- 28 10月, 2010 8 次提交
-
-
由 Michael Hennerich 提交于
Some ADP5588 functions take a pointer to an i2c_client, but if the i2c header doesn't happen to be included first, we hit the standard "struct declared inside parameter list" warnings from gcc. So add a simple forward decl of the i2c_client struct. Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com> Signed-off-by: NMike Frysinger <vapier@gentoo.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michael Hennerich 提交于
Common code interprets this as a signed value (a negative value is used to request dynamic ID allocation), so make sure the platform data has proper types to support that. Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com> Signed-off-by: NMike Frysinger <vapier@gentoo.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michael Hennerich 提交于
Implement irq_chip functionality on ADP5588/5587 GPIO expanders. Only level sensitive interrupts are supported. Interrupts provided by this irq_chip must be requested using request_threaded_irq(). Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com> Signed-off-by: NMike Frysinger <vapier@gentoo.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Miguel Gaio 提交于
Add support for generic 74x164 serial-in/parallel-out 8-bits shift register. This driver can be used as a GPIO output expander. [akpm@linux-foundation.org: remove unused local `refresh'] Signed-off-by: NMiguel Gaio <miguel.gaio@efixo.com> Signed-off-by: NJuhos Gabor <juhosg@openwrt.org> Signed-off-by: NFlorian Fainelli <florian@openwrt.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Anton Vorontsov 提交于
commit 7444a72e ("gpiolib: allow user-selection") removed HAVE_GPIO_LIB Kconfig symbol, but the header file still uses the name [to confuse readers wrt #ifdef/#else/#endif location]. The real Kconfig symbol nowadays is CONFIG_GPIOLIB. Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Anton Vorontsov 提交于
The basic GPIO controllers may be found in various on-board FPGA and ASIC solutions that are used to control board's switches, LEDs, chip-selects, Ethernet/USB PHY power, etc. These controllers may not provide any means of pin setup (in/out/open drain). The driver supports: - 8/16/32/64 bits registers; - GPIO controllers with clear/set registers; - GPIO controllers with a single "data" register; - Big endian bits/GPIOs ordering (mostly used on PowerPC). Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com> Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com> Cc: David Brownell <david-b@pacbell.net> Cc: Samuel Ortiz <sameo@linux.intel.com>, Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Peter Zijlstra 提交于
Christoph reported a nice splat which illustrated a race in the new stack based kmap_atomic implementation. The problem is that we pop our stack slot before we're completely done resetting its state -- in particular clearing the PTE (sometimes that's CONFIG_DEBUG_HIGHMEM). If an interrupt happens before we actually clear the PTE used for the last slot, that interrupt can reuse the slot in a dirty state, which triggers a BUG in kmap_atomic(). Fix this by introducing kmap_atomic_idx() which reports the current slot index without actually releasing it and use that to find the PTE and delay the _pop() until after we're completely done. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: NChristoph Hellwig <hch@infradead.org> Acked-by: NRik van Riel <riel@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Peter Zijlstra 提交于
It appears i386 uses kmap_atomic infrastructure regardless of CONFIG_HIGHMEM which results in a compile error when highmem is disabled. Cure this by providing the needed few bits for both CONFIG_HIGHMEM and CONFIG_X86_32. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: NChris Wilson <chris@chris-wilson.co.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 27 10月, 2010 32 次提交
-
-
由 Randy Dunlap 提交于
Add idr/ida to kernel-api docbook. Fix typos and kernel-doc notation. Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com> Acked-by: NTejun Heo <tj@kernel.org> Cc: Naohiro Aota <naota@elisp.net> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Randy Dunlap 提交于
Add more wait, wake, and completion interfaces to the device-drivers docbook. Fix kernel-doc notation in the added files. Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Brian Behlendorf 提交于
The current implementation of div64_u64 for 32bit systems returns an approximately correct result when the divisor exceeds 32bits. Since doing 64bit division using 32bit hardware is a long since solved problem we just use one of the existing proven methods. Additionally, add a div64_s64 function to correctly handle doing signed 64bit division. Addresses https://bugzilla.redhat.com/show_bug.cgi?id=616105Signed-off-by: NBrian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: NOleg Nesterov <oleg@redhat.com> Cc: Ben Woodard <bwoodard@llnl.gov> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Mark Grondona <mgrondona@llnl.gov> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Andrew Morton 提交于
printk_ratelimit() was a bad idea - we don't want subsytem A causing ratelimiting of subsystem B's messages. Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Namhyung Kim 提交于
Adding declaration of printk_ratelimit_state in ratelimit.h removes potential build breakage and following sparse warning: kernel/printk.c:1426:1: warning: symbol 'printk_ratelimit_state' was not declared. Should it be static? [akpm@linux-foundation.org: remove unneeded ifdef] Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Peter Zijlstra 提交于
PF_FLUSHER is only ever set, not tested, remove it. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Eric Dumazet 提交于
Robin Holt tried to boot a 16TB system and found af_unix was overflowing a 32bit value : <quote> We were seeing a failure which prevented boot. The kernel was incapable of creating either a named pipe or unix domain socket. This comes down to a common kernel function called unix_create1() which does: atomic_inc(&unix_nr_socks); if (atomic_read(&unix_nr_socks) > 2 * get_max_files()) goto out; The function get_max_files() is a simple return of files_stat.max_files. files_stat.max_files is a signed integer and is computed in fs/file_table.c's files_init(). n = (mempages * (PAGE_SIZE / 1024)) / 10; files_stat.max_files = n; In our case, mempages (total_ram_pages) is approx 3,758,096,384 (0xe0000000). That leaves max_files at approximately 1,503,238,553. This causes 2 * get_max_files() to integer overflow. </quote> Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long integers, and change af_unix to use an atomic_long_t instead of atomic_t. get_max_files() is changed to return an unsigned long. get_nr_files() is changed to return a long. unix_nr_socks is changed from atomic_t to atomic_long_t, while not strictly needed to address Robin problem. Before patch (on a 64bit kernel) : # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max -18446744071562067968 After patch: # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max 2147483648 # cat /proc/sys/fs/file-nr 704 0 2147483648 Reported-by: NRobin Holt <holt@sgi.com> Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Acked-by: NDavid Miller <davem@davemloft.net> Reviewed-by: NRobin Holt <holt@sgi.com> Tested-by: NRobin Holt <holt@sgi.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org> -
由 Samu Onkalo 提交于
This is a driver for Avago APDS990X combined ALS and proximity sensor. Interface is sysfs based. The driver uses interrupts to provide new data. The driver supports pm_runtime and regulator frameworks. See Documentation/misc-devices/apds990x.txt for details Signed-off-by: NSamu Onkalo <samu.p.onkalo@nokia.com> Acked-by: NJonathan Cameron <jic23@cam.ac.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Samu Onkalo 提交于
This is a driver for ROHM BH1770GLC and OSRAM SFH7770 combined ALS and proximity sensor. Interface is sysfs based. The driver uses interrupts to provide new data. The driver supports pm_runtime and regulator frameworks. See Documentation/misc-devices/bh1770glc.txt for details Signed-off-by: NSamu Onkalo <samu.p.onkalo@nokia.com> Acked-by: NJonathan Cameron <jic23@cam.ac.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Andrew Morton 提交于
Silly though it is, completions and wait_queue_heads use foo_ONSTACK (COMPLETION_INITIALIZER_ONSTACK, DECLARE_COMPLETION_ONSTACK, __WAIT_QUEUE_HEAD_INIT_ONSTACK and DECLARE_WAIT_QUEUE_HEAD_ONSTACK) so I guess workqueues should do the same thing. s/INIT_WORK_ON_STACK/INIT_WORK_ONSTACK/ s/INIT_DELAYED_WORK_ON_STACK/INIT_DELAYED_WORK_ONSTACK/ Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NTejun Heo <tj@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Mike Frysinger 提交于
The new init ramfs format (cpio based) requires an alignment of 4 (per the documentation and per the source files themselves). As for compressed sources, the decompressors can all deal with unaligned buffers. The cpio source is also found in the __init sections of the kernel, so once they are read and expanded into a tmpfs, the source is freed. That means there is no need to force page alignment here either. This has been used on Blackfin systems for many releases without issue. Signed-off-by: NMike Frysinger <vapier@gentoo.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Mike Frysinger 提交于
With the recent change "net: remove time limit in process_backlog()", the softnet_data variable changed from "DEFINE_PER_CPU()" to "DEFINE_PER_CPU_ALIGNED()" which moved it from the .data section to the .data.shared_align section. I'm not saying this patch is wrong, just that is what caused me to notice this larger problem. No one else in the kernel is using this aligned macro variant, so I imagine that's why no one has noticed yet. Since .data..shared_align isn't declared in any vmlinux files that I can see, the linker just places it last. This "just works" for most people, but when building a ROM kernel on Blackfin systems, it causes section overlap errors: bfin-uclinux-ld.real: section .init.data [00000000202e06b8 -> 00000000202e48b7] overlaps section .data.shared_aligned [00000000202e06b8 -> 00000000202e0723] I imagine other arches which support the ROM config option and thus do funky placement would see similar issues ... On x86, it is stuck in a dedicated section at the end: [8] .data PROGBITS ffffffff810ec000 2ec0000303a8 00 WA 0 0 4096 [9] .data.shared_alig PROGBITS ffffffff8111c3c0 31c3c00000c8 00 WA 0 0 64 So make sure we include this section in the DATA_DATA macro so that it is placed in the right location. Signed-off-by: NMike Frysinger <vapier@gentoo.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Cc: Greg Ungerer <gerg@snapgear.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Jan Beulich 提交于
gcc aligns strings as a performance consideration for those cases where strings are being used a lot. Their use is not performance critical, and hence it seems better to save some space. Signed-off-by: NJan Beulich <jbeulich@novell.com> Acked-by: NRusty Russell <rusty@rustcorp.com.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Andrew Morton 提交于
The whole point to using the strict functions is to check the return value. If you don't, strict_strto*() will return you uninitialised garbage. Offenders have been observed in the wild. Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Hagen Paul Pfeifer 提交于
Introduce two additional min/max macros to compare three operands. This will save some cycles as well as some bytes on the stack and last but not least more pleasing as macro nesting. [akpm@linux-foundation.org: fix warnings] Signed-off-by: NHagen Paul Pfeifer <hagen@jauu.net> Cc: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Hartley Sweeten <hsweeten@visionengravers.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Roland Dreier <rolandd@cisco.com> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Dave Young 提交于
Add vzalloc() and vzalloc_node() to encapsulate the vmalloc-then-memset-zero operation. Use __GFP_ZERO to zero fill the allocated memory. Signed-off-by: NDave Young <hidave.darkstar@gmail.com> Cc: Christoph Lameter <cl@linux-foundation.org> Acked-by: NGreg Ungerer <gerg@snapgear.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Namhyung Kim 提交于
Introduce ___GFP_* masks in order for gfp_t to not be mixed with plain integers which causes a lot of warnings like the following: warning: restricted gfp_t degrades to integer Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Namhyung Kim 提交于
Declare 'bdi_pending_list' and 'tag_pages_for_writeback()' to remove following sparse warnings: mm/backing-dev.c:46:1: warning: symbol 'bdi_pending_list' was not declared. Should it be static? mm/page-writeback.c:825:6: warning: symbol 'tag_pages_for_writeback' was not declared. Should it be static? Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Namhyung Kim 提交于
The page_check_address() conditionally grabs *@ptlp in case of returning non-NULL. Rename and wrap it using __cond_lock() removes following warnings from sparse: mm/rmap.c:472:9: warning: context imbalance in 'page_mapped_in_vma' - unexpected unlock mm/rmap.c:524:9: warning: context imbalance in 'page_referenced_one' - unexpected unlock mm/rmap.c:706:9: warning: context imbalance in 'page_mkclean_one' - unexpected unlock mm/rmap.c:1066:9: warning: context imbalance in 'try_to_unmap_one' - unexpected unlock Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Namhyung Kim 提交于
The page_lock_anon_vma() conditionally grabs RCU and anon_vma lock but page_unlock_anon_vma() releases them unconditionally. This leads sparse to complain about context imbalance. Annotate them. Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Namhyung Kim 提交于
The get_locked_pte() conditionally grabs 'ptl' in case of returning non-NULL. This leads sparse to complain about context imbalance. Rename and wrap it using __cond_lock() to make sparse happy. Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michel Lespinasse 提交于
This change reduces mmap_sem hold times that are caused by waiting for disk transfers when accessing file mapped VMAs. It introduces the VM_FAULT_ALLOW_RETRY flag, which indicates that the call site wants mmap_sem to be released if blocking on a pending disk transfer. In that case, filemap_fault() returns the VM_FAULT_RETRY status bit and do_page_fault() will then re-acquire mmap_sem and retry the page fault. It is expected that the retry will hit the same page which will now be cached, and thus it will complete with a low mmap_sem hold time. Tests: - microbenchmark: thread A mmaps a large file and does random read accesses to the mmaped area - achieves about 55 iterations/s. Thread B does mmap/munmap in a loop at a separate location - achieves 55 iterations/s before, 15000 iterations/s after. - We are seeing related effects in some applications in house, which show significant performance regressions when running without this change. [akpm@linux-foundation.org: fix warning & crash] Signed-off-by: NMichel Lespinasse <walken@google.com> Acked-by: NRik van Riel <riel@redhat.com> Acked-by: NLinus Torvalds <torvalds@linux-foundation.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Reviewed-by: NWu Fengguang <fengguang.wu@intel.com> Cc: Ying Han <yinghan@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: N"H. Peter Anvin" <hpa@zytor.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Richard Kennedy 提交于
Reorder structure anon_vma to remove alignment padding on 64 builds when (CONFIG_KSM || CONFIG_MIGRATION). This will shrink the size of the anon_vma structure from 40 to 32 bytes & allow more objects per slab in its kmem_cache. Under slub the objects in the anon_vma kmem_cache will then be 40 bytes with 102 objects per slab. (On v2.6.36 without this patch,the size is 48 bytes and 85 objects/slab.) Signed-off-by: NRichard Kennedy <richard@rsk.demon.co.uk> Reviewed-by: NRik van Riel <riel@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Peter Zijlstra 提交于
Keep the current interface but ignore the KM_type and use a stack based approach. The advantage is that we get rid of crappy code like: #define __KM_PTE \ (in_nmi() ? KM_NMI_PTE : \ in_irq() ? KM_IRQ_PTE : \ KM_PTE0) and in general can stop worrying about what context we're in and what kmap slots might be appropriate for that. The downside is that FRV kmap_atomic() gets more expensive. For now we use a CPP trick suggested by Andrew: #define kmap_atomic(page, args...) __kmap_atomic(page) to avoid having to touch all kmap_atomic() users in a single patch. [ not compiled on: - mn10300: the arch doesn't actually build with highmem to begin with ] [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c] Acked-by: NRik van Riel <riel@redhat.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NChris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Miller <davem@davemloft.net> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Airlie <airlied@linux.ie> Cc: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Peter Zijlstra 提交于
Ensure kmap_atomic() usage is strictly nested Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: NRik van Riel <riel@redhat.com> Acked-by: NChris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Miller <davem@davemloft.net> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Mel Gorman 提交于
writeback: do not sleep on the congestion queue if there are no congested BDIs or if significant congestion is not being encountered in the current zone If congestion_wait() is called with no BDI congested, the caller will sleep for the full timeout and this may be an unnecessary sleep. This patch adds a wait_iff_congested() that checks congestion and only sleeps if a BDI is congested else, it calls cond_resched() to ensure the caller is not hogging the CPU longer than its quota but otherwise will not sleep. This is aimed at reducing some of the major desktop stalls reported during IO. For example, while kswapd is operating, it calls congestion_wait() but it could just have been reclaiming clean page cache pages with no congestion. Without this patch, it would sleep for a full timeout but after this patch, it'll just call schedule() if it has been on the CPU too long. Similar logic applies to direct reclaimers that are not making enough progress. Signed-off-by: NMel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 KOSAKI Motohiro 提交于
shrink_page_list() can decide to give up reclaiming a page under a number of conditions such as 1. trylock_page() failure 2. page is unevictable 3. zone reclaim and page is mapped 4. PageWriteback() is true 5. page is swapbacked and swap is full 6. add_to_swap() failure 7. page is dirty and gfpmask don't have GFP_IO, GFP_FS 8. page is pinned 9. IO queue is congested 10. pageout() start IO, but not finished With lumpy reclaim, failures result in entering synchronous lumpy reclaim but this can be unnecessary. In cases (2), (3), (5), (6), (7) and (8), there is no point retrying. This patch causes lumpy reclaim to abort when it is known it will fail. Case (9) is more interesting. current behavior is, 1. start shrink_page_list(async) 2. found queue_congested() 3. skip pageout write 4. still start shrink_page_list(sync) 5. wait on a lot of pages 6. again, found queue_congested() 7. give up pageout write again So, it's useless time wasting. However, just skipping page reclaim is also notgood as x86 allocating a huge page needs 512 pages for example. It can have more dirty pages than queue congestion threshold (~=128). After this patch, pageout() behaves as follows; - If order > PAGE_ALLOC_COSTLY_ORDER Ignore queue congestion always. - If order <= PAGE_ALLOC_COSTLY_ORDER skip write page and disable lumpy reclaim. Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NMel Gorman <mel@csn.ul.ie> Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Mel Gorman 提交于
There is strong evidence to indicate a lot of time is being spent in congestion_wait(), some of it unnecessarily. This patch adds a tracepoint for congestion_wait to record when congestion_wait() was called, how long the timeout was for and how long it actually slept. Signed-off-by: NMel Gorman <mel@csn.ul.ie> Reviewed-by: NMinchan Kim <minchan.kim@gmail.com> Reviewed-by: NJohannes Weiner <hannes@cmpxchg.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Mel Gorman 提交于
There have been numerous reports of stalls that pointed at the problem being somewhere in the VM. There are multiple roots to the problems which means dealing with any of the root problems in isolation is tricky to justify on their own and they would still need integration testing. This patch series puts together two different patch sets which in combination should tackle some of the root causes of latency problems being reported. Patch 1 adds a tracepoint for shrink_inactive_list. For this series, the most important results is being able to calculate the scanning/reclaim ratio as a measure of the amount of work being done by page reclaim. Patch 2 accounts for time spent in congestion_wait. Patches 3-6 were originally developed by Kosaki Motohiro but reworked for this series. It has been noted that lumpy reclaim is far too aggressive and trashes the system somewhat. As SLUB uses high-order allocations, a large cost incurred by lumpy reclaim will be noticeable. It was also reported during transparent hugepage support testing that lumpy reclaim was trashing the system and these patches should mitigate that problem without disabling lumpy reclaim. Patch 7 adds wait_iff_congested() and replaces some callers of congestion_wait(). wait_iff_congested() only sleeps if there is a BDI that is currently congested. Patch 8 notes that any BDI being congested is not necessarily a problem because there could be multiple BDIs of varying speeds and numberous zones. It attempts to track when a zone being reclaimed contains many pages backed by a congested BDI and if so, reclaimers wait on the congestion queue. I ran a number of tests with monitoring on X86, X86-64 and PPC64. Each machine had 3G of RAM and the CPUs were X86: Intel P4 2-core X86-64: AMD Phenom 4-core PPC64: PPC970MP Each used a single disk and the onboard IO controller. Dirty ratio was left at 20. I'm just going to report for X86-64 and PPC64 in a vague attempt to keep this report short. Four kernels were tested each based on v2.6.36-rc4 traceonly-v2r2: Patches 1 and 2 to instrument vmscan reclaims and congestion_wait lowlumpy-v2r3: Patches 1-6 to test if lumpy reclaim is better waitcongest-v2r3: Patches 1-7 to only wait on congestion waitwriteback-v2r4: Patches 1-8 to detect when a zone is congested nocongest-v1r5: Patches 1-3 for testing wait_iff_congestion nodirect-v1r5: Patches 1-10 to disable filesystem writeback for better IO The tests run were as follows kernbench compile-based benchmark. Smoke test performance sysbench OLTP read-only benchmark. Will be re-run in the future as read-write micro-mapped-file-stream This is a micro-benchmark from Johannes Weiner that accesses a large sparse-file through mmap(). It was configured to run in only single-CPU mode but can be indicative of how well page reclaim identifies suitable pages. stress-highalloc Tries to allocate huge pages under heavy load. kernbench, iozone and sysbench did not report any performance regression on any machine. sysbench did pressure the system lightly and there was reclaim activity but there were no difference of major interest between the kernels. X86-64 micro-mapped-file-stream traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4 pgalloc_dma 1639.00 ( 0.00%) 667.00 (-145.73%) 1167.00 ( -40.45%) 578.00 (-183.56%) pgalloc_dma32 2842410.00 ( 0.00%) 2842626.00 ( 0.01%) 2843043.00 ( 0.02%) 2843014.00 ( 0.02%) pgalloc_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgsteal_dma 729.00 ( 0.00%) 85.00 (-757.65%) 609.00 ( -19.70%) 125.00 (-483.20%) pgsteal_dma32 2338721.00 ( 0.00%) 2447354.00 ( 4.44%) 2429536.00 ( 3.74%) 2436772.00 ( 4.02%) pgsteal_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_kswapd_dma 1469.00 ( 0.00%) 532.00 (-176.13%) 1078.00 ( -36.27%) 220.00 (-567.73%) pgscan_kswapd_dma32 4597713.00 ( 0.00%) 4503597.00 ( -2.09%) 4295673.00 ( -7.03%) 3891686.00 ( -18.14%) pgscan_kswapd_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_direct_dma 71.00 ( 0.00%) 134.00 ( 47.01%) 243.00 ( 70.78%) 352.00 ( 79.83%) pgscan_direct_dma32 305820.00 ( 0.00%) 280204.00 ( -9.14%) 600518.00 ( 49.07%) 957485.00 ( 68.06%) pgscan_direct_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pageoutrun 16296.00 ( 0.00%) 21254.00 ( 23.33%) 18447.00 ( 11.66%) 20067.00 ( 18.79%) allocstall 443.00 ( 0.00%) 273.00 ( -62.27%) 513.00 ( 13.65%) 1568.00 ( 71.75%) These are based on the raw figures taken from /proc/vmstat. It's a rough measure of reclaim activity. Note that allocstall counts are higher because we are entering direct reclaim more often as a result of not sleeping in congestion. In itself, it's not necessarily a bad thing. It's easier to get a view of what happened from the vmscan tracepoint report. FTrace Reclaim Statistics: vmscan traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4 Direct reclaims 443 273 513 1568 Direct reclaim pages scanned 305968 280402 600825 957933 Direct reclaim pages reclaimed 43503 19005 30327 117191 Direct reclaim write file async I/O 0 0 0 0 Direct reclaim write anon async I/O 0 3 4 12 Direct reclaim write file sync I/O 0 0 0 0 Direct reclaim write anon sync I/O 0 0 0 0 Wake kswapd requests 187649 132338 191695 267701 Kswapd wakeups 3 1 4 1 Kswapd pages scanned 4599269 4454162 4296815 3891906 Kswapd pages reclaimed 2295947 2428434 2399818 2319706 Kswapd reclaim write file async I/O 1 0 1 1 Kswapd reclaim write anon async I/O 59 187 41 222 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 4.34 2.52 6.63 2.96 Time kswapd awake (seconds) 11.15 10.25 11.01 10.19 Total pages scanned 4905237 4734564 4897640 4849839 Total pages reclaimed 2339450 2447439 2430145 2436897 %age total pages scanned/reclaimed 47.69% 51.69% 49.62% 50.25% %age total pages scanned/written 0.00% 0.00% 0.00% 0.00% %age file pages scanned/written 0.00% 0.00% 0.00% 0.00% Percentage Time Spent Direct Reclaim 29.23% 19.02% 38.48% 20.25% Percentage Time kswapd Awake 78.58% 78.85% 76.83% 79.86% What is interesting here for nocongest in particular is that while direct reclaim scans more pages, the overall number of pages scanned remains the same and the ratio of pages scanned to pages reclaimed is more or less the same. In other words, while we are sleeping less, reclaim is not doing more work and as direct reclaim and kswapd is awake for less time, it would appear to be doing less work. FTrace Reclaim Statistics: congestion_wait Direct number congest waited 87 196 64 0 Direct time congest waited 4604ms 4732ms 5420ms 0ms Direct full congest waited 72 145 53 0 Direct number conditional waited 0 0 324 1315 Direct time conditional waited 0ms 0ms 0ms 0ms Direct full conditional waited 0 0 0 0 KSwapd number congest waited 20 10 15 7 KSwapd time congest waited 1264ms 536ms 884ms 284ms KSwapd full congest waited 10 4 6 2 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 The vanilla kernel spent 8 seconds asleep in direct reclaim and no time at all asleep with the patches. MMTests Statistics: duration User/Sys Time Running Test (seconds) 10.51 10.73 10.6 11.66 Total Elapsed Time (seconds) 14.19 13.00 14.33 12.76 Overall, the tests completed faster. It is interesting to note that backing off further when a zone is congested and not just a BDI was more efficient overall. PPC64 micro-mapped-file-stream pgalloc_dma 3024660.00 ( 0.00%) 3027185.00 ( 0.08%) 3025845.00 ( 0.04%) 3026281.00 ( 0.05%) pgalloc_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgsteal_dma 2508073.00 ( 0.00%) 2565351.00 ( 2.23%) 2463577.00 ( -1.81%) 2532263.00 ( 0.96%) pgsteal_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_kswapd_dma 4601307.00 ( 0.00%) 4128076.00 ( -11.46%) 3912317.00 ( -17.61%) 3377165.00 ( -36.25%) pgscan_kswapd_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_direct_dma 629825.00 ( 0.00%) 971622.00 ( 35.18%) 1063938.00 ( 40.80%) 1711935.00 ( 63.21%) pgscan_direct_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pageoutrun 27776.00 ( 0.00%) 20458.00 ( -35.77%) 18763.00 ( -48.04%) 18157.00 ( -52.98%) allocstall 977.00 ( 0.00%) 2751.00 ( 64.49%) 2098.00 ( 53.43%) 5136.00 ( 80.98%) Similar trends to x86-64. allocstalls are up but it's not necessarily bad. FTrace Reclaim Statistics: vmscan Direct reclaims 977 2709 2098 5136 Direct reclaim pages scanned 629825 963814 1063938 1711935 Direct reclaim pages reclaimed 75550 242538 150904 387647 Direct reclaim write file async I/O 0 0 0 2 Direct reclaim write anon async I/O 0 10 0 4 Direct reclaim write file sync I/O 0 0 0 0 Direct reclaim write anon sync I/O 0 0 0 0 Wake kswapd requests 392119 1201712 571935 571921 Kswapd wakeups 3 2 3 3 Kswapd pages scanned 4601307 4128076 3912317 3377165 Kswapd pages reclaimed 2432523 2318797 2312673 2144616 Kswapd reclaim write file async I/O 20 1 1 1 Kswapd reclaim write anon async I/O 57 132 11 121 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 6.19 7.30 13.04 10.88 Time kswapd awake (seconds) 21.73 26.51 25.55 23.90 Total pages scanned 5231132 5091890 4976255 5089100 Total pages reclaimed 2508073 2561335 2463577 2532263 %age total pages scanned/reclaimed 47.95% 50.30% 49.51% 49.76% %age total pages scanned/written 0.00% 0.00% 0.00% 0.00% %age file pages scanned/written 0.00% 0.00% 0.00% 0.00% Percentage Time Spent Direct Reclaim 18.89% 20.65% 32.65% 27.65% Percentage Time kswapd Awake 72.39% 80.68% 78.21% 77.40% Again, a similar trend that the congestion_wait changes mean that direct reclaim scans more pages but the overall number of pages scanned while slightly reduced, are very similar. The ratio of scanning/reclaimed remains roughly similar. The downside is that kswapd and direct reclaim was awake longer and for a larger percentage of the overall workload. It's possible there were big differences in the amount of time spent reclaiming slab pages between the different kernels which is plausible considering that the micro tests runs after fsmark and sysbench. Trace Reclaim Statistics: congestion_wait Direct number congest waited 845 1312 104 0 Direct time congest waited 19416ms 26560ms 7544ms 0ms Direct full congest waited 745 1105 72 0 Direct number conditional waited 0 0 1322 2935 Direct time conditional waited 0ms 0ms 12ms 312ms Direct full conditional waited 0 0 0 3 KSwapd number congest waited 39 102 75 63 KSwapd time congest waited 2484ms 6760ms 5756ms 3716ms KSwapd full congest waited 20 48 46 25 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 The vanilla kernel spent 20 seconds asleep in direct reclaim and only 312ms asleep with the patches. The time kswapd spent congest waited was also reduced by a large factor. MMTests Statistics: duration ser/Sys Time Running Test (seconds) 26.58 28.05 26.9 28.47 Total Elapsed Time (seconds) 30.02 32.86 32.67 30.88 With all patches applies, the completion times are very similar. X86-64 STRESS-HIGHALLOC traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Pass 1 82.00 ( 0.00%) 84.00 ( 2.00%) 85.00 ( 3.00%) 85.00 ( 3.00%) Pass 2 90.00 ( 0.00%) 87.00 (-3.00%) 88.00 (-2.00%) 89.00 (-1.00%) At Rest 92.00 ( 0.00%) 90.00 (-2.00%) 90.00 (-2.00%) 91.00 (-1.00%) Success figures across the board are broadly similar. traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Direct reclaims 1045 944 886 887 Direct reclaim pages scanned 135091 119604 109382 101019 Direct reclaim pages reclaimed 88599 47535 47863 46671 Direct reclaim write file async I/O 494 283 465 280 Direct reclaim write anon async I/O 29357 13710 16656 13462 Direct reclaim write file sync I/O 154 2 2 3 Direct reclaim write anon sync I/O 14594 571 509 561 Wake kswapd requests 7491 933 872 892 Kswapd wakeups 814 778 731 780 Kswapd pages scanned 7290822 15341158 11916436 13703442 Kswapd pages reclaimed 3587336 3142496 3094392 3187151 Kswapd reclaim write file async I/O 91975 32317 28022 29628 Kswapd reclaim write anon async I/O 1992022 789307 829745 849769 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 4588.93 2467.16 2495.41 2547.07 Time kswapd awake (seconds) 2497.66 1020.16 1098.06 1176.82 Total pages scanned 7425913 15460762 12025818 13804461 Total pages reclaimed 3675935 3190031 3142255 3233822 %age total pages scanned/reclaimed 49.50% 20.63% 26.13% 23.43% %age total pages scanned/written 28.66% 5.41% 7.28% 6.47% %age file pages scanned/written 1.25% 0.21% 0.24% 0.22% Percentage Time Spent Direct Reclaim 57.33% 42.15% 42.41% 42.99% Percentage Time kswapd Awake 43.56% 27.87% 29.76% 31.25% Scanned/reclaimed ratios again look good with big improvements in efficiency. The Scanned/written ratios also look much improved. With a better scanned/written ration, there is an expectation that IO would be more efficient and indeed, the time spent in direct reclaim is much reduced by the full series and kswapd spends a little less time awake. Overall, indications here are that allocations were happening much faster and this can be seen with a graph of the latency figures as the allocations were taking place http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-hydra-mean.ps FTrace Reclaim Statistics: congestion_wait Direct number congest waited 1333 204 169 4 Direct time congest waited 78896ms 8288ms 7260ms 200ms Direct full congest waited 756 92 69 2 Direct number conditional waited 0 0 26 186 Direct time conditional waited 0ms 0ms 0ms 2504ms Direct full conditional waited 0 0 0 25 KSwapd number congest waited 4 395 227 282 KSwapd time congest waited 384ms 25136ms 10508ms 18380ms KSwapd full congest waited 3 232 98 176 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 KSwapd full conditional waited 318 0 312 9 Overall, the time spent speeping is reduced. kswapd is still hitting congestion_wait() but that is because there are callers remaining where it wasn't clear in advance if they should be changed to wait_iff_congested() or not. Overall the sleep imes are reduced though - from 79ish seconds to about 19. MMTests Statistics: duration User/Sys Time Running Test (seconds) 3415.43 3386.65 3388.39 3377.5 Total Elapsed Time (seconds) 5733.48 3660.33 3689.41 3765.39 With the full series, the time to complete the tests are reduced by 30% PPC64 STRESS-HIGHALLOC traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Pass 1 17.00 ( 0.00%) 34.00 (17.00%) 38.00 (21.00%) 43.00 (26.00%) Pass 2 25.00 ( 0.00%) 37.00 (12.00%) 42.00 (17.00%) 46.00 (21.00%) At Rest 49.00 ( 0.00%) 43.00 (-6.00%) 45.00 (-4.00%) 51.00 ( 2.00%) Success rates there are *way* up particularly considering that the 16MB huge pages on PPC64 mean that it's always much harder to allocate them. FTrace Reclaim Statistics: vmscan stress-highalloc stress-highalloc stress-highalloc stress-highalloc traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Direct reclaims 499 505 564 509 Direct reclaim pages scanned 223478 41898 51818 45605 Direct reclaim pages reclaimed 137730 21148 27161 23455 Direct reclaim write file async I/O 399 136 162 136 Direct reclaim write anon async I/O 46977 2865 4686 3998 Direct reclaim write file sync I/O 29 0 1 3 Direct reclaim write anon sync I/O 31023 159 237 239 Wake kswapd requests 420 351 360 326 Kswapd wakeups 185 294 249 277 Kswapd pages scanned 15703488 16392500 17821724 17598737 Kswapd pages reclaimed 5808466 2908858 3139386 3145435 Kswapd reclaim write file async I/O 159938 18400 18717 13473 Kswapd reclaim write anon async I/O 3467554 228957 322799 234278 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 9665.35 1707.81 2374.32 1871.23 Time kswapd awake (seconds) 9401.21 1367.86 1951.75 1328.88 Total pages scanned 15926966 16434398 17873542 17644342 Total pages reclaimed 5946196 2930006 3166547 3168890 %age total pages scanned/reclaimed 37.33% 17.83% 17.72% 17.96% %age total pages scanned/written 23.27% 1.52% 1.94% 1.43% %age file pages scanned/written 1.01% 0.11% 0.11% 0.08% Percentage Time Spent Direct Reclaim 44.55% 35.10% 41.42% 36.91% Percentage Time kswapd Awake 86.71% 43.58% 52.67% 41.14% While the scanning rates are slightly up, the scanned/reclaimed and scanned/written figures are much improved. The time spent in direct reclaim and with kswapd are massively reduced, mostly by the lowlumpy patches. FTrace Reclaim Statistics: congestion_wait Direct number congest waited 725 303 126 3 Direct time congest waited 45524ms 9180ms 5936ms 300ms Direct full congest waited 487 190 52 3 Direct number conditional waited 0 0 200 301 Direct time conditional waited 0ms 0ms 0ms 1904ms Direct full conditional waited 0 0 0 19 KSwapd number congest waited 0 2 23 4 KSwapd time congest waited 0ms 200ms 420ms 404ms KSwapd full congest waited 0 2 2 4 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 Not as dramatic a story here but the time spent asleep is reduced and we can still see what wait_iff_congested is going to sleep when necessary. MMTests Statistics: duration User/Sys Time Running Test (seconds) 12028.09 3157.17 3357.79 3199.16 Total Elapsed Time (seconds) 10842.07 3138.72 3705.54 3229.85 The time to complete this test goes way down. With the full series, we are allocating over twice the number of huge pages in 30% of the time and there is a corresponding impact on the allocation latency graph available at. http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-powyah-mean.ps This patch: Add a trace event for shrink_inactive_list() and updates the sample postprocessing script appropriately. It can be used to determine how many pages were reclaimed and for non-lumpy reclaim where exactly the pages were reclaimed from. Signed-off-by: NMel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org> -
由 Will Deacon 提交于
NODE_NOT_IN_PAGE_FLAGS is defined in mm.h when the node information is not stored in the page flags bitmap. Unfortunately, there's a typo in one of the checks for it. This patch fixes it (s/NODE_NOT_IN_PAGEFLAGS/NODE_NOT_IN_PAGE_FLAGS/). Since this has been around for ages, I doubt it's been causing any serious problems. Signed-off-by: NWill Deacon <will.deacon@arm.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michael Rubin 提交于
To help developers and applications gain visibility into writeback behaviour adding two entries to vm_stat_items and /proc/vmstat. This will allow us to track the "written" and "dirtied" counts. # grep nr_dirtied /proc/vmstat nr_dirtied 3747 # grep nr_written /proc/vmstat nr_written 3618 Signed-off-by: NMichael Rubin <mrubin@google.com> Reviewed-by: NWu Fengguang <fengguang.wu@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michael Rubin 提交于
To help developers and applications gain visibility into writeback behaviour this patch adds two counters to /proc/vmstat. # grep nr_dirtied /proc/vmstat nr_dirtied 3747 # grep nr_written /proc/vmstat nr_written 3618 These entries allow user apps to understand writeback behaviour over time and learn how it is impacting their performance. Currently there is no way to inspect dirty and writeback speed over time. It's not possible for nr_dirty/nr_writeback. These entries are necessary to give visibility into writeback behaviour. We have /proc/diskstats which lets us understand the io in the block layer. We have blktrace for more in depth understanding. We have e2fsprogs and debugsfs to give insight into the file systems behaviour, but we don't offer our users the ability understand what writeback is doing. There is no way to know how active it is over the whole system, if it's falling behind or to quantify it's efforts. With these values exported users can easily see how much data applications are sending through writeback and also at what rates writeback is processing this data. Comparing the rates of change between the two allow developers to see when writeback is not able to keep up with incoming traffic and the rate of dirty memory being sent to the IO back end. This allows folks to understand their io workloads and track kernel issues. Non kernel engineers at Google often use these counters to solve puzzling performance problems. Patch #4 adds a pernode vmstat file with nr_dirtied and nr_written Patch #5 add writeback thresholds to /proc/vmstat Currently these values are in debugfs. But they should be promoted to /proc since they are useful for developers who are writing databases and file servers and are not debugging the kernel. The output is as below: # grep threshold /proc/vmstat nr_pages_dirty_threshold 409111 nr_pages_dirty_background_threshold 818223 This patch: This allows code outside of the mm core to safely manipulate page writeback state and not worry about the other accounting. Not using these routines means that some code will lose track of the accounting and we get bugs. Modify nilfs2 to use interface. Signed-off-by: NMichael Rubin <mrubin@google.com> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: NWu Fengguang <fengguang.wu@intel.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Jiro SEKIBA <jir@unicus.jp> Cc: Dave Chinner <david@fromorbit.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-