Add stats support for EC2 local storage instance type

[lingkai0110]

This patch is a follow up of (#2559).

It adds the stats support for EC2 local storage on top of EBS.

For local stroage, it supports a --details / -d option. In this mode it will print out detail io histograms for different block size ranges.

[igaw]

Could you tweak the commit message slightly. Use a prefix for the commit title, e.g.

plugins/amzn: ...

Also the link to github in the first sentence should be removed. The simple reason is that we don't want to tight in this platform, so every commit message should be complete in itself. Pointer to external sources is sometimes okay, but usually those links have a limited life time. I think you can just remove the first sentence.

[igaw]

 /usr/bin/arm-linux-gnueabihf-gcc -Invme.p -I. -I.. -Iccan -I../ccan -Isubprojects/libnvme/src -I../subprojects/libnvme/src -fdiagnostics-color=always -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Werror -std=gnu99 -O3 -fomit-frame-pointer -D_GNU_SOURCE -include config.h -MD -MQ nvme.p/plugins_amzn_amzn-nvme.c.o -MF nvme.p/plugins_amzn_amzn-nvme.c.o.d -o nvme.p/plugins_amzn_amzn-nvme.c.o -c ../plugins/amzn/amzn-nvme.c
../plugins/amzn/amzn-nvme.c: In function ‘get_stats’:
../plugins/amzn/amzn-nvme.c:538:51: error: macro "amzn_print_json_stats" passed 2 arguments, but takes just 1
  538 |                 amzn_print_json_stats(&log, detail);
      |                                                   ^
../plugins/amzn/amzn-nvme.c:455: note: macro "amzn_print_json_stats" defined here
  455 | #define amzn_print_json_stats(log)
      | 
../plugins/amzn/amzn-nvme.c:538:17: error: ‘amzn_print_json_stats’ undeclared (first use in this function); did you mean ‘amzn_print_io_stats’?
  538 |                 amzn_print_json_stats(&log, detail);
      |                 ^~~~~~~~~~~~~~~~~~~~~
      |                 amzn_print_io_stats

[lingkai0110]

Thanks. Will look into those suggestions.

[lingkai0110]

@igaw Thanks for the review. I’ve addressed your feedback in 9e86225:

• Commit title now uses the plugins/amzn: prefix and I removed the external link from the message body.
• Fixed the amzn_print_json_stats call/signature mismatch and cleaned up JSON/plain output paths.
• Fixed the format checking
• Fresh build is clean on GCC and Clang:
meson setup .build && meson compile -C .build

[lingkai0110]

@igaw Thanks for the review. I’ve addressed your feedback in 9e86225:

• Commit title now uses the plugins/amzn: prefix and I removed the external link from the message body.
• Fixed the amzn_print_json_stats call/signature mismatch and cleaned up JSON/plain output paths.
• Fixed the format checking
• Fresh build is clean on GCC and Clang:
meson setup .build && meson compile -C .build

Please have a look. Thanks again.

[igaw]

I've fixed a few of the checkpatch warnings, e.g. overlong lines. If a line gets too long because of the intention, it usually a sign, that the function should be splitted into smaller blocks.

Thanks!