[PATCH v2] RecipeCommon: IRQ: check if MSI interrupt is registered

[Jan Tluka]

This is a fix for an issue we hit on specific NIC tracked in
https://bugzilla.redhat.com/show_bug.cgi?id=1484059

In this case the mlx4_core driver lists all available MSI interrupts
under /sys/class/$dev/device/msi_irqs, this covers interrupts for both
mlx4_en (network part) and mlx4_ib (storage part) even if any of these is
not loaded yet. The IRQs are propagated to /proc/irq/ directory once
they're loaded.

To fix this the availability of the interrupt id is first checked in
/proc/irq/ directory and modified only if present.

v2: I moved the /proc/irq listing out of the loop so that the command is
    run just once and reused when checking the presence of specific IRQ
    number

Signed-off-by: Jan Tluka 
---
 lnst/RecipeCommon/IRQ.py | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/lnst/RecipeCommon/IRQ.py b/lnst/RecipeCommon/IRQ.py
index 88d673b..f61f23c 100644
--- a/lnst/RecipeCommon/IRQ.py
+++ b/lnst/RecipeCommon/IRQ.py
@@ -11,6 +11,7 @@ __author__ = """
 [e-mail] (Jan Tluka)
 """

+import re

'''
 Pins all device IRQs to specified cpu on machine.
@@ -33,9 +34,22 @@ def pin_dev_irqs(machine, device, cpu):
         res = pi.get_result()
         intrs = res["res_data"]["stdout"]

+    # save all /proc/irq/ entries
+    cmd = machine.run("ls -1 /proc/irq/ 2>/dev/null || true")
+    res = cmd.get_result()
+    proc_irq = res["res_data"]["stdout"]
+
     for intr in intrs.split('\n'):
         try:
             int(intr)
         except:
             continue
-        machine.config("/proc/irq/%s/smp_affinity_list" % intr.strip(), cpu)
+
+        # some drivers list all _available_ MSI interrupts under msi_irqs
+        # even for driver parts that are not loaded (in case of converged
+        # network adapters) and these interrupts are not visible under
+        # /proc/irq and make LNST report failure so we need to check if the
+        # interrupt is available first
+
+        if re.search("^%s$" % intr.strip(), proc_irq, re.MULTILINE) is not None:
+            machine.config("/proc/irq/%s/smp_affinity_list" % intr.strip(), cpu)

[Jan Tluka]

Mon, Oct 08, 2018 at 02:34:31PM CEST, [e-mail] wrote:
> This is a fix for an issue we hit on specific NIC tracked in
> https://bugzilla.redhat.com/show_bug.cgi?id=1484059
>
> In this case the mlx4_core driver lists all available MSI interrupts
> under /sys/class/$dev/device/msi_irqs, this covers interrupts for both
> mlx4_en (network part) and mlx4_ib (storage part) even if any of these is
> not loaded yet. The IRQs are propagated to /proc/irq/ directory once
> they're loaded.
>
> To fix this the availability of the interrupt id is first checked in
> /proc/irq/ directory and modified only if present.
>
> v2: I moved the /proc/irq listing out of the loop so that the command is
>    run just once and reused when checking the presence of specific IRQ
>    number
>
> Signed-off-by: Jan Tluka

I pushed this one.

-Jan