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2020-01-12locking/x86: Remove the unused atomic_inc_short() methdDmitry Vyukov
commit 31b35f6b4d5285a311e10753f4eb17304326b211 upstream. It is completely unused and implemented only on x86. Remove it. Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170526172900.91058-1-dvyukov@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-25x86/atomic: Fix smp_mb__{before,after}_atomic()Peter Zijlstra
commit 69d927bba39517d0980462efc051875b7f4db185 upstream. Recent probing at the Linux Kernel Memory Model uncovered a 'surprise'. Strongly ordered architectures where the atomic RmW primitive implies full memory ordering and smp_mb__{before,after}_atomic() are a simple barrier() (such as x86) fail for: *x = 1; atomic_inc(u); smp_mb__after_atomic(); r0 = *y; Because, while the atomic_inc() implies memory order, it (surprisingly) does not provide a compiler barrier. This then allows the compiler to re-order like so: atomic_inc(u); *x = 1; smp_mb__after_atomic(); r0 = *y; Which the CPU is then allowed to re-order (under TSO rules) like: atomic_inc(u); r0 = *y; *x = 1; And this very much was not intended. Therefore strengthen the atomic RmW ops to include a compiler barrier. NOTE: atomic_{or,and,xor} and the bitops already had the compiler barrier. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jari Ruusu <jari.ruusu@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-25Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: "Various x86 low level modifications: - preparatory work to support virtually mapped kernel stacks (Andy Lutomirski) - support for 64-bit __get_user() on 32-bit kernels (Benjamin LaHaise) - (involved) workaround for Knights Landing CPU erratum (Dave Hansen) - MPX enhancements (Dave Hansen) - mremap() extension to allow remapping of the special VDSO vma, for purposes of user level context save/restore (Dmitry Safonov) - hweight and entry code cleanups (Borislav Petkov) - bitops code generation optimizations and cleanups with modern GCC (H. Peter Anvin) - syscall entry code optimizations (Paolo Bonzini)" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits) x86/mm/cpa: Add missing comment in populate_pdg() x86/mm/cpa: Fix populate_pgd(): Stop trying to deallocate failed PUDs x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2 x86/smp: Remove unnecessary initialization of thread_info::cpu x86/smp: Remove stack_smp_processor_id() x86/uaccess: Move thread_info::addr_limit to thread_struct x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct x86/dumpstack: When OOPSing, rewind the stack before do_exit() x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm x86/dumpstack/64: Handle faults when printing the "Stack: " part of an OOPS x86/dumpstack: Try harder to get a call trace on stack overflow x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated x86/mm/hotplug: Don't remove PGD entries in remove_pagetable() x86/mm: Use pte_none() to test for empty PTE x86/mm: Disallow running with 32-bit PTEs to work around erratum x86/mm: Ignore A/D bits in pte/pmd/pud_none() x86/mm: Move swap offset/type up in PTE to work around erratum x86/entry: Inline enter_from_user_mode() ...
2016-06-16locking/atomic: Remove linux/atomic.h:atomic_fetch_or()Peter Zijlstra
Since all architectures have this implemented now natively, remove this dead code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-16locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()Peter Zijlstra
Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08x86, asm: change the GEN_*_RMWcc() macros to not quote the conditionH. Peter Anvin
Change the lexical defintion of the GEN_*_RMWcc() macros to not take the condition code as a quoted string. This will help support changing them to use the new __GCC_ASM_FLAG_OUTPUTS__ feature in a subsequent patch. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1465414726-197858-4-git-send-email-hpa@linux.intel.com Reviewed-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-06-08x86, asm: use bool for bitops and other assembly outputsH. Peter Anvin
The gcc people have confirmed that using "bool" when combined with inline assembly always is treated as a byte-sized operand that can be assumed to be 0 or 1, which is exactly what the SET instruction emits. Change the output types and intermediate variables of as many operations as practical to "bool". Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1465414726-197858-3-git-send-email-hpa@linux.intel.com Reviewed-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2015-12-06x86/headers: Don't include asm/processor.h in asm/atomic.hAndi Kleen
asm/atomic.h doesn't really need asm/processor.h anymore. Everything it uses has moved to other header files. So remove that include. processor.h is a nasty header that includes lots of other headers and makes it prone to include loops. Removing the include here makes asm/atomic.h a "leaf" header that can be safely included in most other headers. The only fallout is in the lib/atomic tester which relied on this implicit include. Give it an explicit include. (the include is in ifdef because the user is also in ifdef) Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: rostedt@goodmis.org Link: http://lkml.kernel.org/r/1449018060-1742-1-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-23atomic, arch: Audit atomic_{read,set}()Peter Zijlstra
This patch makes sure that atomic_{read,set}() are at least {READ,WRITE}_ONCE(). We already had the 'requirement' that atomic_read() should use ACCESS_ONCE(), and most archs had this, but a few were lacking. All are now converted to use READ_ONCE(). And, by a symmetry and general paranoia argument, upgrade atomic_set() to use WRITE_ONCE(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: james.hogan@imgtec.com Cc: linux-kernel@vger.kernel.org Cc: oleg@redhat.com Cc: will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-27atomic: Collapse all atomic_{set,clear}_mask definitionsPeter Zijlstra
Move the now generic definitions of atomic_{set,clear}_mask() into linux/atomic.h to avoid endless and pointless repetition. Also, provide an atomic_andnot() wrapper for those few archs that can implement that. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27atomic: Provide atomic_{or,xor,and}Peter Zijlstra
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27x86: Provide atomic_{or,xor,and}Peter Zijlstra
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-08x86: Force inlining of atomic opsDenys Vlasenko
With both gcc 4.7.2 and 4.9.2, sometimes gcc mysteriously doesn't inline very small functions we expect to be inlined: $ nm --size-sort vmlinux | grep -iF ' t ' | uniq -c | grep -v '^ *1 ' | sort -rn 473 000000000000000b t spin_unlock_irqrestore 449 000000000000005f t rcu_read_unlock 355 0000000000000009 t atomic_inc <== THIS 353 000000000000006e t rcu_read_lock 350 0000000000000075 t rcu_read_lock_sched_held 291 000000000000000b t spin_unlock 266 0000000000000019 t arch_local_irq_restore 215 000000000000000b t spin_lock 180 0000000000000011 t kzalloc 165 0000000000000012 t list_add_tail 161 0000000000000019 t arch_local_save_flags 153 0000000000000016 t test_and_set_bit 134 000000000000000b t spin_unlock_irq 134 0000000000000009 t atomic_dec <== THIS 130 000000000000000b t spin_unlock_bh 122 0000000000000010 t brelse 120 0000000000000016 t test_and_clear_bit 120 000000000000000b t spin_lock_irq 119 000000000000001e t get_dma_ops 117 0000000000000053 t cpumask_next 116 0000000000000036 t kref_get 114 000000000000001a t schedule_work 106 000000000000000b t spin_lock_bh 103 0000000000000019 t arch_local_irq_disable ... Note sizes of marked functions. They are merely 9 bytes long! Selecting function with 'atomic' in their names: 355 0000000000000009 t atomic_inc 134 0000000000000009 t atomic_dec 98 0000000000000014 t atomic_dec_and_test 31 000000000000000e t atomic_add_return 27 000000000000000a t atomic64_inc 26 000000000000002f t kmap_atomic 24 0000000000000009 t atomic_add 12 0000000000000009 t atomic_sub 10 0000000000000021 t __atomic_add_unless 10 000000000000000a t atomic64_add 5 000000000000001f t __atomic_add_unless.constprop.7 5 000000000000000a t atomic64_dec 4 000000000000001f t __atomic_add_unless.constprop.18 4 000000000000001f t __atomic_add_unless.constprop.12 4 000000000000001f t __atomic_add_unless.constprop.10 3 000000000000001f t __atomic_add_unless.constprop.13 3 0000000000000011 t atomic64_add_return 2 000000000000001f t __atomic_add_unless.constprop.9 2 000000000000001f t __atomic_add_unless.constprop.8 2 000000000000001f t __atomic_add_unless.constprop.6 2 000000000000001f t __atomic_add_unless.constprop.5 2 000000000000001f t __atomic_add_unless.constprop.3 2 000000000000001f t __atomic_add_unless.constprop.22 2 000000000000001f t __atomic_add_unless.constprop.14 2 000000000000001f t __atomic_add_unless.constprop.11 2 000000000000001e t atomic_dec_if_positive 2 0000000000000014 t atomic_inc_and_test 2 0000000000000011 t atomic_add_return.constprop.4 2 0000000000000011 t atomic_add_return.constprop.17 2 0000000000000011 t atomic_add_return.constprop.16 2 000000000000000d t atomic_inc.constprop.4 2 000000000000000c t atomic_cmpxchg This patch fixes this for x86 atomic ops via s/inline/__always_inline/. This decreases allyesconfig kernel by about 25k: text data bss dec hex filename 82399481 22255416 20627456 125282353 777a831 vmlinux.before 82375570 22255544 20627456 125258570 7774b4a vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1431080762-17797-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-22x86/asm: Always inline atomicsHagen Paul Pfeifer
During some code analysis I realized that atomic_add(), atomic_sub() and friends are not necessarily inlined AND that each function is defined multiple times: atomic_inc: 544 duplicates atomic_dec: 215 duplicates atomic_dec_and_test: 107 duplicates atomic64_inc: 38 duplicates [...] Each definition is exact equally, e.g.: ffffffff813171b8 <atomic_add>: 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 01 3e lock add %edi,(%rsi) 5d pop %rbp c3 retq In turn each definition has one or more callsites (sure): ffffffff81317c78: e8 3b f5 ff ff callq ffffffff813171b8 <atomic_add> [...] ffffffff8131a062: e8 51 d1 ff ff callq ffffffff813171b8 <atomic_add> [...] ffffffff8131a190: e8 23 d0 ff ff callq ffffffff813171b8 <atomic_add> [...] The other way around would be to remove the static linkage - but I prefer an enforced inlining here. Before: text data bss dec hex filename 81467393 19874720 20168704 121510817 73e1ba1 vmlinux.orig After: text data bss dec hex filename 81461323 19874720 20168704 121504747 73e03eb vmlinux.inlined Yes, the inlining here makes the kernel even smaller! ;) Linus further observed: "I have this memory of having seen that before - the size heuristics for gcc getting confused by inlining. [...] It might be a good idea to mark things that are basically just wrappers around a single (or a couple of) asm instruction to be always_inline." Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1429565231-4609-1-git-send-email-hagen@jauu.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-03locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read()Pranith Kumar
Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile. This is purely a stylistic change. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-14locking,x86: Kill atomic_or_long()Peter Zijlstra
There are no users, kill it. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Jesse Brandeburg <jesse.brandeburg@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20140508135851.768177189@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18arch,x86: Convert smp_mb__*()Peter Zijlstra
x86 is strongly ordered and all its atomic ops imply a full barrier. Implement the two new primitives as the old ones were. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-knswsr5mldkr0w1lrdxvc81w@git.kernel.org Cc: Dave Jones <davej@redhat.com> Cc: Jesse Brandeburg <jesse.brandeburg@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michel Lespinasse <walken@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-12-04x86, bitops: Correct the assembly constraints to testing bitopsH. Peter Anvin
In checkin: 0c44c2d0f459 x86: Use asm goto to implement better modify_and_test() functions the various functions which do modify and test were unified and optimized using "asm goto". However, this change missed the detail that the bitops require an "Ir" constraint rather than an "er" constraint ("I" = integer constant from 0-31, "e" = signed 32-bit integer constant). This would cause code to miscompile if these functions were used on constant bit positions 32-255 and the build to fail if used on constant bit positions above 255. Add the constraints as a parameter to the GEN_BINARY_RMWcc() macro to avoid this problem. Reported-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/529E8719.4070202@zytor.com
2013-09-25x86: Use asm goto to implement better modify_and_test() functionsPeter Zijlstra
Linus suggested using asm goto to get rid of the typical SETcc + TEST instruction pair -- which also clobbers an extra register -- for our typical modify_and_test() functions. Because asm goto doesn't allow output fields it has to include an unconditinal memory clobber when it changes a memory variable to force a reload. Luckily all atomic ops already imply a compiler barrier to go along with their memory barrier semantics. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-0mtn9siwbeo1d33bap1422se@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-11-29x86, 386 removal: Remove CONFIG_XADDH. Peter Anvin
All 486+ CPUs support XADD, so remove the fallback 386 support code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1354132230-21854-4-git-send-email-hpa@linux.intel.com
2012-10-09atomic: implement generic atomic_dec_if_positive()Shaohua Li
The x86 implementation of atomic_dec_if_positive is quite generic, so make it available to all architectures. This is needed for "swap: add a simple detector for inappropriate swapin readahead". [akpm@linux-foundation.org: do the "#define foo foo" trick in the conventional manner] Signed-off-by: Shaohua Li <shli@fusionio.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-02UAPI: (Scripted) Convert #include "..." to #include <path/...> in kernel ↵David Howells
system headers Convert #include "..." to #include <path/...> in kernel system headers. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
2011-08-29x86: Use xadd helper more widelyJeremy Fitzhardinge
This covers the trivial cases from open-coded xadd to the xadd macros. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Link: http://lkml.kernel.org/r/4E5BCC40.3030501@goop.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-26atomic: cleanup asm-generic atomic*.h inclusionArun Sharma
After changing all consumers of atomics to include <linux/atomic.h>, we ran into some compile time errors due to this dependency chain: linux/atomic.h -> asm/atomic.h -> asm-generic/atomic-long.h where atomic-long.h could use funcs defined later in linux/atomic.h without a prototype. This patches moves the code that includes asm-generic/atomic*.h to linux/atomic.h. Archs that need <asm-generic/atomic64.h> need to select CONFIG_GENERIC_ATOMIC64 from now on (some of them used to include it unconditionally). Compile tested on i386 and x86_64 with allnoconfig. Signed-off-by: Arun Sharma <asharma@fb.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26atomic: move atomic_add_unless to generic codeArun Sharma
This is in preparation for more generic atomic primitives based on __atomic_add_unless. Signed-off-by: Arun Sharma <asharma@fb.com> Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26atomic: use <linux/atomic.h>Arun Sharma
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-18Merge branch 'x86-atomic-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-atomic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Fix LOCK_PREFIX_HERE for uniprocessor build x86, atomic64: In selftest, distinguish x86-64 from 586+ x86-32: Fix atomic64_inc_not_zero return value convention lib: Fix atomic64_inc_not_zero test lib: Fix atomic64_add_unless return value convention x86-32: Fix atomic64_add_unless return value convention lib: Fix atomic64_add_unless test x86: Implement atomic[64]_dec_if_positive() lib: Only test atomic64_dec_if_positive on archs having it x86-32: Rewrite 32-bit atomic64 functions in assembly lib: Add self-test for atomic64_t x86-32: Allow UP/SMP lock replacement in cmpxchg64 x86: Add support for lock prefix in alternatives
2010-05-17atomic_t: Cast to volatile when accessing atomic variablesAnton Blanchard
In preparation for removing volatile from the atomic_t definition, this patch adds a volatile cast to all the atomic read functions. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-01x86: Implement atomic[64]_dec_if_positive()Luca Barbieri
Add support for atomic_dec_if_positive(), and atomic64_dec_if_positive() for x86-64. atomic64_dec_if_positive() for x86-32 was already implemented in a previous patch. Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267183361-20775-2-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-16x86: Mark atomic irq ops raw for 32bit legacyIngo Molnar
The atomic ops emulation for 32bit legacy CPUs floods the tracer with irq off/on entries. The irq disabled regions are short and therefor not interesting when chasing long irq disabled latencies. Mark them raw and keep them out of the trace. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-01-07x86: Merge asm/atomic_{32,64}.hBrian Gerst
Merge the now identical code from asm/atomic_32.h and asm/atomic_64.h into asm/atomic.h. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1262883215-4034-4-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: ... and asm-x86 moveAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>