emo/procps
1
0
Fork 0
Code Issues Pull Requests Packages Releases Activity
518358dd50
procps/proc/meminfo.c
Jim Warner 9bea1b2def library: the overlooked twerks (oops, tweaks), 3rd gen 
Yes, all of these changes are strictly cosmetic. It is
likely symptomatic of some deep-seated character flaw.

[ or, it might be because of a certain pride in this ]
[ new library and the desire to make it even better! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-07-09 12:48:28 +10:00

848 lines
26 KiB
C
Raw Blame History

/*
* libprocps - Library to read proc filesystem
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <errno.h>
#include <fcntl.h>
#include <search.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <proc/procps-private.h>
#include <proc/meminfo.h>
#define MEMINFO_FILE "/proc/meminfo"
struct meminfo_data {
unsigned long Active;
unsigned long Active_anon; // as: Active(anon):
unsigned long Active_file; // as: Active(file):
unsigned long AnonHugePages;
unsigned long AnonPages;
unsigned long Bounce;
unsigned long Buffers;
unsigned long Cached;
unsigned long CmaFree; // man 5 proc: 'to be documented'
unsigned long CmaTotal; // man 5 proc: 'to be documented'
unsigned long CommitLimit;
unsigned long Committed_AS;
unsigned long DirectMap1G; // man 5 proc: 'to be documented'
unsigned long DirectMap2M; // man 5 proc: 'to be documented'
unsigned long DirectMap4k; // man 5 proc: 'to be documented'
unsigned long Dirty;
unsigned long HardwareCorrupted;
unsigned long HighFree;
unsigned long HighTotal;
unsigned long HugePages_Free;
unsigned long HugePages_Rsvd;
unsigned long HugePages_Surp;
unsigned long HugePages_Total;
unsigned long Hugepagesize;
unsigned long Inactive;
unsigned long Inactive_anon; // as: Inactive(anon):
unsigned long Inactive_file; // as: Inactive(file):
unsigned long KernelStack;
unsigned long LowFree;
unsigned long LowTotal;
unsigned long Mapped;
unsigned long MemAvailable;
unsigned long MemFree;
unsigned long MemTotal;
unsigned long Mlocked;
unsigned long NFS_Unstable;
unsigned long PageTables;
unsigned long SReclaimable;
unsigned long SUnreclaim;
unsigned long Shmem;
unsigned long Slab;
unsigned long SwapCached;
unsigned long SwapFree;
unsigned long SwapTotal;
unsigned long Unevictable;
unsigned long VmallocChunk;
unsigned long VmallocTotal;
unsigned long VmallocUsed;
unsigned long Writeback;
unsigned long WritebackTmp;
unsigned long derived_mem_hi_used;
unsigned long derived_mem_lo_used;
unsigned long derived_mem_used;
unsigned long derived_swap_used;
};
struct mem_hist {
struct meminfo_data new;
struct meminfo_data old;
};
struct stacks_extent {
int ext_numstacks;
struct stacks_extent *next;
struct meminfo_stack **stacks;
};
struct procps_meminfo {
int refcount;
int meminfo_fd;
int meminfo_was_read;
int dirty_stacks;
struct mem_hist hist;
int numitems;
enum meminfo_item *items;
struct stacks_extent *extents;
struct hsearch_data hashtab;
struct meminfo_result get_this;
};
// ___ Results 'Set' Support ||||||||||||||||||||||||||||||||||||||||||||||||||
#define setNAME(e) set_results_ ## e
#define setDECL(e) static void setNAME(e) \
(struct meminfo_result *R, struct mem_hist *H)
// regular assignment
#define MEM_set(e,t,x) setDECL(e) { R->result. t = H->new . x; }
// delta assignment
#define HST_set(e,t,x) setDECL(e) { R->result. t = ( H->new . x - H->old. x ); }
setDECL(noop) { (void)R; (void)H; }
setDECL(extra) { (void)R; (void)H; }
MEM_set(MEM_ACTIVE, ul_int, Active)
MEM_set(MEM_ACTIVE_ANON, ul_int, Active_anon)
MEM_set(MEM_ACTIVE_FILE, ul_int, Active_file)
MEM_set(MEM_ANON, ul_int, AnonPages)
MEM_set(MEM_AVAILABLE, ul_int, MemAvailable)
MEM_set(MEM_BOUNCE, ul_int, Bounce)
MEM_set(MEM_BUFFERS, ul_int, Buffers)
MEM_set(MEM_CACHED, ul_int, Cached)
MEM_set(MEM_COMMIT_LIMIT, ul_int, CommitLimit)
MEM_set(MEM_COMMITTED_AS, ul_int, Committed_AS)
MEM_set(MEM_HARD_CORRUPTED, ul_int, HardwareCorrupted)
MEM_set(MEM_DIRTY, ul_int, Dirty)
MEM_set(MEM_FREE, ul_int, MemFree)
MEM_set(MEM_HUGE_ANON, ul_int, AnonHugePages)
MEM_set(MEM_HUGE_FREE, ul_int, HugePages_Free)
MEM_set(MEM_HUGE_RSVD, ul_int, HugePages_Rsvd)
MEM_set(MEM_HUGE_SIZE, ul_int, Hugepagesize)
MEM_set(MEM_HUGE_SURPLUS, ul_int, HugePages_Surp)
MEM_set(MEM_HUGE_TOTAL, ul_int, HugePages_Total)
MEM_set(MEM_INACTIVE, ul_int, Inactive)
MEM_set(MEM_INACTIVE_ANON, ul_int, Inactive_anon)
MEM_set(MEM_INACTIVE_FILE, ul_int, Inactive_file)
MEM_set(MEM_KERNEL_STACK, ul_int, KernelStack)
MEM_set(MEM_LOCKED, ul_int, Mlocked)
MEM_set(MEM_MAPPED, ul_int, Mapped)
MEM_set(MEM_NFS_UNSTABLE, ul_int, NFS_Unstable)
MEM_set(MEM_PAGE_TABLES, ul_int, PageTables)
MEM_set(MEM_SHARED, ul_int, Shmem)
MEM_set(MEM_SLAB, ul_int, Slab)
MEM_set(MEM_SLAB_RECLAIM, ul_int, SReclaimable)
MEM_set(MEM_SLAB_UNRECLAIM, ul_int, SUnreclaim)
MEM_set(MEM_TOTAL, ul_int, MemTotal)
MEM_set(MEM_UNEVICTABLE, ul_int, Unevictable)
MEM_set(MEM_USED, ul_int, derived_mem_used)
MEM_set(MEM_VM_ALLOC_CHUNK, ul_int, VmallocChunk)
MEM_set(MEM_VM_ALLOC_TOTAL, ul_int, VmallocTotal)
MEM_set(MEM_VM_ALLOC_USED, ul_int, VmallocUsed)
MEM_set(MEM_WRITEBACK, ul_int, Writeback)
MEM_set(MEM_WRITEBACK_TMP, ul_int, WritebackTmp)
HST_set(DELTA_ACTIVE, s_int, Active)
HST_set(DELTA_ACTIVE_ANON, s_int, Active_anon)
HST_set(DELTA_ACTIVE_FILE, s_int, Active_file)
HST_set(DELTA_ANON, s_int, AnonPages)
HST_set(DELTA_AVAILABLE, s_int, MemAvailable)
HST_set(DELTA_BOUNCE, s_int, Bounce)
HST_set(DELTA_BUFFERS, s_int, Buffers)
HST_set(DELTA_CACHED, s_int, Cached)
HST_set(DELTA_COMMIT_LIMIT, s_int, CommitLimit)
HST_set(DELTA_COMMITTED_AS, s_int, Committed_AS)
HST_set(DELTA_HARD_CORRUPTED, s_int, HardwareCorrupted)
HST_set(DELTA_DIRTY, s_int, Dirty)
HST_set(DELTA_FREE, s_int, MemFree)
HST_set(DELTA_HUGE_ANON, s_int, AnonHugePages)
HST_set(DELTA_HUGE_FREE, s_int, HugePages_Free)
HST_set(DELTA_HUGE_RSVD, s_int, HugePages_Rsvd)
HST_set(DELTA_HUGE_SIZE, s_int, Hugepagesize)
HST_set(DELTA_HUGE_SURPLUS, s_int, HugePages_Surp)
HST_set(DELTA_HUGE_TOTAL, s_int, HugePages_Total)
HST_set(DELTA_INACTIVE, s_int, Inactive)
HST_set(DELTA_INACTIVE_ANON, s_int, Inactive_anon)
HST_set(DELTA_INACTIVE_FILE, s_int, Inactive_file)
HST_set(DELTA_KERNEL_STACK, s_int, KernelStack)
HST_set(DELTA_LOCKED, s_int, Mlocked)
HST_set(DELTA_MAPPED, s_int, Mapped)
HST_set(DELTA_NFS_UNSTABLE, s_int, NFS_Unstable)
HST_set(DELTA_PAGE_TABLES, s_int, PageTables)
HST_set(DELTA_SHARED, s_int, Shmem)
HST_set(DELTA_SLAB, s_int, Slab)
HST_set(DELTA_SLAB_RECLAIM, s_int, SReclaimable)
HST_set(DELTA_SLAB_UNRECLAIM, s_int, SUnreclaim)
HST_set(DELTA_TOTAL, s_int, MemTotal)
HST_set(DELTA_UNEVICTABLE, s_int, Unevictable)
HST_set(DELTA_USED, s_int, derived_mem_used)
HST_set(DELTA_VM_ALLOC_CHUNK, s_int, VmallocChunk)
HST_set(DELTA_VM_ALLOC_TOTAL, s_int, VmallocTotal)
HST_set(DELTA_VM_ALLOC_USED, s_int, VmallocUsed)
HST_set(DELTA_WRITEBACK, s_int, Writeback)
HST_set(DELTA_WRITEBACK_TMP, s_int, WritebackTmp)
MEM_set(MEMHI_FREE, ul_int, HighFree)
MEM_set(MEMHI_TOTAL, ul_int, HighTotal)
MEM_set(MEMHI_USED, ul_int, derived_mem_hi_used)
MEM_set(MEMLO_FREE, ul_int, LowFree)
MEM_set(MEMLO_TOTAL, ul_int, LowTotal)
MEM_set(MEMLO_USED, ul_int, derived_mem_lo_used)
MEM_set(SWAP_CACHED, ul_int, SwapCached)
MEM_set(SWAP_FREE, ul_int, SwapFree)
MEM_set(SWAP_TOTAL, ul_int, SwapTotal)
MEM_set(SWAP_USED, ul_int, derived_swap_used)
#undef setDECL
#undef MEM_set
#undef HST_set
// ___ Controlling Table ||||||||||||||||||||||||||||||||||||||||||||||||||||||
typedef void (*SET_t)(struct meminfo_result *, struct mem_hist *);
#define RS(e) (SET_t)setNAME(e)
/*
* Need it be said?
* This table must be kept in the exact same order as
* those 'enum meminfo_item' guys ! */
static struct {
SET_t setsfunc; // the actual result setting routine
} Item_table[] = {
/* setsfunc
-------------------------- */
{ RS(noop) },
{ RS(extra) },
{ RS(MEM_ACTIVE) },
{ RS(MEM_ACTIVE_ANON) },
{ RS(MEM_ACTIVE_FILE) },
{ RS(MEM_ANON) },
{ RS(MEM_AVAILABLE) },
{ RS(MEM_BOUNCE) },
{ RS(MEM_BUFFERS) },
{ RS(MEM_CACHED) },
{ RS(MEM_COMMIT_LIMIT) },
{ RS(MEM_COMMITTED_AS) },
{ RS(MEM_HARD_CORRUPTED) },
{ RS(MEM_DIRTY) },
{ RS(MEM_FREE) },
{ RS(MEM_HUGE_ANON) },
{ RS(MEM_HUGE_FREE) },
{ RS(MEM_HUGE_RSVD) },
{ RS(MEM_HUGE_SIZE) },
{ RS(MEM_HUGE_SURPLUS) },
{ RS(MEM_HUGE_TOTAL) },
{ RS(MEM_INACTIVE) },
{ RS(MEM_INACTIVE_ANON) },
{ RS(MEM_INACTIVE_FILE) },
{ RS(MEM_KERNEL_STACK) },
{ RS(MEM_LOCKED) },
{ RS(MEM_MAPPED) },
{ RS(MEM_NFS_UNSTABLE) },
{ RS(MEM_PAGE_TABLES) },
{ RS(MEM_SHARED) },
{ RS(MEM_SLAB) },
{ RS(MEM_SLAB_RECLAIM) },
{ RS(MEM_SLAB_UNRECLAIM) },
{ RS(MEM_TOTAL) },
{ RS(MEM_UNEVICTABLE) },
{ RS(MEM_USED) },
{ RS(MEM_VM_ALLOC_CHUNK) },
{ RS(MEM_VM_ALLOC_TOTAL) },
{ RS(MEM_VM_ALLOC_USED) },
{ RS(MEM_WRITEBACK) },
{ RS(MEM_WRITEBACK_TMP) },
{ RS(DELTA_ACTIVE) },
{ RS(DELTA_ACTIVE_ANON) },
{ RS(DELTA_ACTIVE_FILE) },
{ RS(DELTA_ANON) },
{ RS(DELTA_AVAILABLE) },
{ RS(DELTA_BOUNCE) },
{ RS(DELTA_BUFFERS) },
{ RS(DELTA_CACHED) },
{ RS(DELTA_COMMIT_LIMIT) },
{ RS(DELTA_COMMITTED_AS) },
{ RS(DELTA_HARD_CORRUPTED) },
{ RS(DELTA_DIRTY) },
{ RS(DELTA_FREE) },
{ RS(DELTA_HUGE_ANON) },
{ RS(DELTA_HUGE_FREE) },
{ RS(DELTA_HUGE_RSVD) },
{ RS(DELTA_HUGE_SIZE) },
{ RS(DELTA_HUGE_SURPLUS) },
{ RS(DELTA_HUGE_TOTAL) },
{ RS(DELTA_INACTIVE) },
{ RS(DELTA_INACTIVE_ANON) },
{ RS(DELTA_INACTIVE_FILE) },
{ RS(DELTA_KERNEL_STACK) },
{ RS(DELTA_LOCKED) },
{ RS(DELTA_MAPPED) },
{ RS(DELTA_NFS_UNSTABLE) },
{ RS(DELTA_PAGE_TABLES) },
{ RS(DELTA_SHARED) },
{ RS(DELTA_SLAB) },
{ RS(DELTA_SLAB_RECLAIM) },
{ RS(DELTA_SLAB_UNRECLAIM) },
{ RS(DELTA_TOTAL) },
{ RS(DELTA_UNEVICTABLE) },
{ RS(DELTA_USED) },
{ RS(DELTA_VM_ALLOC_CHUNK) },
{ RS(DELTA_VM_ALLOC_TOTAL) },
{ RS(DELTA_VM_ALLOC_USED) },
{ RS(DELTA_WRITEBACK) },
{ RS(DELTA_WRITEBACK_TMP) },
{ RS(MEMHI_FREE) },
{ RS(MEMHI_TOTAL) },
{ RS(MEMHI_USED) },
{ RS(MEMLO_FREE) },
{ RS(MEMLO_TOTAL) },
{ RS(MEMLO_USED) },
{ RS(SWAP_CACHED) },
{ RS(SWAP_FREE) },
{ RS(SWAP_TOTAL) },
{ RS(SWAP_USED) },
// dummy entry corresponding to PROCPS_MEMINFO_logical_end ...
{ NULL, }
};
/* please note,
* this enum MUST be 1 greater than the highest value of any enum */
enum meminfo_item PROCPS_MEMINFO_logical_end = PROCPS_MEMINFO_SWAP_USED + 1;
#undef setNAME
#undef RS
// ___ Private Functions ||||||||||||||||||||||||||||||||||||||||||||||||||||||
static inline void assign_results (
struct meminfo_stack *stack,
struct mem_hist *hist)
{
struct meminfo_result *this = stack->head;
for (;;) {
enum meminfo_item item = this->item;
if (item >= PROCPS_MEMINFO_logical_end)
break;
Item_table[item].setsfunc(this, hist);
++this;
}
return;
} // end: assign_results
static inline void cleanup_stack (
struct meminfo_result *this)
{
for (;;) {
if (this->item >= PROCPS_MEMINFO_logical_end)
break;
if (this->item > PROCPS_MEMINFO_noop)
this->result.ul_int = 0;
++this;
}
} // end: cleanup_stack
static inline void cleanup_stacks_all (
struct procps_meminfo *info)
{
struct stacks_extent *ext = info->extents;
int i;
while (ext) {
for (i = 0; ext->stacks[i]; i++)
cleanup_stack(ext->stacks[i]->head);
ext = ext->next;
};
info->dirty_stacks = 0;
} // end: cleanup_stacks_all
static void extents_free_all (
struct procps_meminfo *info)
{
while (info->extents) {
struct stacks_extent *p = info->extents;
info->extents = info->extents->next;
free(p);
};
} // end: extents_free_all
static inline struct meminfo_result *itemize_stack (
struct meminfo_result *p,
int depth,
enum meminfo_item *items)
{
struct meminfo_result *p_sav = p;
int i;
for (i = 0; i < depth; i++) {
p->item = items[i];
p->result.ul_int = 0;
++p;
}
return p_sav;
} // end: itemize_stack
static inline int items_check_failed (
int numitems,
enum meminfo_item *items)
{
int i;
/* if an enum is passed instead of an address of one or more enums, ol' gcc
* will silently convert it to an address (possibly NULL). only clang will
* offer any sort of warning like the following:
*
* warning: incompatible integer to pointer conversion passing 'int' to parameter of type 'enum meminfo_item *'
* my_stack = procps_meminfo_select(info, PROCPS_MEMINFO_noop, num);
* ^~~~~~~~~~~~~~~~
*/
if (numitems < 1
|| (void *)items < (void *)(unsigned long)(2 * PROCPS_MEMINFO_logical_end))
return -1;
for (i = 0; i < numitems; i++) {
// a meminfo_item is currently unsigned, but we'll protect our future
if (items[i] < 0)
return -1;
if (items[i] >= PROCPS_MEMINFO_logical_end)
return -1;
}
return 0;
} // end: items_check_failed
static int make_hash_failed (
struct procps_meminfo *info)
{
#define htVAL(f) e.key = STRINGIFY(f) ":"; e.data = &info->hist.new. f; \
if (!hsearch_r(e, ENTER, &ep, &info->hashtab)) return -errno;
#define htXTRA(k,f) e.key = STRINGIFY(k) ":"; e.data = &info->hist.new. f; \
if (!hsearch_r(e, ENTER, &ep, &info->hashtab)) return -errno;
ENTRY e, *ep;
size_t n;
// will also include those 4 derived fields (more is better)
n = sizeof(struct meminfo_data) / sizeof(unsigned long);
// we'll follow the hsearch recommendation of an extra 25%
hcreate_r(n + (n / 4), &info->hashtab);
htVAL(Active)
htXTRA(Active(anon), Active_anon)
htXTRA(Active(file), Active_file)
htVAL(AnonHugePages)
htVAL(AnonPages)
htVAL(Bounce)
htVAL(Buffers)
htVAL(Cached)
htVAL(CmaFree)
htVAL(CmaTotal)
htVAL(CommitLimit)
htVAL(Committed_AS)
htVAL(DirectMap1G)
htVAL(DirectMap2M)
htVAL(DirectMap4k)
htVAL(Dirty)
htVAL(HardwareCorrupted)
htVAL(HighFree)
htVAL(HighTotal)
htVAL(HugePages_Free)
htVAL(HugePages_Rsvd)
htVAL(HugePages_Surp)
htVAL(HugePages_Total)
htVAL(Hugepagesize)
htVAL(Inactive)
htXTRA(Inactive(anon), Inactive_anon)
htXTRA(Inactive(file), Inactive_file)
htVAL(KernelStack)
htVAL(LowFree)
htVAL(LowTotal)
htVAL(Mapped)
htVAL(MemAvailable)
htVAL(MemFree)
htVAL(MemTotal)
htVAL(Mlocked)
htVAL(NFS_Unstable)
htVAL(PageTables)
htVAL(SReclaimable)
htVAL(SUnreclaim)
htVAL(Shmem)
htVAL(Slab)
htVAL(SwapCached)
htVAL(SwapFree)
htVAL(SwapTotal)
htVAL(Unevictable)
htVAL(VmallocChunk)
htVAL(VmallocTotal)
htVAL(VmallocUsed)
htVAL(Writeback)
htVAL(WritebackTmp)
return 0;
#undef htVAL
#undef htXTRA
} // end: make_hash_failed
/*
* read_meminfo_failed():
*
* Read the data out of /proc/meminfo putting the information
* into the supplied info structure
*/
static int read_meminfo_failed (
struct procps_meminfo *info)
{
/* a 'memory history reference' macro for readability,
so we can focus the field names ... */
#define mHr(f) info->hist.new. f
char buf[8192];
char *head, *tail;
int size;
unsigned long *valptr;
signed long mem_used;
if (info == NULL)
return -1;
// remember history from last time around
memcpy(&info->hist.old, &info->hist.new, sizeof(struct meminfo_data));
// clear out the soon to be 'current' values
memset(&info->hist.new, 0, sizeof(struct meminfo_data));
if (-1 == info->meminfo_fd
&& (info->meminfo_fd = open(MEMINFO_FILE, O_RDONLY)) == -1)
return -errno;
if (lseek(info->meminfo_fd, 0L, SEEK_SET) == -1)
return -errno;
for (;;) {
if ((size = read(info->meminfo_fd, buf, sizeof(buf)-1)) < 0) {
if (errno == EINTR || errno == EAGAIN)
continue;
return -errno;
}
break;
}
if (size == 0)
return -1;
buf[size] = '\0';
head = buf;
for (;;) {
static ENTRY e; // just to keep coverity off our backs (e.data)
ENTRY *ep;
tail = strchr(head, ' ');
if (!tail)
break;
*tail = '\0';
valptr = NULL;
e.key = head;
if (hsearch_r(e, FIND, &ep, &info->hashtab))
valptr = ep->data;
head = tail+1;
if (valptr)
*valptr = strtoul(head, &tail, 10);
tail = strchr(head, '\n');
if (!tail)
break;
head = tail + 1;
}
if (0 == mHr(MemAvailable))
mHr(MemAvailable) = mHr(MemFree);
/* if 'available' is greater than 'total' or our calculation of mem_used
overflows, that's symptomatic of running within a lxc container where
such values will be dramatically distorted over those of the host. */
if (mHr(MemAvailable) > mHr(MemTotal))
mHr(MemAvailable) = mHr(MemFree);
mem_used = mHr(MemTotal) - mHr(MemFree) - mHr(Cached) - mHr(Buffers);
if (mem_used < 0)
mem_used = mHr(MemTotal) - mHr(MemFree);
mHr(derived_mem_used) = (unsigned long)mem_used;
if (mHr(HighFree) < mHr(HighTotal))
mHr(derived_mem_hi_used) = mHr(HighTotal) - mHr(HighFree);
mHr(Cached) += mHr(SReclaimable);
if (0 == mHr(LowTotal)) {
mHr(LowTotal) = mHr(MemTotal);
mHr(LowFree) = mHr(MemFree);
}
if (mHr(LowFree) < mHr(LowTotal))
mHr(derived_mem_lo_used) = mHr(LowTotal) - mHr(LowFree);
if (mHr(SwapFree) < mHr(SwapTotal))
mHr(derived_swap_used) = mHr(SwapTotal) - mHr(SwapFree);
// let's not distort the deltas the first time thru ...
if (!info->meminfo_was_read)
memcpy(&info->hist.old, &info->hist.new, sizeof(struct meminfo_data));
info->meminfo_was_read = 1;
return 0;
#undef mHr
} // end: read_meminfo_failed
/*
* stacks_alloc():
*
* Allocate and initialize one or more stacks each of which is anchored in an
* associated meminfo_stack structure.
*
* All such stacks will have their result structures properly primed with
* 'items', while the result itself will be zeroed.
*
* Returns a stacks_extent struct anchoring the 'heads' of each new stack.
*/
static struct stacks_extent *stacks_alloc (
struct procps_meminfo *info,
int maxstacks)
{
struct stacks_extent *p_blob;
struct meminfo_stack **p_vect;
struct meminfo_stack *p_head;
size_t vect_size, head_size, list_size, blob_size;
void *v_head, *v_list;
int i;
if (info == NULL || info->items == NULL)
return NULL;
if (maxstacks < 1)
return NULL;
vect_size = sizeof(void *) * maxstacks; // size of the addr vectors |
vect_size += sizeof(void *); // plus NULL addr delimiter |
head_size = sizeof(struct meminfo_stack); // size of that head struct |
list_size = sizeof(struct meminfo_result)*info->numitems; // any single results stack |
blob_size = sizeof(struct stacks_extent); // the extent anchor itself |
blob_size += vect_size; // plus room for addr vects |
blob_size += head_size * maxstacks; // plus room for head thing |
blob_size += list_size * maxstacks; // plus room for our stacks |
/* note: all of our memory is allocated in a single blob, facilitating a later free(). |
as a minimum, it is important that the result structures themselves always be |
contiguous for every stack since they are accessed through relative position. | */
if (NULL == (p_blob = calloc(1, blob_size)))
return NULL;
p_blob->next = info->extents; // push this extent onto... |
info->extents = p_blob; // ...some existing extents |
p_vect = (void *)p_blob + sizeof(struct stacks_extent); // prime our vector pointer |
p_blob->stacks = p_vect; // set actual vectors start |
v_head = (void *)p_vect + vect_size; // prime head pointer start |
v_list = v_head + (head_size * maxstacks); // prime our stacks pointer |
for (i = 0; i < maxstacks; i++) {
p_head = (struct meminfo_stack *)v_head;
p_head->head = itemize_stack((struct meminfo_result *)v_list, info->numitems, info->items);
p_blob->stacks[i] = p_head;
v_list += list_size;
v_head += head_size;
}
p_blob->ext_numstacks = maxstacks;
return p_blob;
} // end: stacks_alloc
// ___ Public Functions |||||||||||||||||||||||||||||||||||||||||||||||||||||||
// --- standard required functions --------------------------------------------
/*
* procps_meminfo_new:
*
* Create a new container to hold the stat information
*
* The initial refcount is 1, and needs to be decremented
* to release the resources of the structure.
*
* Returns: a pointer to a new meminfo struct
*/
PROCPS_EXPORT int procps_meminfo_new (
struct procps_meminfo **info)
{
struct procps_meminfo *p;
int rc;
if (info == NULL || *info != NULL)
return -EINVAL;
if (!(p = calloc(1, sizeof(struct procps_meminfo))))
return -ENOMEM;
p->refcount = 1;
p->meminfo_fd = -1;
if ((rc = make_hash_failed(p))) {
free(p);
return rc;
}
*info = p;
return 0;
} // end: procps_meminfo_new
PROCPS_EXPORT int procps_meminfo_ref (
struct procps_meminfo *info)
{
if (info == NULL)
return -EINVAL;
info->refcount++;
return info->refcount;
} // end: procps_meminfo_ref
PROCPS_EXPORT int procps_meminfo_unref (
struct procps_meminfo **info)
{
if (info == NULL || *info == NULL)
return -EINVAL;
(*info)->refcount--;
if ((*info)->refcount == 0) {
if ((*info)->extents)
extents_free_all((*info));
if ((*info)->items)
free((*info)->items);
hdestroy_r(&(*info)->hashtab);
free(*info);
*info = NULL;
return 0;
}
return (*info)->refcount;
} // end: procps_meminfo_unref
// --- variable interface functions -------------------------------------------
PROCPS_EXPORT struct meminfo_result *procps_meminfo_get (
struct procps_meminfo *info,
enum meminfo_item item)
{
static time_t sav_secs;
time_t cur_secs;
if (info == NULL)
return NULL;
if (item < 0 || item >= PROCPS_MEMINFO_logical_end)
return NULL;
/* we will NOT read the meminfo file with every call - rather, we'll offer
a granularity of 1 second between reads ... */
cur_secs = time(NULL);
if (1 <= cur_secs - sav_secs) {
if (read_meminfo_failed(info))
return NULL;
sav_secs = cur_secs;
}
info->get_this.item = item;
// with 'get', we must NOT honor the usual 'noop' guarantee
// if (item > PROCPS_MEMINFO_noop)
info->get_this.result.ul_int = 0;
Item_table[item].setsfunc(&info->get_this, &info->hist);
return &info->get_this;
} // end: procps_meminfo_get
/* procps_meminfo_select():
*
* Harvest all the requested MEM and/or SWAP information then return
* it in a results stack.
*
* Returns: pointer to a meminfo_stack struct on success, NULL on error.
*/
PROCPS_EXPORT struct meminfo_stack *procps_meminfo_select (
struct procps_meminfo *info,
enum meminfo_item *items,
int numitems)
{
if (info == NULL || items == NULL)
return NULL;
if (items_check_failed(numitems, items))
return NULL;
/* is this the first time or have things changed since we were last called?
if so, gotta' redo all of our stacks stuff ... */
if (info->numitems != numitems + 1
|| memcmp(info->items, items, sizeof(enum meminfo_item) * numitems)) {
// allow for our PROCPS_MEMINFO_logical_end
if (!(info->items = realloc(info->items, sizeof(enum meminfo_item) * (numitems + 1))))
return NULL;
memcpy(info->items, items, sizeof(enum meminfo_item) * numitems);
info->items[numitems] = PROCPS_MEMINFO_logical_end;
info->numitems = numitems + 1;
if (info->extents)
extents_free_all(info);
}
if (!info->extents
&& !(stacks_alloc(info, 1)))
return NULL;
if (info->dirty_stacks)
cleanup_stacks_all(info);
if (read_meminfo_failed(info))
return NULL;
assign_results(info->extents->stacks[0], &info->hist);
info->dirty_stacks = 1;
return info->extents->stacks[0];
} // end: procps_meminfo_select
Reference in New Issue View Git Blame Copy Permalink