| Message ID | 1eb059dcb634c48980e5e43f465aabd3d35ba7f7.1565960416.git.christophe.leroy@c-s.fr (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | powerpc/vdso32: Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch next (c9633332103e55bc73d80d07ead28b95a22a85a3) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 71 lines checked |
On Fri, Aug 16, 2019 at 01:01:50PM +0000, Christophe Leroy wrote: > - add r3,r3,r5 > +78: add r3,r3,r5 You can use actual names for the labels as well... .Lsomething if you want it to stay a local symbol only. Segher
Hi,
Christophe Leroy <christophe.leroy@c-s.fr> writes:
> Benchmark from vdsotest:
I assume you also ran the verification/correctness parts of vdsotest...? :-)
Hi, Le 19/08/2019 à 18:37, Nathan Lynch a écrit : > Hi, > > Christophe Leroy <christophe.leroy@c-s.fr> writes: >> Benchmark from vdsotest: > > I assume you also ran the verification/correctness parts of vdsotest...? :-) > I did run vdsotest-all. I guess it runs the verifications too ? Christophe
Christophe Leroy <christophe.leroy@c-s.fr> writes: > Hi, > > Le 19/08/2019 à 18:37, Nathan Lynch a écrit : >> Hi, >> >> Christophe Leroy <christophe.leroy@c-s.fr> writes: >>> Benchmark from vdsotest: >> >> I assume you also ran the verification/correctness parts of vdsotest...? :-) >> > > I did run vdsotest-all. I guess it runs the verifications too ? It does, but at a quick glance it runs the validation for "only" 1 second per API. It may provide more confidence to allow the validation to run across several second (tv_sec) transitions, e.g. vdsotest -d 30 clock-gettime-monotonic-coarse verify Regardless, I did not see any problem with your patch.
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S index becd9f8767ed..e10098cde89c 100644 --- a/arch/powerpc/kernel/vdso32/gettimeofday.S +++ b/arch/powerpc/kernel/vdso32/gettimeofday.S @@ -71,6 +71,12 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime) cmpli cr0,r3,CLOCK_REALTIME cmpli cr1,r3,CLOCK_MONOTONIC cror cr0*4+eq,cr0*4+eq,cr1*4+eq + + cmpli cr5,r3,CLOCK_REALTIME_COARSE + cmpli cr6,r3,CLOCK_MONOTONIC_COARSE + cror cr5*4+eq,cr5*4+eq,cr6*4+eq + + cror cr0*4+eq,cr0*4+eq,cr5*4+eq bne cr0,99f mflr r12 /* r12 saves lr */ @@ -80,6 +86,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime) mr r9,r3 /* datapage ptr in r9 */ lis r7,NSEC_PER_SEC@h /* want nanoseconds */ ori r7,r7,NSEC_PER_SEC@l + beq cr5,70f 50: bl __do_get_tspec@local /* get sec/nsec from tb & kernel */ bne cr1,80f /* not monotonic -> all done */ @@ -106,12 +113,51 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime) lwz r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9) cmpl cr0,r8,r0 /* check if updated */ bne- 50b + b 78f + + /* + * For coarse clocks we get data directly from the vdso data page, so + * we don't need to call __do_get_tspec, but we still need to do the + * counter trick. + */ +70: lwz r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9) + andi. r0,r8,1 /* pending update ? loop */ + bne- 70b + add r9,r9,r0 /* r0 is already 0 */ + + /* + * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE + * too + */ + lwz r3,STAMP_XTIME+TSPC32_TV_SEC(r9) + lwz r4,STAMP_XTIME+TSPC32_TV_NSEC(r9) + bne cr6,75f + + /* CLOCK_MONOTONIC_COARSE */ + lwz r5,(WTOM_CLOCK_SEC+LOPART)(r9) + lwz r6,WTOM_CLOCK_NSEC(r9) + + /* check if counter has updated */ + or r0,r6,r5 +75: or r0,r0,r3 + or r0,r0,r4 + xor r0,r0,r0 + add r3,r3,r0 + lwz r0,CFG_TB_UPDATE_COUNT+LOPART(r9) + cmpl cr0,r0,r8 /* check if updated */ + bne- 70b + + /* Counter has not updated, so continue calculating proper values for + * sec and nsec if monotonic coarse, or just return with the proper + * values for realtime. + */ + bne cr6,80f /* Calculate and store result. Note that this mimics the C code, * which may cause funny results if nsec goes negative... is that * possible at all ? */ - add r3,r3,r5 +78: add r3,r3,r5 add r4,r4,r6 cmpw cr0,r4,r7 cmpwi cr1,r4,0
This is copied and adapted from commit 5c929885f1bb ("powerpc/vdso64: Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE") from Santosh Sivaraj <santosh@fossix.org> Benchmark from vdsotest: clock-gettime-realtime: syscall: 3601 nsec/call clock-gettime-realtime: libc: 1072 nsec/call clock-gettime-realtime: vdso: 931 nsec/call clock-gettime-monotonic: syscall: 4034 nsec/call clock-gettime-monotonic: libc: 1213 nsec/call clock-gettime-monotonic: vdso: 1076 nsec/call clock-gettime-realtime-coarse: syscall: 2722 nsec/call clock-gettime-realtime-coarse: libc: 805 nsec/call clock-gettime-realtime-coarse: vdso: 668 nsec/call clock-gettime-monotonic-coarse: syscall: 2949 nsec/call clock-gettime-monotonic-coarse: libc: 882 nsec/call clock-gettime-monotonic-coarse: vdso: 745 nsec/call Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Santosh Sivaraj <santosh@fossix.org> Link: https://github.com/linuxppc/issues/issues/41 --- arch/powerpc/kernel/vdso32/gettimeofday.S | 48 ++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-)