7401af38db
That returns if the class has a hole greater or equal to the size specified.
Pahole now has a --hole_size_ge command line option to use it.
Example on a linux kernel built for x86_64 where we list the structs that have
holes bigger than 32 bytes, that provides an approximation of structs with
____cacheline_aligned_in_smp annotated members:
[acme@filo pahole]$ pahole --hole_size_ge 32 examples/vmlinux-x86_64
inet_hashinfo
rcu_ctrlblk
hh_cache
net_device
files_struct
module
zone
For instance, look at struct zone clever use of such construct:
_pad1_ is defined with ZONE_PADDING(_pad1_), that is:
/* <40e> /home/acme/git/net-2.6.22/include/linux/mmzone.h:179 */
struct zone {
long unsigned int pages_min; /* 0 8 */
long unsigned int pages_low; /* 8 8 */
long unsigned int pages_high; /* 16 8 */
long unsigned int lowmem_reserve[3]; /* 24 24 */
int node; /* 48 4 */
/* XXX 4 bytes hole, try to pack */
long unsigned int min_unmapped_pages; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
long unsigned int min_slab_pages; /* 64 8 */
struct per_cpu_pageset * pageset[255]; /* 72 2040 */
/* --- cacheline 33 boundary (2112 bytes) --- */
spinlock_t lock; /* 2112 4 */
/* XXX 4 bytes hole, try to pack */
struct free_area free_area[11]; /* 2120 264 */
/* XXX 48 bytes hole, try to pack */
/* --- cacheline 38 boundary (2432 bytes) --- */
struct zone_padding _pad1_; /* 2432 0 */
spinlock_t lru_lock; /* 2432 4 */
/* XXX 4 bytes hole, try to pack */
struct list_head active_list; /* 2440 16 */
struct list_head inactive_list; /* 2456 16 */
long unsigned int nr_scan_active; /* 2472 8 */
long unsigned int nr_scan_inactive; /* 2480 8 */
long unsigned int pages_scanned; /* 2488 8 */
/* --- cacheline 39 boundary (2496 bytes) --- */
int all_unreclaimable; /* 2496 4 */
atomic_t reclaim_in_progress; /* 2500 4 */
atomic_long_t vm_stat[20]; /* 2504 160 */
/* --- cacheline 41 boundary (2624 bytes) was 40 bytes ago --- */
int prev_priority; /* 2664 4 */
/* XXX 20 bytes hole, try to pack */
/* --- cacheline 42 boundary (2688 bytes) --- */
struct zone_padding _pad2_; /* 2688 0 */
wait_queue_head_t * wait_table; /* 2688 8 */
long unsigned int wait_table_hash_nr_entries; /* 2696 8 */
long unsigned int wait_table_bits; /* 2704 8 */
struct pglist_data * zone_pgdat; /* 2712 8 */
long unsigned int zone_start_pfn; /* 2720 8 */
long unsigned int spanned_pages; /* 2728 8 */
long unsigned int present_pages; /* 2736 8 */
const char * name; /* 2744 8 */
/* --- cacheline 43 boundary (2752 bytes) --- */
}; /* size: 2752, cachelines: 43 */
/* sum members: 2672, holes: 5, sum holes: 80 */
/* definitions: 933 */
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
|
||
|---|---|---|
| cmake/modules | ||
| lib | ||
| ostra | ||
| rpm/SPECS | ||
| CMakeLists.txt | ||
| MANIFEST | ||
| README | ||
| README.ctracer | ||
| codiff.c | ||
| ctracer.c | ||
| dtagnames.c | ||
| dwarves.c | ||
| dwarves.h | ||
| dwarves_emit.c | ||
| dwarves_emit.h | ||
| dwarves_reorganize.c | ||
| dwarves_reorganize.h | ||
| list.h | ||
| pahole.c | ||
| pdwtags.c | ||
| pfunct.c | ||
| pglobal.c | ||
| prefcnt.c | ||
README
Build instructions: 1. install cmake 2. mkdir build 3. cd build 4. cmake -D__LIB=lib .. 5. make install Default is to be installed on /usr/local, see rpm spec file for installing on other places. Known to work scenarios: Mandriva Cooker: cmake 2.4.5-1mdv2007.1 libelfutils1-devel 0.123-1mdv2007.1 Debian Unstable: cmake 2.4.5-1 libdw-dev 0.123-2 Fedora Core 6: cmake 2.4.5-2.fc6 elfutils-devel 0.126-1.fc6