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-rw-r--r--Documentation/filesystems/proc.txt30
-rw-r--r--Documentation/kernel-parameters.txt2
2 files changed, 31 insertions, 1 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 4a37e25e694c..e5c1df52a876 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -347,7 +347,35 @@ connects the CPUs in a SMP system. This means that an error has been detected,
347the IO-APIC automatically retry the transmission, so it should not be a big 347the IO-APIC automatically retry the transmission, so it should not be a big
348problem, but you should read the SMP-FAQ. 348problem, but you should read the SMP-FAQ.
349 349
350In this context it could be interesting to note the new irq directory in 2.4. 350In 2.6.2* /proc/interrupts was expanded again. This time the goal was for
351/proc/interrupts to display every IRQ vector in use by the system, not
352just those considered 'most important'. The new vectors are:
353
354 THR -- interrupt raised when a machine check threshold counter
355 (typically counting ECC corrected errors of memory or cache) exceeds
356 a configurable threshold. Only available on some systems.
357
358 TRM -- a thermal event interrupt occurs when a temperature threshold
359 has been exceeded for the CPU. This interrupt may also be generated
360 when the temperature drops back to normal.
361
362 SPU -- a spurious interrupt is some interrupt that was raised then lowered
363 by some IO device before it could be fully processed by the APIC. Hence
364 the APIC sees the interrupt but does not know what device it came from.
365 For this case the APIC will generate the interrupt with a IRQ vector
366 of 0xff. This might also be generated by chipset bugs.
367
368 RES, CAL, TLB -- rescheduling, call and TLB flush interrupts are
369 sent from one CPU to another per the needs of the OS. Typically,
370 their statistics are used by kernel developers and interested users to
371 determine the occurance of interrupt of the given type.
372
373The above IRQ vectors are displayed only when relevent. For example,
374the threshold vector does not exist on x86_64 platforms. Others are
375suppressed when the system is a uniprocessor. As of this writing, only
376i386 and x86_64 platforms support the new IRQ vector displays.
377
378Of some interest is the introduction of the /proc/irq directory to 2.4.
351It could be used to set IRQ to CPU affinity, this means that you can "hook" an 379It could be used to set IRQ to CPU affinity, this means that you can "hook" an
352IRQ to only one CPU, or to exclude a CPU of handling IRQs. The contents of the 380IRQ to only one CPU, or to exclude a CPU of handling IRQs. The contents of the
353irq subdir is one subdir for each IRQ, and one file; prof_cpu_mask 381irq subdir is one subdir for each IRQ, and one file; prof_cpu_mask
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 63bda3637085..98cf90f2631d 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -994,6 +994,8 @@ and is between 256 and 4096 characters. It is defined in the file
994 994
995 mce [X86-32] Machine Check Exception 995 mce [X86-32] Machine Check Exception
996 996
997 mce=option [X86-64] See Documentation/x86_64/boot-options.txt
998
997 md= [HW] RAID subsystems devices and level 999 md= [HW] RAID subsystems devices and level
998 See Documentation/md.txt. 1000 See Documentation/md.txt.
999 1001