3/0x160() CPU: 3 PID: 1 Comm: systemd Not tainted 3.12.0-rc5-00117-g83f11a9c-dirty #18 Hardware name: LENOVO 3680B56/3680B56, BIOS 6QET69WW (1.39 ) 04/26/2012 Call Trace: dump_stack+0x54/0x74 warn_slowpath_common+0x78/0xa0 warn_slowpath_null+0x1a/0x20 css_next_child+0xa3/0x160 mem_cgroup_hierarchy_write+0x5b/0xa0 cgroup_file_write+0x108/0x2a0 vfs_write+0xbd/0x1e0 SyS_write+0x4c/0xa0 system_call_fastpath+0x16/0x1b In the memcg case, we only care about children when we are attempting to modify inheritable attributes interactively. Racing with deletion could mean a spurious -EBUSY, no problem. Racing with addition is handled just fine as well through the memcg_create_mutex: if the child group is not on the list after the mutex is acquired, it won't be initialized from the parent's attributes until after the unlock. Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org> Acked-by: NMichal Hocko <mhocko@suse.cz> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Johannes Weiner 提交于
The memcg OOM lock is a mutex-type lock that is open-coded due to memcg's special needs. Add annotations for lockdep coverage. Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-