diff options
| author | Breno Leitao <leitao@debian.org> | 2018-06-18 19:59:42 -0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-09-17 21:17:25 +1000 |
| commit | 96695563cebfb810b09479a9951ebbc466fa4c68 (patch) | |
| tree | cafe4cd12de4df63d9a8f56f9fbcdfeb67ce4c77 /arch | |
| parent | 693b31b2fc1636f0aa7af53136d3b49f6ad9ff39 (diff) | |
powerpc/tm: Fix HTM documentation
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>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/tm.S | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 16 |
2 files changed, 15 insertions, 11 deletions
diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S index 6bffbc5affe7..50e5cff10d0f 100644 --- a/arch/powerpc/kernel/tm.S +++ b/arch/powerpc/kernel/tm.S @@ -96,9 +96,9 @@ 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 @@ -261,7 +261,7 @@ _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 @@ -272,7 +272,7 @@ _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 c85adb858271..6ab66a88db14 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1750,16 +1750,20 @@ 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); } |