[PATCH AUTOSEL 6.2 43/45] tools/power turbostat: Fix /dev/cpu_dma_latency warnings

[PATCH AUTOSEL 6.2 43/45] tools/power turbostat: Fix /dev/cpu_dma_latency warnings

[Sasha Levin]

From: Prarit Bhargava <prarit@redhat.com>

[ Upstream commit 40aafc7d58d3544f152a863a0e9863014b6d5d8c ]

When running as non-root the following error is seen in turbostat:

turbostat: fopen /dev/cpu_dma_latency
: Permission denied

turbostat and the man page have information on how to avoid other
permission errors, so these can be fixed the same way.

Provide better /dev/cpu_dma_latency warnings that provide instructions on
how to avoid the error, and update the man page.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/power/x86/turbostat/turbostat.8 | 2 ++
 tools/power/x86/turbostat/turbostat.c | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.8 b/tools/power/x86/turbostat/turbostat.8
index c7b26a3603afe..3e1a4c4be001a 100644
--- a/tools/power/x86/turbostat/turbostat.8
+++ b/tools/power/x86/turbostat/turbostat.8
@@ -344,6 +344,8 @@ Alternatively, non-root users can be enabled to run turbostat this way:
 
 # chmod +r /dev/cpu/*/msr
 
+# chmod +r /dev/cpu_dma_latency
+
 .B "turbostat "
 reads hardware counters, but doesn't write them.
 So it will not interfere with the OS or other programs, including
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index aba460410dbd1..c24054e3ef7ad 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -5482,7 +5482,7 @@ void print_dev_latency(void)
 
 	retval = read(fd, (void *)&value, sizeof(int));
 	if (retval != sizeof(int)) {
-		warn("read %s\n", path);
+		warn("read failed %s\n", path);
 		close(fd);
 		return;
 	}
-- 
2.39.2

[PATCH AUTOSEL 6.2 44/45] tools/power turbostat: fix decoding of HWP_STATUS

[Sasha Levin]

From: Antti Laakso <antti.laakso@intel.com>

[ Upstream commit 92c25393586ac799b9b7d9e50434f3c44a7622c4 ]

The "excursion to minimum" information is in bit2
in HWP_STATUS MSR. Fix the bitmask used for
decoding the register.

Signed-off-by: Antti Laakso <antti.laakso@intel.com>
Reviewed-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/power/x86/turbostat/turbostat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index c24054e3ef7ad..c61c6c704fbe6 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -4426,7 +4426,7 @@ int print_hwp(struct thread_data *t, struct core_data *c, struct pkg_data *p)
 
 	fprintf(outf, "cpu%d: MSR_HWP_STATUS: 0x%08llx "
 		"(%sGuaranteed_Perf_Change, %sExcursion_Min)\n",
-		cpu, msr, ((msr) & 0x1) ? "" : "No-", ((msr) & 0x2) ? "" : "No-");
+		cpu, msr, ((msr) & 0x1) ? "" : "No-", ((msr) & 0x4) ? "" : "No-");
 
 	return 0;
 }
-- 
2.39.2