On Wednesday 16 January 2008 00:15, Zoltan Menyhart wrote: > Please have a look at the patch below. > > Taking this opportunity, in addition: > - I removed the unnecessary barrier() from __clear_bit_unlock(). > ia64_st4_rel_nta() makes sure all the modifications are globally > seen before the bit is seen to be off. > - I made __clear_bit() modeled after __set_bit() and __change_bit(). > - I corrected some comments sating that a memory barrier is provided, > yet in reality, it is the acquisition side of the memory barrier only. > - I corrected some comments, e.g. test_and_clear_bit() was peaking > about "bit to set". > > Here is the code generated from my and the old versions. > (Though I do not know why "and" is moved in the 2nd bundle.): > > test_new() > { > __clear_bit_unlock(3, &data); > } > > test_old() > { > old__clear_bit_unlock(3, &data); > } > > 0000000000000000 <test_new>: > 0: 02 00 00 00 01 00 [MII] nop.m 0x0 > 6: e0 00 04 00 48 00 addl r14=0,r1;; > c: 00 00 04 00 nop.i 0x0 > 10: 0b 10 00 1c 10 10 [MMI] ld4 r2=[r14];; > 16: f0 b8 0b 58 44 00 and r15=-9,r2 > 1c: 00 00 04 00 nop.i 0x0;; > 20: 0a 00 3c 1c b6 11 [MMI] st4.rel.nta [r14]=r15;; > 26: 00 00 00 02 00 00 nop.m 0x0 > 2c: 01 70 00 84 mov r8=r14 > 30: 1d 00 00 00 01 00 [MFB] nop.m 0x0 > 36: 00 00 00 02 00 80 nop.f 0x0 > 3c: 08 00 84 00 br.ret.sptk.many b0;; > > 0000000000000040 <test_old>: > 40: 02 00 00 00 01 00 [MII] nop.m 0x0 > 46: e0 00 04 00 48 00 addl r14=0,r1;; > 4c: 00 00 04 00 nop.i 0x0 > 50: 03 10 00 1c b0 10 [MII] ld4.acq r2=[r14] > 56: 00 00 00 02 00 e0 nop.i 0x0;; > 5c: 71 17 b0 88 and r15=-9,r2;; > 60: 0a 00 3c 1c b6 11 [MMI] st4.rel.nta [r14]=r15;; > 66: 00 00 00 02 00 00 nop.m 0x0 > 6c: 01 70 00 84 mov r8=r14 > 70: 1d 00 00 00 01 00 [MFB] nop.m 0x0 > 76: 00 00 00 02 00 80 nop.f 0x0 > 7c: 08 00 84 00 br.ret.sptk.many b0;; > > Signed-off-by: Zoltan Menyhart, <Zoltan.Menyhart@xxxxxxxx> I don't see any problem with this patch. FWIW: Acked-by: Nick Piggin <npiggin@xxxxxxx> - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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