UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

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
000ec280e3 ("powerpc: tm: Rename transct_(*) to ck(\1)_state")

It also documents better the flow after commit eb5c3f1c86 ("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>
This commit is contained in:
Breno Leitao 2018-06-18 19:59:42 -03:00 committed by Michael Ellerman
parent 693b31b2fc
commit 96695563ce
2 changed files with 15 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/powerpc/kernel/tm.S
View File

@ -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)

16
arch/powerpc/kernel/traps.c
View File

@ -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(&current->thread);
}