| Message ID | 1529362784-14194-2-git-send-email-leitao@debian.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 96695563cebfb810b09479a9951ebbc466fa4c68 |
| Headers | show |
| Series | [v2,1/4] powerpc/tm: Remove msr_tm_active() | expand |
On Mon, 2018-06-18 at 19:59 -0300, Breno Leitao wrote: > This patch simply fix part of the documentation on the HTM code. > > This fixes reference to old fields that were renamed in commit > 000ec280e3dd ("powerpc: tm: Rename transct_(*) to ck(\1)_state") > > It also documents better the flow after commit eb5c3f1c8647 ("powerpc: > Always save/restore checkpointed regs during treclaim/trecheckpoint"), > where tm_recheckpoint can recheckpoint what is in ck{fp,vr}_state blindly. > > Signed-off-by: Breno Leitao <leitao@debian.org> Acked-By: Michael Neuling <mikey@neuling.org> Thanks > --- > arch/powerpc/kernel/tm.S | 10 +++++----- > arch/powerpc/kernel/traps.c | 15 +++++++++------ > 2 files changed, 14 insertions(+), 11 deletions(-) > > diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S > index ff12f47a96b6..019d73053cd3 100644 > --- a/arch/powerpc/kernel/tm.S > +++ b/arch/powerpc/kernel/tm.S > @@ -95,9 +95,9 @@ EXPORT_SYMBOL_GPL(tm_abort); > * uint8_t cause) > * > * - Performs a full reclaim. This destroys outstanding > - * transactions and updates thread->regs.tm_ckpt_* with the > - * original checkpointed state. Note that thread->regs is > - * unchanged. > + * transactions and updates thread.ckpt_regs, thread.ckfp_state and > + * thread.ckvr_state with the original checkpointed state. Note that > + * thread->regs is unchanged. > * > * Purpose is to both abort transactions of, and preserve the state of, > * a transactions at a context switch. We preserve/restore both sets of > process > @@ -260,7 +260,7 @@ _GLOBAL(tm_reclaim) > > /* Altivec (VEC/VMX/VR)*/ > addi r7, r3, THREAD_CKVRSTATE > - SAVE_32VRS(0, r6, r7) /* r6 scratch, r7 transact vr state */ > + SAVE_32VRS(0, r6, r7) /* r6 scratch, r7 ckvr_state */ > mfvscr v0 > li r6, VRSTATE_VSCR > stvx v0, r7, r6 > @@ -271,7 +271,7 @@ _GLOBAL(tm_reclaim) > > /* Floating Point (FP) */ > addi r7, r3, THREAD_CKFPSTATE > - SAVE_32FPRS_VSRS(0, R6, R7) /* r6 scratch, r7 transact fp state */ > + SAVE_32FPRS_VSRS(0, R6, R7) /* r6 scratch, r7 ckfp_state */ > mffs fr0 > stfd fr0,FPSTATE_FPSCR(r7) > > diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c > index 0e17dcb48720..6742b6b3eb37 100644 > --- a/arch/powerpc/kernel/traps.c > +++ b/arch/powerpc/kernel/traps.c > @@ -1719,16 +1719,19 @@ void fp_unavailable_tm(struct pt_regs *regs) > * checkpointed FP registers need to be loaded. > */ > tm_reclaim_current(TM_CAUSE_FAC_UNAV); > - /* Reclaim didn't save out any FPRs to transact_fprs. */ > + > + /* Reclaim initially saved out bogus (lazy) FPRs to ckfp_state, and > + * then it was overwrite by the thr->fp_state by tm_reclaim_thread(). > + * > + * At this point, ck{fp,vr}_state contains the exact values we want to > + * recheckpoint. > + */ > > /* Enable FP for the task: */ > current->thread.load_fp = 1; > > - /* This loads and recheckpoints the FP registers from > - * thread.fpr[]. They will remain in registers after the > - * checkpoint so we don't need to reload them after. > - * If VMX is in use, the VRs now hold checkpointed values, > - * so we don't want to load the VRs from the thread_struct. > + /* > + * Recheckpoint all the checkpointed ckpt, ck{fp, vr}_state registers. > */ > tm_recheckpoint(¤t->thread); > }
On Mon, 2018-06-18 at 22:59:42 UTC, Breno Leitao wrote: > This patch simply fix part of the documentation on the HTM code. > > This fixes reference to old fields that were renamed in commit > 000ec280e3dd ("powerpc: tm: Rename transct_(*) to ck(\1)_state") > > It also documents better the flow after commit eb5c3f1c8647 ("powerpc: > Always save/restore checkpointed regs during treclaim/trecheckpoint"), > where tm_recheckpoint can recheckpoint what is in ck{fp,vr}_state blindly. > > Signed-off-by: Breno Leitao <leitao@debian.org> > Acked-By: Michael Neuling <mikey@neuling.org> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/96695563cebfb810b09479a9951ebb cheers
diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S index ff12f47a96b6..019d73053cd3 100644 --- a/arch/powerpc/kernel/tm.S +++ b/arch/powerpc/kernel/tm.S @@ -95,9 +95,9 @@ EXPORT_SYMBOL_GPL(tm_abort); * uint8_t cause) * * - Performs a full reclaim. This destroys outstanding - * transactions and updates thread->regs.tm_ckpt_* with the - * original checkpointed state. Note that thread->regs is - * unchanged. + * transactions and updates thread.ckpt_regs, thread.ckfp_state and + * thread.ckvr_state with the original checkpointed state. Note that + * thread->regs is unchanged. * * Purpose is to both abort transactions of, and preserve the state of, * a transactions at a context switch. We preserve/restore both sets of process @@ -260,7 +260,7 @@ _GLOBAL(tm_reclaim) /* Altivec (VEC/VMX/VR)*/ addi r7, r3, THREAD_CKVRSTATE - SAVE_32VRS(0, r6, r7) /* r6 scratch, r7 transact vr state */ + SAVE_32VRS(0, r6, r7) /* r6 scratch, r7 ckvr_state */ mfvscr v0 li r6, VRSTATE_VSCR stvx v0, r7, r6 @@ -271,7 +271,7 @@ _GLOBAL(tm_reclaim) /* Floating Point (FP) */ addi r7, r3, THREAD_CKFPSTATE - SAVE_32FPRS_VSRS(0, R6, R7) /* r6 scratch, r7 transact fp state */ + SAVE_32FPRS_VSRS(0, R6, R7) /* r6 scratch, r7 ckfp_state */ mffs fr0 stfd fr0,FPSTATE_FPSCR(r7) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 0e17dcb48720..6742b6b3eb37 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1719,16 +1719,19 @@ void fp_unavailable_tm(struct pt_regs *regs) * checkpointed FP registers need to be loaded. */ tm_reclaim_current(TM_CAUSE_FAC_UNAV); - /* Reclaim didn't save out any FPRs to transact_fprs. */ + + /* Reclaim initially saved out bogus (lazy) FPRs to ckfp_state, and + * then it was overwrite by the thr->fp_state by tm_reclaim_thread(). + * + * At this point, ck{fp,vr}_state contains the exact values we want to + * recheckpoint. + */ /* Enable FP for the task: */ current->thread.load_fp = 1; - /* This loads and recheckpoints the FP registers from - * thread.fpr[]. They will remain in registers after the - * checkpoint so we don't need to reload them after. - * If VMX is in use, the VRs now hold checkpointed values, - * so we don't want to load the VRs from the thread_struct. + /* + * Recheckpoint all the checkpointed ckpt, ck{fp, vr}_state registers. */ tm_recheckpoint(¤t->thread); }
This patch simply fix part of the documentation on the HTM code. This fixes reference to old fields that were renamed in commit 000ec280e3dd ("powerpc: tm: Rename transct_(*) to ck(\1)_state") It also documents better the flow after commit eb5c3f1c8647 ("powerpc: Always save/restore checkpointed regs during treclaim/trecheckpoint"), where tm_recheckpoint can recheckpoint what is in ck{fp,vr}_state blindly. Signed-off-by: Breno Leitao <leitao@debian.org> --- arch/powerpc/kernel/tm.S | 10 +++++----- arch/powerpc/kernel/traps.c | 15 +++++++++------ 2 files changed, 14 insertions(+), 11 deletions(-)