/* * arch/alpha/lib/strrchr.S * Contributed by Richard Henderson (rth@tamu.edu) * * Return the address of the last occurrence of a given character * within a null-terminated string, or null if it is not found. */ #include #include .set noreorder .set noat .align 3 .ent strrchr .globl strrchr strrchr: .frame sp, 0, ra .prologue 0 zapnot a1, 1, a1 # e0 : zero extend our test character mov zero, t6 # .. e1 : t6 is last match aligned addr sll a1, 8, t5 # e0 : replicate our test character mov zero, t8 # .. e1 : t8 is last match byte compare mask or t5, a1, a1 # e0 : ldq_u t0, 0(a0) # .. e1 : load first quadword sll a1, 16, t5 # e0 : andnot a0, 7, v0 # .. e1 : align source addr or t5, a1, a1 # e0 : lda t4, -1 # .. e1 : build garbage mask sll a1, 32, t5 # e0 : cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero mskqh t4, a0, t4 # e0 : or t5, a1, a1 # .. e1 : character replication complete xor t0, a1, t2 # e0 : make bytes == c zero cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage cmpbge zero, t2, t3 # e0 : bits set iff byte == c andnot t1, t4, t1 # .. e1 : clear garbage from null test andnot t3, t4, t3 # e0 : clear garbage from char test bne t1, $eos # .. e1 : did we already hit the terminator? /* Character search main loop */ $loop: ldq t0, 8(v0) # e0 : load next quadword cmovne t3, v0, t6 # .. e1 : save previous comparisons match cmovne t3, t3, t8 # e0 : addq v0, 8, v0 # .. e1 : xor t0, a1, t2 # e0 : cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero cmpbge zero, t2, t3 # e0 : bits set iff byte == c beq t1, $loop # .. e1 : if we havnt seen a null, loop /* Mask out character matches after terminator */ $eos: negq t1, t4 # e0 : isolate first null byte match and t1, t4, t4 # e1 : subq t4, 1, t5 # e0 : build a mask of the bytes up to... or t4, t5, t4 # e1 : ... and including the null and t3, t4, t3 # e0 : mask out char matches after null cmovne t3, t3, t8 # .. e1 : save it, if match found cmovne t3, v0, t6 # e0 : /* Locate the address of the last matched character */ /* Retain the early exit for the ev4 -- the ev5 mispredict penalty is 5 cycles -- the same as just falling through. */ beq t8, $retnull # .. e1 : and t8, 0xf0, t2 # e0 : binary search for the high bit set cmovne t2, t2, t8 # .. e1 (zdb) cmovne t2, 4, t2 # e0 : and t8, 0xcc, t1 # .. e1 : cmovne t1, t1, t8 # e0 : cmovne t1, 2, t1 # .. e1 : and t8, 0xaa, t0 # e0 : cmovne t0, 1, t0 # .. e1 (zdb) addq t2, t1, t1 # e0 : addq t6, t0, v0 # .. e1 : add our aligned base ptr to the mix addq v0, t1, v0 # e0 : ret # .. e1 : $retnull: mov zero, v0 # e0 : ret # .. e1 : .end strrchr EXPORT_SYMBOL(strrchr) '10' name='q' value=''/>
path: root/net/ceph/crush/crush.c
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authorThomas Gleixner <tglx@linutronix.de>2017-01-31 09:37:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100
commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /net/ceph/crush/crush.c
parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'net/ceph/crush/crush.c')