RE: [PATCH] ARC: perf: Accommodate big-endian CPU

From: Alexey Brodkin
Date: Tue Nov 05 2019 - 14:52:24 EST


Hi Sasha, Greg,

> -----Original Message-----
> From: Sasha Levin <sashal@xxxxxxxxxx>
> Sent: Saturday, October 26, 2019 4:11 PM
> To: Sasha Levin <sashal@xxxxxxxxxx>; Alexey Brodkin <abrodkin@xxxxxxxxxxxx>; linux-snps-
> arc@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] ARC: perf: Accommodate big-endian CPU
>
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: all
>
> The bot has tested the following trees: v5.3.7, v4.19.80, v4.14.150, v4.9.197, v4.4.197.
>
> v5.3.7: Build OK!
> v4.19.80: Failed to apply! Possible dependencies:
> 0e956150fe09f ("ARC: perf: introduce Kernel PMU events support")
> 14f81a91ad29a ("ARC: perf: trivial code cleanup")
> baf9cc85ba01f ("ARC: perf: move HW events mapping to separate function")
> v4.14.150: Failed to apply! Possible dependencies:
> v4.9.197: Failed to apply! Possible dependencies:
> v4.4.197: Failed to apply! Possible dependencies:

Indeed the clash is due to
commit baf9cc85ba01f ("ARC: perf: move HW events mapping to separate function") as tmp variable "j" was changed on "i". So that's a fixed hunk:
-------------------------------->8------------------------------
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index 8aec462d90fb..30f66b123541 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -490,8 +490,8 @@ static int arc_pmu_device_probe(struct platform_device *pdev)
/* loop thru all available h/w condition indexes */
for (j = 0; j < cc_bcr.c; j++) {
write_aux_reg(ARC_REG_CC_INDEX, j);
- cc_name.indiv.word0 = read_aux_reg(ARC_REG_CC_NAME0);
- cc_name.indiv.word1 = read_aux_reg(ARC_REG_CC_NAME1);
+ cc_name.indiv.word0 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME0));
+ cc_name.indiv.word1 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME1));

/* See if it has been mapped to a perf event_id */
for (i = 0; i < ARRAY_SIZE(arc_pmu_ev_hw_map); i++) {
-------------------------------->8------------------------------

Should I send a formal patch with it or it's OK for now?

-Alexey