Re: [PATCH v3 01/14] KVM: s390: pv: add macros for UVC CC values
From: Janosch Frank <frankja@linux.ibm.com>
Date: 2021-08-06 15:15:57
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On 8/6/21 9:26 AM, David Hildenbrand wrote:
On 04.08.21 17:40, Claudio Imbrenda wrote:quoted
Add macros to describe the 4 possible CC values returned by the UVC instruction. Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> --- arch/s390/include/asm/uv.h | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index 12c5f006c136..b35add51b967 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h@@ -18,6 +18,11 @@ #include <asm/page.h> #include <asm/gmap.h> +#define UVC_CC_OK 0 +#define UVC_CC_ERROR 1 +#define UVC_CC_BUSY 2 +#define UVC_CC_PARTIAL 3 + #define UVC_RC_EXECUTED 0x0001 #define UVC_RC_INV_CMD 0x0002 #define UVC_RC_INV_STATE 0x0003Do we have any users we could directly fix up? AFAIKs, most users don't really care about the cc value, only about cc vs !cc. The only instances I was able to spot quickly:
The only fix for the functions below that I would accept would be to check for cc 2 and 3. A cc >= UVC_CC_BUSY confuses me way too much when reading. But honestly for those two I'd just keep the code as is. I only asked Claudio to fix the code in the next patch and add this patch as it was not clearly visible he was dealing with a CC.
quoted hunk ↗ jump to hunk
diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index 12c5f006c136..dd72d325f9e8 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h@@ -233,7 +233,7 @@ static inline int uv_call(unsigned long r1, unsignedlong r2) do { cc = __uv_call(r1, r2); - } while (cc > 1); + } while (cc >= UVC_CC_BUSY); return cc; }@@ -245,7 +245,7 @@ static inline int uv_call_sched(unsigned long r1,unsigned long r2) do { cc = __uv_call(r1, r2); cond_resched(); - } while (cc > 1); + } while (cc >= UVC_CC_BUSY); return cc; } Of course, we could replace all checks for cc vs !cc with "cc != UVC_CC_OK" vs "cc == UVC_CC_OK".