- 07 Apr, 2014 40 commits
-
-
Vladimir Davydov authored
Currently, we try to arrange sysfs entries for memcg caches in the same manner as for global caches. Apart from turning /sys/kernel/slab into a mess when there are a lot of kmem-active memcgs created, it actually does not work properly - we won't create more than one link to a memcg cache in case its parent is merged with another cache. For instance, if A is a root cache merged with another root cache B, we will have the following sysfs setup: X A -> X B -> X where X is some unique id (see create_unique_id()). Now if memcgs M and N start to allocate from cache A (or B, which is the same), we will get: X X:M X:N A -> X B -> X A:M -> X:M A:N -> X:N Since B is an alias for A, we won't get entries B:M and B:N, which is confusing. It is more logical to have entries for memcg caches under the corresponding root cache's sysfs directory. This would allow us to keep sysfs layout clean, and avoid such inconsistencies like one described above. This patch does the trick. It creates a "cgroup" kset in each root cache kobject to keep its children caches there. Signed-off-by:
Vladimir Davydov <vdavydov@parallels.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Glauber Costa <glommer@gmail.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Vladimir Davydov authored
Otherwise, kzalloc() called from a memcg won't clear the whole object. Signed-off-by:
-
Vladimir Davydov authored
Currently we destroy children caches at the very beginning of kmem_cache_destroy(). This is wrong, because the root cache will not necessarily be destroyed in the end - if it has aliases (refcount > 0), kmem_cache_destroy() will simply decrement its refcount and return. In this case, at best we will get a bunch of warnings in dmesg, like this one: kmem_cache_destroy kmalloc-32:0: Slab cache still has objects CPU: 1 PID: 7139 Comm: modprobe Tainted: G B W 3.13.0+ #117 Call Trace: dump_stack+0x49/0x5b kmem_cache_destroy+0xdf/0xf0 kmem_cache_destroy_memcg_children+0x97/0xc0 kmem_cache_destroy+0xf/0xf0 xfs_mru_cache_uninit+0x21/0x30 [xfs] exit_xfs_fs+0x2e/0xc44 [xfs] SyS_delete_module+0x198/0x1f0 system_call_fastpath+0x16/0x1b At worst - if kmem_cache_destroy() will race with an allocation from a memcg cache - the kernel will panic. This patch fixes this by moving children caches destruction after the check if the cache has aliases. Plus, it forbids destroying a root cache if it still has children caches, because each children cache keeps a reference to its parent. Signed-off-by: -
Vladimir Davydov authored
Currently, memcg_unregister_cache(), which deletes the cache being destroyed from the memcg_slab_caches list, is called after __kmem_cache_shutdown() (see kmem_cache_destroy()), which starts to destroy the cache. As a result, one can access a partially destroyed cache while traversing a memcg_slab_caches list, which can have deadly consequences (for instance, cache_show() called for each cache on a memcg_slab_caches list from mem_cgroup_slabinfo_read() will dereference pointers to already freed data). To fix this, let's move memcg_unregister_cache() before the cache destruction process beginning, issuing memcg_register_cache() on failure. Signed-off-by:
-
Vladimir Davydov authored
Memcg-awareness turned kmem_cache_create() into a dirty interweaving of memcg-only and except-for-memcg calls. To clean this up, let's move the code responsible for memcg cache creation to a separate function. Signed-off-by:
-
Vladimir Davydov authored
This patch cleans up the memcg cache creation path as follows: - Move memcg cache name creation to a separate function to be called from kmem_cache_create_memcg(). This allows us to get rid of the mutex protecting the temporary buffer used for the name formatting, because the whole cache creation path is protected by the slab_mutex. - Get rid of memcg_create_kmem_cache(). This function serves as a proxy to kmem_cache_create_memcg(). After separating the cache name creation path, it would be reduced to a function call, so let's inline it. Signed-off-by:
-
Vladimir Davydov authored
When a kmem cache is created (kmem_cache_create_memcg()), we first try to find a compatible cache that already exists and can handle requests from the new cache, i.e. has the same object size, alignment, ctor, etc. If there is such a cache, we do not create any new caches, instead we simply increment the refcount of the cache found and return it. Currently we do this procedure not only when creating root caches, but also for memcg caches. However, there is no point in that, because, as every memcg cache has exactly the same parameters as its parent and cache merging cannot be turned off in runtime (only on boot by passing "slub_nomerge"), the root caches of any two potentially mergeable memcg caches should be merged already, i.e. it must be the same root cache, and therefore we couldn't even get to the memcg cache creation, because it already exists. The only exception is boot caches - they are explicitly forbidden to be merged by setting their refcount to -1. There are currently only two of them - kmem_cache and kmem_cache_node, which are used in slab internals (I do not count kmalloc caches as their refcount is set to 1 immediately after creation). Since they are prevented from merging preliminary I guess we should avoid to merge their children too. So let's remove the useless code responsible for merging memcg caches. Signed-off-by:
-
David Howells authored
arch_align_stack() moved to asm/exec.h, so change the comment referring to asm/system.h which no longer exists. Signed-off-by:
David Howells <dhowells@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by:
-
David Howells authored
Clean asm/system.h from docs as nothing should refer to that header anymore. Signed-off-by:
-
Gideon Israel Dsouza authored
To increase compiler portability there is <linux/compiler.h> which provides convenience macros for various gcc constructs. Eg: __weak for __attribute__((weak)). I've replaced all instances of gcc attributes with the right macro in the kernel subsystem. Signed-off-by:
Gideon Israel Dsouza <gidisrael@gmail.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by:
-
Uwe Kleine-König authored
If the renamed symbol is defined lib/iomap.c implements ioport_map and ioport_unmap and currently (nearly) all platforms define the port accessor functions outb/inb and friend unconditionally. So HAS_IOPORT_MAP is the better name for this. Consequently NO_IOPORT is renamed to NO_IOPORT_MAP. The motivation for this change is to reintroduce a symbol HAS_IOPORT that signals if outb/int et al are available. I will address that at least one merge window later though to keep surprises to a minimum and catch new introductions of (HAS|NO)_IOPORT. The changes in this commit were done using: $ git grep -l -E '(NO|HAS)_IOPORT' | xargs perl -p -i -e 's/\b((?:CONFIG_)?(?:NO|HAS)_IOPORT)\b/$1_MAP/' Signed-off-by:
Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
-
Davidlohr Bueso authored
... since __initcall is now deprecated. Signed-off-by:
Davidlohr Bueso <davidlohr@hp.com> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by:
-
Davidlohr Bueso authored
This macro appears to have been introduced back in the 2.5 era for semtimedop32 backward compatibility on ia32: https://lkml.org/lkml/2003/4/28/78 Nowadays, this syscall in compat just defaults back to the code found in sem.c, so it is no longer used and can thus be removed: long compat_sys_semtimedop(int semid, struct sembuf __user *tsems, unsigned nsops, const struct compat_timespec __user *timeout) { struct timespec __user *ts64; if (compat_convert_timespec(&ts64, timeout)) return -EFAULT; return sys_semtimedop(semid, tsems, nsops, ts64); } Furthermore, there are no users in compat.c. After this change, kernel builds just fine with both CONFIG_SYSVIPC_COMPAT and CONFIG_SYSVIPC. Signed-off-by:
-
Daniel M. Weeks authored
This can greatly aid in narrowing down the real source of initramfs problems such as failures related to the compression of the in-kernel initramfs when an external initramfs is in use as well. Existing errors are ambiguous as to which initramfs is a problem and why. [akpm@linux-foundation.org: use pr_debug()] Signed-off-by:
Daniel M. Weeks <dan@danweeks.net> Signed-off-by:
-
Dave Jones authored
/proc/self/make-it-fail is a boolean, but accepts any number, including negative ones. Change variable to unsigned, and cap upper bound at 1. [akpm@linux-foundation.org: don't make make_it_fail unsigned] Signed-off-by:
Dave Jones <davej@fedoraproject.org> Reviewed-by:
Akinobu Mita <akinobu.mita@gmail.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by:
-
Josh Triplett authored
This ensures that BUG() always has a definition that causes a trap (via an undefined instruction), and that the compiler still recognizes the code following BUG() as unreachable, avoiding warnings that would otherwise appear (such as on non-void functions that don't return a value after BUG()). In addition to saving a few bytes over the generic infinite-loop implementation, this implementation traps rather than looping, which potentially allows for better error-recovery behavior (such as by rebooting). Signed-off-by:
Josh Triplett <josh@joshtriplett.org> Reported-by:
-
Josh Triplett authored
When !CONFIG_BUG and !HAVE_ARCH_BUG, define the generic BUG() as an infinite loop rather than a no-op. This avoids undefined behavior if execution ever actually reaches BUG(), and avoids warnings about code after BUG() (such as on non-void functions calling BUG() and then not returning). bloat-o-meter results: add/remove: 0/0 grow/shrink: 43/10 up/down: 235/-98 (137) function old new delta umount_collect 119 138 +19 notify_change 306 324 +18 xstate_enable_boot_cpu 252 269 +17 kunmap 54 70 +16 balloon_page_dequeue 112 126 +14 mm_take_all_locks 223 233 +10 list_lru_walk_node 143 152 +9 vma_adjust 1059 1067 +8 pcpu_setup_first_chunk 1130 1138 +8 mm_drop_all_locks 143 151 +8 ns_capable 55 62 +7 anon_transport_class_unregister 8 15 +7 srcu_init_notifier_head 35 41 +6 shrink_dcache_for_umount 174 180 +6 kunmap_high 99 105 +6 end_page_writeback 43 49 +6 do_exit 1339 1345 +6 __kfifo_dma_out_prepare_r 86 92 +6 __kfifo_dma_in_prepare_r 90 96 +6 fixup_user_fault 120 125 +5 repair_env_string 73 77 +4 read_cache_pages_invalidate_page 56 60 +4 isolate_lru_pages.isra 142 146 +4 do_notify_parent_cldstop 255 259 +4 cpu_init 370 374 +4 utimes_common 270 272 +2 tasklet_hi_action 91 93 +2 tasklet_action 91 93 +2 set_pte_vaddr 46 48 +2 find_get_pages_tag 202 204 +2 early_iounmap 185 187 +2 __native_set_fixmap 36 38 +2 __get_user_pages 822 824 +2 __early_ioremap 299 301 +2 yield_task_stop 1 2 +1 tick_resume 37 38 +1 switched_to_stop 1 2 +1 switched_to_idle 1 2 +1 prio_changed_stop 1 2 +1 prio_changed_idle 1 2 +1 pm_qos_power_read 111 112 +1 arch_cpu_idle_dead 1 2 +1 __insert_vmap_area 140 141 +1 sys_renameat 614 612 -2 mm_fault_error 297 295 -2 SyS_renameat 614 612 -2 sys_linkat 416 413 -3 SyS_linkat 416 413 -3 chmod_common 129 122 -7 proc_cap_handler 240 225 -15 __schedule 849 831 -18 sys_madvise 1077 1054 -23 SyS_madvise 1077 1054 -23 Signed-off-by:
-
Josh Triplett authored
The stub version of WARN for !CONFIG_BUG completely ignored its format string and subsequent arguments; make it check them instead, using no_printk. Signed-off-by:
-
Josh Triplett authored
Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Acked-by:
-
Josh Triplett authored
When !CONFIG_BUG, WARN_ON and family become simple passthroughs of their condition argument; however, WARN_ON_ONCE and family still have conditions and a boolean to detect one-time invocation, even though the warning they'd emit doesn't exist. Make the existing definitions conditional on CONFIG_BUG, and add definitions for !CONFIG_BUG that map to the passthrough versions of WARN and WARN_ON. This saves 4.4k on a minimized configuration (smaller than allnoconfig), and 20.6k with defconfig plus CONFIG_BUG=n. Signed-off-by:
-
Josh Triplett authored
"make allnoconfig" exists to ease testing of minimal configurations. Documentation/SubmitChecklist includes a note to test with allnoconfig. This helps catch missing dependencies on common-but-not-required functionality, which might otherwise go unnoticed. However, allnoconfig still leaves many symbols enabled, because they're hidden behind CONFIG_EMBEDDED or CONFIG_EXPERT. For instance, allnoconfig still has CONFIG_PRINTK and CONFIG_BLOCK enabled, so drivers don't typically get build-tested with those disabled. To address this, introduce a new Kconfig option "allnoconfig_y", used on symbols which only exist to hide other symbols. Set it on CONFIG_EMBEDDED (which then selects CONFIG_EXPERT). allnoconfig will then disable all the symbols hidden behind those. Signed-off-by:
Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by:
-
Josh Triplett authored
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT". arch/powerpc/kernel/mce.c, compiled in for PPC_BOOK3S_64, calls functions only built when IRQ_WORK, so select it. Fixes the following build error: arch/powerpc/kernel/built-in.o: In function `.machine_check_queue_event': (.text+0x11260): undefined reference to `.irq_work_queue' Signed-off-by:
Stephen Rothwell <sfr@canb.auug.org.au> Acked-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
-
Josh Triplett authored
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT". arch/ia64/kernel/unaligned.c uses tty_write_message to print an unaligned access exception to the TTY of the current user process. Enable TTY to prevent a build error. Minimal fix, on the basis that few people on ia64 will care deeply about kernel size enough to turn off TTY. Ideally, I'd instead suggest dropping the tty_write_message entirely, and just leaving the printk. Bonus: no need to sprintf first. Signed-off-by:
-
Geert Uytterhoeven authored
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT". Now allnoconfig started disabling CONFIG_PROC_FS: arch/cris/kernel/built-in.o:(.rodata+0xc): undefined reference to `show_cpuinfo' make: *** [vmlinux] Error 1 Signed-off-by:Geert Uytterhoeven <geert@linux-m68k.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by:
-
Josh Triplett authored
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT". arch/cris/arch-v10/kernel/debugport.c, compiled in unconditionally with ETRAX_ARCH_V10, requires TTY, so select TTY to avoid a build failure. Signed-off-by:
-
Dan Carpenter authored
"ret" is zero here so we can remove the "!ret" part of the condition. "uhdr" is alread a __user pointer so we can remove the cast. Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Acked-by:
Dimitri Sivanich <sivanich@sgi.com> Signed-off-by:
-
Fabian Frederick authored
Currently, booting without initrd specified on 80x25 screen gives a call trace followed by atkbd : Spurious ACK. Original message ("VFS: Unable to mount root fs") is not available. Of course this could happen in other situations... This patch displays panic reason after call trace which could help lot of people even if it's not the very last line on screen. Also, convert all panic.c printk(KERN_EMERG to pr_emerg( [akpm@linux-foundation.org: missed a couple of pr_ conversions] Signed-off-by:Fabian Frederick <fabf@skynet.be> Signed-off-by:
-
Fabian Frederick authored
init_inodecache is only called by __init init_bfs_fs Signed-off-by:
-
Fabian Frederick authored
Normal behavior for filenames exceeding specific filesystem limits is to refuse operation. AFFS standard name length being only 30 characters against 255 for usual Linux filesystems, original implementation does filename truncate by default with a define value AFFS_NO_TRUNCATE which can be enabled but needs module compilation. This patch adds 'nofilenametruncate' mount option so that user can easily activate that feature and avoid a lot of problems (eg overwrite files ...) Signed-off-by:
-
Fabian Frederick authored
Commit 0edf977d ("[readdir] convert affs") returns directly -EIO without unlocking dir inode and releasing dir bh when second affs_bread sequence fails. This patch restores initial behaviour. It also fixes pr_debug and affs_error to fit in 80 columns + removes reference to filldir (replaced by dir_emit in the commit above). Signed-off-by:
-
Fabian Frederick authored
init_inodecache is only called by __init init_affs_fs Signed-off-by:
-
Fabian Frederick authored
init_inodecache is only called by __init init_adfs_fs. Signed-off-by:
-
Liu Hua authored
As sysctl_hung_task_timeout_sec is unsigned long, when this value is larger then LONG_MAX/HZ, the function schedule_timeout_interruptible in watchdog will return immediately without sleep and with print : schedule_timeout: wrong timeout value ffffffffffffff83 and then the funtion watchdog will call schedule_timeout_interruptible again and again. The screen will be filled with "schedule_timeout: wrong timeout value ffffffffffffff83" This patch does some check and correction in sysctl, to let the function schedule_timeout_interruptible allways get the valid parameter. Signed-off-by:
Liu Hua <sdu.liu@huawei.com> Tested-by:
Satoru Takeuchi <satoru.takeuchi@gmail.com> Cc: <stable@vger.kernel.org> [3.4+] Signed-off-by:
-
Alexandre Bounine authored
This patch removes an artificial RapidIO bus root device and establishes actual device hierarchy by providing reference to real parent devices. It also introduces device class for RapidIO controller devices (on-chip or an eternal bridge, known as "mport"). Existing implementation was sufficient for SoC-based platforms that have a single RapidIO controller. With introduction of devices using multiple RapidIO controllers and PCIe-to-RapidIO bridges the old scheme is very limiting or does not work at all. The implemented changes allow to properly reference platform's local RapidIO mport devices and provide device details needed for upper layers. This change to RapidIO device hierarchy does not break any known existing kernel or user space interfaces. Signed-off-by:
Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Li Yang <leoli@freescale.com> Cc: Kumar Gala <galak@kernel.crashing.org> Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com> Cc: Stef van Os <stef.van.os@prodrive-technologies.com> Cc: Jerry Jacobs <jerry.jacobs@prodrive-technologies.com> Cc: Arno Tiemersma <arno.tiemersma@prodrive-technologies.com> Cc: Rob Landley <rob@landley.net> Signed-off-by:
-
Alexandre Bounine authored
Combine SG entries describing single contiguous memory block into one Tsi721 BDMA descriptor. This reduces number of hardware descriptors required for large data transfers and improves performance on the PCIe side by reducing number of descriptor fetch requests. Signed-off-by:
-
Monam Agarwal authored
Replace rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL) The rcu_assign_pointer() ensures that the initialization of a structure is carried out before storing a pointer to that structure. And in the case of the NULL pointer, there is no structure to initialize. So, rcu_assign_pointer(p, NULL) can be safely converted to RCU_INIT_POINTER(p, NULL) Signed-off-by:
Monam Agarwal <monamagarwal123@gmail.com> Acked-by:
Tejun Heo <tj@kernel.org> Signed-off-by:
-
Stephen Hemminger authored
Remove no longer used deprecated code, and make local functions static. Signed-off-by:
Stephen Hemminger <stephen@networkplumber.org> Acked-by:
Jean Delvare <jdelvare@suse.de> Acked-by:
-
WANG Chao authored
Currently when an empty PT_NOTE is detected, vmcore initialization fails. It sounds too harsh. Because PT_NOTE could be empty, for example, one offlined a cpu but never restarted kdump service, and after crash, PT_NOTE program header is there but no data contains. It's better to warn about the empty PT_NOTE and continue to initialise vmcore. And ultimately the multiple PT_NOTE are merged into a single one, all empty PT_NOTE are discarded naturally during the merge. So empty PT_NOTE is not visible to user space and vmcore is as good as expected. Signed-off-by:
WANG Chao <chaowang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Greg Pearson <greg.pearson@hp.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by:
-
Rashika Kheria authored
Eliminate the following warning in proc/vmcore.c: fs/proc/vmcore.c:1088:6: warning: no previous prototype for `vmcore_cleanup' [-Wmissing-prototypes] [akpm@linux-foundation.org: clean up powerpc, remove unneeded EXPORT_SYMBOL] Signed-off-by:
Rashika Kheria <rashika.kheria@gmail.com> Reviewed-by:
-
Oleg Nesterov authored
Even if the main thread is dead the process still can stop/continue. However, if the leader is ptraced wait_consider_task(ptrace => false) always skips wait_task_stopped/wait_task_continued, so WSTOPPED or WCONTINUED can never work for the natural parent in this case. Move the "A zombie ptracee is only visible to its ptracer" check into the "if (!delay_group_leader(p))" block. ->notask_error is cleared by the "fall through" code below. This depends on the previous change, wait_task_stopped/continued must be avoided if !delay_group_leader() and the tracer is ->real_parent. Otherwise WSTOPPED|WEXITED could wrongly report "stopped" when the child is already dead (single-threaded or not). If it is traced by another task then the "stopped" state is fine until the debugger detaches and reveals a zombie state. Stupid test-case: void *tfunc(void *arg) { sleep(1); // wait for zombie leader raise(SIGSTOP); exit(0x13); return NULL; } int run_child(void) { pthread_t thread; if (!fork()) { int tracee = getppid(); assert(ptrace(PTRACE_ATTACH, tracee, 0,0) == 0); do ptrace(PTRACE_CONT, tracee, 0,0); while (wait(NULL) > 0); return 0; } sleep(1); // wait for PTRACE_ATTACH assert(pthread_create(&thread, NULL, tfunc, NULL) == 0); pthread_exit(NULL); } int main(void) { int child, stat; child = fork(); if (!child) return run_child(); assert(child == waitpid(-1, &stat, WSTOPPED)); assert(stat == 0x137f); kill(child, SIGCONT); assert(child == waitpid(-1, &stat, WCONTINUED)); assert(stat == 0xffff); assert(child == waitpid(-1, &stat, 0)); assert(stat == 0x1300); return 0; } Without this patch it hangs in waitpid(WSTOPPED), wait_task_stopped() is never called. Note: this doesn't fix all problems with a zombie delay_group_leader(), WCONTINUED | WEXITED check is not exactly right. debugger can't assume it will be notified if another thread reaps the whole thread group. Signed-off-by:Oleg Nesterov <oleg@redhat.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Lennart Poettering <lpoetter@redhat.com> Cc: Michal Schmidt <mschmidt@redhat.com> Cc: Roland McGrath <roland@hack.frob.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by:
-
